mirror of https://gitee.com/openkylin/linux.git
12553 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Michal Hocko
|
15c30bc090 |
mm, memory_hotplug: make has_unmovable_pages more robust
Oscar has reported:
: Due to an unfortunate setting with movablecore, memblocks containing bootmem
: memory (pages marked by get_page_bootmem()) ended up marked in zone_movable.
: So while trying to remove that memory, the system failed in do_migrate_range
: and __offline_pages never returned.
:
: This can be reproduced by running
: qemu-system-x86_64 -m 6G,slots=8,maxmem=8G -numa node,mem=4096M -numa node,mem=2048M
: and movablecore=4G kernel command line
:
: linux kernel: BIOS-provided physical RAM map:
: linux kernel: BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
: linux kernel: BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
: linux kernel: BIOS-e820: [mem 0x0000000000100000-0x00000000bffdffff] usable
: linux kernel: BIOS-e820: [mem 0x00000000bffe0000-0x00000000bfffffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
: linux kernel: BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
: linux kernel: BIOS-e820: [mem 0x0000000100000000-0x00000001bfffffff] usable
: linux kernel: NX (Execute Disable) protection: active
: linux kernel: SMBIOS 2.8 present.
: linux kernel: DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org
: linux kernel: Hypervisor detected: KVM
: linux kernel: e820: update [mem 0x00000000-0x00000fff] usable ==> reserved
: linux kernel: e820: remove [mem 0x000a0000-0x000fffff] usable
: linux kernel: last_pfn = 0x1c0000 max_arch_pfn = 0x400000000
:
: linux kernel: SRAT: PXM 0 -> APIC 0x00 -> Node 0
: linux kernel: SRAT: PXM 1 -> APIC 0x01 -> Node 1
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00000000-0x0009ffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x00100000-0xbfffffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0x13fffffff]
: linux kernel: ACPI: SRAT: Node 1 PXM 1 [mem 0x140000000-0x1bfffffff]
: linux kernel: ACPI: SRAT: Node 0 PXM 0 [mem 0x1c0000000-0x43fffffff] hotplug
: linux kernel: NUMA: Node 0 [mem 0x00000000-0x0009ffff] + [mem 0x00100000-0xbfffffff] -> [mem 0x0
: linux kernel: NUMA: Node 0 [mem 0x00000000-0xbfffffff] + [mem 0x100000000-0x13fffffff] -> [mem 0
: linux kernel: NODE_DATA(0) allocated [mem 0x13ffd6000-0x13fffffff]
: linux kernel: NODE_DATA(1) allocated [mem 0x1bffd3000-0x1bfffcfff]
:
: zoneinfo shows that the zone movable is placed into both numa nodes:
: Node 0, zone Movable
: pages free 160140
: min 1823
: low 2278
: high 2733
: spanned 262144
: present 262144
: managed 245670
: Node 1, zone Movable
: pages free 448427
: min 3827
: low 4783
: high 5739
: spanned 524288
: present 524288
: managed 515766
Note how only Node 0 has a hutplugable memory region which would rule it
out from the early memblock allocations (most likely memmap). Node1
will surely contain memmaps on the same node and those would prevent
offlining to succeed. So this is arguably a configuration issue.
Although one could argue that we should be more clever and rule early
allocations from the zone movable. This would be correct but probably
not worth the effort considering what a hack movablecore is.
Anyway, We could do better for those cases though. We rely on
start_isolate_page_range resp. has_unmovable_pages to do their job.
The first one isolates the whole range to be offlined so that we do not
allocate from it anymore and the later makes sure we are not stumbling
over non-migrateable pages.
has_unmovable_pages is overly optimistic, however. It doesn't check all
the pages if we are withing zone_movable because we rely that those
pages will be always migrateable. As it turns out we are still not
perfect there. While bootmem pages in zonemovable sound like a clear
bug which should be fixed let's remove the optimization for now and warn
if we encounter unmovable pages in zone_movable in the meantime. That
should help for now at least.
Btw. this wasn't a real problem until commit
|
|
|
Andrey Ryabinin
|
0f901dcbc3 |
mm/kasan: don't vfree() nonexistent vm_area
KASAN uses different routines to map shadow for hot added memory and
memory obtained in boot process. Attempt to offline memory onlined by
normal boot process leads to this:
Trying to vfree() nonexistent vm area (000000005d3b34b9)
WARNING: CPU: 2 PID: 13215 at mm/vmalloc.c:1525 __vunmap+0x147/0x190
Call Trace:
kasan_mem_notifier+0xad/0xb9
notifier_call_chain+0x166/0x260
__blocking_notifier_call_chain+0xdb/0x140
__offline_pages+0x96a/0xb10
memory_subsys_offline+0x76/0xc0
device_offline+0xb8/0x120
store_mem_state+0xfa/0x120
kernfs_fop_write+0x1d5/0x320
__vfs_write+0xd4/0x530
vfs_write+0x105/0x340
SyS_write+0xb0/0x140
Obviously we can't call vfree() to free memory that wasn't allocated via
vmalloc(). Use find_vm_area() to see if we can call vfree().
Unfortunately it's a bit tricky to properly unmap and free shadow
allocated during boot, so we'll have to keep it. If memory will come
online again that shadow will be reused.
Matthew asked: how can you call vfree() on something that isn't a
vmalloc address?
vfree() is able to free any address returned by
__vmalloc_node_range(). And __vmalloc_node_range() gives you any
address you ask. It doesn't have to be an address in [VMALLOC_START,
VMALLOC_END] range.
That's also how the module_alloc()/module_memfree() works on
architectures that have designated area for modules.
[aryabinin@virtuozzo.com: improve comments]
Link: http://lkml.kernel.org/r/dabee6ab-3a7a-51cd-3b86-5468718e0390@virtuozzo.com
[akpm@linux-foundation.org: fix typos, reflow comment]
Link: http://lkml.kernel.org/r/20180201163349.8700-1-aryabinin@virtuozzo.com
Fixes:
|
|
|
Omar Sandoval
|
7cbf319234 |
mm: fix nr_rotate_swap leak in swapon() error case
If swapon() fails after incrementing nr_rotate_swap, we don't decrement
it and thus effectively leak it. Make sure we decrement it if we
incremented it.
Link: http://lkml.kernel.org/r/b6fe6b879f17fa68eee6cbd876f459f6e5e33495.1526491581.git.osandov@fb.com
Fixes:
|
|
|
Joonsoo Kim
|
d883c6cf3b |
Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE"
This reverts the following commits that change CMA design in MM. |
|
|
Tejun Heo
|
f183464684 |
bdi: Move cgroup bdi_writeback to a dedicated low concurrency workqueue
From 0aa2e9b921d6db71150633ff290199554f0842a8 Mon Sep 17 00:00:00 2001 From: Tejun Heo <tj@kernel.org> Date: Wed, 23 May 2018 10:29:00 -0700 cgwb_release() punts the actual release to cgwb_release_workfn() on system_wq. Depending on the number of cgroups or block devices, there can be a lot of cgwb_release_workfn() in flight at the same time. We're periodically seeing close to 256 kworkers getting stuck with the following stack trace and overtime the entire system gets stuck. [<ffffffff810ee40c>] _synchronize_rcu_expedited.constprop.72+0x2fc/0x330 [<ffffffff810ee634>] synchronize_rcu_expedited+0x24/0x30 [<ffffffff811ccf23>] bdi_unregister+0x53/0x290 [<ffffffff811cd1e9>] release_bdi+0x89/0xc0 [<ffffffff811cd645>] wb_exit+0x85/0xa0 [<ffffffff811cdc84>] cgwb_release_workfn+0x54/0xb0 [<ffffffff810a68d0>] process_one_work+0x150/0x410 [<ffffffff810a71fd>] worker_thread+0x6d/0x520 [<ffffffff810ad3dc>] kthread+0x12c/0x160 [<ffffffff81969019>] ret_from_fork+0x29/0x40 [<ffffffffffffffff>] 0xffffffffffffffff The events leading to the lockup are... 1. A lot of cgwb_release_workfn() is queued at the same time and all system_wq kworkers are assigned to execute them. 2. They all end up calling synchronize_rcu_expedited(). One of them wins and tries to perform the expedited synchronization. 3. However, that invovles queueing rcu_exp_work to system_wq and waiting for it. Because #1 is holding all available kworkers on system_wq, rcu_exp_work can't be executed. cgwb_release_workfn() is waiting for synchronize_rcu_expedited() which in turn is waiting for cgwb_release_workfn() to free up some of the kworkers. We shouldn't be scheduling hundreds of cgwb_release_workfn() at the same time. There's nothing to be gained from that. This patch updates cgwb release path to use a dedicated percpu workqueue with @max_active of 1. While this resolves the problem at hand, it might be a good idea to isolate rcu_exp_work to its own workqueue too as it can be used from various paths and is prone to this sort of indirect A-A deadlocks. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk> |
|
|
Dan Williams
|
a9b6de77b1 |
mm: fix __gup_device_huge vs unmap
get_user_pages_fast() for device pages is missing the typical validation
that all page references have been taken while the mapping was valid.
Without this validation truncate operations can not reliably coordinate
against new page reference events like O_DIRECT.
Cc: <stable@vger.kernel.org>
Fixes:
|
|
|
Dan Williams
|
e763848843 |
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
In preparation for fixing dax-dma-vs-unmap issues, filesystems need to be able to rely on the fact that they will get wakeups on dev_pagemap page-idle events. Introduce MEMORY_DEVICE_FS_DAX and generic_dax_page_free() as common indicator / infrastructure for dax filesytems to require. With this change there are no users of the MEMORY_DEVICE_HOST designation, so remove it. The HMM sub-system extended dev_pagemap to arrange a callback when a dev_pagemap managed page is freed. Since a dev_pagemap page is free / idle when its reference count is 1 it requires an additional branch to check the page-type at put_page() time. Given put_page() is a hot-path we do not want to incur that check if HMM is not in use, so a static branch is used to avoid that overhead when not necessary. Now, the FS_DAX implementation wants to reuse this mechanism for receiving dev_pagemap ->page_free() callbacks. Rework the HMM-specific static-key into a generic mechanism that either HMM or FS_DAX code paths can enable. For ARCH=um builds, and any other arch that lacks ZONE_DEVICE support, care must be taken to compile out the DEV_PAGEMAP_OPS infrastructure. However, we still need to support FS_DAX in the FS_DAX_LIMITED case implemented by the s390/dcssblk driver. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Thomas Meyer <thomas@m3y3r.de> Reported-by: Dave Jiang <dave.jiang@intel.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
|
|
Linus Torvalds
|
423913ad4a |
mmap: relax file size limit for regular files
Commit |
|
|
Pavel Tatashin
|
ab1e8d8960 |
mm: don't allow deferred pages with NEED_PER_CPU_KM
It is unsafe to do virtual to physical translations before mm_init() is called if struct page is needed in order to determine the memory section number (see SECTION_IN_PAGE_FLAGS). This is because only in mm_init() we initialize struct pages for all the allocated memory when deferred struct pages are used. My recent fix in commit |
|
|
Willy Tarreau
|
7f7ccc2ccc |
proc: do not access cmdline nor environ from file-backed areas
proc_pid_cmdline_read() and environ_read() directly access the target process' VM to retrieve the command line and environment. If this process remaps these areas onto a file via mmap(), the requesting process may experience various issues such as extra delays if the underlying device is slow to respond. Let's simply refuse to access file-backed areas in these functions. For this we add a new FOLL_ANON gup flag that is passed to all calls to access_remote_vm(). The code already takes care of such failures (including unmapped areas). Accesses via /proc/pid/mem were not changed though. This was assigned CVE-2018-1120. Note for stable backports: the patch may apply to kernels prior to 4.11 but silently miss one location; it must be checked that no call to access_remote_vm() keeps zero as the last argument. Reported-by: Qualys Security Advisory <qsa@qualys.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Christoph Hellwig
|
44414d82cf |
proc: introduce proc_create_seq_private
Variant of proc_create_data that directly take a struct seq_operations argument + a private state size and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de> |
|
|
Christoph Hellwig
|
fddda2b7b5 |
proc: introduce proc_create_seq{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations
argument and drastically reduces the boilerplate code in the callers.
All trivial callers converted over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
|
|
|
Kent Overstreet
|
c1a67fefd0 |
mempool: Add mempool_init()/mempool_exit()
Allows mempools to be embedded in other structs, getting rid of a pointer indirection from allocation fastpaths. mempool_exit() is safe to call on an uninitialized but zeroed mempool. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
|
|
Linus Torvalds
|
f0ab773f5c |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton: "13 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: rbtree: include rcu.h scripts/faddr2line: fix error when addr2line output contains discriminator ocfs2: take inode cluster lock before moving reflinked inode from orphan dir mm, oom: fix concurrent munlock and oom reaper unmap, v3 mm: migrate: fix double call of radix_tree_replace_slot() proc/kcore: don't bounds check against address 0 mm: don't show nr_indirectly_reclaimable in /proc/vmstat mm: sections are not offlined during memory hotremove z3fold: fix reclaim lock-ups init: fix false positives in W+X checking lib/find_bit_benchmark.c: avoid soft lockup in test_find_first_bit() KASAN: prohibit KASAN+STRUCTLEAK combination MAINTAINERS: update Shuah's email address |
|
|
David Rientjes
|
27ae357fa8 |
mm, oom: fix concurrent munlock and oom reaper unmap, v3
Since exit_mmap() is done without the protection of mm->mmap_sem, it is
possible for the oom reaper to concurrently operate on an mm until
MMF_OOM_SKIP is set.
This allows munlock_vma_pages_all() to concurrently run while the oom
reaper is operating on a vma. Since munlock_vma_pages_range() depends
on clearing VM_LOCKED from vm_flags before actually doing the munlock to
determine if any other vmas are locking the same memory, the check for
VM_LOCKED in the oom reaper is racy.
This is especially noticeable on architectures such as powerpc where
clearing a huge pmd requires serialize_against_pte_lookup(). If the pmd
is zapped by the oom reaper during follow_page_mask() after the check
for pmd_none() is bypassed, this ends up deferencing a NULL ptl or a
kernel oops.
Fix this by manually freeing all possible memory from the mm before
doing the munlock and then setting MMF_OOM_SKIP. The oom reaper can not
run on the mm anymore so the munlock is safe to do in exit_mmap(). It
also matches the logic that the oom reaper currently uses for
determining when to set MMF_OOM_SKIP itself, so there's no new risk of
excessive oom killing.
This issue fixes CVE-2018-1000200.
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1804241526320.238665@chino.kir.corp.google.com
Fixes:
|
|
|
Naoya Horiguchi
|
013567be19 |
mm: migrate: fix double call of radix_tree_replace_slot()
radix_tree_replace_slot() is called twice for head page, it's obviously
a bug. Let's fix it.
Link: http://lkml.kernel.org/r/20180423072101.GA12157@hori1.linux.bs1.fc.nec.co.jp
Fixes:
|
|
|
Roman Gushchin
|
7aaf772723 |
mm: don't show nr_indirectly_reclaimable in /proc/vmstat
Don't show nr_indirectly_reclaimable in /proc/vmstat, because there is no need to export this vm counter to userspace, and some changes are expected in reclaimable object accounting, which can alter this counter. Link: http://lkml.kernel.org/r/20180425191422.9159-1-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
27227c7338 |
mm: sections are not offlined during memory hotremove
Memory hotplug and hotremove operate with per-block granularity. If the
machine has a large amount of memory (more than 64G), the size of a
memory block can span multiple sections. By mistake, during hotremove
we set only the first section to offline state.
The bug was discovered because kernel selftest started to fail:
https://lkml.kernel.org/r/20180423011247.GK5563@yexl-desktop
After commit, "mm/memory_hotplug: optimize probe routine". But, the bug
is older than this commit. In this optimization we also added a check
for sections to be in a proper state during hotplug operation.
Link: http://lkml.kernel.org/r/20180427145257.15222-1-pasha.tatashin@oracle.com
Fixes:
|
|
|
Vitaly Wool
|
6098d7e136 |
z3fold: fix reclaim lock-ups
Do not try to optimize in-page object layout while the page is under reclaim. This fixes lock-ups on reclaim and improves reclaim performance at the same time. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20180430125800.444cae9706489f412ad12621@gmail.com Signed-off-by: Vitaly Wool <vitaly.vul@sony.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: <Oleksiy.Avramchenko@sony.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Linus Torvalds
|
be83bbf806 |
mmap: introduce sane default mmap limits
The internal VM "mmap()" interfaces are based on the mmap target doing everything using page indexes rather than byte offsets, because traditionally (ie 32-bit) we had the situation that the byte offset didn't fit in a register. So while the mmap virtual address was limited by the word size of the architecture, the backing store was not. So we're basically passing "pgoff" around as a page index, in order to be able to describe backing store locations that are much bigger than the word size (think files larger than 4GB etc). But while this all makes a ton of sense conceptually, we've been dogged by various drivers that don't really understand this, and internally work with byte offsets, and then try to work with the page index by turning it into a byte offset with "pgoff << PAGE_SHIFT". Which obviously can overflow. Adding the size of the mapping to it to get the byte offset of the end of the backing store just exacerbates the problem, and if you then use this overflow-prone value to check various limits of your device driver mmap capability, you're just setting yourself up for problems. The correct thing for drivers to do is to do their limit math in page indices, the way the interface is designed. Because the generic mmap code _does_ test that the index doesn't overflow, since that's what the mmap code really cares about. HOWEVER. Finding and fixing various random drivers is a sisyphean task, so let's just see if we can just make the core mmap() code do the limiting for us. Realistically, the only "big" backing stores we need to care about are regular files and block devices, both of which are known to do this properly, and which have nice well-defined limits for how much data they can access. So let's special-case just those two known cases, and then limit other random mmap users to a backing store that still fits in "unsigned long". Realistically, that's not much of a limit at all on 64-bit, and on 32-bit architectures the only worry might be the GPU drivers, which can have big physical address spaces. To make it possible for drivers like that to say that they are 64-bit clean, this patch does repurpose the "FMODE_UNSIGNED_OFFSET" bit in the file flags to allow drivers to mark their file descriptors as safe in the full 64-bit mmap address space. [ The timing for doing this is less than optimal, and this should really go in a merge window. But realistically, this needs wide testing more than it needs anything else, and being main-line is the only way to do that. So the earlier the better, even if it's outside the proper development cycle - Linus ] Cc: Kees Cook <keescook@chromium.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Willy Tarreau <w@1wt.eu> Cc: Dave Airlie <airlied@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Christoph Hellwig
|
d4a451d5fc |
arch: remove the ARCH_PHYS_ADDR_T_64BIT config symbol
Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a 64-bit phys_addr_t type directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: James Hogan <jhogan@kernel.org> |
|
|
Linus Torvalds
|
2f50037a1c |
for-linus-20180504
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=P6V8
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20180504' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A collection of fixes that should to into this release. This contains:
- Set of bcache fixes from Coly, fixing regression in patches that
went into this series.
- Set of NVMe fixes by way of Keith.
- Set of bdi related fixes, one from Jan and two from Tetsuo Handa,
fixing various issues around device addition/removal.
- Two block inflight fixes from Omar, fixing issues around the
transition to using tags for blk-mq inflight accounting that we
did a few releases ago"
* tag 'for-linus-20180504' of git://git.kernel.dk/linux-block:
bdi: Fix oops in wb_workfn()
nvmet: switch loopback target state to connecting when resetting
nvme/multipath: Fix multipath disabled naming collisions
nvme/multipath: Disable runtime writable enabling parameter
nvme: Set integrity flag for user passthrough commands
nvme: fix potential memory leak in option parsing
bdi: Fix use after free bug in debugfs_remove()
bdi: wake up concurrent wb_shutdown() callers.
bcache: use pr_info() to inform duplicated CACHE_SET_IO_DISABLE set
bcache: set dc->io_disable to true in conditional_stop_bcache_device()
bcache: add wait_for_kthread_stop() in bch_allocator_thread()
bcache: count backing device I/O error for writeback I/O
bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()
bcache: store disk name in struct cache and struct cached_dev
blk-mq: fix sysfs inflight counter
blk-mq: count allocated but not started requests in iostats inflight
|
|
|
Tetsuo Handa
|
f53823c181 |
bdi: Fix use after free bug in debugfs_remove()
syzbot is reporting use after free bug in debugfs_remove() [1].
This is because fault injection made memory allocation for
debugfs_create_file() from bdi_debug_register() from bdi_register_va()
fail and continued with setting WB_registered. But when debugfs_remove()
is called from debugfs_remove(bdi->debug_dir) from bdi_debug_unregister()
from bdi_unregister() from release_bdi() because WB_registered was set
by bdi_register_va(), IS_ERR_OR_NULL(bdi->debug_dir) == false despite
debugfs_remove(bdi->debug_dir) was already called from bdi_register_va().
Fix this by making IS_ERR_OR_NULL(bdi->debug_dir) == true.
[1] https://syzkaller.appspot.com/bug?id=5ab4efd91a96dcea9b68104f159adf4af2a6dfc1
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+049cb4ae097049dac137@syzkaller.appspotmail.com>
Fixes:
|
|
|
Tetsuo Handa
|
8236b0ae31 |
bdi: wake up concurrent wb_shutdown() callers.
syzbot is reporting hung tasks at wait_on_bit(WB_shutting_down) in wb_shutdown() [1]. This seems to be because commit |
|
|
Mike Rapoport
|
5a2ca3efe6 |
mm/ksm: docs: extend overview comment and make it "DOC:"
The existing comment provides a good overview of KSM implementation. Let's update it to reflect recent additions of "chain" and "dup" variants of the stable tree nodes and mark it as "DOC:" for inclusion into the KSM documentation. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
|
|
Jonathan Corbet
|
ccf2b06794 |
Linux 4.17-rc2
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlrdQu4eHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGVjEIAJqS+sFJCAL8rNAv tiVJHuAjogVdZGJJFBUWyb4yNZw7nRSKfitaSe875WdF55IGEhnMDbAGe7IMEb5j 1F8Ml2bzJzMWxfBWAzeU+wj6FaQksbIsI1gVM8tqk/Wtu121pB32VW8R82oHg+Hr sjsFTKFicNsqih+7QTVujaRjSmabKf0/JdyYM6p1cqWrxZQ0pmFaGDu0rwet9PFx lJsewOmnoZ0GV/Qzn40E304Xf+Vv2gVDVbC5wY86ejNigFt+5qN+gtDqDu7UkftR ZfD4vJuiKCigNfUrpbJWfpbegBiQc0JMvjLWWhgo/AYdGhNGMlwjQanh2oZcXlrw VmrNduo= =/j3z -----END PGP SIGNATURE----- Merge tag 'v4.17-rc2' into docs-next Merge -rc2 to pick up the changes to Documentation/core-api/kernel-api.rst that hit mainline via the networking tree. In their absence, subsequent patches cannot be applied. |
|
|
Mike Rapoport
|
1ad1335dc5 |
docs/admin-guide/mm: start moving here files from Documentation/vm
Several documents in Documentation/vm fit quite well into the "admin/user guide" category. The documents that don't overload the reader with lots of implementation details and provide coherent description of certain feature can be moved to Documentation/admin-guide/mm. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
|
|
Dave Hansen
|
316d097c4c |
x86/pti: Filter at vma->vm_page_prot population
commit ce9962bf7e22bb3891655c349faff618922d4a73
0day reported warnings at boot on 32-bit systems without NX support:
attempted to set unsupported pgprot: 8000000000000025 bits: 8000000000000000 supported: 7fffffffffffffff
WARNING: CPU: 0 PID: 1 at
arch/x86/include/asm/pgtable.h:540 handle_mm_fault+0xfc1/0xfe0:
check_pgprot at arch/x86/include/asm/pgtable.h:535
(inlined by) pfn_pte at arch/x86/include/asm/pgtable.h:549
(inlined by) do_anonymous_page at mm/memory.c:3169
(inlined by) handle_pte_fault at mm/memory.c:3961
(inlined by) __handle_mm_fault at mm/memory.c:4087
(inlined by) handle_mm_fault at mm/memory.c:4124
The problem is that due to the recent commit which removed auto-massaging
of page protections, filtering page permissions at PTE creation time is not
longer done, so vma->vm_page_prot is passed unfiltered to PTE creation.
Filter the page protections before they are installed in vma->vm_page_prot.
Fixes:
|
|
|
Matthew Wilcox
|
abc1be13fd |
mm/filemap.c: fix NULL pointer in page_cache_tree_insert()
f2fs specifies the __GFP_ZERO flag for allocating some of its pages.
Unfortunately, the page cache also uses the mapping's GFP flags for
allocating radix tree nodes. It always masked off the __GFP_HIGHMEM
flag, and masks off __GFP_ZERO in some paths, but not all. That causes
radix tree nodes to be allocated with a NULL list_head, which causes
backtraces like:
__list_del_entry+0x30/0xd0
list_lru_del+0xac/0x1ac
page_cache_tree_insert+0xd8/0x110
The __GFP_DMA and __GFP_DMA32 flags would also be able to sneak through
if they are ever used. Fix them all by using GFP_RECLAIM_MASK at the
innermost location, and remove it from earlier in the callchain.
Link: http://lkml.kernel.org/r/20180411060320.14458-2-willy@infradead.org
Fixes:
|
|
|
Minchan Kim
|
c892fd82cc |
mm: memcg: add __GFP_NOWARN in __memcg_schedule_kmem_cache_create()
If there is heavy memory pressure, page allocation with __GFP_NOWAIT
fails easily although it's order-0 request. I got below warning 9 times
for normal boot.
<snip >: page allocation failure: order:0, mode:0x2200000(GFP_NOWAIT|__GFP_NOTRACK)
.. snip ..
Call trace:
dump_backtrace+0x0/0x4
dump_stack+0xa4/0xc0
warn_alloc+0xd4/0x15c
__alloc_pages_nodemask+0xf88/0x10fc
alloc_slab_page+0x40/0x18c
new_slab+0x2b8/0x2e0
___slab_alloc+0x25c/0x464
__kmalloc+0x394/0x498
memcg_kmem_get_cache+0x114/0x2b8
kmem_cache_alloc+0x98/0x3e8
mmap_region+0x3bc/0x8c0
do_mmap+0x40c/0x43c
vm_mmap_pgoff+0x15c/0x1e4
sys_mmap+0xb0/0xc8
el0_svc_naked+0x24/0x28
Mem-Info:
active_anon:17124 inactive_anon:193 isolated_anon:0
active_file:7898 inactive_file:712955 isolated_file:55
unevictable:0 dirty:27 writeback:18 unstable:0
slab_reclaimable:12250 slab_unreclaimable:23334
mapped:19310 shmem:212 pagetables:816 bounce:0
free:36561 free_pcp:1205 free_cma:35615
Node 0 active_anon:68496kB inactive_anon:772kB active_file:31592kB inactive_file:2851820kB unevictable:0kB isolated(anon):0kB isolated(file):220kB mapped:77240kB dirty:108kB writeback:72kB shmem:848kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no
DMA free:142188kB min:3056kB low:3820kB high:4584kB active_anon:10052kB inactive_anon:12kB active_file:312kB inactive_file:1412620kB unevictable:0kB writepending:0kB present:1781412kB managed:1604728kB mlocked:0kB slab_reclaimable:3592kB slab_unreclaimable:876kB kernel_stack:400kB pagetables:52kB bounce:0kB free_pcp:1436kB local_pcp:124kB free_cma:142492kB
lowmem_reserve[]: 0 1842 1842
Normal free:4056kB min:4172kB low:5212kB high:6252kB active_anon:58376kB inactive_anon:760kB active_file:31348kB inactive_file:1439040kB unevictable:0kB writepending:180kB present:2000636kB managed:1923688kB mlocked:0kB slab_reclaimable:45408kB slab_unreclaimable:92460kB kernel_stack:9680kB pagetables:3212kB bounce:0kB free_pcp:3392kB local_pcp:688kB free_cma:0kB
lowmem_reserve[]: 0 0 0
DMA: 0*4kB 0*8kB 1*16kB (C) 0*32kB 0*64kB 0*128kB 1*256kB (C) 1*512kB (C) 0*1024kB 1*2048kB (C) 34*4096kB (C) = 142096kB
Normal: 228*4kB (UMEH) 172*8kB (UMH) 23*16kB (UH) 24*32kB (H) 5*64kB (H) 1*128kB (H) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3872kB
721350 total pagecache pages
0 pages in swap cache
Swap cache stats: add 0, delete 0, find 0/0
Free swap = 0kB
Total swap = 0kB
945512 pages RAM
0 pages HighMem/MovableOnly
63408 pages reserved
51200 pages cma reserved
__memcg_schedule_kmem_cache_create() tries to create a shadow slab cache
and the worker allocation failure is not really critical because we will
retry on the next kmem charge. We might miss some charges but that
shouldn't be critical. The excessive allocation failure report is not
very helpful.
[mhocko@kernel.org: changelog update]
Link: http://lkml.kernel.org/r/20180418022912.248417-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Naoya Horiguchi
|
e71769ae52 |
mm: enable thp migration for shmem thp
My testing for the latest kernel supporting thp migration showed an
infinite loop in offlining the memory block that is filled with shmem
thps. We can get out of the loop with a signal, but kernel should return
with failure in this case.
What happens in the loop is that scan_movable_pages() repeats returning
the same pfn without any progress. That's because page migration always
fails for shmem thps.
In memory offline code, memory blocks containing unmovable pages should be
prevented from being offline targets by has_unmovable_pages() inside
start_isolate_page_range(). So it's possible to change migratability for
non-anonymous thps to avoid the issue, but it introduces more complex and
thp-specific handling in migration code, so it might not good.
So this patch is suggesting to fix the issue by enabling thp migration for
shmem thp. Both of anon/shmem thp are migratable so we don't need
precheck about the type of thps.
Link: http://lkml.kernel.org/r/20180406030706.GA2434@hori1.linux.bs1.fc.nec.co.jp
Fixes: commit
|
|
|
Greg Thelen
|
2e898e4c0a |
writeback: safer lock nesting
lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if
the page's memcg is undergoing move accounting, which occurs when a
process leaves its memcg for a new one that has
memory.move_charge_at_immigrate set.
unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if
the given inode is switching writeback domains. Switches occur when
enough writes are issued from a new domain.
This existing pattern is thus suspicious:
lock_page_memcg(page);
unlocked_inode_to_wb_begin(inode, &locked);
...
unlocked_inode_to_wb_end(inode, locked);
unlock_page_memcg(page);
If both inode switch and process memcg migration are both in-flight then
unlocked_inode_to_wb_end() will unconditionally enable interrupts while
still holding the lock_page_memcg() irq spinlock. This suggests the
possibility of deadlock if an interrupt occurs before unlock_page_memcg().
truncate
__cancel_dirty_page
lock_page_memcg
unlocked_inode_to_wb_begin
unlocked_inode_to_wb_end
<interrupts mistakenly enabled>
<interrupt>
end_page_writeback
test_clear_page_writeback
lock_page_memcg
<deadlock>
unlock_page_memcg
Due to configuration limitations this deadlock is not currently possible
because we don't mix cgroup writeback (a cgroupv2 feature) and
memory.move_charge_at_immigrate (a cgroupv1 feature).
If the kernel is hacked to always claim inode switching and memcg
moving_account, then this script triggers lockup in less than a minute:
cd /mnt/cgroup/memory
mkdir a b
echo 1 > a/memory.move_charge_at_immigrate
echo 1 > b/memory.move_charge_at_immigrate
(
echo $BASHPID > a/cgroup.procs
while true; do
dd if=/dev/zero of=/mnt/big bs=1M count=256
done
) &
while true; do
sync
done &
sleep 1h &
SLEEP=$!
while true; do
echo $SLEEP > a/cgroup.procs
echo $SLEEP > b/cgroup.procs
done
The deadlock does not seem possible, so it's debatable if there's any
reason to modify the kernel. I suggest we should to prevent future
surprises. And Wang Long said "this deadlock occurs three times in our
environment", so there's more reason to apply this, even to stable.
Stable 4.4 has minor conflicts applying this patch. For a clean 4.4 patch
see "[PATCH for-4.4] writeback: safer lock nesting"
https://lkml.org/lkml/2018/4/11/146
Wang Long said "this deadlock occurs three times in our environment"
[gthelen@google.com: v4]
Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com
[akpm@linux-foundation.org: comment tweaks, struct initialization simplification]
Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613
Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com
Fixes:
|
|
|
Michal Hocko
|
8f175cf5c9 |
mm: fix do_pages_move status handling
Li Wang has reported that LTP move_pages04 test fails with the current
tree:
LTP move_pages04:
TFAIL : move_pages04.c:143: status[1] is EPERM, expected EFAULT
The test allocates an array of two pages, one is present while the other
is not (resp. backed by zero page) and it expects EFAULT for the second
page as the man page suggests. We are reporting EPERM which doesn't make
any sense and this is a result of a bug from cf5f16b23ec9 ("mm: unclutter
THP migration").
do_pages_move tries to handle as many pages in one batch as possible so we
queue all pages with the same node target together and that corresponds to
[start, i] range which is then used to update status array.
add_page_for_migration will correctly notice the zero (resp. !present)
page and returns with EFAULT which gets written to the status. But if
this is the last page in the array we do not update start and so the last
store_status after the loop will overwrite the range of the last batch
with NUMA_NO_NODE (which corresponds to EPERM).
Fix this by simply bailing out from the last flush if the pagelist is
empty as there is clearly nothing more to do.
Link: http://lkml.kernel.org/r/20180418121255.334-1-mhocko@kernel.org
Fixes: cf5f16b23ec9 ("mm: unclutter THP migration")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Li Wang <liwang@redhat.com>
Tested-by: Li Wang <liwang@redhat.com>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Jonathan Corbet
|
24844fd339 |
Merge branch 'mm-rst' into docs-next
Mike Rapoport says: These patches convert files in Documentation/vm to ReST format, add an initial index and link it to the top level documentation. There are no contents changes in the documentation, except few spelling fixes. The relatively large diffstat stems from the indentation and paragraph wrapping changes. I've tried to keep the formatting as consistent as possible, but I could miss some places that needed markup and add some markup where it was not necessary. [jc: significant conflicts in vm/hmm.rst] |
|
|
Mike Rapoport
|
ad56b738c5 |
docs/vm: rename documentation files to .rst
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
|
|
Tetsuo Handa
|
8e04944f0e |
mm,vmscan: Allow preallocating memory for register_shrinker().
syzbot is catching so many bugs triggered by commit
|
|
|
Vlastimil Babka
|
a9f2a846f0 |
mm, slab: reschedule cache_reap() on the same CPU
cache_reap() is initially scheduled in start_cpu_timer() via schedule_delayed_work_on(). But then the next iterations are scheduled via schedule_delayed_work(), i.e. using WORK_CPU_UNBOUND. Thus since commit |
|
|
Arnd Bergmann
|
453972283d |
mm/filemap.c: provide dummy filemap_page_mkwrite() for NOMMU
Building orangefs on MMU-less machines now results in a link error
because of the newly introduced use of the filemap_page_mkwrite()
function:
ERROR: "filemap_page_mkwrite" [fs/orangefs/orangefs.ko] undefined!
This adds a dummy version for it, similar to the existing
generic_file_mmap and generic_file_readonly_mmap stubs in the same file,
to avoid the link error without adding #ifdefs in each file system that
uses these.
Link: http://lkml.kernel.org/r/20180409105555.2439976-1-arnd@arndb.de
Fixes:
|
|
|
Michael S. Tsirkin
|
d081107867 |
mm/gup.c: document return value
__get_user_pages_fast handles errors differently from get_user_pages_fast: the former always returns the number of pages pinned, the later might return a negative error code. Link: http://lkml.kernel.org/r/1522962072-182137-6-git-send-email-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michael S. Tsirkin
|
c61611f709 |
get_user_pages_fast(): return -EFAULT on access_ok failure
get_user_pages_fast is supposed to be a faster drop-in equivalent of
get_user_pages. As such, callers expect it to return a negative return
code when passed an invalid address, and never expect it to return 0
when passed a positive number of pages, since its documentation says:
* Returns number of pages pinned. This may be fewer than the number
* requested. If nr_pages is 0 or negative, returns 0. If no pages
* were pinned, returns -errno.
When get_user_pages_fast fall back on get_user_pages this is exactly
what happens. Unfortunately the implementation is inconsistent: it
returns 0 if passed a kernel address, confusing callers: for example,
the following is pretty common but does not appear to do the right thing
with a kernel address:
ret = get_user_pages_fast(addr, 1, writeable, &page);
if (ret < 0)
return ret;
Change get_user_pages_fast to return -EFAULT when supplied a kernel
address to make it match expectations.
All callers have been audited for consistency with the documented
semantics.
Link: http://lkml.kernel.org/r/1522962072-182137-4-git-send-email-mst@redhat.com
Fixes:
|
|
|
Michael S. Tsirkin
|
09e35a4a1c |
mm/gup_benchmark: handle gup failures
Patch series "mm/get_user_pages_fast fixes, cleanups", v2. Turns out get_user_pages_fast and __get_user_pages_fast return different values on error when given a single page: __get_user_pages_fast returns 0. get_user_pages_fast returns either 0 or an error. Callers of get_user_pages_fast expect an error so fix it up to return an error consistently. Stress the difference between get_user_pages_fast and __get_user_pages_fast to make sure callers aren't confused. This patch (of 3): __gup_benchmark_ioctl does not handle the case where get_user_pages_fast fails: - a negative return code will cause a buffer overrun - returning with partial success will cause use of uninitialized memory. [akpm@linux-foundation.org: simplification] Link: http://lkml.kernel.org/r/1522962072-182137-3-git-send-email-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Matthew Wilcox
|
b93b016313 |
page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to the radix_tree_root. Rename the address_space ->page_tree to ->i_pages, since we don't really care that it's a tree. [willy@infradead.org: fix nds32, fs/dax.c] Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Acked-by: Jeff Layton <jlayton@redhat.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
6f84f8d158 |
xen, mm: allow deferred page initialization for xen pv domains
Juergen Gross noticed that commit
|
|
|
Michal Hocko
|
a4ff8e8620 |
mm: introduce MAP_FIXED_NOREPLACE
Patch series "mm: introduce MAP_FIXED_NOREPLACE", v2. This has started as a follow up discussion [3][4] resulting in the runtime failure caused by hardening patch [5] which removes MAP_FIXED from the elf loader because MAP_FIXED is inherently dangerous as it might silently clobber an existing underlying mapping (e.g. stack). The reason for the failure is that some architectures enforce an alignment for the given address hint without MAP_FIXED used (e.g. for shared or file backed mappings). One way around this would be excluding those archs which do alignment tricks from the hardening [6]. The patch is really trivial but it has been objected, rightfully so, that this screams for a more generic solution. We basically want a non-destructive MAP_FIXED. The first patch introduced MAP_FIXED_NOREPLACE which enforces the given address but unlike MAP_FIXED it fails with EEXIST if the given range conflicts with an existing one. The flag is introduced as a completely new one rather than a MAP_FIXED extension because of the backward compatibility. We really want a never-clobber semantic even on older kernels which do not recognize the flag. Unfortunately mmap sucks wrt flags evaluation because we do not EINVAL on unknown flags. On those kernels we would simply use the traditional hint based semantic so the caller can still get a different address (which sucks) but at least not silently corrupt an existing mapping. I do not see a good way around that. Except we won't export expose the new semantic to the userspace at all. It seems there are users who would like to have something like that. Jemalloc has been mentioned by Michael Ellerman [7] Florian Weimer has mentioned the following: : glibc ld.so currently maps DSOs without hints. This means that the kernel : will map right next to each other, and the offsets between them a completely : predictable. We would like to change that and supply a random address in a : window of the address space. If there is a conflict, we do not want the : kernel to pick a non-random address. Instead, we would try again with a : random address. John Hubbard has mentioned CUDA example : a) Searches /proc/<pid>/maps for a "suitable" region of available : VA space. "Suitable" generally means it has to have a base address : within a certain limited range (a particular device model might : have odd limitations, for example), it has to be large enough, and : alignment has to be large enough (again, various devices may have : constraints that lead us to do this). : : This is of course subject to races with other threads in the process. : : Let's say it finds a region starting at va. : : b) Next it does: : p = mmap(va, ...) : : *without* setting MAP_FIXED, of course (so va is just a hint), to : attempt to safely reserve that region. If p != va, then in most cases, : this is a failure (almost certainly due to another thread getting a : mapping from that region before we did), and so this layer now has to : call munmap(), before returning a "failure: retry" to upper layers. : : IMPROVEMENT: --> if instead, we could call this: : : p = mmap(va, ... MAP_FIXED_NOREPLACE ...) : : , then we could skip the munmap() call upon failure. This : is a small thing, but it is useful here. (Thanks to Piotr : Jaroszynski and Mark Hairgrove for helping me get that detail : exactly right, btw.) : : c) After that, CUDA suballocates from p, via: : : q = mmap(sub_region_start, ... MAP_FIXED ...) : : Interestingly enough, "freeing" is also done via MAP_FIXED, and : setting PROT_NONE to the subregion. Anyway, I just included (c) for : general interest. Atomic address range probing in the multithreaded programs in general sounds like an interesting thing to me. The second patch simply replaces MAP_FIXED use in elf loader by MAP_FIXED_NOREPLACE. I believe other places which rely on MAP_FIXED should follow. Actually real MAP_FIXED usages should be docummented properly and they should be more of an exception. [1] http://lkml.kernel.org/r/20171116101900.13621-1-mhocko@kernel.org [2] http://lkml.kernel.org/r/20171129144219.22867-1-mhocko@kernel.org [3] http://lkml.kernel.org/r/20171107162217.382cd754@canb.auug.org.au [4] http://lkml.kernel.org/r/1510048229.12079.7.camel@abdul.in.ibm.com [5] http://lkml.kernel.org/r/20171023082608.6167-1-mhocko@kernel.org [6] http://lkml.kernel.org/r/20171113094203.aofz2e7kueitk55y@dhcp22.suse.cz [7] http://lkml.kernel.org/r/87efp1w7vy.fsf@concordia.ellerman.id.au This patch (of 2): MAP_FIXED is used quite often to enforce mapping at the particular range. The main problem of this flag is, however, that it is inherently dangerous because it unmaps existing mappings covered by the requested range. This can cause silent memory corruptions. Some of them even with serious security implications. While the current semantic might be really desiderable in many cases there are others which would want to enforce the given range but rather see a failure than a silent memory corruption on a clashing range. Please note that there is no guarantee that a given range is obeyed by the mmap even when it is free - e.g. arch specific code is allowed to apply an alignment. Introduce a new MAP_FIXED_NOREPLACE flag for mmap to achieve this behavior. It has the same semantic as MAP_FIXED wrt. the given address request with a single exception that it fails with EEXIST if the requested address is already covered by an existing mapping. We still do rely on get_unmaped_area to handle all the arch specific MAP_FIXED treatment and check for a conflicting vma after it returns. The flag is introduced as a completely new one rather than a MAP_FIXED extension because of the backward compatibility. We really want a never-clobber semantic even on older kernels which do not recognize the flag. Unfortunately mmap sucks wrt. flags evaluation because we do not EINVAL on unknown flags. On those kernels we would simply use the traditional hint based semantic so the caller can still get a different address (which sucks) but at least not silently corrupt an existing mapping. I do not see a good way around that. [mpe@ellerman.id.au: fix whitespace] [fail on clashing range with EEXIST as per Florian Weimer] [set MAP_FIXED before round_hint_to_min as per Khalid Aziz] Link: http://lkml.kernel.org/r/20171213092550.2774-2-mhocko@kernel.org Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: Russell King - ARM Linux <linux@armlinux.org.uk> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Joel Stanley <joel@jms.id.au> Cc: Kees Cook <keescook@chromium.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Jason Evans <jasone@google.com> Cc: David Goldblatt <davidtgoldblatt@gmail.com> Cc: Edward Tomasz Napierała <trasz@FreeBSD.org> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Kees Cook
|
8f2af155b5 |
exec: pass stack rlimit into mm layout functions
Patch series "exec: Pin stack limit during exec". Attempts to solve problems with the stack limit changing during exec continue to be frustrated[1][2]. In addition to the specific issues around the Stack Clash family of flaws, Andy Lutomirski pointed out[3] other places during exec where the stack limit is used and is assumed to be unchanging. Given the many places it gets used and the fact that it can be manipulated/raced via setrlimit() and prlimit(), I think the only way to handle this is to move away from the "current" view of the stack limit and instead attach it to the bprm, and plumb this down into the functions that need to know the stack limits. This series implements the approach. [1] |
|
|
Andrey Konovalov
|
c3895391df |
kasan, slub: fix handling of kasan_slab_free hook
The kasan_slab_free hook's return value denotes whether the reuse of a slab object must be delayed (e.g. when the object is put into memory qurantine). The current way SLUB handles this hook is by ignoring its return value and hardcoding checks similar (but not exactly the same) to the ones performed in kasan_slab_free, which is prone to making mistakes. The main difference between the hardcoded checks and the ones in kasan_slab_free is whether we want to perform a free in case when an invalid-free or a double-free was detected (we don't). This patch changes the way SLUB handles this by: 1. taking into account the return value of kasan_slab_free for each of the objects, that are being freed; 2. reconstructing the freelist of objects to exclude the ones, whose reuse must be delayed. [andreyknvl@google.com: eliminate unnecessary branch in slab_free] Link: http://lkml.kernel.org/r/a62759a2545fddf69b0c034547212ca1eb1b3ce2.1520359686.git.andreyknvl@google.com Link: http://lkml.kernel.org/r/083f58501e54731203801d899632d76175868e97.1519400992.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Kostya Serebryany <kcc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Joonsoo Kim
|
b7d349c741 |
mm/thp: don't count ZONE_MOVABLE as the target for freepage reserving
There was a regression report for "mm/cma: manage the memory of the CMA
area by using the ZONE_MOVABLE" [1] and I think that it is related to
this problem. CMA patchset makes the system use one more zone
(ZONE_MOVABLE) and then increases min_free_kbytes. It reduces usable
memory and it could cause regression.
ZONE_MOVABLE only has movable pages so we don't need to keep enough
freepages to avoid or deal with fragmentation. So, don't count it.
This changes min_free_kbytes and thus min_watermark greatly if
ZONE_MOVABLE is used. It will make the user uses more memory.
System:
22GB ram, fakenuma, 2 nodes. 5 zones are used.
Before:
min_free_kbytes: 112640
zone_info (min_watermark):
Node 0, zone DMA
min 19
Node 0, zone DMA32
min 3778
Node 0, zone Normal
min 10191
Node 0, zone Movable
min 0
Node 0, zone Device
min 0
Node 1, zone DMA
min 0
Node 1, zone DMA32
min 0
Node 1, zone Normal
min 14043
Node 1, zone Movable
min 127
Node 1, zone Device
min 0
After:
min_free_kbytes: 90112
zone_info (min_watermark):
Node 0, zone DMA
min 15
Node 0, zone DMA32
min 3022
Node 0, zone Normal
min 8152
Node 0, zone Movable
min 0
Node 0, zone Device
min 0
Node 1, zone DMA
min 0
Node 1, zone DMA32
min 0
Node 1, zone Normal
min 11234
Node 1, zone Movable
min 102
Node 1, zone Device
min 0
[1] (lkml.kernel.org/r/20180102063528.GG30397%20()%20yexl-desktop)
Link: http://lkml.kernel.org/r/1522913236-15776-1-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Joonsoo Kim
|
1d47a3ec09 |
mm/cma: remove ALLOC_CMA
Now, all reserved pages for CMA region are belong to the ZONE_MOVABLE and it only serves for a request with GFP_HIGHMEM && GFP_MOVABLE. Therefore, we don't need to maintain ALLOC_CMA at all. Link: http://lkml.kernel.org/r/1512114786-5085-3-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Joonsoo Kim
|
bad8c6c0b1 |
mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE
Patch series "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE", v2. 0. History This patchset is the follow-up of the discussion about the "Introduce ZONE_CMA (v7)" [1]. Please reference it if more information is needed. 1. What does this patch do? This patch changes the management way for the memory of the CMA area in the MM subsystem. Currently the memory of the CMA area is managed by the zone where their pfn is belong to. However, this approach has some problems since MM subsystem doesn't have enough logic to handle the situation that different characteristic memories are in a single zone. To solve this issue, this patch try to manage all the memory of the CMA area by using the MOVABLE zone. In MM subsystem's point of view, characteristic of the memory on the MOVABLE zone and the memory of the CMA area are the same. So, managing the memory of the CMA area by using the MOVABLE zone will not have any problem. 2. Motivation There are some problems with current approach. See following. Although these problem would not be inherent and it could be fixed without this conception change, it requires many hooks addition in various code path and it would be intrusive to core MM and would be really error-prone. Therefore, I try to solve them with this new approach. Anyway, following is the problems of the current implementation. o CMA memory utilization First, following is the freepage calculation logic in MM. - For movable allocation: freepage = total freepage - For unmovable allocation: freepage = total freepage - CMA freepage Freepages on the CMA area is used after the normal freepages in the zone where the memory of the CMA area is belong to are exhausted. At that moment that the number of the normal freepages is zero, so - For movable allocation: freepage = total freepage = CMA freepage - For unmovable allocation: freepage = 0 If unmovable allocation comes at this moment, allocation request would fail to pass the watermark check and reclaim is started. After reclaim, there would exist the normal freepages so freepages on the CMA areas would not be used. FYI, there is another attempt [2] trying to solve this problem in lkml. And, as far as I know, Qualcomm also has out-of-tree solution for this problem. Useless reclaim: There is no logic to distinguish CMA pages in the reclaim path. Hence, CMA page is reclaimed even if the system just needs the page that can be usable for the kernel allocation. Atomic allocation failure: This is also related to the fallback allocation policy for the memory of the CMA area. Consider the situation that the number of the normal freepages is *zero* since the bunch of the movable allocation requests come. Kswapd would not be woken up due to following freepage calculation logic. - For movable allocation: freepage = total freepage = CMA freepage If atomic unmovable allocation request comes at this moment, it would fails due to following logic. - For unmovable allocation: freepage = total freepage - CMA freepage = 0 It was reported by Aneesh [3]. Useless compaction: Usual high-order allocation request is unmovable allocation request and it cannot be served from the memory of the CMA area. In compaction, migration scanner try to migrate the page in the CMA area and make high-order page there. As mentioned above, it cannot be usable for the unmovable allocation request so it's just waste. 3. Current approach and new approach Current approach is that the memory of the CMA area is managed by the zone where their pfn is belong to. However, these memory should be distinguishable since they have a strong limitation. So, they are marked as MIGRATE_CMA in pageblock flag and handled specially. However, as mentioned in section 2, the MM subsystem doesn't have enough logic to deal with this special pageblock so many problems raised. New approach is that the memory of the CMA area is managed by the MOVABLE zone. MM already have enough logic to deal with special zone like as HIGHMEM and MOVABLE zone. So, managing the memory of the CMA area by the MOVABLE zone just naturally work well because constraints for the memory of the CMA area that the memory should always be migratable is the same with the constraint for the MOVABLE zone. There is one side-effect for the usability of the memory of the CMA area. The use of MOVABLE zone is only allowed for a request with GFP_HIGHMEM && GFP_MOVABLE so now the memory of the CMA area is also only allowed for this gfp flag. Before this patchset, a request with GFP_MOVABLE can use them. IMO, It would not be a big issue since most of GFP_MOVABLE request also has GFP_HIGHMEM flag. For example, file cache page and anonymous page. However, file cache page for blockdev file is an exception. Request for it has no GFP_HIGHMEM flag. There is pros and cons on this exception. In my experience, blockdev file cache pages are one of the top reason that causes cma_alloc() to fail temporarily. So, we can get more guarantee of cma_alloc() success by discarding this case. Note that there is no change in admin POV since this patchset is just for internal implementation change in MM subsystem. Just one minor difference for admin is that the memory stat for CMA area will be printed in the MOVABLE zone. That's all. 4. Result Following is the experimental result related to utilization problem. 8 CPUs, 1024 MB, VIRTUAL MACHINE make -j16 <Before> CMA area: 0 MB 512 MB Elapsed-time: 92.4 186.5 pswpin: 82 18647 pswpout: 160 69839 <After> CMA : 0 MB 512 MB Elapsed-time: 93.1 93.4 pswpin: 84 46 pswpout: 183 92 akpm: "kernel test robot" reported a 26% improvement in vm-scalability.throughput: http://lkml.kernel.org/r/20180330012721.GA3845@yexl-desktop [1]: lkml.kernel.org/r/1491880640-9944-1-git-send-email-iamjoonsoo.kim@lge.com [2]: https://lkml.org/lkml/2014/10/15/623 [3]: http://www.spinics.net/lists/linux-mm/msg100562.html Link: http://lkml.kernel.org/r/1512114786-5085-2-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Joonsoo Kim
|
d3cda2337b |
mm/page_alloc: don't reserve ZONE_HIGHMEM for ZONE_MOVABLE request
Freepage on ZONE_HIGHMEM doesn't work for kernel memory so it's not that important to reserve. When ZONE_MOVABLE is used, this problem would theorectically cause to decrease usable memory for GFP_HIGHUSER_MOVABLE allocation request which is mainly used for page cache and anon page allocation. So, fix it by setting 0 to sysctl_lowmem_reserve_ratio[ZONE_HIGHMEM]. And, defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES - 1 size makes code complex. For example, if there is highmem system, following reserve ratio is activated for *NORMAL ZONE* which would be easyily misleading people. #ifdef CONFIG_HIGHMEM 32 #endif This patch also fixes this situation by defining sysctl_lowmem_reserve_ratio array by MAX_NR_ZONES and place "#ifdef" to right place. Link: http://lkml.kernel.org/r/1504672525-17915-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Tony Lindgren <tony@atomide.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michal Hocko
|
94723aafb9 |
mm: unclutter THP migration
THP migration is hacked into the generic migration with rather surprising semantic. The migration allocation callback is supposed to check whether the THP can be migrated at once and if that is not the case then it allocates a simple page to migrate. unmap_and_move then fixes that up by spliting the THP into small pages while moving the head page to the newly allocated order-0 page. Remaning pages are moved to the LRU list by split_huge_page. The same happens if the THP allocation fails. This is really ugly and error prone [1]. I also believe that split_huge_page to the LRU lists is inherently wrong because all tail pages are not migrated. Some callers will just work around that by retrying (e.g. memory hotplug). There are other pfn walkers which are simply broken though. e.g. madvise_inject_error will migrate head and then advances next pfn by the huge page size. do_move_page_to_node_array, queue_pages_range (migrate_pages, mbind), will simply split the THP before migration if the THP migration is not supported then falls back to single page migration but it doesn't handle tail pages if the THP migration path is not able to allocate a fresh THP so we end up with ENOMEM and fail the whole migration which is a questionable behavior. Page compaction doesn't try to migrate large pages so it should be immune. This patch tries to unclutter the situation by moving the special THP handling up to the migrate_pages layer where it actually belongs. We simply split the THP page into the existing list if unmap_and_move fails with ENOMEM and retry. So we will _always_ migrate all THP subpages and specific migrate_pages users do not have to deal with this case in a special way. [1] http://lkml.kernel.org/r/20171121021855.50525-1-zi.yan@sent.com Link: http://lkml.kernel.org/r/20180103082555.14592-4-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michal Hocko
|
666feb21a0 |
mm, migrate: remove reason argument from new_page_t
No allocation callback is using this argument anymore. new_page_node used to use this parameter to convey node_id resp. migration error up to move_pages code (do_move_page_to_node_array). The error status never made it into the final status field and we have a better way to communicate node id to the status field now. All other allocation callbacks simply ignored the argument so we can drop it finally. [mhocko@suse.com: fix migration callback] Link: http://lkml.kernel.org/r/20180105085259.GH2801@dhcp22.suse.cz [akpm@linux-foundation.org: fix alloc_misplaced_dst_page()] [mhocko@kernel.org: fix build] Link: http://lkml.kernel.org/r/20180103091134.GB11319@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20180103082555.14592-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michal Hocko
|
a49bd4d716 |
mm, numa: rework do_pages_move
Patch series "unclutter thp migration" Motivation: THP migration is hacked into the generic migration with rather surprising semantic. The migration allocation callback is supposed to check whether the THP can be migrated at once and if that is not the case then it allocates a simple page to migrate. unmap_and_move then fixes that up by splitting the THP into small pages while moving the head page to the newly allocated order-0 page. Remaining pages are moved to the LRU list by split_huge_page. The same happens if the THP allocation fails. This is really ugly and error prone [2]. I also believe that split_huge_page to the LRU lists is inherently wrong because all tail pages are not migrated. Some callers will just work around that by retrying (e.g. memory hotplug). There are other pfn walkers which are simply broken though. e.g. madvise_inject_error will migrate head and then advances next pfn by the huge page size. do_move_page_to_node_array, queue_pages_range (migrate_pages, mbind), will simply split the THP before migration if the THP migration is not supported then falls back to single page migration but it doesn't handle tail pages if the THP migration path is not able to allocate a fresh THP so we end up with ENOMEM and fail the whole migration which is a questionable behavior. Page compaction doesn't try to migrate large pages so it should be immune. The first patch reworks do_pages_move which relies on a very ugly calling semantic when the return status is pushed to the migration path via private pointer. It uses pre allocated fixed size batching to achieve that. We simply cannot do the same if a THP is to be split during the migration path which is done in the patch 3. Patch 2 is follow up cleanup which removes the mentioned return status calling convention ugliness. On a side note: There are some semantic issues I have encountered on the way when working on patch 1 but I am not addressing them here. E.g. trying to move THP tail pages will result in either success or EBUSY (the later one more likely once we isolate head from the LRU list). Hugetlb reports EACCESS on tail pages. Some errors are reported via status parameter but migration failures are not even though the original `reason' argument suggests there was an intention to do so. From a quick look into git history this never worked. I have tried to keep the semantic unchanged. Then there is a relatively minor thing that the page isolation might fail because of pages not being on the LRU - e.g. because they are sitting on the per-cpu LRU caches. Easily fixable. This patch (of 3): do_pages_move is supposed to move user defined memory (an array of addresses) to the user defined numa nodes (an array of nodes one for each address). The user provided status array then contains resulting numa node for each address or an error. The semantic of this function is little bit confusing because only some errors are reported back. Notably migrate_pages error is only reported via the return value. This patch doesn't try to address these semantic nuances but rather change the underlying implementation. Currently we are processing user input (which can be really large) in batches which are stored to a temporarily allocated page. Each address is resolved to its struct page and stored to page_to_node structure along with the requested target numa node. The array of these structures is then conveyed down the page migration path via private argument. new_page_node then finds the corresponding structure and allocates the proper target page. What is the problem with the current implementation and why to change it? Apart from being quite ugly it also doesn't cope with unexpected pages showing up on the migration list inside migrate_pages path. That doesn't happen currently but the follow up patch would like to make the thp migration code more clear and that would need to split a THP into the list for some cases. How does the new implementation work? Well, instead of batching into a fixed size array we simply batch all pages that should be migrated to the same node and isolate all of them into a linked list which doesn't require any additional storage. This should work reasonably well because page migration usually migrates larger ranges of memory to a specific node. So the common case should work equally well as the current implementation. Even if somebody constructs an input where the target numa nodes would be interleaved we shouldn't see a large performance impact because page migration alone doesn't really benefit from batching. mmap_sem batching for the lookup is quite questionable and isolate_lru_page which would benefit from batching is not using it even in the current implementation. Link: http://lkml.kernel.org/r/20180103082555.14592-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Zi Yan <zi.yan@cs.rutgers.edu> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Reale <ar@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Colin Ian King
|
bfc6b1cabc |
mm/swapfile.c: make pointer swap_avail_heads static
The pointer swap_avail_heads is local to the source and does not need to be in global scope, so make it static. Cleans up sparse warning: mm/swapfile.c:88:19: warning: symbol 'swap_avail_heads' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20180206215836.12366-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michal Hocko
|
4eaf431f6f |
memcg: fix per_node_info cleanup
syzbot has triggered a NULL ptr dereference when allocation fault
injection enforces a failure and alloc_mem_cgroup_per_node_info
initializes memcg->nodeinfo only half way through.
But __mem_cgroup_free still tries to free all per-node data and
dereferences pn->lruvec_stat_cpu unconditioanlly even if the specific
per-node data hasn't been initialized.
The bug is quite unlikely to hit because small allocations do not fail
and we would need quite some numa nodes to make struct
mem_cgroup_per_node large enough to cross the costly order.
Link: http://lkml.kernel.org/r/20180406100906.17790-1-mhocko@kernel.org
Reported-by: syzbot+8a5de3cce7cdc70e9ebe@syzkaller.appspotmail.com
Fixes:
|
|
|
Tom Abraham
|
a06ad633a3 |
swap: divide-by-zero when zero length swap file on ssd
Calling swapon() on a zero length swap file on SSD can lead to a divide-by-zero. Although creating such files isn't possible with mkswap and they woud be considered invalid, it would be better for the swapon code to be more robust and handle this condition gracefully (return -EINVAL). Especially since the fix is small and straightforward. To help with wear leveling on SSD, the swapon syscall calculates a random position in the swap file using modulo p->highest_bit, which is set to maxpages - 1 in read_swap_header. If the swap file is zero length, read_swap_header sets maxpages=1 and last_page=0, resulting in p->highest_bit=0 and we divide-by-zero when we modulo p->highest_bit in swapon syscall. This can be prevented by having read_swap_header return zero if last_page is zero. Link: http://lkml.kernel.org/r/5AC747C1020000A7001FA82C@prv-mh.provo.novell.com Signed-off-by: Thomas Abraham <tabraham@suse.com> Reported-by: <Mark.Landis@Teradata.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Johannes Weiner
|
e27be240df |
mm: memcg: make sure memory.events is uptodate when waking pollers
Commit |
|
|
Claudio Imbrenda
|
a38c015f31 |
mm/ksm.c: fix inconsistent accounting of zero pages
When using KSM with use_zero_pages, we replace anonymous pages
containing only zeroes with actual zero pages, which are not anonymous.
We need to do proper accounting of the mm counters, otherwise we will
get wrong values in /proc and a BUG message in dmesg when tearing down
the mm.
Link: http://lkml.kernel.org/r/1522931274-15552-1-git-send-email-imbrenda@linux.vnet.ibm.com
Fixes:
|
|
|
Matthew Wilcox
|
8a97ea546b |
mm/z3fold.c: use gfpflags_allow_blocking
We have a perfectly good macro to determine whether the gfp flags allow you to sleep or not; use it instead of trying to infer it. Link: http://lkml.kernel.org/r/20180408062206.GC16007@bombadil.infradead.org Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Xidong Wang
|
1ec6995d12 |
z3fold: fix memory leak
In z3fold_create_pool(), the memory allocated by __alloc_percpu() is not released on the error path that pool->compact_wq , which holds the return value of create_singlethread_workqueue(), is NULL. This will result in a memory leak bug. [akpm@linux-foundation.org: fix oops on kzalloc() failure, check __alloc_percpu() retval] Link: http://lkml.kernel.org/r/1522803111-29209-1-git-send-email-wangxidong_97@163.com Signed-off-by: Xidong Wang <wangxidong_97@163.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Michal Hocko
|
2a70f6a76b |
memcg, thp: do not invoke oom killer on thp charges
A THP memcg charge can trigger the oom killer since |
|
|
Ralph Campbell
|
07707125ae |
mm/migrate: properly preserve write attribute in special migrate entry
Use of pte_write(pte) is only valid for present pte, the common code which set the migration entry can be reach for both valid present pte and special swap entry (for device memory). Fix the code to use the mpfn value which properly handle both cases. On x86 this did not have any bad side effect because pte write bit is below PAGE_BIT_GLOBAL and thus special swap entry have it set to 0 which in turn means we were always creating read only special migration entry. So once migration did finish we always write protected the CPU page table entry (moreover this is only an issue when migrating from device memory to system memory). End effect is that CPU write access would fault again and restore write permission. This behaviour isn't too bad; it just burns CPU cycles by forcing CPU to take a second fault on write access. ie, double faulting the same address. There is no corruption or incorrect states (it behaves as a COWed page from a fork with a mapcount of 1). Link: http://lkml.kernel.org/r/20180402023506.12180-1-jglisse@redhat.com Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Mel Gorman
|
09a913a7a9 |
sched/numa: avoid trapping faults and attempting migration of file-backed dirty pages
change_pte_range is called from task work context to mark PTEs for
receiving NUMA faulting hints. If the marked pages are dirty then
migration may fail. Some filesystems cannot migrate dirty pages without
blocking so are skipped in MIGRATE_ASYNC mode which just wastes CPU.
Even when they can, it can be a waste of cycles when the pages are
shared forcing higher scan rates. This patch avoids marking shared
dirty pages for hinting faults but also will skip a migration if the
page was dirtied after the scanner updated a clean page.
This is most noticeable running the NASA Parallel Benchmark when backed
by btrfs, the default root filesystem for some distributions, but also
noticeable when using XFS.
The following are results from a 4-socket machine running a 4.16-rc4
kernel with some scheduler patches that are pending for the next merge
window.
4.16.0-rc4 4.16.0-rc4
schedtip-20180309 nodirty-v1
Time cg.D 459.07 ( 0.00%) 444.21 ( 3.24%)
Time ep.D 76.96 ( 0.00%) 77.69 ( -0.95%)
Time is.D 25.55 ( 0.00%) 27.85 ( -9.00%)
Time lu.D 601.58 ( 0.00%) 596.87 ( 0.78%)
Time mg.D 107.73 ( 0.00%) 108.22 ( -0.45%)
is.D regresses slightly in terms of absolute time but note that that
particular load varies quite a bit from run to run. The more relevant
observation is the total system CPU usage.
4.16.0-rc4 4.16.0-rc4
schedtip-20180309 nodirty-v1
User 71471.91 70627.04
System 11078.96 8256.13
Elapsed 661.66 632.74
That is a substantial drop in system CPU usage and overall the workload
completes faster. The NUMA balancing statistics are also interesting
NUMA base PTE updates 111407972 139848884
NUMA huge PMD updates 206506 264869
NUMA page range updates 217139044 275461812
NUMA hint faults 4300924 3719784
NUMA hint local faults 3012539 3416618
NUMA hint local percent 70 91
NUMA pages migrated 1517487 1358420
While more PTEs are scanned due to changes in what faults are gathered,
it's clear that a far higher percentage of faults are local as the bulk
of the remote hits were dirty pages that, in this case with btrfs, had
no chance of migrating.
The following is a comparison when using XFS as that is a more realistic
filesystem choice for a data partition
4.16.0-rc4 4.16.0-rc4
schedtip-20180309 nodirty-v1r47
Time cg.D 485.28 ( 0.00%) 442.62 ( 8.79%)
Time ep.D 77.68 ( 0.00%) 77.54 ( 0.18%)
Time is.D 26.44 ( 0.00%) 24.79 ( 6.24%)
Time lu.D 597.46 ( 0.00%) 597.11 ( 0.06%)
Time mg.D 142.65 ( 0.00%) 105.83 ( 25.81%)
That is a reasonable gain on two relatively long-lived workloads. While
not presented, there is also a substantial drop in system CPu usage and
the NUMA balancing stats show similar improvements in locality as btrfs
did.
Link: http://lkml.kernel.org/r/20180326094334.zserdec62gwmmfqf@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Tejun Heo
|
18be460eeb |
mm/hmm.c: remove superfluous RCU protection around radix tree lookup
hmm_devmem_find() requires rcu_read_lock_held() but there's nothing which actually uses the RCU protection. The only caller is hmm_devmem_pages_create() which already grabs the mutex and does superfluous rcu_read_lock/unlock() around the function. This doesn't add anything and just adds to confusion. Remove the RCU protection and open-code the radix tree lookup. If this needs to become more sophisticated in the future, let's add them back when necessary. Link: http://lkml.kernel.org/r/20180314194515.1661824-4-tj@kernel.org Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jérôme Glisse <jglisse@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
f88a1e90c6 |
mm/hmm: use device driver encoding for HMM pfn
Users of hmm_vma_fault() and hmm_vma_get_pfns() provide a flags array and pfn shift value allowing them to define their own encoding for HMM pfn that are fill inside the pfns array of the hmm_range struct. With this device driver can get pfn that match their own private encoding out of HMM without having to do any conversion. [rcampbell@nvidia.com: don't ignore specific pte fault flag in hmm_vma_fault()] Link: http://lkml.kernel.org/r/20180326213009.2460-2-jglisse@redhat.com [rcampbell@nvidia.com: clarify fault logic for device private memory] Link: http://lkml.kernel.org/r/20180326213009.2460-3-jglisse@redhat.com Link: http://lkml.kernel.org/r/20180323005527.758-16-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
2aee09d8c1 |
mm/hmm: change hmm_vma_fault() to allow write fault on page basis
This changes hmm_vma_fault() to not take a global write fault flag for a range but instead rely on caller to populate HMM pfns array with proper fault flag ie HMM_PFN_VALID if driver want read fault for that address or HMM_PFN_VALID and HMM_PFN_WRITE for write. Moreover by setting HMM_PFN_DEVICE_PRIVATE the device driver can ask for device private memory to be migrated back to system memory through page fault. This is more flexible API and it better reflects how device handles and reports fault. Link: http://lkml.kernel.org/r/20180323005527.758-15-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
53f5c3f489 |
mm/hmm: factor out pte and pmd handling to simplify hmm_vma_walk_pmd()
No functional change, just create one function to handle pmd and one to handle pte (hmm_vma_handle_pmd() and hmm_vma_handle_pte()). Link: http://lkml.kernel.org/r/20180323005527.758-14-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
33cd47dcbb |
mm/hmm: move hmm_pfns_clear() closer to where it is used
Move hmm_pfns_clear() closer to where it is used to make it clear it is not use by page table walkers. Link: http://lkml.kernel.org/r/20180323005527.758-13-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
b2744118a6 |
mm/hmm: rename HMM_PFN_DEVICE_UNADDRESSABLE to HMM_PFN_DEVICE_PRIVATE
Make naming consistent across code, DEVICE_PRIVATE is the name use outside HMM code so use that one. Link: http://lkml.kernel.org/r/20180323005527.758-12-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
5504ed2969 |
mm/hmm: do not differentiate between empty entry or missing directory
There is no point in differentiating between a range for which there is not even a directory (and thus entries) and empty entry (pte_none() or pmd_none() returns true). Simply drop the distinction ie remove HMM_PFN_EMPTY flag and merge now duplicate hmm_vma_walk_hole() and hmm_vma_walk_clear() functions. Link: http://lkml.kernel.org/r/20180323005527.758-11-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
855ce7d252 |
mm/hmm: cleanup special vma handling (VM_SPECIAL)
Special vma (one with any of the VM_SPECIAL flags) can not be access by device because there is no consistent model across device drivers on those vma and their backing memory. This patch directly use hmm_range struct for hmm_pfns_special() argument as it is always affecting the whole vma and thus the whole range. It also make behavior consistent after this patch both hmm_vma_fault() and hmm_vma_get_pfns() returns -EINVAL when facing such vma. Previously hmm_vma_fault() returned 0 and hmm_vma_get_pfns() return -EINVAL but both were filling the HMM pfn array with special entry. Link: http://lkml.kernel.org/r/20180323005527.758-10-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
ff05c0c6bb |
mm/hmm: use uint64_t for HMM pfn instead of defining hmm_pfn_t to ulong
All device driver we care about are using 64bits page table entry. In order to match this and to avoid useless define convert all HMM pfn to directly use uint64_t. It is a first step on the road to allow driver to directly use pfn value return by HMM (saving memory and CPU cycles use for conversion between the two). Link: http://lkml.kernel.org/r/20180323005527.758-9-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
86586a41b8 |
mm/hmm: remove HMM_PFN_READ flag and ignore peculiar architecture
Only peculiar architecture allow write without read thus assume that any valid pfn do allow for read. Note we do not care for write only because it does make sense with thing like atomic compare and exchange or any other operations that allow you to get the memory value through them. Link: http://lkml.kernel.org/r/20180323005527.758-8-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
08232a4544 |
mm/hmm: use struct for hmm_vma_fault(), hmm_vma_get_pfns() parameters
Both hmm_vma_fault() and hmm_vma_get_pfns() were taking a hmm_range struct as parameter and were initializing that struct with others of their parameters. Have caller of those function do this as they are likely to already do and only pass this struct to both function this shorten function signature and make it easier in the future to add new parameters by simply adding them to the structure. Link: http://lkml.kernel.org/r/20180323005527.758-7-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
c719547f03 |
mm/hmm: hmm_pfns_bad() was accessing wrong struct
The private field of mm_walk struct point to an hmm_vma_walk struct and not to the hmm_range struct desired. Fix to get proper struct pointer. Link: http://lkml.kernel.org/r/20180323005527.758-6-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Jérôme Glisse
|
c01cbba2aa |
mm/hmm: unregister mmu_notifier when last HMM client quit
This code was lost in translation at one point. This properly call mmu_notifier_unregister_no_release() once last user is gone. This fix the zombie mm_struct as without this patch we do not drop the refcount we have on it. Link: http://lkml.kernel.org/r/20180323005527.758-5-jglisse@redhat.com Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Ralph Campbell
|
e1401513c6 |
mm/hmm: HMM should have a callback before MM is destroyed
hmm_mirror_register() registers a callback for when the CPU pagetable is modified. Normally, the device driver will call hmm_mirror_unregister() when the process using the device is finished. However, if the process exits uncleanly, the struct_mm can be destroyed with no warning to the device driver. Link: http://lkml.kernel.org/r/20180323005527.758-4-jglisse@redhat.com Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Steven Rostedt
|
d51d1e6450 |
mm, vmscan, tracing: use pointer to reclaim_stat struct in trace event
The trace event trace_mm_vmscan_lru_shrink_inactive() currently has 12 parameters! Seven of them are from the reclaim_stat structure. This structure is currently local to mm/vmscan.c. By moving it to the global vmstat.h header, we can also reference it from the vmscan tracepoints. In moving it, it brings down the overhead of passing so many arguments to the trace event. In the future, we may limit the number of arguments that a trace event may pass (ideally just 6, but more realistically it may be 8). Before this patch, the code to call the trace event is this: 0f 83 aa fe ff ff jae ffffffff811e6261 <shrink_inactive_list+0x1e1> 48 8b 45 a0 mov -0x60(%rbp),%rax 45 8b 64 24 20 mov 0x20(%r12),%r12d 44 8b 6d d4 mov -0x2c(%rbp),%r13d 8b 4d d0 mov -0x30(%rbp),%ecx 44 8b 75 cc mov -0x34(%rbp),%r14d 44 8b 7d c8 mov -0x38(%rbp),%r15d 48 89 45 90 mov %rax,-0x70(%rbp) 8b 83 b8 fe ff ff mov -0x148(%rbx),%eax 8b 55 c0 mov -0x40(%rbp),%edx 8b 7d c4 mov -0x3c(%rbp),%edi 8b 75 b8 mov -0x48(%rbp),%esi 89 45 80 mov %eax,-0x80(%rbp) 65 ff 05 e4 f7 e2 7e incl %gs:0x7ee2f7e4(%rip) # 15bd0 <__preempt_count> 48 8b 05 75 5b 13 01 mov 0x1135b75(%rip),%rax # ffffffff8231bf68 <__tracepoint_mm_vmscan_lru_shrink_inactive+0x28> 48 85 c0 test %rax,%rax 74 72 je ffffffff811e646a <shrink_inactive_list+0x3ea> 48 89 c3 mov %rax,%rbx 4c 8b 10 mov (%rax),%r10 89 f8 mov %edi,%eax 48 89 85 68 ff ff ff mov %rax,-0x98(%rbp) 89 f0 mov %esi,%eax 48 89 85 60 ff ff ff mov %rax,-0xa0(%rbp) 89 c8 mov %ecx,%eax 48 89 85 78 ff ff ff mov %rax,-0x88(%rbp) 89 d0 mov %edx,%eax 48 89 85 70 ff ff ff mov %rax,-0x90(%rbp) 8b 45 8c mov -0x74(%rbp),%eax 48 8b 7b 08 mov 0x8(%rbx),%rdi 48 83 c3 18 add $0x18,%rbx 50 push %rax 41 54 push %r12 41 55 push %r13 ff b5 78 ff ff ff pushq -0x88(%rbp) 41 56 push %r14 41 57 push %r15 ff b5 70 ff ff ff pushq -0x90(%rbp) 4c 8b 8d 68 ff ff ff mov -0x98(%rbp),%r9 4c 8b 85 60 ff ff ff mov -0xa0(%rbp),%r8 48 8b 4d 98 mov -0x68(%rbp),%rcx 48 8b 55 90 mov -0x70(%rbp),%rdx 8b 75 80 mov -0x80(%rbp),%esi 41 ff d2 callq *%r10 After the patch: 0f 83 a8 fe ff ff jae ffffffff811e626d <shrink_inactive_list+0x1cd> 8b 9b b8 fe ff ff mov -0x148(%rbx),%ebx 45 8b 64 24 20 mov 0x20(%r12),%r12d 4c 8b 6d a0 mov -0x60(%rbp),%r13 65 ff 05 f5 f7 e2 7e incl %gs:0x7ee2f7f5(%rip) # 15bd0 <__preempt_count> 4c 8b 35 86 5b 13 01 mov 0x1135b86(%rip),%r14 # ffffffff8231bf68 <__tracepoint_mm_vmscan_lru_shrink_inactive+0x28> 4d 85 f6 test %r14,%r14 74 2a je ffffffff811e6411 <shrink_inactive_list+0x371> 49 8b 06 mov (%r14),%rax 8b 4d 8c mov -0x74(%rbp),%ecx 49 8b 7e 08 mov 0x8(%r14),%rdi 49 83 c6 18 add $0x18,%r14 4c 89 ea mov %r13,%rdx 45 89 e1 mov %r12d,%r9d 4c 8d 45 b8 lea -0x48(%rbp),%r8 89 de mov %ebx,%esi 51 push %rcx 48 8b 4d 98 mov -0x68(%rbp),%rcx ff d0 callq *%rax Link: http://lkml.kernel.org/r/2559d7cb-ec60-1200-2362-04fa34fd02bb@fb.com Link: http://lkml.kernel.org/r/20180322121003.4177af15@gandalf.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reported-by: Alexei Starovoitov <ast@fb.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexei Starovoitov <ast@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Andrey Ryabinin
|
e3c1ac586c |
mm/vmscan: don't mess with pgdat->flags in memcg reclaim
memcg reclaim may alter pgdat->flags based on the state of LRU lists in
cgroup and its children. PGDAT_WRITEBACK may force kswapd to sleep
congested_wait(), PGDAT_DIRTY may force kswapd to writeback filesystem
pages. But the worst here is PGDAT_CONGESTED, since it may force all
direct reclaims to stall in wait_iff_congested(). Note that only kswapd
have powers to clear any of these bits. This might just never happen if
cgroup limits configured that way. So all direct reclaims will stall as
long as we have some congested bdi in the system.
Leave all pgdat->flags manipulations to kswapd. kswapd scans the whole
pgdat, only kswapd can clear pgdat->flags once node is balanced, thus
it's reasonable to leave all decisions about node state to kswapd.
Why only kswapd? Why not allow to global direct reclaim change these
flags? It is because currently only kswapd can clear these flags. I'm
less worried about the case when PGDAT_CONGESTED falsely not set, and
more worried about the case when it falsely set. If direct reclaimer
sets PGDAT_CONGESTED, do we have guarantee that after the congestion
problem is sorted out, kswapd will be woken up and clear the flag? It
seems like there is no such guarantee. E.g. direct reclaimers may
eventually balance pgdat and kswapd simply won't wake up (see
wakeup_kswapd()).
Moving pgdat->flags manipulation to kswapd, means that cgroup2 recalim
now loses its congestion throttling mechanism. Add per-cgroup
congestion state and throttle cgroup2 reclaimers if memcg is in
congestion state.
Currently there is no need in per-cgroup PGDAT_WRITEBACK and PGDAT_DIRTY
bits since they alter only kswapd behavior.
The problem could be easily demonstrated by creating heavy congestion in
one cgroup:
echo "+memory" > /sys/fs/cgroup/cgroup.subtree_control
mkdir -p /sys/fs/cgroup/congester
echo 512M > /sys/fs/cgroup/congester/memory.max
echo $$ > /sys/fs/cgroup/congester/cgroup.procs
/* generate a lot of diry data on slow HDD */
while true; do dd if=/dev/zero of=/mnt/sdb/zeroes bs=1M count=1024; done &
....
while true; do dd if=/dev/zero of=/mnt/sdb/zeroes bs=1M count=1024; done &
and some job in another cgroup:
mkdir /sys/fs/cgroup/victim
echo 128M > /sys/fs/cgroup/victim/memory.max
# time cat /dev/sda > /dev/null
real 10m15.054s
user 0m0.487s
sys 1m8.505s
According to the tracepoint in wait_iff_congested(), the 'cat' spent 50%
of the time sleeping there.
With the patch, cat don't waste time anymore:
# time cat /dev/sda > /dev/null
real 5m32.911s
user 0m0.411s
sys 0m56.664s
[aryabinin@virtuozzo.com: congestion state should be per-node]
Link: http://lkml.kernel.org/r/20180406135215.10057-1-aryabinin@virtuozzo.com
[ayabinin@virtuozzo.com: make congestion state per-cgroup-per-node instead of just per-cgroup[
Link: http://lkml.kernel.org/r/20180406180254.8970-2-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20180323152029.11084-5-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Andrey Ryabinin
|
d108c7721f |
mm/vmscan: don't change pgdat state on base of a single LRU list state
We have separate LRU list for each memory cgroup. Memory reclaim iterates over cgroups and calls shrink_inactive_list() every inactive LRU list. Based on the state of a single LRU shrink_inactive_list() may flag the whole node as dirty,congested or under writeback. This is obviously wrong and hurtful. It's especially hurtful when we have possibly small congested cgroup in system. Than *all* direct reclaims waste time by sleeping in wait_iff_congested(). And the more memcgs in the system we have the longer memory allocation stall is, because wait_iff_congested() called on each lru-list scan. Sum reclaim stats across all visited LRUs on node and flag node as dirty, congested or under writeback based on that sum. Also call congestion_wait(), wait_iff_congested() once per pgdat scan, instead of once per lru-list scan. This only fixes the problem for global reclaim case. Per-cgroup reclaim may alter global pgdat flags too, which is wrong. But that is separate issue and will be addressed in the next patch. This change will not have any effect on a systems with all workload concentrated in a single cgroup. [aryabinin@virtuozzo.com: check nr_writeback against all nr_taken, not just file] Link: http://lkml.kernel.org/r/20180406180254.8970-1-aryabinin@virtuozzo.com Link: http://lkml.kernel.org/r/20180323152029.11084-4-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Andrey Ryabinin
|
c4fd4fa580 |
mm/vmscan: remove redundant current_may_throttle() check
Only kswapd can have non-zero nr_immediate, and current_may_throttle() is always true for kswapd (PF_LESS_THROTTLE bit is never set) thus it's enough to check stat.nr_immediate only. Link: http://lkml.kernel.org/r/20180315164553.17856-4-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Andrey Ryabinin
|
894befec4d |
mm/vmscan: update stale comments
Update some comments that became stale since transiton from per-zone to per-node reclaim. Link: http://lkml.kernel.org/r/20180315164553.17856-2-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Roman Gushchin
|
d79f7aa496 |
mm: treat indirectly reclaimable memory as free in overcommit logic
Indirectly reclaimable memory can consume a significant part of total
memory and it's actually reclaimable (it will be released under actual
memory pressure).
So, the overcommit logic should treat it as free.
Otherwise, it's possible to cause random system-wide memory allocation
failures by consuming a significant amount of memory by indirectly
reclaimable memory, e.g. dentry external names.
If overcommit policy GUESS is used, it might be used for denial of
service attack under some conditions.
The following program illustrates the approach. It causes the kernel to
allocate an unreclaimable kmalloc-256 chunk for each stat() call, so
that at some point the overcommit logic may start blocking large
allocation system-wide.
int main()
{
char buf[256];
unsigned long i;
struct stat statbuf;
buf[0] = '/';
for (i = 1; i < sizeof(buf); i++)
buf[i] = '_';
for (i = 0; 1; i++) {
sprintf(&buf[248], "%8lu", i);
stat(buf, &statbuf);
}
return 0;
}
This patch in combination with related indirectly reclaimable memory
patches closes this issue.
Link: http://lkml.kernel.org/r/20180313130041.8078-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Roman Gushchin
|
034ebf65c3 |
mm: treat indirectly reclaimable memory as available in MemAvailable
Adjust /proc/meminfo MemAvailable calculation by adding the amount of indirectly reclaimable memory (rounded to the PAGE_SIZE). Link: http://lkml.kernel.org/r/20180305133743.12746-4-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Roman Gushchin
|
eb59254608 |
mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES
Patch series "indirectly reclaimable memory", v2. This patchset introduces the concept of indirectly reclaimable memory and applies it to fix the issue of when a big number of dentries with external names can significantly affect the MemAvailable value. This patch (of 3): Introduce a concept of indirectly reclaimable memory and adds the corresponding memory counter and /proc/vmstat item. Indirectly reclaimable memory is any sort of memory, used by the kernel (except of reclaimable slabs), which is actually reclaimable, i.e. will be released under memory pressure. The counter is in bytes, as it's not always possible to count such objects in pages. The name contains BYTES by analogy to NR_KERNEL_STACK_KB. Link: http://lkml.kernel.org/r/20180305133743.12746-2-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Linus Torvalds
|
49a695ba72 |
powerpc updates for 4.17
Notable changes:
- Support for 4PB user address space on 64-bit, opt-in via mmap().
- Removal of POWER4 support, which was accidentally broken in 2016 and no one
noticed, and blocked use of some modern instructions.
- Workarounds so that the hypervisor can enable Transactional Memory on Power9.
- A series to disable the DAWR (Data Address Watchpoint Register) on Power9.
- More information displayed in the meltdown/spectre_v1/v2 sysfs files.
- A vpermxor (Power8 Altivec) implementation for the raid6 Q Syndrome.
- A big series to make the allocation of our pacas (per cpu area), kernel page
tables, and per-cpu stacks NUMA aware when using the Radix MMU on Power9.
And as usual many fixes, reworks and cleanups.
Thanks to:
Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy, Alistair Popple, Andy
Shevchenko, Aneesh Kumar K.V, Anshuman Khandual, Balbir Singh, Benjamin
Herrenschmidt, Christophe Leroy, Christophe Lombard, Cyril Bur, Daniel Axtens,
Dave Young, Finn Thain, Frederic Barrat, Gustavo Romero, Horia Geantă,
Jonathan Neuschäfer, Kees Cook, Larry Finger, Laurent Dufour, Laurent Vivier,
Logan Gunthorpe, Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus
Elfring, Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de
Oliveira, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher Boessenkool,
Simon Guo, Simon Horman, Stewart Smith, Sukadev Bhattiprolu, Suraj Jitindar
Singh, Thiago Jung Bauermann, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant
Hegde, Wei Yongjun.
-----BEGIN PGP SIGNATURE-----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=HAB1
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- Support for 4PB user address space on 64-bit, opt-in via mmap().
- Removal of POWER4 support, which was accidentally broken in 2016
and no one noticed, and blocked use of some modern instructions.
- Workarounds so that the hypervisor can enable Transactional Memory
on Power9.
- A series to disable the DAWR (Data Address Watchpoint Register) on
Power9.
- More information displayed in the meltdown/spectre_v1/v2 sysfs
files.
- A vpermxor (Power8 Altivec) implementation for the raid6 Q
Syndrome.
- A big series to make the allocation of our pacas (per cpu area),
kernel page tables, and per-cpu stacks NUMA aware when using the
Radix MMU on Power9.
And as usual many fixes, reworks and cleanups.
Thanks to: Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy,
Alistair Popple, Andy Shevchenko, Aneesh Kumar K.V, Anshuman Khandual,
Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
Lombard, Cyril Bur, Daniel Axtens, Dave Young, Finn Thain, Frederic
Barrat, Gustavo Romero, Horia Geantă, Jonathan Neuschäfer, Kees Cook,
Larry Finger, Laurent Dufour, Laurent Vivier, Logan Gunthorpe,
Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus Elfring,
Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de Oliveira,
Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher
Boessenkool, Simon Guo, Simon Horman, Stewart Smith, Sukadev
Bhattiprolu, Suraj Jitindar Singh, Thiago Jung Bauermann, Vaibhav
Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wei Yongjun"
* tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (207 commits)
powerpc/64s/idle: Fix restore of AMOR on POWER9 after deep sleep
powerpc/64s: Fix POWER9 DD2.2 and above in cputable features
powerpc/64s: Fix pkey support in dt_cpu_ftrs, add CPU_FTR_PKEY bit
powerpc/64s: Fix dt_cpu_ftrs to have restore_cpu clear unwanted LPCR bits
Revert "powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead"
powerpc: iomap.c: introduce io{read|write}64_{lo_hi|hi_lo}
powerpc: io.h: move iomap.h include so that it can use readq/writeq defs
cxl: Fix possible deadlock when processing page faults from cxllib
powerpc/hw_breakpoint: Only disable hw breakpoint if cpu supports it
powerpc/mm/radix: Update command line parsing for disable_radix
powerpc/mm/radix: Parse disable_radix commandline correctly.
powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
powerpc/mm/keys: Update documentation and remove unnecessary check
powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead
powerpc/64s/idle: Consolidate power9_offline_stop()/power9_idle_stop()
powerpc/powernv: Always stop secondaries before reboot/shutdown
powerpc: hard disable irqs in smp_send_stop loop
powerpc: use NMI IPI for smp_send_stop
powerpc/powernv: Fix SMT4 forcing idle code
...
|
|
|
Linus Torvalds
|
3b54765cca |
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton: - a few misc things - ocfs2 updates - the v9fs maintainers have been missing for a long time. I've taken over v9fs patch slinging. - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (116 commits) mm,oom_reaper: check for MMF_OOM_SKIP before complaining mm/ksm: fix interaction with THP mm/memblock.c: cast constant ULLONG_MAX to phys_addr_t headers: untangle kmemleak.h from mm.h include/linux/mmdebug.h: make VM_WARN* non-rvals mm/page_isolation.c: make start_isolate_page_range() fail if already isolated mm: change return type to vm_fault_t mm, oom: remove 3% bonus for CAP_SYS_ADMIN processes mm, page_alloc: wakeup kcompactd even if kswapd cannot free more memory kernel/fork.c: detect early free of a live mm mm: make counting of list_lru_one::nr_items lockless mm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static block_invalidatepage(): only release page if the full page was invalidated mm: kernel-doc: add missing parameter descriptions mm/swap.c: remove @cold parameter description for release_pages() mm/nommu: remove description of alloc_vm_area zram: drop max_zpage_size and use zs_huge_class_size() zsmalloc: introduce zs_huge_class_size() mm: fix races between swapoff and flush dcache fs/direct-io.c: minor cleanups in do_blockdev_direct_IO ... |
|
|
Tetsuo Handa
|
97b1255cb2 |
mm,oom_reaper: check for MMF_OOM_SKIP before complaining
I got "oom_reaper: unable to reap pid:" messages when the victim thread was blocked inside free_pgtables() (which occurred after returning from unmap_vmas() and setting MMF_OOM_SKIP). We don't need to complain when exit_mmap() already set MMF_OOM_SKIP. Killed process 7558 (a.out) total-vm:4176kB, anon-rss:84kB, file-rss:0kB, shmem-rss:0kB oom_reaper: unable to reap pid:7558 (a.out) a.out D13272 7558 6931 0x00100084 Call Trace: schedule+0x2d/0x80 rwsem_down_write_failed+0x2bb/0x440 call_rwsem_down_write_failed+0x13/0x20 down_write+0x49/0x60 unlink_file_vma+0x28/0x50 free_pgtables+0x36/0x100 exit_mmap+0xbb/0x180 mmput+0x50/0x110 copy_process.part.41+0xb61/0x1fe0 _do_fork+0xe6/0x560 do_syscall_64+0x74/0x230 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Link: http://lkml.kernel.org/r/201803221946.DHG65638.VFJHFtOSQLOMOF@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Claudio Imbrenda
|
77da2ba064 |
mm/ksm: fix interaction with THP
This patch fixes a corner case for KSM. When two pages belong or belonged to the same transparent hugepage, and they should be merged, KSM fails to split the page, and therefore no merging happens. This bug can be reproduced by: * making sure ksm is running (in case disabling ksmtuned) * enabling transparent hugepages * allocating a THP-aligned 1-THP-sized buffer e.g. on amd64: posix_memalign(&p, 1<<21, 1<<21) * filling it with the same values e.g. memset(p, 42, 1<<21) * performing madvise to make it mergeable e.g. madvise(p, 1<<21, MADV_MERGEABLE) * waiting for KSM to perform a few scans The expected outcome is that the all the pages get merged (1 shared and the rest sharing); the actual outcome is that no pages get merged (1 unshared and the rest volatile) The reason of this behaviour is that we increase the reference count once for both pages we want to merge, but if they belong to the same hugepage (or compound page), the reference counter used in both cases is the one of the head of the compound page. This means that split_huge_page will find a value of the reference counter too high and will fail. This patch solves this problem by testing if the two pages to merge belong to the same hugepage when attempting to merge them. If so, the hugepage is split safely. This means that the hugepage is not split if not necessary. Link: http://lkml.kernel.org/r/1521548069-24758-1-git-send-email-imbrenda@linux.vnet.ibm.com Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Co-authored-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Stefan Agner
|
644d87dccd |
mm/memblock.c: cast constant ULLONG_MAX to phys_addr_t
This fixes a warning shown when phys_addr_t is 32-bit int when compiling
with clang:
mm/memblock.c:927:15: warning: implicit conversion from 'unsigned long long'
to 'phys_addr_t' (aka 'unsigned int') changes value from
18446744073709551615 to 4294967295 [-Wconstant-conversion]
r->base : ULLONG_MAX;
^~~~~~~~~~
./include/linux/kernel.h:30:21: note: expanded from macro 'ULLONG_MAX'
#define ULLONG_MAX (~0ULL)
^~~~~
Link: http://lkml.kernel.org/r/20180319005645.29051-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Randy Dunlap
|
514c603249 |
headers: untangle kmemleak.h from mm.h
Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious reason. It looks like it's only a convenience, so remove kmemleak.h from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that don't already #include it. Also remove <linux/kmemleak.h> from source files that do not use it. This is tested on i386 allmodconfig and x86_64 allmodconfig. It would be good to run it through the 0day bot for other $ARCHes. I have neither the horsepower nor the storage space for the other $ARCHes. Update: This patch has been extensively build-tested by both the 0day bot & kisskb/ozlabs build farms. Both of them reported 2 build failures for which patches are included here (in v2). [ slab.h is the second most used header file after module.h; kernel.h is right there with slab.h. There could be some minor error in the counting due to some #includes having comments after them and I didn't combine all of those. ] [akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr] Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org Link: http://kisskb.ellerman.id.au/kisskb/head/13396/ Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Reported-by: Michael Ellerman <mpe@ellerman.id.au> [2 build failures] Reported-by: Fengguang Wu <fengguang.wu@intel.com> [2 build failures] Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Wei Yongjun <weiyongjun1@huawei.com> Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Mike Kravetz
|
2c7452a075 |
mm/page_isolation.c: make start_isolate_page_range() fail if already isolated
start_isolate_page_range() is used to set the migrate type of a set of pageblocks to MIGRATE_ISOLATE while attempting to start a migration operation. It assumes that only one thread is calling it for the specified range. This routine is used by CMA, memory hotplug and gigantic huge pages. Each of these users synchronize access to the range within their subsystem. However, two subsystems (CMA and gigantic huge pages for example) could attempt operations on the same range. If this happens, one thread may 'undo' the work another thread is doing. This can result in pageblocks being incorrectly left marked as MIGRATE_ISOLATE and therefore not available for page allocation. What is ideally needed is a way to synchronize access to a set of pageblocks that are undergoing isolation and migration. The only thing we know about these pageblocks is that they are all in the same zone. A per-node mutex is too coarse as we want to allow multiple operations on different ranges within the same zone concurrently. Instead, we will use the migration type of the pageblocks themselves as a form of synchronization. start_isolate_page_range sets the migration type on a set of page- blocks going in order from the one associated with the smallest pfn to the largest pfn. The zone lock is acquired to check and set the migration type. When going through the list of pageblocks check if MIGRATE_ISOLATE is already set. If so, this indicates another thread is working on this pageblock. We know exactly which pageblocks we set, so clean up by undo those and return -EBUSY. This allows start_isolate_page_range to serve as a synchronization mechanism and will allow for more general use of callers making use of these interfaces. Update comments in alloc_contig_range to reflect this new functionality. Each CPU holds the associated zone lock to modify or examine the migration type of a pageblock. And, it will only examine/update a single pageblock per lock acquire/release cycle. Link: http://lkml.kernel.org/r/20180309224731.16978-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Rientjes
|
d46078b288 |
mm, oom: remove 3% bonus for CAP_SYS_ADMIN processes
Since the 2.6 kernel, the oom killer has slightly biased away from CAP_SYS_ADMIN processes by discounting some of its memory usage in comparison to other processes. This has always been implicit and nothing exactly relies on the behavior. Gaurav notices that __task_cred() can dereference a potentially freed pointer if the task under consideration is exiting because a reference to the task_struct is not held. Remove the CAP_SYS_ADMIN bias so that all processes are treated equally. If any CAP_SYS_ADMIN process would like to be biased against, it is always allowed to adjust /proc/pid/oom_score_adj. Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803071548510.6996@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Gaurav Kohli <gkohli@codeaurora.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Rientjes
|
5ecd9d403a |
mm, page_alloc: wakeup kcompactd even if kswapd cannot free more memory
Kswapd will not wakeup if per-zone watermarks are not failing or if too many previous attempts at background reclaim have failed. This can be true if there is a lot of free memory available. For high- order allocations, kswapd is responsible for waking up kcompactd for background compaction. If the zone is not below its watermarks or reclaim has recently failed (lots of free memory, nothing left to reclaim), kcompactd does not get woken up. When __GFP_DIRECT_RECLAIM is not allowed, allow kcompactd to still be woken up even if kswapd will not reclaim. This allows high-order allocations, such as thp, to still trigger background compaction even when the zone has an abundance of free memory. Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803111659420.209721@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Kirill Tkhai
|
0c7c1bed7e |
mm: make counting of list_lru_one::nr_items lockless
During the reclaiming slab of a memcg, shrink_slab iterates over all registered shrinkers in the system, and tries to count and consume objects related to the cgroup. In case of memory pressure, this behaves bad: I observe high system time and time spent in list_lru_count_one() for many processes on RHEL7 kernel. This patch makes list_lru_node::memcg_lrus rcu protected, that allows to skip taking spinlock in list_lru_count_one(). Shakeel Butt with the patch observes significant perf graph change. He says: ======================================================================== Setup: running a fork-bomb in a memcg of 200MiB on a 8GiB and 4 vcpu VM and recording the trace with 'perf record -g -a'. The trace without the patch: + 34.19% fb.sh [kernel.kallsyms] [k] queued_spin_lock_slowpath + 30.77% fb.sh [kernel.kallsyms] [k] _raw_spin_lock + 3.53% fb.sh [kernel.kallsyms] [k] list_lru_count_one + 2.26% fb.sh [kernel.kallsyms] [k] super_cache_count + 1.68% fb.sh [kernel.kallsyms] [k] shrink_slab + 0.59% fb.sh [kernel.kallsyms] [k] down_read_trylock + 0.48% fb.sh [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore + 0.38% fb.sh [kernel.kallsyms] [k] shrink_node_memcg + 0.32% fb.sh [kernel.kallsyms] [k] queue_work_on + 0.26% fb.sh [kernel.kallsyms] [k] count_shadow_nodes With the patch: + 0.16% swapper [kernel.kallsyms] [k] default_idle + 0.13% oom_reaper [kernel.kallsyms] [k] mutex_spin_on_owner + 0.05% perf [kernel.kallsyms] [k] copy_user_generic_string + 0.05% init.real [kernel.kallsyms] [k] wait_consider_task + 0.05% kworker/0:0 [kernel.kallsyms] [k] finish_task_switch + 0.04% kworker/2:1 [kernel.kallsyms] [k] finish_task_switch + 0.04% kworker/3:1 [kernel.kallsyms] [k] finish_task_switch + 0.04% kworker/1:0 [kernel.kallsyms] [k] finish_task_switch + 0.03% binary [kernel.kallsyms] [k] copy_page ======================================================================== Thanks Shakeel for the testing. [ktkhai@virtuozzo.com: v2] Link: http://lkml.kernel.org/r/151203869520.3915.2587549826865799173.stgit@localhost.localdomain Link: http://lkml.kernel.org/r/150583358557.26700.8490036563698102569.stgit@localhost.localdomain Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Shakeel Butt <shakeelb@google.com> Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Colin Ian King
|
f5c754d63d |
mm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static
The bool enable_vma_readahead and swap_vma_readahead() are local to the source and do not need to be in global scope, so make them static. Cleans up sparse warnings: mm/swap_state.c:41:6: warning: symbol 'enable_vma_readahead' was not declared. Should it be static? mm/swap_state.c:742:13: warning: symbol 'swap_vma_readahead' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20180223164852.5159-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Mike Rapoport
|
e8b098fc57 |
mm: kernel-doc: add missing parameter descriptions
Link: http://lkml.kernel.org/r/1519585191-10180-4-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Mike Rapoport
|
002843de36 |
mm/swap.c: remove @cold parameter description for release_pages()
The 'cold' parameter was removed from release_pages function by commit
|
|
|
Mike Rapoport
|
e48e3c590a |
mm/nommu: remove description of alloc_vm_area
The alloc_mm_area in nommu is a stub, but its description states it allocates kernel address space. Remove the description to make the code and the documentation agree. Link: http://lkml.kernel.org/r/1519585191-10180-2-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Sergey Senozhatsky
|
010b495e2f |
zsmalloc: introduce zs_huge_class_size()
Patch series "zsmalloc/zram: drop zram's max_zpage_size", v3. ZRAM's max_zpage_size is a bad thing. It forces zsmalloc to store normal objects as huge ones, which results in bigger zsmalloc memory usage. Drop it and use actual zsmalloc huge-class value when decide if the object is huge or not. This patch (of 2): Not every object can be share its zspage with other objects, e.g. when the object is as big as zspage or nearly as big a zspage. For such objects zsmalloc has a so called huge class - every object which belongs to huge class consumes the entire zspage (which consists of a physical page). On x86_64, PAGE_SHIFT 12 box, the first non-huge class size is 3264, so starting down from size 3264, objects can share page(-s) and thus minimize memory wastage. ZRAM, however, has its own statically defined watermark for huge objects, namely "3 * PAGE_SIZE / 4 = 3072", and forcibly stores every object larger than this watermark (3072) as a PAGE_SIZE object, in other words, to a huge class, while zsmalloc can keep some of those objects in non-huge classes. This results in increased memory consumption. zsmalloc knows better if the object is huge or not. Introduce zs_huge_class_size() function which tells if the given object can be stored in one of non-huge classes or not. This will let us to drop ZRAM's huge object watermark and fully rely on zsmalloc when we decide if the object is huge. [sergey.senozhatsky.work@gmail.com: add pool param to zs_huge_class_size()] Link: http://lkml.kernel.org/r/20180314081833.1096-2-sergey.senozhatsky@gmail.com Link: http://lkml.kernel.org/r/20180306070639.7389-2-sergey.senozhatsky@gmail.com Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Huang Ying
|
cb9f753a37 |
mm: fix races between swapoff and flush dcache
Thanks to commit
|
|
|
Dan Williams
|
05ea88608d |
mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct
When device-dax is operating in huge-page mode we want it to behave like
hugetlbfs and report the MMU page mapping size that is being enforced by
the vma.
Similar to commit
|
|
|
Dan Williams
|
09135cc594 |
mm, powerpc: use vma_kernel_pagesize() in vma_mmu_pagesize()
Patch series "mm, smaps: MMUPageSize for device-dax", v3.
Similar to commit
|
|
|
Mario Leinweber
|
2923117b71 |
mm/gup.c: fix coding style issues.
- Fixed style error: 8 spaces -> 1 tab. - Fixed style warning: Corrected misleading indentation. Link: http://lkml.kernel.org/r/20180302210254.31888-1-marioleinweber@web.de Signed-off-by: Mario Leinweber <marioleinweber@web.de> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Aaron Lu
|
97334162e4 |
mm/free_pcppages_bulk: prefetch buddy while not holding lock
When a page is freed back to the global pool, its buddy will be checked
to see if it's possible to do a merge. This requires accessing buddy's
page structure and that access could take a long time if it's cache
cold.
This patch adds a prefetch to the to-be-freed page's buddy outside of
zone->lock in hope of accessing buddy's page structure later under
zone->lock will be faster. Since we *always* do buddy merging and check
an order-0 page's buddy to try to merge it when it goes into the main
allocator, the cacheline will always come in, i.e. the prefetched data
will never be unused.
Normally, the number of prefetch will be pcp->batch(default=31 and has
an upper limit of (PAGE_SHIFT * 8)=96 on x86_64) but in the case of
pcp's pages get all drained, it will be pcp->count which has an upper
limit of pcp->high. pcp->high, although has a default value of 186
(pcp->batch=31 * 6), can be changed by user through
/proc/sys/vm/percpu_pagelist_fraction and there is no software upper
limit so could be large, like several thousand. For this reason, only
the first pcp->batch number of page's buddy structure is prefetched to
avoid excessive prefetching.
In the meantime, there are two concerns:
1. the prefetch could potentially evict existing cachelines, especially
for L1D cache since it is not huge
2. there is some additional instruction overhead, namely calculating
buddy pfn twice
For 1, it's hard to say, this microbenchmark though shows good result
but the actual benefit of this patch will be workload/CPU dependant;
For 2, since the calculation is a XOR on two local variables, it's
expected in many cases that cycles spent will be offset by reduced
memory latency later. This is especially true for NUMA machines where
multiple CPUs are contending on zone->lock and the most time consuming
part under zone->lock is the wait of 'struct page' cacheline of the
to-be-freed pages and their buddies.
Test with will-it-scale/page_fault1 full load:
kernel Broadwell(2S) Skylake(2S) Broadwell(4S) Skylake(4S)
v4.16-rc2+ 9034215 7971818 13667135 15677465
patch2/3
|
|
|
Aaron Lu
|
0a5f4e5b45 |
mm/free_pcppages_bulk: do not hold lock when picking pages to free
When freeing a batch of pages from Per-CPU-Pages(PCP) back to buddy, the
zone->lock is held and then pages are chosen from PCP's migratetype
list. While there is actually no need to do this 'choose part' under
lock since it's PCP pages, the only CPU that can touch them is us and
irq is also disabled.
Moving this part outside could reduce lock held time and improve
performance. Test with will-it-scale/page_fault1 full load:
kernel Broadwell(2S) Skylake(2S) Broadwell(4S) Skylake(4S)
v4.16-rc2+ 9034215 7971818 13667135 15677465
this patch
|
|
|
Aaron Lu
|
77ba9062e4 |
mm/free_pcppages_bulk: update pcp->count inside
Matthew Wilcox found that all callers of free_pcppages_bulk() currently update pcp->count immediately after so it's natural to do it inside free_pcppages_bulk(). No functionality or performance change is expected from this patch. Link: http://lkml.kernel.org/r/20180301062845.26038-2-aaron.lu@intel.com Signed-off-by: Aaron Lu <aaron.lu@intel.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Huang Ying <ying.huang@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kemi Wang <kemi.wang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Rientjes
|
bc3106b26c |
mm, compaction: drain pcps for zone when kcompactd fails
It's possible for free pages to become stranded on per-cpu pagesets
(pcps) that, if drained, could be merged with buddy pages on the zone's
free area to form large order pages, including up to MAX_ORDER.
Consider a verbose example using the tools/vm/page-types tool at the
beginning of a ZONE_NORMAL ('B' indicates a buddy page and 'S' indicates
a slab page). Pages on pcps do not have any page flags set.
109954 1 _______S________________________________________________________
109955 2 __________B_____________________________________________________
109957 1 ________________________________________________________________
109958 1 __________B_____________________________________________________
109959 7 ________________________________________________________________
109960 1 __________B_____________________________________________________
109961 9 ________________________________________________________________
10996a 1 __________B_____________________________________________________
10996b 3 ________________________________________________________________
10996e 1 __________B_____________________________________________________
10996f 1 ________________________________________________________________
...
109f8c 1 __________B_____________________________________________________
109f8d 2 ________________________________________________________________
109f8f 2 __________B_____________________________________________________
109f91 f ________________________________________________________________
109fa0 1 __________B_____________________________________________________
109fa1 7 ________________________________________________________________
109fa8 1 __________B_____________________________________________________
109fa9 1 ________________________________________________________________
109faa 1 __________B_____________________________________________________
109fab 1 _______S________________________________________________________
The compaction migration scanner is attempting to defragment this memory
since it is at the beginning of the zone. It has done so quite well,
all movable pages have been migrated. From pfn [0x109955, 0x109fab),
there are only buddy pages and pages without flags set.
These pages may be stranded on pcps that could otherwise allow this
memory to be coalesced if freed back to the zone free area. It is
possible that some of these pages may not be on pcps and that something
has called alloc_pages() and used the memory directly, but we rely on
the absence of __GFP_MOVABLE in these cases to allocate from
MIGATE_UNMOVABLE pageblocks to try to keep these MIGRATE_MOVABLE
pageblocks as free as possible.
These buddy and pcp pages, spanning 1,621 pages, could be coalesced and
allow for three transparent hugepages to be dynamically allocated.
Running the numbers for all such spans on the system, it was found that
there were over 400 such spans of only buddy pages and pages without
flags set at the time this /proc/kpageflags sample was collected.
Without this support, there were _no_ order-9 or order-10 pages free.
When kcompactd fails to defragment memory such that a cc.order page can
be allocated, drain all pcps for the zone back to the buddy allocator so
this stranding cannot occur. Compaction for that order will
subsequently be deferred, which acts as a ratelimit on this drain.
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803010340100.88270@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Howard McLauchlan
|
4f6923fbb3 |
mm: make should_failslab always available for fault injection
should_failslab() is a convenient function to hook into for directed
error injection into kmalloc(). However, it is only available if a
config flag is set.
The following BCC script, for example, fails kmalloc() calls after a
btrfs umount:
from bcc import BPF
prog = r"""
BPF_HASH(flag);
#include <linux/mm.h>
int kprobe__btrfs_close_devices(void *ctx) {
u64 key = 1;
flag.update(&key, &key);
return 0;
}
int kprobe__should_failslab(struct pt_regs *ctx) {
u64 key = 1;
u64 *res;
res = flag.lookup(&key);
if (res != 0) {
bpf_override_return(ctx, -ENOMEM);
}
return 0;
}
"""
b = BPF(text=prog)
while 1:
b.kprobe_poll()
This patch refactors the should_failslab implementation so that the
function is always available for error injection, independent of flags.
This change would be similar in nature to commit f5490d3ec921 ("block:
Add should_fail_bio() for bpf error injection").
Link: http://lkml.kernel.org/r/20180222020320.6944-1-hmclauchlan@fb.com
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Dou Liyang
|
14298d3663 |
mm/page_poison.c: make early_page_poison_param() __init
The early_param() is only called during kernel initialization, So Linux marks the function of it with __init macro to save memory. But it forgot to mark the early_page_poison_param(). So, Make it __init as well. Link: http://lkml.kernel.org/r/20180117034757.27024-1-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Dou Liyang
|
1173194e1e |
mm/page_owner.c: make early_page_owner_param() __init
The early_param() is only called during kernel initialization, So Linux marks the functions of it with __init macro to save memory. But it forgot to mark the early_page_owner_param(). So, Make it __init as well. Link: http://lkml.kernel.org/r/20180117034736.26963-1-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Dou Liyang
|
8bd30c1090 |
mm/kmemleak.c: make kmemleak_boot_config() __init
The early_param() is only called during kernel initialization, So Linux marks the functions of it with __init macro to save memory. But it forgot to mark the kmemleak_boot_config(). So, Make it __init as well. Link: http://lkml.kernel.org/r/20180117034720.26897-1-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Minchan Kim
|
e9e9b7ecee |
mm: swap: unify cluster-based and vma-based swap readahead
This patch makes do_swap_page() not need to be aware of two different swap readahead algorithms. Just unify cluster-based and vma-based readahead function call. Link: http://lkml.kernel.org/r/1509520520-32367-3-git-send-email-minchan@kernel.org Link: http://lkml.kernel.org/r/20180220085249.151400-3-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Minchan Kim
|
eaf649ebc3 |
mm: swap: clean up swap readahead
When I see recent change of swap readahead, I am very unhappy about current code structure which diverges two swap readahead algorithm in do_swap_page. This patch is to clean it up. Main motivation is that fault handler doesn't need to be aware of readahead algorithms but just should call swapin_readahead. As first step, this patch cleans up a little bit but not perfect (I just separate for review easier) so next patch will make the goal complete. [minchan@kernel.org: do not check readahead flag with THP anon] Link: http://lkml.kernel.org/r/874lm83zho.fsf@yhuang-dev.intel.com Link: http://lkml.kernel.org/r/20180227232611.169883-1-minchan@kernel.org Link: http://lkml.kernel.org/r/1509520520-32367-2-git-send-email-minchan@kernel.org Link: http://lkml.kernel.org/r/20180220085249.151400-2-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Tetsuo Handa
|
e830c63a62 |
mm,vmscan: don't pretend forward progress upon shrinker_rwsem contention
Since we no longer use return value of shrink_slab() for normal reclaim, the comment is no longer true. If some do_shrink_slab() call takes unexpectedly long (root cause of stall is currently unknown) when register_shrinker()/unregister_shrinker() is pending, trying to drop caches via /proc/sys/vm/drop_caches could become infinite cond_resched() loop if many mem_cgroup are defined. For safety, let's not pretend forward progress. Link: http://lkml.kernel.org/r/201802202229.GGF26507.LVFtMSOOHFJOQF@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Chinner <dchinner@redhat.com> Cc: Glauber Costa <glommer@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Vitaly Wool
|
5c9bab592f |
z3fold: limit use of stale list for allocation
Currently if z3fold couldn't find an unbuddied page it would first try to pull a page off the stale list. The problem with this approach is that we can't 100% guarantee that the page is not processed by the workqueue thread at the same time unless we run cancel_work_sync() on it, which we can't do if we're in an atomic context. So let's just limit stale list usage to non-atomic contexts only. Link: http://lkml.kernel.org/r/47ab51e7-e9c1-d30e-ab17-f734dbc3abce@gmail.com Signed-off-by: Vitaly Vul <vitaly.vul@sony.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: <Oleksiy.Avramchenko@sony.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Konstantin Khlebnikov
|
605ca5ede7 |
mm/huge_memory.c: reorder operations in __split_huge_page_tail()
THP split makes non-atomic change of tail page flags. This is almost ok because tail pages are locked and isolated but this breaks recent changes in page locking: non-atomic operation could clear bit PG_waiters. As a result concurrent sequence get_page_unless_zero() -> lock_page() might block forever. Especially if this page was truncated later. Fix is trivial: clone flags before unfreezing page reference counter. This race exists since commit |
|
|
Huang Ying
|
e92bb4dd96 |
mm: fix races between address_space dereference and free in page_evicatable
When page_mapping() is called and the mapping is dereferenced in
page_evicatable() through shrink_active_list(), it is possible for the
inode to be truncated and the embedded address space to be freed at the
same time. This may lead to the following race.
CPU1 CPU2
truncate(inode) shrink_active_list()
... page_evictable(page)
truncate_inode_page(mapping, page);
delete_from_page_cache(page)
spin_lock_irqsave(&mapping->tree_lock, flags);
__delete_from_page_cache(page, NULL)
page_cache_tree_delete(..)
... mapping = page_mapping(page);
page->mapping = NULL;
...
spin_unlock_irqrestore(&mapping->tree_lock, flags);
page_cache_free_page(mapping, page)
put_page(page)
if (put_page_testzero(page)) -> false
- inode now has no pages and can be freed including embedded address_space
mapping_unevictable(mapping)
test_bit(AS_UNEVICTABLE, &mapping->flags);
- we've dereferenced mapping which is potentially already free.
Similar race exists between swap cache freeing and page_evicatable()
too.
The address_space in inode and swap cache will be freed after a RCU
grace period. So the races are fixed via enclosing the page_mapping()
and address_space usage in rcu_read_lock/unlock(). Some comments are
added in code to make it clear what is protected by the RCU read lock.
Link: http://lkml.kernel.org/r/20180212081227.1940-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Andy Shevchenko
|
5ad3509364 |
mm: reuse DEFINE_SHOW_ATTRIBUTE() macro
...instead of open coding file operations followed by custom ->open() callbacks per each attribute. [andriy.shevchenko@linux.intel.com: add tags, fix compilation issue] Link: http://lkml.kernel.org/r/20180217144253.58604-1-andriy.shevchenko@linux.intel.com Link: http://lkml.kernel.org/r/20180214154644.54505-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Cc: Dennis Zhou <dennisszhou@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Rientjes
|
7f16f91fdf |
mm, page_alloc: move mirrored_kernelcore to __meminitdata
mirrored_kernelcore can be in __meminitdata, so move it there. At the same time, fixup section specifiers to be after the name of the variable per checkpatch. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121623280.179479@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Rientjes
|
a5c6d65093 |
mm, page_alloc: extend kernelcore and movablecore for percent
Both kernelcore= and movablecore= can be used to define the amount of ZONE_NORMAL and ZONE_MOVABLE on a system, respectively. This requires the system memory capacity to be known when specifying the command line, however. This introduces the ability to define both kernelcore= and movablecore= as a percentage of total system memory. This is convenient for systems software that wants to define the amount of ZONE_MOVABLE, for example, as a proportion of a system's memory rather than a hardcoded byte value. To define the percentage, the final character of the parameter should be a '%'. mhocko: "why is anyone using these options nowadays?" rientjes: : : Fragmentation of non-__GFP_MOVABLE pages due to low on memory : situations can pollute most pageblocks on the system, as much as 1GB of : slab being fragmented over 128GB of memory, for example. When the : amount of kernel memory is well bounded for certain systems, it is : better to aggressively reclaim from existing MIGRATE_UNMOVABLE : pageblocks rather than eagerly fallback to others. : : We have additional patches that help with this fragmentation if you're : interested, specifically kcompactd compaction of MIGRATE_UNMOVABLE : pageblocks triggered by fallback of non-__GFP_MOVABLE allocations and : draining of pcp lists back to the zone free area to prevent stranding. [rientjes@google.com: updates] Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802131700160.71590@chino.kir.corp.google.com Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802121622470.179479@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Naoya Horiguchi
|
31286a8484 |
mm: hwpoison: disable memory error handling on 1GB hugepage
Recently the following BUG was reported:
Injecting memory failure for pfn 0x3c0000 at process virtual address 0x7fe300000000
Memory failure: 0x3c0000: recovery action for huge page: Recovered
BUG: unable to handle kernel paging request at ffff8dfcc0003000
IP: gup_pgd_range+0x1f0/0xc20
PGD 17ae72067 P4D 17ae72067 PUD 0
Oops: 0000 [#1] SMP PTI
...
CPU: 3 PID: 5467 Comm: hugetlb_1gb Not tainted 4.15.0-rc8-mm1-abc+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014
You can easily reproduce this by calling madvise(MADV_HWPOISON) twice on
a 1GB hugepage. This happens because get_user_pages_fast() is not aware
of a migration entry on pud that was created in the 1st madvise() event.
I think that conversion to pud-aligned migration entry is working, but
other MM code walking over page table isn't prepared for it. We need
some time and effort to make all this work properly, so this patch
avoids the reported bug by just disabling error handling for 1GB
hugepage.
[n-horiguchi@ah.jp.nec.com: v2]
Link: http://lkml.kernel.org/r/1517284444-18149-1-git-send-email-n-horiguchi@ah.jp.nec.com
Link: http://lkml.kernel.org/r/1517207283-15769-1-git-send-email-n-horiguchi@ah.jp.nec.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Pavel Tatashin
|
d0dc12e86b |
mm/memory_hotplug: optimize memory hotplug
During memory hotplugging we traverse struct pages three times: 1. memset(0) in sparse_add_one_section() 2. loop in __add_section() to set do: set_page_node(page, nid); and SetPageReserved(page); 3. loop in memmap_init_zone() to call __init_single_pfn() This patch removes the first two loops, and leaves only loop 3. All struct pages are initialized in one place, the same as it is done during boot. The benefits: - We improve memory hotplug performance because we are not evicting the cache several times and also reduce loop branching overhead. - Remove condition from hotpath in __init_single_pfn(), that was added in order to fix the problem that was reported by Bharata in the above email thread, thus also improve performance during normal boot. - Make memory hotplug more similar to the boot memory initialization path because we zero and initialize struct pages only in one function. - Simplifies memory hotplug struct page initialization code, and thus enables future improvements, such as multi-threading the initialization of struct pages in order to improve hotplug performance even further on larger machines. [pasha.tatashin@oracle.com: v5] Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
fc44f7f923 |
mm/memory_hotplug: don't read nid from struct page during hotplug
During memory hotplugging the probe routine will leave struct pages uninitialized, the same as it is currently done during boot. Therefore, we do not want to access the inside of struct pages before __init_single_page() is called during onlining. Because during hotplug we know that pages in one memory block belong to the same numa node, we can skip the checking. We should keep checking for the boot case. [pasha.tatashin@oracle.com: s/register_new_memory()/hotplug_memory_register()] Link: http://lkml.kernel.org/r/20180228030308.1116-6-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180215165920.8570-6-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
f165b378bb |
mm: uninitialized struct page poisoning sanity checking
During boot we poison struct page memory in order to ensure that no one is accessing this memory until the struct pages are initialized in __init_single_page(). This patch adds more scrutiny to this checking by making sure that flags do not equal the poison pattern when they are accessed. The pattern is all ones. Since node id is also stored in struct page, and may be accessed quite early, we add this enforcement into page_to_nid() function as well. Note, this is applicable only when NODE_NOT_IN_PAGE_FLAGS=n [pasha.tatashin@oracle.com: v4] Link: http://lkml.kernel.org/r/20180215165920.8570-4-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180213193159.14606-4-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
ba32558523 |
mm/memory_hotplug: enforce block size aligned range check
Patch series "optimize memory hotplug", v3.
This patchset:
- Improves hotplug performance by eliminating a number of struct page
traverses during memory hotplug.
- Fixes some issues with hotplugging, where boundaries were not
properly checked. And on x86 block size was not properly aligned with
end of memory
- Also, potentially improves boot performance by eliminating condition
from __init_single_page().
- Adds robustness by verifying that that struct pages are correctly
poisoned when flags are accessed.
The following experiments were performed on Xeon(R) CPU E7-8895 v3 @
2.60GHz with 1T RAM:
booting in qemu with 960G of memory, time to initialize struct pages:
no-kvm:
TRY1 TRY2
BEFORE: 39.433668 39.39705
AFTER: 36.903781 36.989329
with-kvm:
BEFORE: 10.977447 11.103164
AFTER: 10.929072 10.751885
Hotplug 896G memory:
no-kvm:
TRY1 TRY2
BEFORE: 848.740000 846.910000
AFTER: 783.070000 786.560000
with-kvm:
TRY1 TRY2
BEFORE: 34.410000 33.57
AFTER: 29.810000 29.580000
This patch (of 6):
Start qemu with the following arguments:
-m 64G,slots=2,maxmem=66G -object memory-backend-ram,id=mem1,size=2G
Which: boots machine with 64G, and adds a device mem1 with 2G which can
be hotplugged later.
Also make sure that config has the following turned on:
CONFIG_MEMORY_HOTPLUG
CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
CONFIG_ACPI_HOTPLUG_MEMORY
Using the qemu monitor hotplug the memory (make sure config has (qemu)
device_add pc-dimm,id=dimm1,memdev=mem1
The operation will fail with the following trace:
WARNING: CPU: 0 PID: 91 at drivers/base/memory.c:205
pages_correctly_reserved+0xe6/0x110
Modules linked in:
CPU: 0 PID: 91 Comm: systemd-udevd Not tainted 4.16.0-rc1_pt_master #29
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:pages_correctly_reserved+0xe6/0x110
Call Trace:
memory_subsys_online+0x44/0xa0
device_online+0x51/0x80
store_mem_state+0x5e/0xe0
kernfs_fop_write+0xfa/0x170
__vfs_write+0x2e/0x150
vfs_write+0xa8/0x1a0
SyS_write+0x4d/0xb0
do_syscall_64+0x5d/0x110
entry_SYSCALL_64_after_hwframe+0x21/0x86
---[ end trace 6203bc4f1a5d30e8 ]---
The problem is detected in: drivers/base/memory.c
static bool pages_correctly_reserved(unsigned long start_pfn)
205 if (WARN_ON_ONCE(!pfn_valid(pfn)))
This function loops through every section in the newly added memory
block and verifies that the first pfn is valid, meaning section exists,
has mapping (struct page array), and is online.
The block size on x86 is usually 128M, but when machine is booted with
more than 64G of memory, the block size is changed to 2G: $ cat
/sys/devices/system/memory/block_size_bytes 80000000
or
$ dmesg | grep "block size"
[ 0.086469] x86/mm: Memory block size: 2048MB
During memory hotplug, and hotremove we verify that the range is section
size aligned, but we actually must verify that it is block size aligned,
because that is the proper unit for hotplug operations. See:
Documentation/memory-hotplug.txt
So, when the start_pfn of newly added memory is not block size aligned,
we can get a memory block that has only part of it with properly
populated sections.
In our case the start_pfn starts from the last_pfn (end of physical
memory).
$ dmesg | grep last_pfn
[ 0.000000] e820: last_pfn = 0x1040000 max_arch_pfn = 0x400000000
0x1040000 == 65G, and so is not 2G aligned!
The fix is to enforce that memory that is hotplugged and hotremoved is
block size aligned.
With this fix, running the above sequence yield to the following result:
(qemu) device_add pc-dimm,id=dimm1,memdev=mem1
Block size [0x80000000] unaligned hotplug range: start 0x1040000000,
size 0x80000000
acpi PNP0C80:00: add_memory failed
acpi PNP0C80:00: acpi_memory_enable_device() error
acpi PNP0C80:00: Enumeration failure
Link: http://lkml.kernel.org/r/20180213193159.14606-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Yang Shi
|
f0849ac0b8 |
mm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one()
For PTE-mapped THP, the compound THP has not been split to normal 4K
pages yet, the whole THP is considered referenced if any one of sub page
is referenced.
When walking PTE-mapped THP by pvmw, all relevant PTEs will be checked
to retrieve referenced bit. But, the current code just returns the
result of the last PTE. If the last PTE has not referenced, the
referenced flag will be cleared.
Just set referenced when ptep{pmdp}_clear_young_notify() returns true.
Link: http://lkml.kernel.org/r/1518212451-87134-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Reported-by: Gang Deng <gavin.dg@linux.alibaba.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Pavel Tatashin
|
c9e97a1997 |
mm: initialize pages on demand during boot
Deferred page initialization allows the boot cpu to initialize a small subset of the system's pages early in boot, with other cpus doing the rest later on. It is, however, problematic to know how many pages the kernel needs during boot. Different modules and kernel parameters may change the requirement, so the boot cpu either initializes too many pages or runs out of memory. To fix that, initialize early pages on demand. This ensures the kernel does the minimum amount of work to initialize pages during boot and leaves the rest to be divided in the multithreaded initialization path (deferred_init_memmap). The on-demand code is permanently disabled using static branching once deferred pages are initialized. After the static branch is changed to false, the overhead is up-to two branch-always instructions if the zone watermark check fails or if rmqueue fails. Sergey Senozhatsky noticed that while deferred pages currently make sense only on NUMA machines (we start one thread per latency node), CONFIG_NUMA is not a requirement for CONFIG_DEFERRED_STRUCT_PAGE_INIT, so that is also must be addressed in the patch. [akpm@linux-foundation.org: fix typo in comment, make deferred_pages static] [pasha.tatashin@oracle.com: fix min() type mismatch warning] Link: http://lkml.kernel.org/r/20180212164543.26592-1-pasha.tatashin@oracle.com [pasha.tatashin@oracle.com: use zone_to_nid() in deferred_grow_zone()] Link: http://lkml.kernel.org/r/20180214163343.21234-2-pasha.tatashin@oracle.com [pasha.tatashin@oracle.com: might_sleep warning] Link: http://lkml.kernel.org/r/20180306192022.28289-1-pasha.tatashin@oracle.com [akpm@linux-foundation.org: s/spin_lock/spin_lock_irq/ in page_alloc_init_late()] [pasha.tatashin@oracle.com: v5] Link: http://lkml.kernel.org/r/20180309220807.24961-3-pasha.tatashin@oracle.com [akpm@linux-foundation.org: tweak comments] [pasha.tatashin@oracle.com: v6] Link: http://lkml.kernel.org/r/20180313182355.17669-3-pasha.tatashin@oracle.com [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20180209192216.20509-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Steven Sistare <steven.sistare@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Gioh Kim <gi-oh.kim@profitbricks.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Pavel Tatashin
|
3a2d7fa8a3 |
mm: disable interrupts while initializing deferred pages
Vlastimil Babka reported about a window issue during which when deferred pages are initialized, and the current version of on-demand initialization is finished, allocations may fail. While this is highly unlikely scenario, since this kind of allocation request must be large, and must come from interrupt handler, we still want to cover it. We solve this by initializing deferred pages with interrupts disabled, and holding node_size_lock spin lock while pages in the node are being initialized. The on-demand deferred page initialization that comes later will use the same lock, and thus synchronize with deferred_init_memmap(). It is unlikely for threads that initialize deferred pages to be interrupted. They run soon after smp_init(), but before modules are initialized, and long before user space programs. This is why there is no adverse effect of having these threads running with interrupts disabled. [pasha.tatashin@oracle.com: v6] Link: http://lkml.kernel.org/r/20180313182355.17669-2-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180309220807.24961-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Gioh Kim <gi-oh.kim@profitbricks.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Randy Dunlap
|
8e7a0c9100 |
mm/swap_slots.c: use conditional compilation
For mm/swap_slots.c, use the traditional Linux method of conditional compilation and linking instead of always compiling it by using #ifdef CONFIG_SWAP and #endif for the entire source file (excluding header files). Link: http://lkml.kernel.org/r/c2a47015-0b5a-d0d9-8bc7-9984c049df20@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Tim Chen <tim.c.chen@linux.intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Anshuman Khandual
|
310253514b |
mm/migrate: rename migration reason MR_CMA to MR_CONTIG_RANGE
alloc_contig_range() initiates compaction and eventual migration for the purpose of either CMA or HugeTLB allocations. At present, the reason code remains the same MR_CMA for either of these cases. Let's make it MR_CONTIG_RANGE which will appropriately reflect the reason code in both these cases. Link: http://lkml.kernel.org/r/20180202091518.18798-1-khandual@linux.vnet.ibm.com Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
David Woodhouse
|
57a7702b12 |
mm: always print RLIMIT_DATA warning
The documentation for ignore_rlimit_data says that it will print a warning at first misuse. Yet it doesn't seem to do that. Fix the code to print the warning even when we allow the process to continue. Link: http://lkml.kernel.org/r/1517935505-9321-1-git-send-email-dwmw@amazon.co.uk Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Pavel Emelyanov <xemul@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Colin Ian King
|
c01f0b54ef |
mm/ksm.c: make stable_node_dup() static
stable_node_dup() is local to the source and does not need to be in global scope, so make it static. Cleans up sparse warning: mm/ksm.c:1321:13: warning: symbol 'stable_node_dup' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20180206221005.12642-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Shakeel Butt
|
f9e13c0a5a |
slab, slub: skip unnecessary kasan_cache_shutdown()
The kasan quarantine is designed to delay freeing slab objects to catch
use-after-free. The quarantine can be large (several percent of machine
memory size). When kmem_caches are deleted related objects are flushed
from the quarantine but this requires scanning the entire quarantine
which can be very slow. We have seen the kernel busily working on this
while holding slab_mutex and badly affecting cache_reaper, slabinfo
readers and memcg kmem cache creations.
It can easily reproduced by following script:
yes . | head -1000000 | xargs stat > /dev/null
for i in `seq 1 10`; do
seq 500 | (cd /cg/memory && xargs mkdir)
seq 500 | xargs -I{} sh -c 'echo $BASHPID > \
/cg/memory/{}/tasks && exec stat .' > /dev/null
seq 500 | (cd /cg/memory && xargs rmdir)
done
The busy stack:
kasan_cache_shutdown
shutdown_cache
memcg_destroy_kmem_caches
mem_cgroup_css_free
css_free_rwork_fn
process_one_work
worker_thread
kthread
ret_from_fork
This patch is based on the observation that if the kmem_cache to be
destroyed is empty then there should not be any objects of this cache in
the quarantine.
Without the patch the script got stuck for couple of hours. With the
patch the script completed within a second.
Link: http://lkml.kernel.org/r/20180327230603.54721-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
|
Mikulas Patocka
|
1ba586de22 |
mm/slab_common.c: remove test if cache name is accessible
Since commit
|
|
|
Shakeel Butt
|
613a5eb567 |
slab, slub: remove size disparity on debug kernel
I have noticed on debug kernel with SLAB, the size of some non-root
slabs were larger than their corresponding root slabs.
e.g. for radix_tree_node:
$cat /proc/slabinfo | grep radix
name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> ...
radix_tree_node 15052 15075 4096 1 1 ...
$cat /cgroup/memory/temp/memory.kmem.slabinfo | grep radix
name <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> ...
radix_tree_node 1581 158 4120 1 2 ...
However for SLUB in debug kernel, the sizes were same. On further
inspection it is found that SLUB always use kmem_cache.object_size to
measure the kmem_cache.size while SLAB use the given kmem_cache.size.
In the debug kernel the slab's size can be larger than its object_size.
Thus in the creation of non-root slab, the SLAB uses the root's size as
base to calculate the non-root slab's size and thus non-root slab's size
can be larger than the root slab's size. For SLUB, the non-root slab's
size is measured based on the root's object_size and thus the size will
remain same for root and non-root slab.
This patch makes slab's object_size the default base to measure the
slab's size.
Link: http://lkml.kernel.org/r/20180313165428.58699-1-shakeelb@google.com
Fixes:
|
|
|
Alexey Dobriyan
|
302d55d51d |
slab: use 32-bit arithmetic in freelist_randomize()
SLAB doesn't support 4GB+ of objects per slab, therefore randomization doesn't need size_t. Link: http://lkml.kernel.org/r/20180305200730.15812-25-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
870b1fbb03 |
slub: make size_from_object() return unsigned int
Function returns size of the object without red zone which can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-24-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
19af27aff9 |
slub: make struct kmem_cache_order_objects::x unsigned int
struct kmem_cache_order_objects is for mixing order and number of objects, and orders aren't big enough to warrant 64-bit width. Propagate unsignedness down so that everything fits. !!! Patch assumes that "PAGE_SIZE << order" doesn't overflow. !!! Link: http://lkml.kernel.org/r/20180305200730.15812-23-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
284b50ddcf |
slub: make slab_index() return unsigned int
slab_index() returns index of an object within a slab which is at most u15 (or u16?). Iterators additionally guarantee that "p >= addr". Link: http://lkml.kernel.org/r/20180305200730.15812-22-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
7bbdb81ee3 |
slab: make usercopy region 32-bit
If kmem case sizes are 32-bit, then usecopy region should be too. Link: http://lkml.kernel.org/r/20180305200730.15812-21-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
be4a7988b3 |
kasan: make kasan_cache_create() work with 32-bit slab cache sizes
If SLAB doesn't support 4GB+ kmem caches (it never did), KASAN should not do it as well. Link: http://lkml.kernel.org/r/20180305200730.15812-20-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
0293d1fdd6 |
slab: make kmem_cache_flags accept 32-bit object size
Now that all sizes are properly typed, propagate "unsigned int" down the callgraph. Link: http://lkml.kernel.org/r/20180305200730.15812-19-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
44065b2e29 |
slub: make ->size unsigned int
Linux doesn't support negative length objects (including meta data). Link: http://lkml.kernel.org/r/20180305200730.15812-18-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
1b473f29d5 |
slub: make ->object_size unsigned int
Linux doesn't support negative length objects. Link: http://lkml.kernel.org/r/20180305200730.15812-17-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
e5d9998f3e |
slub: make ->cpu_partial unsigned int
/* * cpu_partial determined the maximum number of objects * kept in the per cpu partial lists of a processor. */ Can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-15-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
52ee6d74aa |
slub: make ->inuse unsigned int
->inuse is "the number of bytes in actual use by the object", can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-14-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
3a3791ec2e |
slub: make ->align unsigned int
Kmem cache alignment can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-13-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
d66e52d1e8 |
slub: make ->reserved unsigned int
->reserved is either 0 or sizeof(struct rcu_head), can't be negative. Link: http://lkml.kernel.org/r/20180305200730.15812-12-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
|
Alexey Dobriyan
|
eb7235eb84 |
slub: make ->remote_node_defrag_ratio unsigned int
->remote_node_defrag_ratio is in range 0..1000. This also adds a check and modifies the behavior to return an error code. Before this patch invalid values were ignored. Link: http://lkml.kernel.org/r/20180305200730.15812-9-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |