remap_file_pages calls mmap_region, which may merge the VMA with other
existing VMAs, and free "vma". This can lead to a use-after-free bug.
Avoid the bug by remembering vm_flags before calling mmap_region, and
not trying to dereference vma later.
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7225522bb4 ("mm: munlock: batch non-THP page isolation and
munlock+putback using pagevec" introduced __munlock_pagevec() to speed
up munlock by holding lru_lock over multiple isolated pages. Pages that
fail to be isolated are put_page()d immediately, also within the lock.
This can lead to deadlock when __munlock_pagevec() becomes the holder of
the last page pin and put_page() leads to __page_cache_release() which
also locks lru_lock. The deadlock has been observed by Sasha Levin
using trinity.
This patch avoids the deadlock by deferring put_page() operations until
lru_lock is released. Another pagevec (which is also used by later
phases of the function is reused to gather the pages for put_page()
operation.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit ff6a6da60b ("mm: accelerate munlock() treatment of THP
pages") munlock skips tail pages of a munlocked THP page. However, when
the head page already has PageMlocked unset, it will not skip the tail
pages.
Commit 7225522bb4 ("mm: munlock: batch non-THP page isolation and
munlock+putback using pagevec") has added a PageTransHuge() check which
contains VM_BUG_ON(PageTail(page)). Sasha Levin found this triggered
using trinity, on the first tail page of a THP page without PageMlocked
flag.
This patch fixes the issue by skipping tail pages also in the case when
PageMlocked flag is unset. There is still a possibility of race with
THP page split between clearing PageMlocked and determining how many
pages to skip. The race might result in former tail pages not being
skipped, which is however no longer a bug, as during the skip the
PageTail flags are cleared.
However this race also affects correctness of NR_MLOCK accounting, which
is to be fixed in a separate patch.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'v3.13-rc6' into for-3.14/core
Needed to bring blk-mq uptodate, since changes have been going in
since for-3.14/core was established.
Fixup merge issues related to the immutable biovec changes.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Conflicts:
block/blk-flush.c
fs/btrfs/check-integrity.c
fs/btrfs/extent_io.c
fs/btrfs/scrub.c
fs/logfs/dev_bdev.c
/sys/kernel/slab/:t-0000048 # cat cpu_slabs
231 N0=16 N1=215
/sys/kernel/slab/:t-0000048 # cat slabs
145 N0=36 N1=109
See, the number of slabs is smaller than that of cpu slabs.
The bug was introduced by commit 49e2258586
("slub: per cpu cache for partial pages").
We should use page->pages instead of page->pobjects when calculating
the number of cpu partial slabs. This also fixes the mapping of slabs
and nodes.
As there's no variable storing the number of total/active objects in
cpu partial slabs, and we don't have user interfaces requiring those
statistics, I just add WARN_ON for those cases.
Cc: <stable@vger.kernel.org> # 3.2+
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
The arbitrary restriction on page counts offered by the core
migrate_page_move_mapping() code results in rather suspicious looking
fiddling with page reference counts in the aio_migratepage() operation.
To fix this, make migrate_page_move_mapping() take an extra_count parameter
that allows aio to tell the code about its own reference count on the page
being migrated.
While cleaning up aio_migratepage(), make it validate that the old page
being passed in is actually what aio_migratepage() expects to prevent
misbehaviour in the case of races.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Commit 597d795a2a ('mm: do not allocate page->ptl dynamically, if
spinlock_t fits to long') restructures some allocators that are compiled
even if USE_SPLIT_PTLOCKS arn't used. It results in compilation
failure:
mm/memory.c:4282:6: error: 'struct page' has no member named 'ptl'
mm/memory.c:4288:12: error: 'struct page' has no member named 'ptl'
Add in the missing ifdef.
Fixes: 597d795a2a ('mm: do not allocate page->ptl dynamically, if spinlock_t fits to long')
Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In struct page we have enough space to fit long-size page->ptl there,
but we use dynamically-allocated page->ptl if size(spinlock_t) is larger
than sizeof(int).
It hurts 64-bit architectures with CONFIG_GENERIC_LOCKBREAK, where
sizeof(spinlock_t) == 8, but it easily fits into struct page.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 81c0a2bb51 ("mm: page_alloc: fair zone allocator policy") meant
to bring aging fairness among zones in system, but it was overzealous
and badly regressed basic workloads on NUMA systems.
Due to the way kswapd and page allocator interacts, we still want to
make sure that all zones in any given node are used equally for all
allocations to maximize memory utilization and prevent thrashing on the
highest zone in the node.
While the same principle applies to NUMA nodes - memory utilization is
obviously improved by spreading allocations throughout all nodes -
remote references can be costly and so many workloads prefer locality
over memory utilization. The original change assumed that
zone_reclaim_mode would be a good enough predictor for that, but it
turned out to be as indicative as a coin flip.
Revert the NUMA aspect of the fairness until we can find a proper way to
make it configurable and agree on a sane default.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: <stable@kernel.org> # 3.12
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 73f038b863. The NUMA behaviour of this patch is
less than ideal. An alternative approch is to interleave allocations
only within local zones which is implemented in the next patch.
Cc: stable@vger.kernel.org
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In __page_check_address(), if address's pud is not present,
huge_pte_offset() will return NULL, we should check the return value.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: qiuxishi <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Acked-by: 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>
After a successful hugetlb page migration by soft offline, the source
page will either be freed into hugepage_freelists or buddy(over-commit
page). If page is in buddy, page_hstate(page) will be NULL. It will
hit a NULL pointer dereference in dequeue_hwpoisoned_huge_page().
BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
IP: [<ffffffff81163761>] dequeue_hwpoisoned_huge_page+0x131/0x1d0
PGD c23762067 PUD c24be2067 PMD 0
Oops: 0000 [#1] SMP
So check PageHuge(page) after call migrate_pages() successfully.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Tested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
update_pageblock_skip() only fits to compaction which tries to isolate
by pageblock unit. If isolate_migratepages_range() is called by CMA, it
try to isolate regardless of pageblock unit and it don't reference
get_pageblock_skip() by ignore_skip_hint. We should also respect it on
update_pageblock_skip() to prevent from setting the wrong information.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: <stable@vger.kernel.org> [3.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
queue_pages_range() isolates hugetlbfs pages and putback_lru_pages()
can't handle these. We should change it to putback_movable_pages().
Naoya said that it is worth going into stable, because it can break
in-use hugepage list.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: <stable@vger.kernel.org> [3.12.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eliminate the following (rand)config warning by adding missing PROC_FS
dependency:
warning: (HWPOISON_INJECT && MEM_SOFT_DIRTY) selects PROC_PAGE_MONITOR which has unmet direct dependencies (PROC_FS && MMU)
Signed-off-by: Sima Baymani <sima.baymani@gmail.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen noted a regression in a microbenchmark that loops around
open() and close() on an 8-node NUMA machine and bisected it down to
commit 81c0a2bb51 ("mm: page_alloc: fair zone allocator policy").
That change forces the slab allocations of the file descriptor to spread
out to all 8 nodes, causing remote references in the page allocator and
slab.
The round-robin policy is only there to provide fairness among memory
allocations that are reclaimed involuntarily based on pressure in each
zone. It does not make sense to apply it to unreclaimable kernel
allocations that are freed manually, in this case instantly after the
allocation, and incur the remote reference costs twice for no reason.
Only round-robin allocations that are usually freed through page reclaim
or slab shrinking.
Bisected by Dave Hansen.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
THP migration can fail for a variety of reasons. Avoid flushing the TLB
to deal with THP migration races until the copy is ready to start.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.
The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.
During that time, a CPU may continue writing to the page.
This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.
When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.
This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).
The basic race looks like this:
CPU A CPU B CPU C
load TLB entry
make entry PTE/PMD_NUMA
fault on entry
read/write old page
start migrating page
change PTE/PMD to new page
read/write old page [*]
flush TLB
reload TLB from new entry
read/write new page
lose data
[*] the old page may belong to a new user at this point!
The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.
This should fix both NUMA migration and compaction.
[mgorman@suse.de: fix build]
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_huge_pmd_numa_page() handles the case where there is parallel THP
migration. However, by the time it is checked the NUMA hinting
information has already been disrupted. This patch adds an earlier
check with some helpers.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On a protection change it is no longer clear if the page should be still
accessible. This patch clears the NUMA hinting fault bits on a
protection change.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a PMD changes during a THP migration then migration aborts but the
failure path is doing more work than is necessary.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The anon_vma lock prevents parallel THP splits and any associated
complexity that arises when handling splits during THP migration. This
patch checks if the lock was successfully acquired and bails from THP
migration if it failed for any reason.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The TLB must be flushed if the PTE is updated but change_pte_range is
clearing the PTE while marking PTEs pte_numa without necessarily
flushing the TLB if it reinserts the same entry. Without the flush,
it's conceivable that two processors have different TLBs for the same
virtual address and at the very least it would generate spurious faults.
This patch only unmaps the pages in change_pte_range for a full
protection change.
[riel@redhat.com: write pte_numa pte back to the page tables]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Chegu Vinod <chegu_vinod@hp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the PMD is flushed then a parallel fault in handle_mm_fault() will
enter the pmd_none and do_huge_pmd_anonymous_page() path where it'll
attempt to insert a huge zero page. This is wasteful so the patch
avoids clearing the PMD when setting pmd_numa.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On x86, PMD entries are similar to _PAGE_PROTNONE protection and are
handled as NUMA hinting faults. The following two page table protection
bits are what defines them
_PAGE_NUMA:set _PAGE_PRESENT:clear
A PMD is considered present if any of the _PAGE_PRESENT, _PAGE_PROTNONE,
_PAGE_PSE or _PAGE_NUMA bits are set. If pmdp_invalidate encounters a
pmd_numa, it clears the present bit leaving _PAGE_NUMA which will be
considered not present by the CPU but present by pmd_present. The
existing caller of pmdp_invalidate should handle it but it's an
inconsistent state for a PMD. This patch keeps the state consistent
when calling pmdp_invalidate.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MMU notifiers must be called on THP page migration or secondary MMUs
will get very confused.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Base pages are unmapped and flushed from cache and TLB during normal
page migration and replaced with a migration entry that causes any
parallel NUMA hinting fault or gup to block until migration completes.
THP does not unmap pages due to a lack of support for migration entries
at a PMD level. This allows races with get_user_pages and
get_user_pages_fast which commit 3f926ab945 ("mm: Close races between
THP migration and PMD numa clearing") made worse by introducing a
pmd_clear_flush().
This patch forces get_user_page (fast and normal) on a pmd_numa page to
go through the slow get_user_page path where it will serialise against
THP migration and properly account for the NUMA hinting fault. On the
migration side the page table lock is taken for each PTE update.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4942642080 ("mm: memcg: handle non-error OOM situations more
gracefully") allowed tasks that already entered a memcg OOM condition to
bypass the memcg limit on subsequent allocation attempts hoping this
would expedite finishing the page fault and executing the kill.
David Rientjes is worried that this breaks memcg isolation guarantees
and since there is no evidence that the bypass actually speeds up fault
processing just change it so that these subsequent charge attempts fail
outright. The notable exception being __GFP_NOFAIL charges which are
required to bypass the limit regardless.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-bt: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a race condition between a memcg being torn down and a swapin
triggered from a different memcg of a page that was recorded to belong
to the exiting memcg on swapout (with CONFIG_MEMCG_SWAP extension). The
result is unreclaimable pages pointing to dead memcgs, which can lead to
anything from endless loops in later memcg teardown (the page is charged
to all hierarchical parents but is not on any LRU list) or crashes from
following the dangling memcg pointer.
Memcgs with tasks in them can not be torn down and usually charges don't
show up in memcgs without tasks. Swapin with the CONFIG_MEMCG_SWAP
extension is the notable exception because it charges the cgroup that
was recorded as owner during swapout, which may be empty and in the
process of being torn down when a task in another memcg triggers the
swapin:
teardown: swapin:
lookup_swap_cgroup_id()
rcu_read_lock()
mem_cgroup_lookup()
css_tryget()
rcu_read_unlock()
disable css_tryget()
call_rcu()
offline_css()
reparent_charges()
res_counter_charge() (hierarchical!)
css_put()
css_free()
pc->mem_cgroup = dead memcg
add page to dead lru
Add a final reparenting step into css_free() to make sure any such raced
charges are moved out of the memcg before it's finally freed.
In the longer term it would be cleaner to have the css_tryget() and the
res_counter charge under the same RCU lock section so that the charge
reparenting is deferred until the last charge whose tryget succeeded is
visible. But this will require more invasive changes that will be
harder to evaluate and backport into stable, so better defer them to a
separate change set.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Wagin reported crash on VM_BUG_ON() in pgtable_pmd_page_dtor() with
fallowing backtrace:
free_pgd_range+0x2bf/0x410
free_pgtables+0xce/0x120
unmap_region+0xe0/0x120
do_munmap+0x249/0x360
move_vma+0x144/0x270
SyS_mremap+0x3b9/0x510
system_call_fastpath+0x16/0x1b
The crash can be reproduce with this test case:
#define _GNU_SOURCE
#include <sys/mman.h>
#include <stdio.h>
#include <unistd.h>
#define MB (1024 * 1024UL)
#define GB (1024 * MB)
int main(int argc, char **argv)
{
char *p;
int i;
p = mmap((void *) GB, 10 * MB, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
for (i = 0; i < 10 * MB; i += 4096)
p[i] = 1;
mremap(p, 10 * MB, 10 * MB, MREMAP_FIXED | MREMAP_MAYMOVE, 2 * GB);
return 0;
}
Due to split PMD lock, we now store preallocated PTE tables for THP
pages per-PMD table. It means we need to move them to other PMD table
if huge PMD moved there.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Andrey Vagin <avagin@openvz.org>
Tested-by: Andrey Vagin <avagin@openvz.org>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 84235de394 ("fs: buffer: move allocation failure loop into the
allocator") started recognizing __GFP_NOFAIL in memory cgroups but
forgot to disable the OOM killer.
Any task that does not fail allocation will also not enter the OOM
completion path. So don't declare an OOM state in this case or it'll be
leaked and the task be able to bypass the limit until the next
userspace-triggered page fault cleans up the OOM state.
Reported-by: William Dauchy <wdauchy@gmail.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org> [3.12.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
change_prot_numa should work even if _PAGE_NUMA != _PAGE_PROTNONE.
On archs like ppc64 that don't use _PAGE_PROTNONE and also have
a separate page table outside linux pagetable, we just need to
make sure that when calling change_prot_numa we flush the
hardware page table entry so that next page access result in a numa
fault.
We still need to make sure we use the numa faulting logic only
when CONFIG_NUMA_BALANCING is set. This implies the migrate-on-fault
(Lazy migration) via mbind will only work if CONFIG_NUMA_BALANCING
is set.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs. This patch
replaces cftype->read_seq_string() with cftype->seq_show() which is
not limited to single_open() operation and will map directcly to
kernfs seq_file interface.
The conversions are mechanical. As ->seq_show() doesn't have @css and
@cft, the functions which make use of them are converted to use
seq_css() and seq_cft() respectively. In several occassions, e.f. if
it has seq_string in its name, the function name is updated to fit the
new method better.
This patch does not introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
All users of cftype->read() can be easily served, usually better, by
seq_file and other methods. Update hugetlb_cgroup_read() to return
u64 instead of printing itself and rename it to
hugetlb_cgroup_read_u64().
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
cftype->read_map() doesn't add any value and being replaced with
->read_seq_string(), and all users of cftype->read() can be easily
served, usually better, by seq_file and other methods.
Update mem_cgroup_read() to return u64 instead of printing itself and
rename it to mem_cgroup_read_u64(), and update
mem_cgroup_oom_control_read() to use ->read_seq_string() instead of
->read_map().
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
We have a problem where the big_key key storage implementation uses a
shmem backed inode to hold the key contents. Because of this detail of
implementation LSM checks are being done between processes trying to
read the keys and the tmpfs backed inode. The LSM checks are already
being handled on the key interface level and should not be enforced at
the inode level (since the inode is an implementation detail, not a
part of the security model)
This patch implements a new function shmem_kernel_file_setup() which
returns the equivalent to shmem_file_setup() only the underlying inode
has S_PRIVATE set. This means that all LSM checks for the inode in
question are skipped. It should only be used for kernel internal
operations where the inode is not exposed to userspace without proper
LSM checking. It is possible that some other users of
shmem_file_setup() should use the new interface, but this has not been
explored.
Reproducing this bug is a little bit difficult. The steps I used on
Fedora are:
(1) Turn off selinux enforcing:
setenforce 0
(2) Create a huge key
k=`dd if=/dev/zero bs=8192 count=1 | keyctl padd big_key test-key @s`
(3) Access the key in another context:
runcon system_u:system_r:httpd_t:s0-s0:c0.c1023 keyctl print $k >/dev/null
(4) Examine the audit logs:
ausearch -m AVC -i --subject httpd_t | audit2allow
If the last command's output includes a line that looks like:
allow httpd_t user_tmpfs_t:file { open read };
There was an inode check between httpd and the tmpfs filesystem. With
this patch no such denial will be seen. (NOTE! you should clear your
audit log if you have tested for this previously)
(Please return you box to enforcing)
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hugh Dickins <hughd@google.com>
cc: linux-mm@kvack.org
More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.
This updates callers for the new usage without changing the
implementation yet.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Jim Paris <jim@jtan.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: support@lsi.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand <geoff@infradead.org>
Merge v3.12 based patch series to move cgroup_event implementation to
memcg into for-3.14. The following two commits cause a conflict in
kernel/cgroup.c
2ff2a7d03b ("cgroup: kill css_id")
79bd9814e5 ("cgroup, memcg: move cgroup_event implementation to memcg")
Each patch removes a struct definition from kernel/cgroup.c. As the
two are adjacent, they cause a context conflict. Easily resolved by
removing both structs.
Signed-off-by: Tejun Heo <tj@kernel.org>
cgroup_event is only available in memcg now. Let's brand it that way.
While at it, add a comment encouraging deprecation of the feature and
remove the respective section from cgroup documentation.
This patch is cosmetic.
v3: Typo update as per Li Zefan.
v2: Index in cgroups.txt updated accordingly as suggested by Li Zefan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
cgroup_event is now memcg specific. Replace cgroup_event->css with
->memcg and convert [un]register_event() callbacks to take mem_cgroup
pointer instead of cgroup_subsys_state one. This simplifies the code
slightly and makes css_to_vmpressure() unnecessary which is removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
The only use of cgroup_event->cft is distinguishing "usage_in_bytes"
and "memsw.usgae_in_bytes" for mem_cgroup_usage_[un]register_event(),
which can be done by adding an explicit argument to the function and
implementing two wrappers so that the two cases can be distinguished
from the function alone.
Remove cgroup_event->cft and the related code including
[un]register_events() methods.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
cgroup_event is being moved from cgroup core to memcg and the
implementation is already moved by the previous patch. This patch
moves the data fields and callbacks.
* cgroup->event_list[_lock] are moved to mem_cgroup.
* cftype->[un]register_event() are moved to cgroup_event. This makes
it impossible for individual cftype definitions to specify their
event callbacks. This is worked around by simply hard-coding
filename to event callback mapping in cgroup_write_event_control().
This is awkward and inflexible, which is actually desirable given
that we don't want to grow more usages of this feature.
* eventfd_ctx declaration is removed from cgroup.h, which makes
vmpressure.h miss eventfd_ctx declaration. Include eventfd.h from
vmpressure.h.
v2: Use file name from dentry instead of cftype. This will allow
removing all cftype handling in the function.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
@css for cgroup_write_event_control() is now always for memcg and the
target file should be a memcg file too. Drop code which assumes @css
is dummy_css and the target file may belong to different subsystems.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
cgroup_event is way over-designed and tries to build a generic
flexible event mechanism into cgroup - fully customizable event
specification for each user of the interface. This is utterly
unnecessary and overboard especially in the light of the planned
unified hierarchy as there's gonna be single agent. Simply generating
events at fixed points, or if that's too restrictive, configureable
cadence or single set of configureable points should be enough.
Thankfully, memcg is the only user and gets to keep it. Replacing it
with something simpler on sane_behavior is strongly recommended.
This patch moves cgroup_event and "cgroup.event_control"
implementation to mm/memcontrol.c. Clearing of events on cgroup
destruction is moved from cgroup_destroy_locked() to
mem_cgroup_css_offline(), which shouldn't make any noticeable
difference.
cgroup_css() and __file_cft() are exported to enable the move;
however, this will soon be reverted once the event code is updated to
be memcg specific.
Note that "cgroup.event_control" will now exist only on the hierarchy
with memcg attached to it. While this change is visible to userland,
it is unlikely to be noticeable as the file has never been meaningful
outside memcg.
Aside from the above change, this is pure code relocation.
v2: Per Li Zefan's comments, init/Kconfig updated accordingly and
poll.h inclusion moved from cgroup.c to memcontrol.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Pull SLAB changes from Pekka Enberg:
"The patches from Joonsoo Kim switch mm/slab.c to use 'struct page' for
slab internals similar to mm/slub.c. This reduces memory usage and
improves performance:
https://lkml.org/lkml/2013/10/16/155
Rest of the changes are bug fixes from various people"
* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux: (21 commits)
mm, slub: fix the typo in mm/slub.c
mm, slub: fix the typo in include/linux/slub_def.h
slub: Handle NULL parameter in kmem_cache_flags
slab: replace non-existing 'struct freelist *' with 'void *'
slab: fix to calm down kmemleak warning
slub: proper kmemleak tracking if CONFIG_SLUB_DEBUG disabled
slab: rename slab_bufctl to slab_freelist
slab: remove useless statement for checking pfmemalloc
slab: use struct page for slab management
slab: replace free and inuse in struct slab with newly introduced active
slab: remove SLAB_LIMIT
slab: remove kmem_bufctl_t
slab: change the management method of free objects of the slab
slab: use __GFP_COMP flag for allocating slab pages
slab: use well-defined macro, virt_to_slab()
slab: overloading the RCU head over the LRU for RCU free
slab: remove cachep in struct slab_rcu
slab: remove nodeid in struct slab
slab: remove colouroff in struct slab
slab: change return type of kmem_getpages() to struct page
...
Fengguang Wu reports that compiling mm/mempolicy.c results in a warning:
mm/mempolicy.c: In function 'mpol_to_str':
mm/mempolicy.c:2878:2: error: format not a string literal and no format arguments
Kees says this is because he is using -Wformat-security.
Silence the warning.
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7cb2ef56e6 ("mm: fix aio performance regression for database
caused by THP") can cause dereference of a dangling pointer if
split_huge_page runs during PageHuge() if there are updates to the
tail_page->private field.
Also it is repeating compound_head twice for hugetlbfs and it is running
compound_head+compound_trans_head for THP when a single one is needed in
both cases.
The new code within the PageSlab() check doesn't need to verify that the
THP page size is never bigger than the smallest hugetlbfs page size, to
avoid memory corruption.
A longstanding theoretical race condition was found while fixing the
above (see the change right after the skip_unlock label, that is
relevant for the compound_lock path too).
By re-establishing the _mapcount tail refcounting for all compound
pages, this also fixes the below problem:
echo 0 >/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
BUG: Bad page state in process bash pfn:59a01
page:ffffea000139b038 count:0 mapcount:10 mapping: (null) index:0x0
page flags: 0x1c00000000008000(tail)
Modules linked in:
CPU: 6 PID: 2018 Comm: bash Not tainted 3.12.0+ #25
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
dump_stack+0x55/0x76
bad_page+0xd5/0x130
free_pages_prepare+0x213/0x280
__free_pages+0x36/0x80
update_and_free_page+0xc1/0xd0
free_pool_huge_page+0xc2/0xe0
set_max_huge_pages.part.58+0x14c/0x220
nr_hugepages_store_common.isra.60+0xd0/0xf0
nr_hugepages_store+0x13/0x20
kobj_attr_store+0xf/0x20
sysfs_write_file+0x189/0x1e0
vfs_write+0xc5/0x1f0
SyS_write+0x55/0xb0
system_call_fastpath+0x16/0x1b
Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now, the migration code in migrate_page_copy() uses copy_huge_page()
for hugetlbfs and thp pages:
if (PageHuge(page) || PageTransHuge(page))
copy_huge_page(newpage, page);
So, yay for code reuse. But:
void copy_huge_page(struct page *dst, struct page *src)
{
struct hstate *h = page_hstate(src);
and a non-hugetlbfs page has no page_hstate(). This works 99% of the
time because page_hstate() determines the hstate from the page order
alone. Since the page order of a THP page matches the default hugetlbfs
page order, it works.
But, if you change the default huge page size on the boot command-line
(say default_hugepagesz=1G), then we might not even *have* a 2MB hstate
so page_hstate() returns null and copy_huge_page() oopses pretty fast
since copy_huge_page() dereferences the hstate:
void copy_huge_page(struct page *dst, struct page *src)
{
struct hstate *h = page_hstate(src);
if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) {
...
Mel noticed that the migration code is really the only user of these
functions. This moves all the copy code over to migrate.c and makes
copy_huge_page() work for THP by checking for it explicitly.
I believe the bug was introduced in commit b32967ff10 ("mm: numa: Add
THP migration for the NUMA working set scanning fault case")
[akpm@linux-foundation.org: fix coding-style and comment text, per Naoya Horiguchi]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit ea1e7ed337.
Al points out that while the commit *does* actually create a separate
slab for the page->ptl allocation, that slab is never actually used, and
the code continues to use kmalloc/kfree.
Damien Wyart points out that the original patch did have the conversion
to use kmem_cache_alloc/free, so it got lost somewhere on its way to me.
Revert the half-arsed attempt that didn't do anything. If we really do
want the special slab (remember: this is all relevant just for debug
builds, so it's not necessarily all that critical) we might as well redo
the patch fully.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill A Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull trivial tree updates from Jiri Kosina:
"Usual earth-shaking, news-breaking, rocket science pile from
trivial.git"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
doc: add missing files to timers/00-INDEX
timekeeping: Fix some trivial typos in comments
mm: Fix some trivial typos in comments
irq: Fix some trivial typos in comments
NUMA: fix typos in Kconfig help text
mm: update 00-INDEX
doc: Documentation/DMA-attributes.txt fix typo
DRM: comment: `halve' -> `half'
Docs: Kconfig: `devlopers' -> `developers'
doc: typo on word accounting in kprobes.c in mutliple architectures
treewide: fix "usefull" typo
treewide: fix "distingush" typo
mm/Kconfig: Grammar s/an/a/
kexec: Typo s/the/then/
Documentation/kvm: Update cpuid documentation for steal time and pv eoi
treewide: Fix common typo in "identify"
__page_to_pfn: Fix typo in comment
Correct some typos for word frequency
clk: fixed-factor: Fix a trivial typo
...
This patch enhances the type safety for the kfifo API. It is now safe
to put const data into a non const FIFO and the API will now generate a
compiler warning when reading from the fifo where the destination
address is pointing to a const variable.
As a side effect the kfifo_put() does now expect the value of an element
instead a pointer to the element. This was suggested Russell King. It
make the handling of the kfifo_put easier since there is no need to
create a helper variable for getting the address of a pointer or to pass
integers of different sizes.
IMHO the API break is okay, since there are currently only six users of
kfifo_put().
The code is also cleaner by kicking out the "if (0)" expressions.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If DEBUG_SPINLOCK and DEBUG_LOCK_ALLOC are enabled spinlock_t on x86_64
is 72 bytes. For page->ptl they will be allocated from kmalloc-96 slab,
so we loose 24 on each. An average system can easily allocate few tens
thousands of page->ptl and overhead is significant.
Let's create a separate slab for page->ptl allocation to solve this.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use kernel/bounds.c to convert build-time spinlock_t size check into a
preprocessor symbol and apply that to properly separate the page::ptl
situation.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If split page table lock is in use, we embed the lock into struct page
of table's page. We have to disable split lock, if spinlock_t is too
big be to be embedded, like when DEBUG_SPINLOCK or DEBUG_LOCK_ALLOC
enabled.
This patch add support for dynamic allocation of split page table lock
if we can't embed it to struct page.
page->ptl is unsigned long now and we use it as spinlock_t if
sizeof(spinlock_t) <= sizeof(long), otherwise it's pointer to spinlock_t.
The spinlock_t allocated in pgtable_page_ctor() for PTE table and in
pgtable_pmd_page_ctor() for PMD table. All other helpers converted to
support dynamically allocated page->ptl.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The basic idea is the same as with PTE level: the lock is embedded into
struct page of table's page.
We can't use mm->pmd_huge_pte to store pgtables for THP, since we don't
take mm->page_table_lock anymore. Let's reuse page->lru of table's page
for that.
pgtable_pmd_page_ctor() returns true, if initialization is successful
and false otherwise. Current implementation never fails, but assumption
that constructor can fail will help to port it to -rt where spinlock_t
is rather huge and cannot be embedded into struct page -- dynamic
allocation is required.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Alex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently mm->pmd_huge_pte protected by page table lock. It will not
work with split lock. We have to have per-pmd pmd_huge_pte for proper
access serialization.
For now, let's just introduce wrapper to access mm->pmd_huge_pte.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Alex Thorlton <athorlton@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With split ptlock it's important to know which lock
pmd_trans_huge_lock() took. This patch adds one more parameter to the
function to return the lock.
In most places migration to new api is trivial. Exception is
move_huge_pmd(): we need to take two locks if pmd tables are different.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Alex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's only one caller of do_generic_file_read() and the only actor is
file_read_actor(). No reason to have a callback parameter.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull core locking changes from Ingo Molnar:
"The biggest changes:
- add lockdep support for seqcount/seqlocks structures, this
unearthed both bugs and required extra annotation.
- move the various kernel locking primitives to the new
kernel/locking/ directory"
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
block: Use u64_stats_init() to initialize seqcounts
locking/lockdep: Mark __lockdep_count_forward_deps() as static
lockdep/proc: Fix lock-time avg computation
locking/doc: Update references to kernel/mutex.c
ipv6: Fix possible ipv6 seqlock deadlock
cpuset: Fix potential deadlock w/ set_mems_allowed
seqcount: Add lockdep functionality to seqcount/seqlock structures
net: Explicitly initialize u64_stats_sync structures for lockdep
locking: Move the percpu-rwsem code to kernel/locking/
locking: Move the lglocks code to kernel/locking/
locking: Move the rwsem code to kernel/locking/
locking: Move the rtmutex code to kernel/locking/
locking: Move the semaphore core to kernel/locking/
locking: Move the spinlock code to kernel/locking/
locking: Move the lockdep code to kernel/locking/
locking: Move the mutex code to kernel/locking/
hung_task debugging: Add tracepoint to report the hang
x86/locking/kconfig: Update paravirt spinlock Kconfig description
lockstat: Report avg wait and hold times
lockdep, x86/alternatives: Drop ancient lockdep fixup message
...
Pull block IO core updates from Jens Axboe:
"This is the pull request for the core changes in the block layer for
3.13. It contains:
- The new blk-mq request interface.
This is a new and more scalable queueing model that marries the
best part of the request based interface we currently have (which
is fully featured, but scales poorly) and the bio based "interface"
which the new drivers for high IOPS devices end up using because
it's much faster than the request based one.
The bio interface has no block layer support, since it taps into
the stack much earlier. This means that drivers end up having to
implement a lot of functionality on their own, like tagging,
timeout handling, requeue, etc. The blk-mq interface provides all
these. Some drivers even provide a switch to select bio or rq and
has code to handle both, since things like merging only works in
the rq model and hence is faster for some workloads. This is a
huge mess. Conversion of these drivers nets us a substantial code
reduction. Initial results on converting SCSI to this model even
shows an 8x improvement on single queue devices. So while the
model was intended to work on the newer multiqueue devices, it has
substantial improvements for "classic" hardware as well. This code
has gone through extensive testing and development, it's now ready
to go. A pull request is coming to convert virtio-blk to this
model will be will be coming as well, with more drivers scheduled
for 3.14 conversion.
- Two blktrace fixes from Jan and Chen Gang.
- A plug merge fix from Alireza Haghdoost.
- Conversion of __get_cpu_var() from Christoph Lameter.
- Fix for sector_div() with 64-bit divider from Geert Uytterhoeven.
- A fix for a race between request completion and the timeout
handling from Jeff Moyer. This is what caused the merge conflict
with blk-mq/core, in case you are looking at that.
- A dm stacking fix from Mike Snitzer.
- A code consolidation fix and duplicated code removal from Kent
Overstreet.
- A handful of block bug fixes from Mikulas Patocka, fixing a loop
crash and memory corruption on blk cg.
- Elevator switch bug fix from Tomoki Sekiyama.
A heads-up that I had to rebase this branch. Initially the immutable
bio_vecs had been queued up for inclusion, but a week later, it became
clear that it wasn't fully cooked yet. So the decision was made to
pull this out and postpone it until 3.14. It was a straight forward
rebase, just pruning out the immutable series and the later fixes of
problems with it. The rest of the patches applied directly and no
further changes were made"
* 'for-3.13/core' of git://git.kernel.dk/linux-block: (31 commits)
block: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
block: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
block: Do not call sector_div() with a 64-bit divisor
kernel: trace: blktrace: remove redundent memcpy() in compat_blk_trace_setup()
block: Consolidate duplicated bio_trim() implementations
block: Use rw_copy_check_uvector()
block: Enable sysfs nomerge control for I/O requests in the plug list
block: properly stack underlying max_segment_size to DM device
elevator: acquire q->sysfs_lock in elevator_change()
elevator: Fix a race in elevator switching and md device initialization
block: Replace __get_cpu_var uses
bdi: test bdi_init failure
block: fix a probe argument to blk_register_region
loop: fix crash if blk_alloc_queue fails
blk-core: Fix memory corruption if blkcg_init_queue fails
block: fix race between request completion and timeout handling
blktrace: Send BLK_TN_PROCESS events to all running traces
blk-mq: don't disallow request merges for req->special being set
blk-mq: mq plug list breakage
blk-mq: fix for flush deadlock
...
Pull networking updates from David Miller:
1) The addition of nftables. No longer will we need protocol aware
firewall filtering modules, it can all live in userspace.
At the core of nftables is a, for lack of a better term, virtual
machine that executes byte codes to inspect packet or metadata
(arriving interface index, etc.) and make verdict decisions.
Besides support for loading packet contents and comparing them, the
interpreter supports lookups in various datastructures as
fundamental operations. For example sets are supports, and
therefore one could create a set of whitelist IP address entries
which have ACCEPT verdicts attached to them, and use the appropriate
byte codes to do such lookups.
Since the interpreted code is composed in userspace, userspace can
do things like optimize things before giving it to the kernel.
Another major improvement is the capability of atomically updating
portions of the ruleset. In the existing netfilter implementation,
one has to update the entire rule set in order to make a change and
this is very expensive.
Userspace tools exist to create nftables rules using existing
netfilter rule sets, but both kernel implementations will need to
co-exist for quite some time as we transition from the old to the
new stuff.
Kudos to Patrick McHardy, Pablo Neira Ayuso, and others who have
worked so hard on this.
2) Daniel Borkmann and Hannes Frederic Sowa made several improvements
to our pseudo-random number generator, mostly used for things like
UDP port randomization and netfitler, amongst other things.
In particular the taus88 generater is updated to taus113, and test
cases are added.
3) Support 64-bit rates in HTB and TBF schedulers, from Eric Dumazet
and Yang Yingliang.
4) Add support for new 577xx tigon3 chips to tg3 driver, from Nithin
Sujir.
5) Fix two fatal flaws in TCP dynamic right sizing, from Eric Dumazet,
Neal Cardwell, and Yuchung Cheng.
6) Allow IP_TOS and IP_TTL to be specified in sendmsg() ancillary
control message data, much like other socket option attributes.
From Francesco Fusco.
7) Allow applications to specify a cap on the rate computed
automatically by the kernel for pacing flows, via a new
SO_MAX_PACING_RATE socket option. From Eric Dumazet.
8) Make the initial autotuned send buffer sizing in TCP more closely
reflect actual needs, from Eric Dumazet.
9) Currently early socket demux only happens for TCP sockets, but we
can do it for connected UDP sockets too. Implementation from Shawn
Bohrer.
10) Refactor inet socket demux with the goal of improving hash demux
performance for listening sockets. With the main goals being able
to use RCU lookups on even request sockets, and eliminating the
listening lock contention. From Eric Dumazet.
11) The bonding layer has many demuxes in it's fast path, and an RCU
conversion was started back in 3.11, several changes here extend the
RCU usage to even more locations. From Ding Tianhong and Wang
Yufen, based upon suggestions by Nikolay Aleksandrov and Veaceslav
Falico.
12) Allow stackability of segmentation offloads to, in particular, allow
segmentation offloading over tunnels. From Eric Dumazet.
13) Significantly improve the handling of secret keys we input into the
various hash functions in the inet hashtables, TCP fast open, as
well as syncookies. From Hannes Frederic Sowa. The key fundamental
operation is "net_get_random_once()" which uses static keys.
Hannes even extended this to ipv4/ipv6 fragmentation handling and
our generic flow dissector.
14) The generic driver layer takes care now to set the driver data to
NULL on device removal, so it's no longer necessary for drivers to
explicitly set it to NULL any more. Many drivers have been cleaned
up in this way, from Jingoo Han.
15) Add a BPF based packet scheduler classifier, from Daniel Borkmann.
16) Improve CRC32 interfaces and generic SKB checksum iterators so that
SCTP's checksumming can more cleanly be handled. Also from Daniel
Borkmann.
17) Add a new PMTU discovery mode, IP_PMTUDISC_INTERFACE, which forces
using the interface MTU value. This helps avoid PMTU attacks,
particularly on DNS servers. From Hannes Frederic Sowa.
18) Use generic XPS for transmit queue steering rather than internal
(re-)implementation in virtio-net. From Jason Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits)
random32: add test cases for taus113 implementation
random32: upgrade taus88 generator to taus113 from errata paper
random32: move rnd_state to linux/random.h
random32: add prandom_reseed_late() and call when nonblocking pool becomes initialized
random32: add periodic reseeding
random32: fix off-by-one in seeding requirement
PHY: Add RTL8201CP phy_driver to realtek
xtsonic: add missing platform_set_drvdata() in xtsonic_probe()
macmace: add missing platform_set_drvdata() in mace_probe()
ethernet/arc/arc_emac: add missing platform_set_drvdata() in arc_emac_probe()
ipv6: protect for_each_sk_fl_rcu in mem_check with rcu_read_lock_bh
vlan: Implement vlan_dev_get_egress_qos_mask as an inline.
ixgbe: add warning when max_vfs is out of range.
igb: Update link modes display in ethtool
netfilter: push reasm skb through instead of original frag skbs
ip6_output: fragment outgoing reassembled skb properly
MAINTAINERS: mv643xx_eth: take over maintainership from Lennart
net_sched: tbf: support of 64bit rates
ixgbe: deleting dfwd stations out of order can cause null ptr deref
ixgbe: fix build err, num_rx_queues is only available with CONFIG_RPS
...
Merge first patch-bomb from Andrew Morton:
"Quite a lot of other stuff is banked up awaiting further
next->mainline merging, but this batch contains:
- Lots of random misc patches
- OCFS2
- Most of MM
- backlight updates
- lib/ updates
- printk updates
- checkpatch updates
- epoll tweaking
- rtc updates
- hfs
- hfsplus
- documentation
- procfs
- update gcov to gcc-4.7 format
- IPC"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (269 commits)
ipc, msg: fix message length check for negative values
ipc/util.c: remove unnecessary work pending test
devpts: plug the memory leak in kill_sb
./Makefile: export initial ramdisk compression config option
init/Kconfig: add option to disable kernel compression
drivers: w1: make w1_slave::flags long to avoid memory corruption
drivers/w1/masters/ds1wm.cuse dev_get_platdata()
drivers/memstick/core/ms_block.c: fix unreachable state in h_msb_read_page()
drivers/memstick/core/mspro_block.c: fix attributes array allocation
drivers/pps/clients/pps-gpio.c: remove redundant of_match_ptr
kernel/panic.c: reduce 1 byte usage for print tainted buffer
gcov: reuse kbasename helper
kernel/gcov/fs.c: use pr_warn()
kernel/module.c: use pr_foo()
gcov: compile specific gcov implementation based on gcc version
gcov: add support for gcc 4.7 gcov format
gcov: move gcov structs definitions to a gcc version specific file
kernel/taskstats.c: return -ENOMEM when alloc memory fails in add_del_listener()
kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end()
kernel/sysctl_binary.c: use scnprintf() instead of snprintf()
...
Pull vfs updates from Al Viro:
"All kinds of stuff this time around; some more notable parts:
- RCU'd vfsmounts handling
- new primitives for coredump handling
- files_lock is gone
- Bruce's delegations handling series
- exportfs fixes
plus misc stuff all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
ecryptfs: ->f_op is never NULL
locks: break delegations on any attribute modification
locks: break delegations on link
locks: break delegations on rename
locks: helper functions for delegation breaking
locks: break delegations on unlink
namei: minor vfs_unlink cleanup
locks: implement delegations
locks: introduce new FL_DELEG lock flag
vfs: take i_mutex on renamed file
vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
vfs: don't use PARENT/CHILD lock classes for non-directories
vfs: pull ext4's double-i_mutex-locking into common code
exportfs: fix quadratic behavior in filehandle lookup
exportfs: better variable name
exportfs: move most of reconnect_path to helper function
exportfs: eliminate unused "noprogress" counter
exportfs: stop retrying once we race with rename/remove
exportfs: clear DISCONNECTED on all parents sooner
exportfs: more detailed comment for path_reconnect
...
Pull cgroup changes from Tejun Heo:
"Not too much activity this time around. css_id is finally killed and
a minor update to device_cgroup"
* 'for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
device_cgroup: remove can_attach
cgroup: kill css_id
memcg: stop using css id
memcg: fail to create cgroup if the cgroup id is too big
memcg: convert to use cgroup id
memcg: convert to use cgroup_is_descendant()
Pull percpu changes from Tejun Heo:
"Two smallish changes for percpu. Two patches to remove unused
this_cpu_xor() and one to fix a bug in percpu init failure path so
that it can reach the proper BUG() instead of oopsing earlier"
* 'for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
x86: remove this_cpu_xor() implementation
percpu: remove this_cpu_xor() implementation
percpu: fix bootmem error handling in pcpu_page_first_chunk()
Commit 0255d49184 ("mm: Account for a THP NUMA hinting update as one
PTE update") was added to account for the number of PTE updates when
marking pages prot_numa. task_numa_work was using the old return value
to track how much address space had been updated. Altering the return
value causes the scanner to do more work than it is configured or
documented to in a single unit of work.
This patch reverts that commit and accounts for the number of THP
updates separately in vmstat. It is up to the administrator to
interpret the pair of values correctly. This is a straight-forward
operation and likely to only be of interest when actively debugging NUMA
balancing problems.
The impact of this patch is that the NUMA PTE scanner will scan slower
when THP is enabled and workloads may converge slower as a result. On
the flip size system CPU usage should be lower than recent tests
reported. This is an illustrative example of a short single JVM specjbb
test
specjbb
3.12.0 3.12.0
vanilla acctupdates
TPut 1 26143.00 ( 0.00%) 25747.00 ( -1.51%)
TPut 7 185257.00 ( 0.00%) 183202.00 ( -1.11%)
TPut 13 329760.00 ( 0.00%) 346577.00 ( 5.10%)
TPut 19 442502.00 ( 0.00%) 460146.00 ( 3.99%)
TPut 25 540634.00 ( 0.00%) 549053.00 ( 1.56%)
TPut 31 512098.00 ( 0.00%) 519611.00 ( 1.47%)
TPut 37 461276.00 ( 0.00%) 474973.00 ( 2.97%)
TPut 43 403089.00 ( 0.00%) 414172.00 ( 2.75%)
3.12.0 3.12.0
vanillaacctupdates
User 5169.64 5184.14
System 100.45 80.02
Elapsed 252.75 251.85
Performance is similar but note the reduction in system CPU time. While
this showed a performance gain, it will not be universal but at least
it'll be behaving as documented. The vmstats are obviously different but
here is an obvious interpretation of them from mmtests.
3.12.0 3.12.0
vanillaacctupdates
NUMA page range updates 1408326 11043064
NUMA huge PMD updates 0 21040
NUMA PTE updates 1408326 291624
"NUMA page range updates" == nr_pte_updates and is the value returned to
the NUMA pte scanner. NUMA huge PMD updates were the number of THP
updates which in combination can be used to calculate how many ptes were
updated from userspace.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Alex Thorlton <athorlton@sgi.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The same calculation is currently done in three differents places.
Factor that code so future changes has to be made at only one place.
[akpm@linux-foundation.org: uninline vm_commit_limit()]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The refcount routine was not fit the kernel get/put semantic exactly,
There were too many judgement statements on refcount and it could be
minus.
This patch does the following:
- move refcount judgement to zswap_entry_put() to hide resource free function.
- add a new function zswap_entry_find_get(), so that callers can use
easily in the following pattern:
zswap_entry_find_get
.../* do something */
zswap_entry_put
- to eliminate compile error, move some functions declaration
This patch is based on Minchan Kim <minchan@kernel.org> 's idea and suggestion.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Cc: Seth Jennings <sjennings@variantweb.net>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Consider the following scenario:
thread 0: reclaim entry x (get refcount, but not call zswap_get_swap_cache_page)
thread 1: call zswap_frontswap_invalidate_page to invalidate entry x.
finished, entry x and its zbud is not freed as its refcount != 0
now, the swap_map[x] = 0
thread 0: now call zswap_get_swap_cache_page
swapcache_prepare return -ENOENT because entry x is not used any more
zswap_get_swap_cache_page return ZSWAP_SWAPCACHE_NOMEM
zswap_writeback_entry do nothing except put refcount
Now, the memory of zswap_entry x and its zpage leak.
Modify:
- check the refcount in fail path, free memory if it is not referenced.
- use ZSWAP_SWAPCACHE_FAIL instead of ZSWAP_SWAPCACHE_NOMEM as the fail path
can be not only caused by nomem but also by invalidate.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Acked-by: Seth Jennings <sjenning@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>
We can't see the relationship with memcg from the parameters,
so the name with memcg_idx would be more reasonable.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Glauber Costa <glommer@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes the problem that get_unmapped_area() can return illegal
address and result in failing mmap(2) etc.
In case that the address higher than PAGE_SIZE is set to
/proc/sys/vm/mmap_min_addr, the address lower than mmap_min_addr can be
returned by get_unmapped_area(), even if you do not pass any virtual
address hint (i.e. the second argument).
This is because the current get_unmapped_area() code does not take into
account mmap_min_addr.
This leads to two actual problems as follows:
1. mmap(2) can fail with EPERM on the process without CAP_SYS_RAWIO,
although any illegal parameter is not passed.
2. The bottom-up search path after the top-down search might not work in
arch_get_unmapped_area_topdown().
Note: The first and third chunk of my patch, which changes "len" check,
are for more precise check using mmap_min_addr, and not for solving the
above problem.
[How to reproduce]
--- test.c -------------------------------------------------
#include <stdio.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/errno.h>
int main(int argc, char *argv[])
{
void *ret = NULL, *last_map;
size_t pagesize = sysconf(_SC_PAGESIZE);
do {
last_map = ret;
ret = mmap(0, pagesize, PROT_NONE,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
// printf("ret=%p\n", ret);
} while (ret != MAP_FAILED);
if (errno != ENOMEM) {
printf("ERR: unexpected errno: %d (last map=%p)\n",
errno, last_map);
}
return 0;
}
---------------------------------------------------------------
$ gcc -m32 -o test test.c
$ sudo sysctl -w vm.mmap_min_addr=65536
vm.mmap_min_addr = 65536
$ ./test (run as non-priviledge user)
ERR: unexpected errno: 1 (last map=0x10000)
Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When __rmqueue_fallback() doesn't find a free block with the required size
it splits a larger page and puts the rest of the page onto the free list.
But it has one serious mistake. When putting back, __rmqueue_fallback()
always use start_migratetype if type is not CMA. However,
__rmqueue_fallback() is only called when all of the start_migratetype
queue is empty. That said, __rmqueue_fallback always puts back memory to
the wrong queue except try_to_steal_freepages() changed pageblock type
(i.e. requested size is smaller than half of page block). The end result
is that the antifragmentation framework increases fragmenation instead of
decreasing it.
Mel's original anti fragmentation does the right thing. But commit
47118af076 ("mm: mmzone: MIGRATE_CMA migration type added") broke it.
This patch restores sane and old behavior. It also removes an incorrect
comment which was introduced by commit fef903efcf ("mm/page_alloc.c:
restructure free-page stealing code and fix a bug").
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In general, every tracepoint should be zero overhead if it is disabled.
However, trace_mm_page_alloc_extfrag() is one of exception. It evaluate
"new_type == start_migratetype" even if tracepoint is disabled.
However, the code can be moved into tracepoint's TP_fast_assign() and
TP_fast_assign exist exactly such purpose. This patch does it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, set_pageblock_migratetype() screws up MIGRATE_CMA and
MIGRATE_ISOLATE if page_group_by_mobility_disabled is true. It rewrites
the argument to MIGRATE_UNMOVABLE and we lost these attribute.
The problem was introduced by commit 49255c619f ("page allocator: move
check for disabled anti-fragmentation out of fastpath"). So a 4 year
old issue may mean that nobody uses page_group_by_mobility_disabled.
But anyway, this patch fixes the problem.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel's readahead algorithm sometimes interprets random read
accesses as sequential and triggers unnecessary data prefecthing from
storage device (impacting random read average latency).
In order to identify sequential cache read misses, the readahead
algorithm intends to check whether offset - previous offset == 1
(trivial sequential reads) or offset - previous offset == 0 (sequential
reads not aligned on page boundary):
if (offset - (ra->prev_pos >> PAGE_CACHE_SHIFT) <= 1UL)
The current offset is stored in the "offset" variable of type "pgoff_t"
(unsigned long), while previous offset is stored in "ra->prev_pos" of
type "loff_t" (long long). Therefore, operands of the if statement are
implicitly converted to type long long. Consequently, when previous
offset > current offset (which happens on random pattern), the if
condition is true and access is wrongly interpeted as sequential. An
unnecessary data prefetching is triggered, impacting the average random
read latency.
Storing the previous offset value in a "pgoff_t" variable (unsigned
long) fixes the sequential read detection logic.
Signed-off-by: Damien Ramonda <damien.ramonda@intel.com>
Reviewed-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Pierre Tardy <pierre.tardy@intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vmstat_cpuup_callback() is a CPU notifier callback, which marks N_CPU to a
node at CPU online event. However, it does not update this N_CPU info at
CPU offline event.
Changed vmstat_cpuup_callback() to clear N_CPU when the last CPU in the
node is put into offline, i.e. the node no longer has any online CPU.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After a system booted, N_CPU is not set to any node as has_cpu shows an
empty line.
# cat /sys/devices/system/node/has_cpu
(show-empty-line)
setup_vmstat() registers its CPU notifier callback,
vmstat_cpuup_callback(), which marks N_CPU to a node when a CPU is put
into online. However, setup_vmstat() is called after all CPUs are
launched in the boot sequence.
Changed setup_vmstat() to mark N_CPU to the nodes with online CPUs at
boot, which is consistent with other operations in
vmstat_cpuup_callback(), i.e. start_cpu_timer() and
refresh_zone_stat_thresholds().
Also added get_online_cpus() to protect the for_each_online_cpu() loop.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The hot-Pluggable field in SRAT specifies which memory is hotpluggable.
As we mentioned before, if hotpluggable memory is used by the kernel, it
cannot be hot-removed. So memory hotplug users may want to set all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it.
Memory hotplug users may also set a node as movable node, which has
ZONE_MOVABLE only, so that the whole node can be hot-removed.
But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the
kernel cannot use memory in movable nodes. This will cause NUMA
performance down. And other users may be unhappy.
So we need a way to allow users to enable and disable this functionality.
In this patch, we introduce movable_node boot option to allow users to
choose to not to consume hotpluggable memory at early boot time and later
we can set it as ZONE_MOVABLE.
To achieve this, the movable_node boot option will control the memblock
allocation direction. That said, after memblock is ready, before SRAT is
parsed, we should allocate memory near the kernel image as we explained in
the previous patches. So if movable_node boot option is set, the kernel
does the following:
1. After memblock is ready, make memblock allocate memory bottom up.
2. After SRAT is parsed, make memblock behave as default, allocate memory
top down.
Users can specify "movable_node" in kernel commandline to enable this
functionality. For those who don't use memory hotplug or who don't want
to lose their NUMA performance, just don't specify anything. The kernel
will work as before.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.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>
The Linux kernel cannot migrate pages used by the kernel. As a result,
kernel pages cannot be hot-removed. So we cannot allocate hotpluggable
memory for the kernel.
ACPI SRAT (System Resource Affinity Table) contains the memory hotplug
info. But before SRAT is parsed, memblock has already started to allocate
memory for the kernel. So we need to prevent memblock from doing this.
In a memory hotplug system, any numa node the kernel resides in should be
unhotpluggable. And for a modern server, each node could have at least
16GB memory. So memory around the kernel image is highly likely
unhotpluggable.
So the basic idea is: Allocate memory from the end of the kernel image and
to the higher memory. Since memory allocation before SRAT is parsed won't
be too much, it could highly likely be in the same node with kernel image.
The current memblock can only allocate memory top-down. So this patch
introduces a new bottom-up allocation mode to allocate memory bottom-up.
And later when we use this allocation direction to allocate memory, we
will limit the start address above the kernel.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Problem]
The current Linux cannot migrate pages used by the kernel because of the
kernel direct mapping. In Linux kernel space, va = pa + PAGE_OFFSET.
When the pa is changed, we cannot simply update the pagetable and keep the
va unmodified. So the kernel pages are not migratable.
There are also some other issues will cause the kernel pages not
migratable. For example, the physical address may be cached somewhere and
will be used. It is not to update all the caches.
When doing memory hotplug in Linux, we first migrate all the pages in one
memory device somewhere else, and then remove the device. But if pages
are used by the kernel, they are not migratable. As a result, memory used
by the kernel cannot be hot-removed.
Modifying the kernel direct mapping mechanism is too difficult to do. And
it may cause the kernel performance down and unstable. So we use the
following way to do memory hotplug.
[What we are doing]
In Linux, memory in one numa node is divided into several zones. One of
the zones is ZONE_MOVABLE, which the kernel won't use.
In order to implement memory hotplug in Linux, we are going to arrange all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use these
memory. To do this, we need ACPI's help.
In ACPI, SRAT(System Resource Affinity Table) contains NUMA info. The
memory affinities in SRAT record every memory range in the system, and
also, flags specifying if the memory range is hotpluggable. (Please refer
to ACPI spec 5.0 5.2.16)
With the help of SRAT, we have to do the following two things to achieve our
goal:
1. When doing memory hot-add, allow the users arranging hotpluggable as
ZONE_MOVABLE.
(This has been done by the MOVABLE_NODE functionality in Linux.)
2. when the system is booting, prevent bootmem allocator from allocating
hotpluggable memory for the kernel before the memory initialization
finishes.
The problem 2 is the key problem we are going to solve. But before solving it,
we need some preparation. Please see below.
[Preparation]
Bootloader has to load the kernel image into memory. And this memory must
be unhotpluggable. We cannot prevent this anyway. So in a memory hotplug
system, we can assume any node the kernel resides in is not hotpluggable.
Before SRAT is parsed, we don't know which memory ranges are hotpluggable.
But memblock has already started to work. In the current kernel,
memblock allocates the following memory before SRAT is parsed:
setup_arch()
|->memblock_x86_fill() /* memblock is ready */
|......
|->early_reserve_e820_mpc_new() /* allocate memory under 1MB */
|->reserve_real_mode() /* allocate memory under 1MB */
|->init_mem_mapping() /* allocate page tables, about 2MB to map 1GB memory */
|->dma_contiguous_reserve() /* specified by user, should be low */
|->setup_log_buf() /* specified by user, several mega bytes */
|->relocate_initrd() /* could be large, but will be freed after boot, should reorder */
|->acpi_initrd_override() /* several mega bytes */
|->reserve_crashkernel() /* could be large, should reorder */
|......
|->initmem_init() /* Parse SRAT */
According to Tejun's advice, before SRAT is parsed, we should try our best
to allocate memory near the kernel image. Since the whole node the kernel
resides in won't be hotpluggable, and for a modern server, a node may have
at least 16GB memory, allocating several mega bytes memory around the
kernel image won't cross to hotpluggable memory.
[About this patchset]
So this patchset is the preparation for the problem 2 that we want to
solve. It does the following:
1. Make memblock be able to allocate memory bottom up.
1) Keep all the memblock APIs' prototype unmodified.
2) When the direction is bottom up, keep the start address greater than the
end of kernel image.
2. Improve init_mem_mapping() to support allocate page tables in
bottom up direction.
3. Introduce "movable_node" boot option to enable and disable this
functionality.
This patch (of 6):
Create a new function __memblock_find_range_top_down to factor out of
top-down allocation from memblock_find_in_range_node. This is a
preparation because we will introduce a new bottom-up allocation mode in
the following patch.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is more or less the generic variant of commit 41aacc1eea ("x86
get_unmapped_area: Access mmap_legacy_base through mm_struct member").
So effectively architectures which use an own arch_pick_mmap_layout()
implementation but call the generic arch_get_unmapped_area() now can
also randomize their mmap_base.
All architectures which have an own arch_pick_mmap_layout() and call the
generic arch_get_unmapped_area() (arm64, s390, tile) currently set
mmap_base to TASK_UNMAPPED_BASE. This is also true for the generic
arch_pick_mmap_layout() function. So this change is a no-op currently.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Radu Caragea <sinaelgl@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add SetPageReclaim() before __swap_writepage() so that page can be moved
to the tail of the inactive list, which can avoid unnecessary page
scanning as this page was reclaimed by swap subsystem before.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During swapoff the frontswap_map was NULL-ified before calling
frontswap_invalidate_area(). However the frontswap_invalidate_area()
exits early if frontswap_map is NULL. Invalidate was never called
during swapoff.
This patch moves frontswap_map_set() in swapoff just after calling
frontswap_invalidate_area() so outside of locks (swap_lock and
swap_info_struct->lock). This shouldn't be a problem as during swapon
the frontswap_map_set() is called also outside of any locks.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 248ac0e194 ("mm/vmalloc: remove guard page from between vmap
blocks") had the side effect of making vmap_area.va_end member point to
the next vmap_area.va_start. This was creating an artificial reference
to vmalloc'ed objects and kmemleak was rarely reporting vmalloc() leaks.
This patch marks the vmap_area containing pointers explicitly and
reduces the min ref_count to 2 as vm_struct still contains a reference
to the vmalloc'ed object. The kmemleak add_scan_area() function has
been improved to allow a SIZE_MAX argument covering the rest of the
object (for simpler calling sites).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We pass the number of pages which hold page structs of a memory section
to free_map_bootmem(). This is right when !CONFIG_SPARSEMEM_VMEMMAP but
wrong when CONFIG_SPARSEMEM_VMEMMAP. When CONFIG_SPARSEMEM_VMEMMAP, we
should pass the number of pages of a memory section to free_map_bootmem.
So the fix is removing the nr_pages parameter. When
CONFIG_SPARSEMEM_VMEMMAP, we directly use the prefined marco
PAGES_PER_SECTION in free_map_bootmem. When !CONFIG_SPARSEMEM_VMEMMAP,
we calculate page numbers needed to hold the page structs for a memory
section and use the value in free_map_bootmem().
This was found by reading the code. And I have no machine that support
memory hot-remove to test the bug now.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For below functions,
- sparse_add_one_section()
- kmalloc_section_memmap()
- __kmalloc_section_memmap()
- __kfree_section_memmap()
they are always invoked to operate on one memory section, so it is
redundant to always pass a nr_pages parameter, which is the page numbers
in one section. So we can directly use predefined macro PAGES_PER_SECTION
instead of passing the parameter.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The memory.numa_stat file was not hierarchical. Memory charged to the
children was not shown in parent's numa_stat.
This change adds the "hierarchical_" stats to the existing stats. The
new hierarchical stats include the sum of all children's values in
addition to the value of the memcg.
Tested: Create cgroup a, a/b and run workload under b. The values of
b are included in the "hierarchical_*" under a.
$ cd /sys/fs/cgroup
$ echo 1 > memory.use_hierarchy
$ mkdir a a/b
Run workload in a/b:
$ (echo $BASHPID >> a/b/cgroup.procs && cat /some/file && bash) &
The hierarchical_ fields in parent (a) show use of workload in a/b:
$ cat a/memory.numa_stat
total=0 N0=0 N1=0 N2=0 N3=0
file=0 N0=0 N1=0 N2=0 N3=0
anon=0 N0=0 N1=0 N2=0 N3=0
unevictable=0 N0=0 N1=0 N2=0 N3=0
hierarchical_total=908 N0=552 N1=317 N2=39 N3=0
hierarchical_file=850 N0=549 N1=301 N2=0 N3=0
hierarchical_anon=58 N0=3 N1=16 N2=39 N3=0
hierarchical_unevictable=0 N0=0 N1=0 N2=0 N3=0
$ cat a/b/memory.numa_stat
total=908 N0=552 N1=317 N2=39 N3=0
file=850 N0=549 N1=301 N2=0 N3=0
anon=58 N0=3 N1=16 N2=39 N3=0
unevictable=0 N0=0 N1=0 N2=0 N3=0
hierarchical_total=908 N0=552 N1=317 N2=39 N3=0
hierarchical_file=850 N0=549 N1=301 N2=0 N3=0
hierarchical_anon=58 N0=3 N1=16 N2=39 N3=0
hierarchical_unevictable=0 N0=0 N1=0 N2=0 N3=0
Signed-off-by: Ying Han <yinghan@google.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Refactor mem_control_numa_stat_show() to use a new stats structure for
smaller and simpler code. This consolidates nearly identical code.
text data bss dec hex filename
8,137,679 1,703,496 1,896,448 11,737,623 b31a17 vmlinux.before
8,136,911 1,703,496 1,896,448 11,736,855 b31717 vmlinux.after
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Ying Han <yinghan@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Khugepaged will scan/free HPAGE_PMD_NR normal pages and replace with a
hugepage which is allocated from the node of the first scanned normal
page, but this policy is too rough and may end with unexpected result to
upper users.
The problem is the original page-balancing among all nodes will be
broken after hugepaged started. Thinking about the case if the first
scanned normal page is allocated from node A, most of other scanned
normal pages are allocated from node B or C.. But hugepaged will always
allocate hugepage from node A which will cause extra memory pressure on
node A which is not the situation before khugepaged started.
This patch try to fix this problem by making khugepaged allocate
hugepage from the node which have max record of scaned normal pages hit,
so that the effect to original page-balancing can be minimized.
The other problem is if normal scanned pages are equally allocated from
Node A,B and C, after khugepaged started Node A will still suffer extra
memory pressure.
Andrew Davidoff reported a related issue several days ago. He wanted
his application interleaving among all nodes and "numactl
--interleave=all ./test" was used to run the testcase, but the result
wasn't not as expected.
cat /proc/2814/numa_maps:
7f50bd440000 interleave:0-3 anon=51403 dirty=51403 N0=435 N1=435 N2=435 N3=50098
The end result showed that most pages are from Node3 instead of
interleave among node0-3 which was unreasonable.
This patch also fix this issue by allocating hugepage round robin from
all nodes have the same record, after this patch the result was as
expected:
7f78399c0000 interleave:0-3 anon=51403 dirty=51403 N0=12723 N1=12723 N2=13235 N3=12722
The simple testcase is like this:
int main() {
char *p;
int i;
int j;
for (i=0; i < 200; i++) {
p = (char *)malloc(1048576);
printf("malloc done\n");
if (p == 0) {
printf("Out of memory\n");
return 1;
}
for (j=0; j < 1048576; j++) {
p[j] = 'A';
}
printf("touched memory\n");
sleep(1);
}
printf("enter sleep\n");
while(1) {
sleep(100);
}
}
[akpm@linux-foundation.org: make last_khugepaged_target_node local to khugepaged_find_target_node()]
Reported-by: Andrew Davidoff <davidoff@qedmf.net>
Tested-by: Andrew Davidoff <davidoff@qedmf.net>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move alloc_hugepage() to a better place, no need for a seperate #ifndef
CONFIG_NUMA
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Davidoff <davidoff@qedmf.net>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The VM_UNINITIALIZED/VM_UNLIST flag introduced by f5252e009d ("mm:
avoid null pointer access in vm_struct via /proc/vmallocinfo") is used
to avoid accessing the pages field with unallocated page when
show_numa_info() is called.
This patch moves the check just before show_numa_info in order that some
messages still can be dumped via /proc/vmallocinfo. This patch reverts
commit d157a55815 ("mm/vmalloc.c: check VM_UNINITIALIZED flag in
s_show instead of show_numa_info");
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a race window between vmap_area tear down and show vmap_area
information.
A B
remove_vm_area
spin_lock(&vmap_area_lock);
va->vm = NULL;
va->flags &= ~VM_VM_AREA;
spin_unlock(&vmap_area_lock);
spin_lock(&vmap_area_lock);
if (va->flags & (VM_LAZY_FREE | VM_LAZY_FREEZING))
return 0;
if (!(va->flags & VM_VM_AREA)) {
seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
(void *)va->va_start, (void *)va->va_end,
va->va_end - va->va_start);
return 0;
}
free_unmap_vmap_area(va);
flush_cache_vunmap
free_unmap_vmap_area_noflush
unmap_vmap_area
free_vmap_area_noflush
va->flags |= VM_LAZY_FREE
The assumption !VM_VM_AREA represents vm_map_ram allocation is
introduced by d4033afdf8 ("mm, vmalloc: iterate vmap_area_list,
instead of vmlist, in vmallocinfo()").
However, !VM_VM_AREA also represents vmap_area is being tear down in
race window mentioned above. This patch fix it by don't dump any
information for !VM_VM_AREA case and also remove (VM_LAZY_FREE |
VM_LAZY_FREEING) check since they are not possible for !VM_VM_AREA case.
Suggested-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The caller address has already been set in set_vmalloc_vm(), there's no
need to set it again in __vmalloc_area_node.
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mpol_to_str() should not fail. Currently, it either fails because the
string buffer is too small or because a string hasn't been defined for a
mempolicy mode.
If a new mempolicy mode is introduced and no string is defined for it,
just warn and return "unknown".
If the buffer is too small, just truncate the string and return, the
same behavior as snprintf().
This also fixes a bug where there was no NULL-byte termination when doing
*p++ = '=' and *p++ ':' and maxlen has been reached.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Chen Gang <gang.chen@asianux.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chen Gong pointed out that set/unset_migratetype_isolate() was done in
different functions in mm/memory-failure.c, which makes the code less
readable/maintainable. So this patch does it in soft_offline_page().
With this patch, we get to hold lock_memory_hotplug() longer but it's
not a problem because races between memory hotplug and soft offline are
very rare.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Chen, Gong <gong.chen@linux.intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cpu_up() has #ifdef CONFIG_MEMORY_HOTPLUG code blocks, which call
mem_online_node() to put its node online if offlined and then call
build_all_zonelists() to initialize the zone list.
These steps are specific to memory hotplug, and should be managed in
mm/memory_hotplug.c. lock_memory_hotplug() should also be held for the
whole steps.
For this reason, this patch replaces mem_online_node() with
try_online_node(), which performs the whole steps with
lock_memory_hotplug() held. try_online_node() is named after
try_offline_node() as they have similar purpose.
There is no functional change in this patch.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On large memory machines it can take a few minutes to get through
free_all_bootmem().
Currently, when free_all_bootmem() calls __free_pages_memory(), the number
of contiguous pages that __free_pages_memory() passes to the buddy
allocator is limited to BITS_PER_LONG. BITS_PER_LONG was originally
chosen to keep things similar to mm/nobootmem.c. But it is more efficient
to limit it to MAX_ORDER.
base new change
8TB 202s 172s 30s
16TB 401s 351s 50s
That is around 1%-3% improvement on total boot time.
This patch was spun off from the boot time rfc Robin and I had been
working on.
Signed-off-by: Robin Holt <robin.m.holt@gmail.com>
Signed-off-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Robin Holt <robinmholt@linux.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use helper function to check if we need to deal with oom condition.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A is_memblock_offlined() return or 1 means memory block is offlined, but
is_memblock_offlined_cb() returning 1 means memory block is not offlined,
this will confuse somebody, so rename the function.
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use "if (zone->present_pages)" instead of "if (zone->present_pages)".
Simplify the code, no functional change.
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use "pgdat_end_pfn()" instead of "pgdat->node_start_pfn +
pgdat->node_spanned_pages". Simplify the code, no functional change.
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 13ece886d9 ("thp: transparent hugepage config choice"),
transparent hugepage support is disabled by default, and
TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
And since commit d39d33c332 ("thp: enable direct defrag"), defrag is
enable for all transparent hugepage page faults by default, not only in
MADV_HUGEPAGE regions.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: 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>
The callers of free_pgd_range() and hugetlb_free_pgd_range() don't hold
page table locks. The comments seems to be obsolete, so let's remove
them.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit f40d1e42bb ("mm: compaction: acquire the zone->lock as
late as possible"), isolate_freepages_block() takes the zone->lock
itself. The function description however still states that the
zone->lock must be held.
This patch removes this outdated statement.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kcalloc returns zeroed memory. There's no need to use this flag.
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The callee force_page_cache_readahead() already does this and unlike
do_readahead(), force_page_cache_readahead() remembers to check for
->readpages() as well.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull scheduler changes from Ingo Molnar:
"The main changes in this cycle are:
- (much) improved CONFIG_NUMA_BALANCING support from Mel Gorman, Rik
van Riel, Peter Zijlstra et al. Yay!
- optimize preemption counter handling: merge the NEED_RESCHED flag
into the preempt_count variable, by Peter Zijlstra.
- wait.h fixes and code reorganization from Peter Zijlstra
- cfs_bandwidth fixes from Ben Segall
- SMP load-balancer cleanups from Peter Zijstra
- idle balancer improvements from Jason Low
- other fixes and cleanups"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHED
stop_machine: Fix race between stop_two_cpus() and stop_cpus()
sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus
sched: Fix asymmetric scheduling for POWER7
sched: Move completion code from core.c to completion.c
sched: Move wait code from core.c to wait.c
sched: Move wait.c into kernel/sched/
sched/wait: Fix __wait_event_interruptible_lock_irq_timeout()
sched: Avoid throttle_cfs_rq() racing with period_timer stopping
sched: Guarantee new group-entities always have weight
sched: Fix hrtimer_cancel()/rq->lock deadlock
sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining
sched: Fix race on toggling cfs_bandwidth_used
sched: Remove extra put_online_cpus() inside sched_setaffinity()
sched/rt: Fix task_tick_rt() comment
sched/wait: Fix build breakage
sched/wait: Introduce prepare_to_wait_event()
sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too
sched: Remove get_online_cpus() usage
sched: Fix race in migrate_swap_stop()
...
There were two places where return value from bdi_init was not tested.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently seqlocks and seqcounts don't support lockdep.
After running across a seqcount related deadlock in the timekeeping
code, I used a less-refined and more focused variant of this patch
to narrow down the cause of the issue.
This is a first-pass attempt to properly enable lockdep functionality
on seqlocks and seqcounts.
Since seqcounts are used in the vdso gettimeofday code, I've provided
non-lockdep accessors for those needs.
I've also handled one case where there were nested seqlock writers
and there may be more edge cases.
Comments and feedback would be appreciated!
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Conflicts:
kernel/Makefile
There are conflicts in kernel/Makefile due to file moving in the
scheduler tree - resolve them.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Conflicts:
drivers/net/ethernet/emulex/benet/be.h
drivers/net/netconsole.c
net/bridge/br_private.h
Three mostly trivial conflicts.
The net/bridge/br_private.h conflict was a function signature (argument
addition) change overlapping with the extern removals from Joe Perches.
In drivers/net/netconsole.c we had one change adjusting a printk message
whilst another changed "printk(KERN_INFO" into "pr_info(".
Lastly, the emulex change was a new inline function addition overlapping
with Joe Perches's extern removals.
Signed-off-by: David S. Miller <davem@davemloft.net>
When a memcg is deleted mem_cgroup_reparent_charges() moves charged
memory to the parent memcg. As of v3.11-9444-g3ea67d0 "memcg: add per
cgroup writeback pages accounting" there's bad pointer read. The goal
was to check for counter underflow. The counter is a per cpu counter
and there are two problems with the code:
(1) per cpu access function isn't used, instead a naked pointer is used
which easily causes oops.
(2) the check doesn't sum all cpus
Test:
$ cd /sys/fs/cgroup/memory
$ mkdir x
$ echo 3 > /proc/sys/vm/drop_caches
$ (echo $BASHPID >> x/tasks && exec cat) &
[1] 7154
$ grep ^mapped x/memory.stat
mapped_file 53248
$ echo 7154 > tasks
$ rmdir x
<OOPS>
The fix is to remove the check. It's currently dangerous and isn't
worth fixing it to use something expensive, such as
percpu_counter_sum(), for each reparented page. __this_cpu_read() isn't
enough to fix this because there's no guarantees of the current cpus
count. The only guarantees is that the sum of all per-cpu counter is >=
nr_pages.
Fixes: 3ea67d06e4 ("memcg: add per cgroup writeback pages accounting")
Reported-and-tested-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Sha Zhengju <handai.szj@taobao.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Resolve cherry-picking conflicts:
Conflicts:
mm/huge_memory.c
mm/memory.c
mm/mprotect.c
See this upstream merge commit for more details:
52469b4fcd Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge four more fixes from Andrew Morton.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
lib/scatterlist.c: don't flush_kernel_dcache_page on slab page
mm: memcg: fix test for child groups
mm: memcg: lockdep annotation for memcg OOM lock
mm: memcg: use proper memcg in limit bypass
When memcg code needs to know whether any given memcg has children, it
uses the cgroup child iteration primitives and returns true/false
depending on whether the iteration loop is executed at least once or
not.
Because a cgroup's list of children is RCU protected, these primitives
require the RCU read-lock to be held, which is not the case for all
memcg callers. This results in the following splat when e.g. enabling
hierarchy mode:
WARNING: CPU: 3 PID: 1 at kernel/cgroup.c:3043 css_next_child+0xa3/0x160()
CPU: 3 PID: 1 Comm: systemd Not tainted 3.12.0-rc5-00117-g83f11a9-dirty #18
Hardware name: LENOVO 3680B56/3680B56, BIOS 6QET69WW (1.39 ) 04/26/2012
Call Trace:
dump_stack+0x54/0x74
warn_slowpath_common+0x78/0xa0
warn_slowpath_null+0x1a/0x20
css_next_child+0xa3/0x160
mem_cgroup_hierarchy_write+0x5b/0xa0
cgroup_file_write+0x108/0x2a0
vfs_write+0xbd/0x1e0
SyS_write+0x4c/0xa0
system_call_fastpath+0x16/0x1b
In the memcg case, we only care about children when we are attempting to
modify inheritable attributes interactively. Racing with deletion could
mean a spurious -EBUSY, no problem. Racing with addition is handled
just fine as well through the memcg_create_mutex: if the child group is
not on the list after the mutex is acquired, it won't be initialized
from the parent's attributes until after the unlock.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The memcg OOM lock is a mutex-type lock that is open-coded due to
memcg's special needs. Add annotations for lockdep coverage.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 84235de394 ("fs: buffer: move allocation failure loop into the
allocator") allowed __GFP_NOFAIL allocations to bypass the limit if they
fail to reclaim enough memory for the charge. But because the main test
case was on a 3.2-based system, the patch missed the fact that on newer
kernels the charge function needs to return root_mem_cgroup when
bypassing the limit, and not NULL. This will corrupt whatever memory is
at NULL + percpu pointer offset. Fix this quickly before problems are
reported.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull NUMA balancing memory corruption fixes from Ingo Molnar:
"So these fixes are definitely not something I'd like to sit on, but as
I said to Mel at the KS the timing is quite tight, with Linus planning
v3.12-final within a week.
Fedora-19 is affected:
comet:~> grep NUMA_BALANCING /boot/config-3.11.3-201.fc19.x86_64
CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
CONFIG_NUMA_BALANCING_DEFAULT_ENABLED=y
CONFIG_NUMA_BALANCING=y
AFAICS Ubuntu will be affected as well, once it updates the kernel:
hubble:~> grep NUMA_BALANCING /boot/config-3.8.0-32-generic
CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
CONFIG_NUMA_BALANCING_DEFAULT_ENABLED=y
CONFIG_NUMA_BALANCING=y
These 6 commits are a minimalized set of cherry-picks needed to fix
the memory corruption bugs. All commits are fixes, except "mm: numa:
Sanitize task_numa_fault() callsites" which is a cleanup that made two
followup fixes simpler.
I've done targeted testing with just this SHA1 to try to make sure
there are no cherry-picking artifacts. The original non-cherry-picked
set of fixes were exposed to linux-next for a couple of weeks"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mm: Account for a THP NUMA hinting update as one PTE update
mm: Close races between THP migration and PMD numa clearing
mm: numa: Sanitize task_numa_fault() callsites
mm: Prevent parallel splits during THP migration
mm: Wait for THP migrations to complete during NUMA hinting faults
mm: numa: Do not account for a hinting fault if we raced
Merge three fixes from Andrew Morton.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
memcg: use __this_cpu_sub() to dec stats to avoid incorrect subtrahend casting
percpu: fix this_cpu_sub() subtrahend casting for unsigneds
mm/pagewalk.c: fix walk_page_range() access of wrong PTEs
As of commit 3ea67d06e4 ("memcg: add per cgroup writeback pages
accounting") memcg counter errors are possible when moving charged
memory to a different memcg. Charge movement occurs when processing
writes to memory.force_empty, moving tasks to a memcg with
memcg.move_charge_at_immigrate=1, or memcg deletion.
An example showing error after memory.force_empty:
$ cd /sys/fs/cgroup/memory
$ mkdir x
$ rm /data/tmp/file
$ (echo $BASHPID >> x/tasks && exec mmap_writer /data/tmp/file 1M) &
[1] 13600
$ grep ^mapped x/memory.stat
mapped_file 1048576
$ echo 13600 > tasks
$ echo 1 > x/memory.force_empty
$ grep ^mapped x/memory.stat
mapped_file 4503599627370496
mapped_file should end with 0.
4503599627370496 == 0x10,0000,0000,0000 == 0x100,0000,0000 pages
1048576 == 0x10,0000 == 0x100 pages
This issue only affects the source memcg on 64 bit machines; the
destination memcg counters are correct. So the rmdir case is not too
important because such counters are soon disappearing with the entire
memcg. But the memcg.force_empty and memory.move_charge_at_immigrate=1
cases are larger problems as the bogus counters are visible for the
(possibly long) remaining life of the source memcg.
The problem is due to memcg use of __this_cpu_from(.., -nr_pages), which
is subtly wrong because it subtracts the unsigned int nr_pages (either
-1 or -512 for THP) from a signed long percpu counter. When
nr_pages=-1, -nr_pages=0xffffffff. On 64 bit machines stat->count[idx]
is signed 64 bit. So memcg's attempt to simply decrement a count (e.g.
from 1 to 0) boils down to:
long count = 1
unsigned int nr_pages = 1
count += -nr_pages /* -nr_pages == 0xffff,ffff */
count is now 0x1,0000,0000 instead of 0
The fix is to subtract the unsigned page count rather than adding its
negation. This only works once "percpu: fix this_cpu_sub() subtrahend
casting for unsigneds" is applied to fix this_cpu_sub().
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When walk_page_range walk a memory map's page tables, it'll skip
VM_PFNMAP area, then variable 'next' will to assign to vma->vm_end, it
maybe larger than 'end'. In next loop, 'addr' will be larger than
'next'. Then in /proc/XXXX/pagemap file reading procedure, the 'addr'
will growing forever in pagemap_pte_range, pte_to_pagemap_entry will
access the wrong pte.
BUG: Bad page map in process procrank pte:8437526f pmd:785de067
addr:9108d000 vm_flags:00200073 anon_vma:f0d99020 mapping: (null) index:9108d
CPU: 1 PID: 4974 Comm: procrank Tainted: G B W O 3.10.1+ #1
Call Trace:
dump_stack+0x16/0x18
print_bad_pte+0x114/0x1b0
vm_normal_page+0x56/0x60
pagemap_pte_range+0x17a/0x1d0
walk_page_range+0x19e/0x2c0
pagemap_read+0x16e/0x200
vfs_read+0x84/0x150
SyS_read+0x4a/0x80
syscall_call+0x7/0xb
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Signed-off-by: Chen LinX <linx.z.chen@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org> [3.10.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I've seen a fair number of issues with kswapd and other processes
appearing to get stuck in v3.12-rc. Using sysrq-p many times seems to
indicate that it gets stuck somewhere in list_lru_walk_node(), called
from prune_icache_sb() and super_cache_scan().
I never seem to be able to trigger a calltrace for functions above that
point.
So I decided to add the following to super_cache_scan():
@@ -81,10 +81,14 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
inodes = list_lru_count_node(&sb->s_inode_lru, sc->nid);
dentries = list_lru_count_node(&sb->s_dentry_lru, sc->nid);
total_objects = dentries + inodes + fs_objects + 1;
+printk("%s:%u: %s: dentries %lu inodes %lu total %lu\n", current->comm, current->pid, __func__, dentries, inodes, total_objects);
/* proportion the scan between the caches */
dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
inodes = mult_frac(sc->nr_to_scan, inodes, total_objects);
+printk("%s:%u: %s: dentries %lu inodes %lu\n", current->comm, current->pid, __func__, dentries, inodes);
+BUG_ON(dentries == 0);
+BUG_ON(inodes == 0);
/*
* prune the dcache first as the icache is pinned by it, then
@@ -99,7 +103,7 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
freed += sb->s_op->free_cached_objects(sb, fs_objects,
sc->nid);
}
-
+printk("%s:%u: %s: dentries %lu inodes %lu freed %lu\n", current->comm, current->pid, __func__, dentries, inodes, freed);
drop_super(sb);
return freed;
}
and shortly thereafter, having applied some pressure, I got this:
update-apt-xapi:1616: super_cache_scan: dentries 25632 inodes 2 total 25635
update-apt-xapi:1616: super_cache_scan: dentries 1023 inodes 0
------------[ cut here ]------------
Kernel BUG at c0101994 [verbose debug info unavailable]
Internal error: Oops - BUG: 0 [#3] SMP ARM
Modules linked in: fuse rfcomm bnep bluetooth hid_cypress
CPU: 0 PID: 1616 Comm: update-apt-xapi Tainted: G D 3.12.0-rc7+ #154
task: daea1200 ti: c3bf8000 task.ti: c3bf8000
PC is at super_cache_scan+0x1c0/0x278
LR is at trace_hardirqs_on+0x14/0x18
Process update-apt-xapi (pid: 1616, stack limit = 0xc3bf8240)
...
Backtrace:
(super_cache_scan) from [<c00cd69c>] (shrink_slab+0x254/0x4c8)
(shrink_slab) from [<c00d09a0>] (try_to_free_pages+0x3a0/0x5e0)
(try_to_free_pages) from [<c00c59cc>] (__alloc_pages_nodemask+0x5)
(__alloc_pages_nodemask) from [<c00e07c0>] (__pte_alloc+0x2c/0x13)
(__pte_alloc) from [<c00e3a70>] (handle_mm_fault+0x84c/0x914)
(handle_mm_fault) from [<c001a4cc>] (do_page_fault+0x1f0/0x3bc)
(do_page_fault) from [<c001a7b0>] (do_translation_fault+0xac/0xb8)
(do_translation_fault) from [<c000840c>] (do_DataAbort+0x38/0xa0)
(do_DataAbort) from [<c00133f8>] (__dabt_usr+0x38/0x40)
Notice that we had a very low number of inodes, which were reduced to
zero my mult_frac().
Now, prune_icache_sb() calls list_lru_walk_node() passing that number of
inodes (0) into that as the number of objects to scan:
long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
int nid)
{
LIST_HEAD(freeable);
long freed;
freed = list_lru_walk_node(&sb->s_inode_lru, nid, inode_lru_isolate,
&freeable, &nr_to_scan);
which does:
unsigned long
list_lru_walk_node(struct list_lru *lru, int nid, list_lru_walk_cb isolate,
void *cb_arg, unsigned long *nr_to_walk)
{
struct list_lru_node *nlru = &lru->node[nid];
struct list_head *item, *n;
unsigned long isolated = 0;
spin_lock(&nlru->lock);
restart:
list_for_each_safe(item, n, &nlru->list) {
enum lru_status ret;
/*
* decrement nr_to_walk first so that we don't livelock if we
* get stuck on large numbesr of LRU_RETRY items
*/
if (--(*nr_to_walk) == 0)
break;
So, if *nr_to_walk was zero when this function was entered, that means
we're wanting to operate on (~0UL)+1 objects - which might as well be
infinite.
Clearly this is not correct behaviour. If we think about the behaviour
of this function when *nr_to_walk is 1, then clearly it's wrong - we
decrement first and then test for zero - which results in us doing
nothing at all. A post-decrement would give the desired behaviour -
we'd try to walk one object and one object only if *nr_to_walk were one.
It also gives the correct behaviour for zero - we exit at this point.
Fixes: 5cedf721a7 ("list_lru: fix broken LRU_RETRY behaviour")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
[ Modified to make sure we never underflow the count: this function gets
called in a loop, so the 0 -> ~0ul transition is dangerous - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no 'strcut freelist', but codes use pointer to 'struct freelist'.
Although compiler doesn't complain anything about this wrong usage and
codes work fine, but fixing it is better.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
After using struct page as slab management, we should not call
kmemleak_scan_area(), since struct page isn't the tracking object of
kmemleak. Without this patch and if CONFIG_DEBUG_KMEMLEAK is enabled,
so many kmemleak warnings are printed.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
A THP PMD update is accounted for as 512 pages updated in vmstat. This is
large difference when estimating the cost of automatic NUMA balancing and
can be misleading when comparing results that had collapsed versus split
THP. This patch addresses the accounting issue.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-10-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
THP migration uses the page lock to guard against parallel allocations
but there are cases like this still open
Task A Task B
--------------------- ---------------------
do_huge_pmd_numa_page do_huge_pmd_numa_page
lock_page
mpol_misplaced == -1
unlock_page
goto clear_pmdnuma
lock_page
mpol_misplaced == 2
migrate_misplaced_transhuge
pmd = pmd_mknonnuma
set_pmd_at
During hours of testing, one crashed with weird errors and while I have
no direct evidence, I suspect something like the race above happened.
This patch extends the page lock to being held until the pmd_numa is
cleared to prevent migration starting in parallel while the pmd_numa is
being cleared. It also flushes the old pmd entry and orders pagetable
insertion before rmap insertion.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-9-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are three callers of task_numa_fault():
- do_huge_pmd_numa_page():
Accounts against the current node, not the node where the
page resides, unless we migrated, in which case it accounts
against the node we migrated to.
- do_numa_page():
Accounts against the current node, not the node where the
page resides, unless we migrated, in which case it accounts
against the node we migrated to.
- do_pmd_numa_page():
Accounts not at all when the page isn't migrated, otherwise
accounts against the node we migrated towards.
This seems wrong to me; all three sites should have the same
sementaics, furthermore we should accounts against where the page
really is, we already know where the task is.
So modify all three sites to always account; we did after all receive
the fault; and always account to where the page is after migration,
regardless of success.
They all still differ on when they clear the PTE/PMD; ideally that
would get sorted too.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-8-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
THP migrations are serialised by the page lock but on its own that does
not prevent THP splits. If the page is split during THP migration then
the pmd_same checks will prevent page table corruption but the unlock page
and other fix-ups potentially will cause corruption. This patch takes the
anon_vma lock to prevent parallel splits during migration.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-7-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The locking for migrating THP is unusual. While normal page migration
prevents parallel accesses using a migration PTE, THP migration relies on
a combination of the page_table_lock, the page lock and the existance of
the NUMA hinting PTE to guarantee safety but there is a bug in the scheme.
If a THP page is currently being migrated and another thread traps a
fault on the same page it checks if the page is misplaced. If it is not,
then pmd_numa is cleared. The problem is that it checks if the page is
misplaced without holding the page lock meaning that the racing thread
can be migrating the THP when the second thread clears the NUMA bit
and faults a stale page.
This patch checks if the page is potentially being migrated and stalls
using the lock_page if it is potentially being migrated before checking
if the page is misplaced or not.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-6-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If another task handled a hinting fault in parallel then do not double
account for it.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-5-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move all kmemleak calls into hook functions, and make it so
that all hooks (both inside and outside of #ifdef CONFIG_SLUB_DEBUG)
call the appropriate kmemleak routines. This allows for kmemleak
to be configured independently of slub debug features.
It also fixes a bug where kmemleak was only partially enabled in some
configurations.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Roman Bobniev <Roman.Bobniev@sonymobile.com>
Signed-off-by: Tim Bird <tim.bird@sonymobile.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now, bufctl is not proper name to this array.
So change it.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now, virt_to_page(page->s_mem) is same as the page,
because slab use this structure for management.
So remove useless statement.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now, there are a few field in struct slab, so we can overload these
over struct page. This will save some memory and reduce cache footprint.
After this change, slabp_cache and slab_size no longer related to
a struct slab, so rename them as freelist_cache and freelist_size.
These changes are just mechanical ones and there is no functional change.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now, free in struct slab is same meaning as inuse.
So, remove both and replace them with active.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
It's useless now, so remove it.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now, we changed the management method of free objects of the slab and
there is no need to use special value, BUFCTL_END, BUFCTL_FREE and
BUFCTL_ACTIVE. So remove them.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Current free objects management method of the slab is weird, because
it touch random position of the array of kmem_bufctl_t when we try to
get free object. See following example.
struct slab's free = 6
kmem_bufctl_t array: 1 END 5 7 0 4 3 2
To get free objects, we access this array with following pattern.
6 -> 3 -> 7 -> 2 -> 5 -> 4 -> 0 -> 1 -> END
If we have many objects, this array would be larger and be not in the same
cache line. It is not good for performance.
We can do same thing through more easy way, like as the stack.
Only thing we have to do is to maintain stack top to free object. I use
free field of struct slab for this purpose. After that, if we need to get
an object, we can get it at stack top and manipulate top pointer.
That's all. This method already used in array_cache management.
Following is an access pattern when we use this method.
struct slab's free = 0
kmem_bufctl_t array: 6 3 7 2 5 4 0 1
To get free objects, we access this array with following pattern.
0 -> 1 -> 2 -> 3 -> 4 -> 5 -> 6 -> 7
This may help cache line footprint if slab has many objects, and,
in addition, this makes code much much simpler.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
If we use 'struct page' of first page as 'struct slab', there is no
advantage not to use __GFP_COMP. So use __GFP_COMP flag for all the cases.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
This is trivial change, just use well-defined macro.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
With build-time size checking, we can overload the RCU head over the LRU
of struct page to free pages of a slab in rcu context. This really help to
implement to overload the struct slab over the struct page and this
eventually reduce memory usage and cache footprint of the SLAB.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
We can get cachep using page in struct slab_rcu, so remove it.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
We can get nodeid using address translation, so this field is not useful.
Therefore, remove it.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Now there is no user colouroff, so remove it.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
It is more understandable that kmem_getpages() return struct page.
And, with this, we can reduce one translation from virt addr to page and
makes better code than before. Below is a change of this patch.
* Before
text data bss dec hex filename
22123 23434 4 45561 b1f9 mm/slab.o
* After
text data bss dec hex filename
22074 23434 4 45512 b1c8 mm/slab.o
And this help following patch to remove struct slab's colouroff.
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
We checked pfmemalloc by slab unit, not page unit. You can see this
in is_slab_pfmemalloc(). So other pages don't need to be set/cleared
pfmemalloc.
And, therefore we should check pfmemalloc in page flag of first page,
but current implementation don't do that. virt_to_head_page(obj) just
return 'struct page' of that object, not one of first page, since the SLAB
don't use __GFP_COMP when CONFIG_MMU. To get 'struct page' of first page,
we first get a slab and try to get it via virt_to_head_page(slab->s_mem).
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Pekka Enberg <penberg@iki.fi>
Conflicts:
drivers/net/usb/qmi_wwan.c
include/net/dst.h
Trivial merge conflicts, both were overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the pointers in struct cg_proto with actual data fields and kill
struct tcp_memcontrol as it is not fully redundant.
This removes a confusing, unnecessary layer of abstraction.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Revert commit 1ecfd533f4 ("mm/mremap.c: call pud_free() after fail
calling pmd_alloc()").
The original code was correct: pud_alloc(), pmd_alloc(), pte_alloc_map()
ensure that the pud, pmd, pt is already allocated, and seldom do they
need to allocate; on failure, upper levels are freed if appropriate by
the subsequent do_munmap(). Whereas commit 1ecfd533f4 did an
unconditional pud_free() of a most-likely still-in-use pud: saved only
by the near-impossiblity of pmd_alloc() failing.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Occasionally we hit the BUG_ON(pmd_trans_huge(*pmd)) at the end of
__split_huge_page_pmd(): seen when doing madvise(,,MADV_DONTNEED).
It's invalid: we don't always have down_write of mmap_sem there: a racing
do_huge_pmd_wp_page() might have copied-on-write to another huge page
before our split_huge_page() got the anon_vma lock.
Forget the BUG_ON, just go back and try again if this happens.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix race between swapoff and swapon. Swapoff used old_block_size from
swap_info outside of swapon_mutex so it could be overwritten by
concurrent swapon.
The race has visible effect only if more than one swap block device
exists with different block sizes (e.g. /dev/sda1 with block size 4096
and /dev/sdb1 with 512). In such case it leads to setting the blocksize
of swapped off device with wrong blocksize.
The bug can be triggered with multiple concurrent swapoff and swapon:
0. Swap for some device is on.
1. swapoff:
First the swapoff is called on this device and "struct swap_info_struct
*p" is assigned. This is done under swap_lock however this lock is
released for the call try_to_unuse().
2. swapon:
After the assignment above (and before acquiring swapon_mutex &
swap_lock by swapoff) the swapon is called on the same device.
The p->old_block_size is assigned to the value of block_size the device.
This block size should be the same as previous but sometimes it is not.
The swapon ends successfully.
3. swapoff:
Swapoff resumes, grabs the locks and mutex and continues to disable this
swap device. Now it sets the block size to value taken from swap_info
which was overwritten by swapon in 2.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: Weijie Yang <weijie.yang.kh@gmail.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Minchan Kim <minchan@kernel.org>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Toralf runs trinity on UML/i386. After some time it hangs and the last
message line is
BUG: soft lockup - CPU#0 stuck for 22s! [trinity-child0:1521]
It's found that pages_dirtied becomes very large. More than 1000000000
pages in this case:
period = HZ * pages_dirtied / task_ratelimit;
BUG_ON(pages_dirtied > 2000000000);
BUG_ON(pages_dirtied > 1000000000); <---------
UML debug printf shows that we got negative pause here:
ick: pause : -984
ick: pages_dirtied : 0
ick: task_ratelimit: 0
pause:
+ if (pause < 0) {
+ extern int printf(char *, ...);
+ printf("ick : pause : %li\n", pause);
+ printf("ick: pages_dirtied : %lu\n", pages_dirtied);
+ printf("ick: task_ratelimit: %lu\n", task_ratelimit);
+ BUG_ON(1);
+ }
trace_balance_dirty_pages(bdi,
Since pause is bounded by [min_pause, max_pause] where min_pause is also
bounded by max_pause. It's suspected and demonstrated that the
max_pause calculation goes wrong:
ick: pause : -717
ick: min_pause : -177
ick: max_pause : -717
ick: pages_dirtied : 14
ick: task_ratelimit: 0
The problem lies in the two "long = unsigned long" assignments in
bdi_max_pause() which might go negative if the highest bit is 1, and the
min_t(long, ...) check failed to protect it falling under 0. Fix all of
them by using "unsigned long" throughout the function.
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Tested-by: Toralf Förster <toralf.foerster@gmx.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Richard Weinberger <richard@nod.at>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Buffer allocation has a very crude indefinite loop around waking the
flusher threads and performing global NOFS direct reclaim because it can
not handle allocation failures.
The most immediate problem with this is that the allocation may fail due
to a memory cgroup limit, where flushers + direct reclaim might not make
any progress towards resolving the situation at all. Because unlike the
global case, a memory cgroup may not have any cache at all, only
anonymous pages but no swap. This situation will lead to a reclaim
livelock with insane IO from waking the flushers and thrashing unrelated
filesystem cache in a tight loop.
Use __GFP_NOFAIL allocations for buffers for now. This makes sure that
any looping happens in the page allocator, which knows how to
orchestrate kswapd, direct reclaim, and the flushers sensibly. It also
allows memory cgroups to detect allocations that can't handle failure
and will allow them to ultimately bypass the limit if reclaim can not
make progress.
Reported-by: azurIt <azurit@pobox.sk>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 3812c8c8f3 ("mm: memcg: do not trap chargers with full
callstack on OOM") assumed that only a few places that can trigger a
memcg OOM situation do not return VM_FAULT_OOM, like optional page cache
readahead. But there are many more and it's impractical to annotate
them all.
First of all, we don't want to invoke the OOM killer when the failed
allocation is gracefully handled, so defer the actual kill to the end of
the fault handling as well. This simplifies the code quite a bit for
added bonus.
Second, since a failed allocation might not be the abrupt end of the
fault, the memcg OOM handler needs to be re-entrant until the fault
finishes for subsequent allocation attempts. If an allocation is
attempted after the task already OOMed, allow it to bypass the limit so
that it can quickly finish the fault and invoke the OOM killer.
Reported-by: azurIt <azurit@pobox.sk>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 11feeb4980 ("kvm: optimize away THP checks in
kvm_is_mmio_pfn()") introduced a memory leak when KVM is run on gigantic
compound pages.
That commit depends on the assumption that PG_reserved is identical for
all head and tail pages of a compound page. So that if get_user_pages
returns a tail page, we don't need to check the head page in order to
know if we deal with a reserved page that requires different
refcounting.
The assumption that PG_reserved is the same for head and tail pages is
certainly correct for THP and regular hugepages, but gigantic hugepages
allocated through bootmem don't clear the PG_reserved on the tail pages
(the clearing of PG_reserved is done later only if the gigantic hugepage
is freed).
This patch corrects the gigantic compound page initialization so that we
can retain the optimization in 11feeb4980. The cacheline was already
modified in order to set PG_tail so this won't affect the boot time of
large memory systems.
[akpm@linux-foundation.org: tweak comment layout and grammar]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: andy123 <ajs124.ajs124@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
zswap_tree is not freed when swapoff, and it got re-kmalloced in swapon,
so a memory leak occurs.
Free the memory of zswap_tree in zswap_frontswap_invalidate_area().
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
From: Weijie Yang <weijie.yang@samsung.com>
Subject: mm/zswap: bugfix: memory leak when invalidate and reclaim occur concurrently
Consider the following scenario:
thread 0: reclaim entry x (get refcount, but not call zswap_get_swap_cache_page)
thread 1: call zswap_frontswap_invalidate_page to invalidate entry x.
finished, entry x and its zbud is not freed as its refcount != 0
now, the swap_map[x] = 0
thread 0: now call zswap_get_swap_cache_page
swapcache_prepare return -ENOENT because entry x is not used any more
zswap_get_swap_cache_page return ZSWAP_SWAPCACHE_NOMEM
zswap_writeback_entry do nothing except put refcount
Now, the memory of zswap_entry x and its zpage leak.
Modify:
- check the refcount in fail path, free memory if it is not referenced.
- use ZSWAP_SWAPCACHE_FAIL instead of ZSWAP_SWAPCACHE_NOMEM as the fail path
can be not only caused by nomem but also by invalidate.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If page migration is turned on in config and the page is migrating, we
may lose the soft dirty bit. If fork and mprotect are called on
migrating pages (once migration is complete) pages do not obtain the
soft dirty bit in the correspond pte entries. Fix it adding an
appropriate test on swap entries.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should clear the page's private flag when returing the page to the
hugepage pool. Otherwise, marked hugepage can be allocated to the user
who tries to allocate the non-reserved hugepage. If this user fail to
map this hugepage, he would try to return the page to the hugepage pool.
Since this page has a private flag, resv_huge_pages would mistakenly
increase. This patch fixes this situation.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
for_each_online_cpu() needs the protection of {get,put}_online_cpus() so
cpu_online_mask doesn't change during the iteration.
cpu_hotplug.lock is held while a cpu is going down, it's a coarse lock
that is used kernel-wide to synchronize cpu hotplug activity. Memcg has
a cpu hotplug notifier, called while there may not be any cpu hotplug
refcounts, which drains per-cpu event counts to memcg->nocpu_base.events
to maintain a cumulative event count as cpus disappear. Without
get_online_cpus() in mem_cgroup_read_events(), it's possible to account
for the event count on a dying cpu twice, and this value may be
significantly large.
In fact, all memcg->pcp_counter_lock use should be nested by
{get,put}_online_cpus().
This fixes that issue and ensures the reported statistics are not vastly
over-reported during cpu hotplug.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull SLAB fix from Pekka Enberg:
"A regression fix for overly eager slab cache name checks"
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
slab_common: Do not check for duplicate slab names
Shared faults can lead to lots of unnecessary page migrations,
slowing down the system, and causing private faults to hit the
per-pgdat migration ratelimit.
This patch adds sysctl numa_balancing_migrate_deferred, which specifies
how many shared page migrations to skip unconditionally, after each page
migration that is skipped because it is a shared fault.
This reduces the number of page migrations back and forth in
shared fault situations. It also gives a strong preference to
the tasks that are already running where most of the memory is,
and to moving the other tasks to near the memory.
Testing this with a much higher scan rate than the default
still seems to result in fewer page migrations than before.
Memory seems to be somewhat better consolidated than previously,
with multi-instance specjbb runs on a 4 node system.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-62-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the scan rate code working (at least for multi-instance specjbb),
the large hammer that is "sched: Do not migrate memory immediately after
switching node" can be replaced with something smarter. Revert temporarily
migration disabling and all traces of numa_migrate_seq.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-61-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Adjust numa_scan_period in task_numa_placement, depending on how much
useful work the numa code can do. The more local faults there are in a
given scan window the longer the period (and hence the slower the scan rate)
during the next window. If there are excessive shared faults then the scan
period will decrease with the amount of scaling depending on whether the
ratio of shared/private faults. If the preferred node changes then the
scan rate is reset to recheck if the task is properly placed.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-59-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Due to the way the pid is truncated, and tasks are moved between
CPUs by the scheduler, it is possible for the current task_numa_fault
to group together tasks that do not actually share memory together.
This patch adds a few easy sanity checks to task_numa_fault, joining
tasks together if they share the same tsk->mm, or if the fault was on
a page with an elevated mapcount, in a shared VMA.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-57-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the THP migration races closed it is still possible to occasionally
see corruption. The problem is related to handling PMD pages in batch.
When a page fault is handled it can be assumed that the page being
faulted will also be flushed from the TLB. The same flushing does not
happen when handling PMD pages in batch. Fixing is straight forward but
there are a number of reasons not to
1. Multiple TLB flushes may have to be sent depending on what pages get
migrated
2. The handling of PMDs in batch means that faults get accounted to
the task that is handling the fault. While care is taken to only
mark PMDs where the last CPU and PID match it can still have problems
due to PID truncation when matching PIDs.
3. Batching on the PMD level may reduce faults but setting pmd_numa
requires taking a heavy lock that can contend with THP migration
and handling the fault requires the release/acquisition of the PTL
for every page migrated. It's still pretty heavy.
PMD batch handling is not something that people ever have been happy
with. This patch removes it and later patches will deal with the
additional fault overhead using more installigent migrate rate adaption.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-48-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
And here's a little something to make sure not the whole world ends up
in a single group.
As while we don't migrate shared executable pages, we do scan/fault on
them. And since everybody links to libc, everybody ends up in the same
group.
Suggested-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1381141781-10992-47-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After page migration, the new page has the nidpid unset. This makes
every fault on a recently migrated page look like a first numa fault,
leading to another page migration.
Copying over the nidpid at page migration time should prevent erroneous
migrations of recently migrated pages.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-46-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While parallel applications tend to align their data on the cache
boundary, they tend not to align on the page or THP boundary.
Consequently tasks that partition their data can still "false-share"
pages presenting a problem for optimal NUMA placement.
This patch uses NUMA hinting faults to chain tasks together into
numa_groups. As well as storing the NID a task was running on when
accessing a page a truncated representation of the faulting PID is
stored. If subsequent faults are from different PIDs it is reasonable
to assume that those two tasks share a page and are candidates for
being grouped together. Note that this patch makes no scheduling
decisions based on the grouping information.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1381141781-10992-44-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change the per page last fault tracking to use cpu,pid instead of
nid,pid. This will allow us to try and lookup the alternate task more
easily. Note that even though it is the cpu that is store in the page
flags that the mpol_misplaced decision is still based on the node.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1381141781-10992-43-git-send-email-mgorman@suse.de
[ Fixed build failure on 32-bit systems. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Base page PMD faulting is meant to batch handle NUMA hinting faults from
PTEs. However, even is no PTE faults would ever be handled within a
range the kernel still traps PMD hinting faults. This patch avoids the
overhead.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-37-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is a 90% regression observed with a large Oracle performance test
on a 4 node system. Profiles indicated that the overhead was due to
contention on sp_lock when looking up shared memory policies. These
policies do not have the appropriate flags to allow them to be
automatically balanced so trapping faults on them is pointless. This
patch skips VMAs that do not have MPOL_F_MOF set.
[riel@redhat.com: Initial patch]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-and-tested-by: Joe Mario <jmario@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-32-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The load balancer can move tasks between nodes and does not take NUMA
locality into account. With automatic NUMA balancing this may result in the
tasks working set being migrated to the new node. However, as the fault
buffer will still store faults from the old node the schduler may decide to
reset the preferred node and migrate the task back resulting in more
migrations.
The ideal would be that the scheduler did not migrate tasks with a heavy
memory footprint but this may result nodes being overloaded. We could
also discard the fault information on task migration but this would still
cause all the tasks working set to be migrated. This patch simply avoids
migrating the memory for a short time after a task is migrated.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-31-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ideally it would be possible to distinguish between NUMA hinting faults that
are private to a task and those that are shared. If treated identically
there is a risk that shared pages bounce between nodes depending on
the order they are referenced by tasks. Ultimately what is desirable is
that task private pages remain local to the task while shared pages are
interleaved between sharing tasks running on different nodes to give good
average performance. This is further complicated by THP as even
applications that partition their data may not be partitioning on a huge
page boundary.
To start with, this patch assumes that multi-threaded or multi-process
applications partition their data and that in general the private accesses
are more important for cpu->memory locality in the general case. Also,
no new infrastructure is required to treat private pages properly but
interleaving for shared pages requires additional infrastructure.
To detect private accesses the pid of the last accessing task is required
but the storage requirements are a high. This patch borrows heavily from
Ingo Molnar's patch "numa, mm, sched: Implement last-CPU+PID hash tracking"
to encode some bits from the last accessing task in the page flags as
well as the node information. Collisions will occur but it is better than
just depending on the node information. Node information is then used to
determine if a page needs to migrate. The PID information is used to detect
private/shared accesses. The preferred NUMA node is selected based on where
the maximum number of approximately private faults were measured. Shared
faults are not taken into consideration for a few reasons.
First, if there are many tasks sharing the page then they'll all move
towards the same node. The node will be compute overloaded and then
scheduled away later only to bounce back again. Alternatively the shared
tasks would just bounce around nodes because the fault information is
effectively noise. Either way accounting for shared faults the same as
private faults can result in lower performance overall.
The second reason is based on a hypothetical workload that has a small
number of very important, heavily accessed private pages but a large shared
array. The shared array would dominate the number of faults and be selected
as a preferred node even though it's the wrong decision.
The third reason is that multiple threads in a process will race each
other to fault the shared page making the fault information unreliable.
Signed-off-by: Mel Gorman <mgorman@suse.de>
[ Fix complication error when !NUMA_BALANCING. ]
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-30-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently automatic NUMA balancing is unable to distinguish between false
shared versus private pages except by ignoring pages with an elevated
page_mapcount entirely. This avoids shared pages bouncing between the
nodes whose task is using them but that is ignored quite a lot of data.
This patch kicks away the training wheels in preparation for adding support
for identifying shared/private pages is now in place. The ordering is so
that the impact of the shared/private detection can be easily measured. Note
that the patch does not migrate shared, file-backed within vmas marked
VM_EXEC as these are generally shared library pages. Migrating such pages
is not beneficial as there is an expectation they are read-shared between
caches and iTLB and iCache pressure is generally low.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-28-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ideally it would be possible to distinguish between NUMA hinting faults
that are private to a task and those that are shared. This patch prepares
infrastructure for separately accounting shared and private faults by
allocating the necessary buffers and passing in relevant information. For
now, all faults are treated as private and detection will be introduced
later.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-26-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The zero page is not replicated between nodes and is often shared between
processes. The data is read-only and likely to be cached in local CPUs
if heavily accessed meaning that the remote memory access cost is less
of a concern. This patch prevents trapping faults on the zero pages. For
tasks using the zero page this will reduce the number of PTE updates,
TLB flushes and hinting faults.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
[ Correct use of is_huge_zero_page]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-13-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rik van Riel