At bootup we run measurements to calculate the best threshold for when we
should be using full TLB flushes instead of just flushing a specific amount of
TLB entries. This performance test is run over the kernel text segment.
But running this TLB performance test on the kernel text segment turned out to
crash some SMP machines when the kernel text pages were mapped as huge pages.
To avoid those crashes this patch simply skips this test on some SMP machines
and calculates an optimal threshold based on the maximum number of available
TLB entries and number of online CPUs.
On a technical side, this seems to happen:
The TLB measurement code uses flush_tlb_kernel_range() to flush specific TLB
entries with a page size of 4k (pdtlb 0(sr1,addr)). On UP systems this purge
instruction seems to work without problems even if the pages were mapped as
huge pages. But on SMP systems the TLB purge instruction is broadcasted to
other CPUs. Those CPUs then crash the machine because the page size is not as
expected. C8000 machines with PA8800/PA8900 CPUs were not affected by this
problem, because the required cache coherency prohibits to use huge pages at
all. Sadly I didn't found any documentation about this behaviour, so this
finding is purely based on testing with phyiscal SMP machines (A500-44 and
J5000, both were 2-way boxes).
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Helge Deller <deller@gmx.de>
We have four routines in pacache.S that use temporary alias pages:
copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
flush_icache_page_asm(). copy_user_page_asm() and clear_user_page_asm()
don't purge the TLB entry used for the operation.
flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.
Presumably, this was thought to optimize TLB use. However, the
operation is quite heavy weight on PA 1.X processors as we need to take
the TLB lock and a TLB broadcast is sent to all processors.
This patch removes the purges from flush_dcache_page_asm() and
flush_icache_page_asm.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Helge Deller <deller@gmx.de>
The attached change interchanges the order of purging the TLB and
setting the corresponding page table entry. TLB purges are strongly
ordered. It occurred to me one night that setting the PTE first might
have subtle ordering issues on SMP machines and cause random memory
corruption.
A TLB lock guards the insertion of user TLB entries. So after the TLB
is purged, a new entry can't be inserted until the lock is released.
This ensures that the new PTE value is used when the lock is released.
Since making this change, no random segmentation faults have been
observed on the Debian hppa buildd servers.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Helge Deller <deller@gmx.de>
This patch exports the sender chronograph stats via the socket
SO_TIMESTAMPING channel. Currently we can instrument how long a
particular application unit of data was queued in TCP by tracking
SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having
these sender chronograph stats exported simultaneously along with
these timestamps allow further breaking down the various sender
limitation. For example, a video server can tell if a particular
chunk of video on a connection takes a long time to deliver because
TCP was experiencing small receive window. It is not possible to
tell before this patch without packet traces.
To prepare these stats, the user needs to set
SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags
while requesting other SOF_TIMESTAMPING TX timestamps. When the
timestamps are available in the error queue, the stats are returned
in a separate control message of type SCM_TIMESTAMPING_OPT_STATS,
in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME,
TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond.
Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the second issue I noticed in reviewing the parisc TLB code.
The fic instruction may use either the instruction or data TLB in
flushing the instruction cache. Thus, on machines with a split TLB, we
should also flush the data TLB after setting up the temporary alias
registers.
Although this has no functional impact, I changed the pdtlb and pitlb
instructions to consistently use the index register %r0. These
instructions do not support integer displacements.
Tested on rp3440 and c8000.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Helge Deller <deller@gmx.de>
We are still troubled by occasional random segmentation faults and
memory memory corruption on SMP machines. The causes quite a few
package builds to fail on the Debian buildd machines for parisc. When
gcc-6 failed to build three times in a row, I looked again at the TLB
related code. I found a couple of issues. This is the first.
In general, we need to ensure page table updates and corresponding TLB
purges are atomic. The attached patch fixes an instance in pci-dma.c
where the page table update was not guarded by the TLB lock.
Tested on rp3440 and c8000. So far, no further random segmentation
faults have been observed.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Helge Deller <deller@gmx.de>
Drop the open-coded sched_clock() function and replace it by the provided
GENERIC_SCHED_CLOCK implementation. We have seen quite some hung tasks in the
past, which seem to be fixed by this patch.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Helge Deller <deller@gmx.de>
No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As there are no users left, we can remove cpu_relax_lowlatency()
implementations from every architecture.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Cc: <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For spinning loops people do often use barrier() or cpu_relax().
For most architectures cpu_relax and barrier are the same, but on
some architectures cpu_relax can add some latency.
For example on power,sparc64 and arc, cpu_relax can shift the CPU
towards other hardware threads in an SMT environment.
On s390 cpu_relax does even more, it uses an hypercall to the
hypervisor to give up the timeslice.
In contrast to the SMT yielding this can result in larger latencies.
In some places this latency is unwanted, so another variant
"cpu_relax_lowlatency" was introduced. Before this is used in more
and more places, lets revert the logic and provide a cpu_relax_yield
that can be called in places where yielding is more important than
latency. By default this is the same as cpu_relax on all architectures.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We have one critical section in the syscall entry path in which we switch from
the userspace stack to kernel stack. In the event of an external interrupt, the
interrupt code distinguishes between those two states by analyzing the value of
sr7. If sr7 is zero, it uses the kernel stack. Therefore it's important, that
the value of sr7 is in sync with the currently enabled stack.
This patch now disables interrupts while executing the critical section. This
prevents the interrupt handler to possibly see an inconsistent state which in
the worst case can lead to crashes.
Interestingly, in the syscall exit path interrupts were already disabled in the
critical section which switches back to the userspace stack.
Cc: <stable@vger.kernel.org>
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
There is no need to trash sr2 and sr3 in the Light-weight syscall (LWS). sr2
already points to kernel space (it's zero in userspace, otherwise syscalls
wouldn't work), and since the LWS code is executed in userspace, we can simply
ignore to preload sr3.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Recent changes to printk require KERN_CONT uses to continue logging messages.
So add KERN_CONT to output of device inventory.
Signed-off-by: Helge Deller <deller@gmx.de>
Its all generic atomic_long_t stuff now.
Tested-by: Jason Low <jason.low2@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull parisc fixes from Helge Deller:
"Some final updates and fixes for this merge window for the parisc
architecture. Changes include:
- Fix boot problems with new memblock allocator on rp3410 machine
- Increase initial kernel mapping size for 32- and 64-bit kernels,
this allows to boot bigger kernels which have many modules built-in
- Fix kernel layout regarding __gp and move exception table into RO
section
- Show trap names in crashes, use extable.h header instead of
module.h"
* 'parisc-4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Show trap name in kernel crash
parisc: Zero-initialize newly alloced memblock
parisc: Move exception table into read-only section
parisc: Fix kernel memory layout regarding position of __gp
parisc: Increase initial kernel mapping size
parisc: Migrate exception table users off module.h and onto extable.h
Commit 4fe9e1d957 ("parisc: Drop bootmem and switch to memblock")
switched to the memblock allocator, but missed to zero-initialize the
newly allocated memblocks. This lead to crashes on some machines like
the rp3410.
Fixes: 4fe9e1d957 ("parisc: Drop bootmem and switch to memblock")
Signed-off-by: Helge Deller <deller@gmx.de>
Pull misc vfs updates from Al Viro:
"Assorted misc bits and pieces.
There are several single-topic branches left after this (rename2
series from Miklos, current_time series from Deepa Dinamani, xattr
series from Andreas, uaccess stuff from from me) and I'd prefer to
send those separately"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (39 commits)
proc: switch auxv to use of __mem_open()
hpfs: support FIEMAP
cifs: get rid of unused arguments of CIFSSMBWrite()
posix_acl: uapi header split
posix_acl: xattr representation cleanups
fs/aio.c: eliminate redundant loads in put_aio_ring_file
fs/internal.h: add const to ns_dentry_operations declaration
compat: remove compat_printk()
fs/buffer.c: make __getblk_slow() static
proc: unsigned file descriptors
fs/file: more unsigned file descriptors
fs: compat: remove redundant check of nr_segs
cachefiles: Fix attempt to read i_blocks after deleting file [ver #2]
cifs: don't use memcpy() to copy struct iov_iter
get rid of separate multipage fault-in primitives
fs: Avoid premature clearing of capabilities
fs: Give dentry to inode_change_ok() instead of inode
fuse: Propagate dentry down to inode_change_ok()
ceph: Propagate dentry down to inode_change_ok()
xfs: Propagate dentry down to inode_change_ok()
...
Pull protection keys syscall interface from Thomas Gleixner:
"This is the final step of Protection Keys support which adds the
syscalls so user space can actually allocate keys and protect memory
areas with them. Details and usage examples can be found in the
documentation.
The mm side of this has been acked by Mel"
* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/pkeys: Update documentation
x86/mm/pkeys: Do not skip PKRU register if debug registers are not used
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
x86/pkeys: Add self-tests
x86/pkeys: Allow configuration of init_pkru
x86/pkeys: Default to a restrictive init PKRU
pkeys: Add details of system call use to Documentation/
generic syscalls: Wire up memory protection keys syscalls
x86: Wire up protection keys system calls
x86/pkeys: Allocation/free syscalls
x86/pkeys: Make mprotect_key() mask off additional vm_flags
mm: Implement new pkey_mprotect() system call
x86/pkeys: Add fault handling for PF_PK page fault bit
Architecturally we need to keep __gp below 0x1000000.
But because of ftrace and tracepoint support, the RO_DATA_SECTION now gets much
bigger than it was before. By moving the linkage tables before RO_DATA_SECTION
we can avoid that __gp gets positioned at a too high address.
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Helge Deller <deller@gmx.de>
Increase the initial kernel default page mapping size for 64-bit kernels to
64 MB and for 32-bit kernels to 32 MB.
Due to the additional support of ftrace, tracepoint and huge pages the kernel
size can exceed the sizes we used up to now.
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Helge Deller <deller@gmx.de>
This file was only including module.h for exception table related
functions. We've now separated that content out into its own file
"extable.h" so now move over to that and avoid all the extra header
content in module.h that we don't really need to compile this file.
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Merge updates from Andrew Morton:
- fsnotify updates
- ocfs2 updates
- all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
console: don't prefer first registered if DT specifies stdout-path
cred: simpler, 1D supplementary groups
CREDITS: update Pavel's information, add GPG key, remove snail mail address
mailmap: add Johan Hovold
.gitattributes: set git diff driver for C source code files
uprobes: remove function declarations from arch/{mips,s390}
spelling.txt: "modeled" is spelt correctly
nmi_backtrace: generate one-line reports for idle cpus
arch/tile: adopt the new nmi_backtrace framework
nmi_backtrace: do a local dump_stack() instead of a self-NMI
nmi_backtrace: add more trigger_*_cpu_backtrace() methods
min/max: remove sparse warnings when they're nested
Documentation/filesystems/proc.txt: add more description for maps/smaps
mm, proc: fix region lost in /proc/self/smaps
proc: fix timerslack_ns CAP_SYS_NICE check when adjusting self
proc: add LSM hook checks to /proc/<tid>/timerslack_ns
proc: relax /proc/<tid>/timerslack_ns capability requirements
meminfo: break apart a very long seq_printf with #ifdefs
seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char
proc: faster /proc/*/status
...
Pull parisc updates from Helge Deller:
"Changes include:
- Fix boot of 32bit SMP kernel (initial kernel mapping was too small)
- Added hardened usercopy checks
- Drop bootmem and switch to memblock and NO_BOOTMEM implementation
- Drop the BROKEN_RODATA config option (and thus remove the relevant
code from the generic headers and files because parisc was the last
architecture which used this config option)
- Improve segfault reporting by printing human readable error strings
- Various smaller changes, e.g. dwarf debug support for assembly
code, update comments regarding copy_user_page_asm, switch to
kmalloc_array()"
* 'parisc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Increase KERNEL_INITIAL_SIZE for 32-bit SMP kernels
parisc: Drop bootmem and switch to memblock
parisc: Add hardened usercopy feature
parisc: Add cfi_startproc and cfi_endproc to assembly code
parisc: Move hpmc stack into page aligned bss section
parisc: Fix self-detected CPU stall warnings on Mako machines
parisc: Report trap type as human readable string
parisc: Update comment regarding implementation of copy_user_page_asm
parisc: Use kmalloc_array() in add_system_map_addresses()
parisc: Check return value of smp_boot_one_cpu()
parisc: Drop BROKEN_RODATA config option
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative. Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".
We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.
This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.
Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This came to light when implementing native 64-bit atomics for ARCv2.
The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
to check whether atomic64_dec_if_positive() is available. It seems it
was needed when not every arch defined it. However as of current code
the Kconfig option seems needless
- for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
generic definition of API is present lib/atomic64.c
- arches with native 64-bit atomics select it in arch/*/Kconfig and
define the API in their headers
So I see no point in keeping the Kconfig option
Compile tested for:
- blackfin (CONFIG_GENERIC_ATOMIC64)
- x86 (!CONFIG_GENERIC_ATOMIC64)
- ia64
Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ming Lin <ming.l@ssi.samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Increase the initial kernel default page mapping size for SMP kernels to 32MB
and add a runtime check which panics early if the kernel is bigger than the
initial mapping size.
This fixes boot crashes of 32bit SMP kernels. Due to the introduction of huge
page support in kernel 4.4 and it's required initial kernel layout in memory, a
32bit SMP kernel usually got bigger (in layout, not size) than 16MB.
Cc: stable@vger.kernel.org #4.4+
Signed-off-by: Helge Deller <deller@gmx.de>
Memblock is the standard kernel boot-time memory tracker/allocator. Use it
instead of the bootmem allocator. This allows using kmemleak, CMA and
other features.
Signed-off-by: Helge Deller <deller@gmx.de>
The config option HAVE_UNSTABLE_SCHED_CLOCK is set automatically when compiling
for SMP. There is no need to clear the stable-clock flag via
clear_sched_clock_stable() when starting secondary CPUs, and even worse,
clearing it triggers wrong self-detected CPU stall warnings on 64bit Mako
machines.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+
When faulting on some trap, the kernel currently reports in dmesg:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
vm_start = 0x00922000, vm_end = 0x00aed000
With this change the trap type additionally gets reported as human readable
string which makes it simpler to recognize the type of problem:
do_page_fault() command='perl' type=6 address=0xbe400403 in libcrypt-2.24.so[f9086000+9000]
trap #6: Instruction TLB miss fault, vm_start = 0x00922000, vm_end = 0x00aed000
Signed-off-by: Helge Deller <deller@gmx.de>
The attached patch describes the current implementation of
copy_user_page_asm(). It is possible to implement this routine using
either the kernel page mappings or equivalent aliases. I tested both
and decided the former was more efficient.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".
This issue was detected by using the Coccinelle software.
* Replace the specification of a data type by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Check return value of smp_boot_one_cpu() whether CPU could be brought up.
Reported-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
PARISC was the only architecture which selected the BROKEN_RODATA config
option. Drop it and remove the special handling from init.h as well.
Signed-off-by: Helge Deller <deller@gmx.de>
Pull uaccess fixes from Al Viro:
"Fixes for broken uaccess primitives - mostly lack of proper zeroing
in copy_from_user()/get_user()/__get_user(), but for several
architectures there's more (broken clear_user() on frv and
strncpy_from_user() on hexagon)"
* 'uaccess-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
avr32: fix copy_from_user()
microblaze: fix __get_user()
microblaze: fix copy_from_user()
m32r: fix __get_user()
blackfin: fix copy_from_user()
sparc32: fix copy_from_user()
sh: fix copy_from_user()
sh64: failing __get_user() should zero
score: fix copy_from_user() and friends
score: fix __get_user/get_user
s390: get_user() should zero on failure
ppc32: fix copy_from_user()
parisc: fix copy_from_user()
openrisc: fix copy_from_user()
nios2: fix __get_user()
nios2: copy_from_user() should zero the tail of destination
mn10300: copy_from_user() should zero on access_ok() failure...
mn10300: failing __get_user() and get_user() should zero
mips: copy_from_user() must zero the destination on access_ok() failure
ARC: uaccess: get_user to zero out dest in cause of fault
...
This patch adds two new system calls:
int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
int pkey_free(int pkey);
These implement an "allocator" for the protection keys
themselves, which can be thought of as analogous to the allocator
that the kernel has for file descriptors. The kernel tracks
which numbers are in use, and only allows operations on keys that
are valid. A key which was not obtained by pkey_alloc() may not,
for instance, be passed to pkey_mprotect().
These system calls are also very important given the kernel's use
of pkeys to implement execute-only support. These help ensure
that userspace can never assume that it has control of a key
unless it first asks the kernel. The kernel does not promise to
preserve PKRU (right register) contents except for allocated
pkeys.
The 'init_access_rights' argument to pkey_alloc() specifies the
rights that will be established for the returned pkey. For
instance:
pkey = pkey_alloc(flags, PKEY_DENY_WRITE);
will allocate 'pkey', but also sets the bits in PKRU[1] such that
writing to 'pkey' is already denied.
The kernel does not prevent pkey_free() from successfully freeing
in-use pkeys (those still assigned to a memory range by
pkey_mprotect()). It would be expensive to implement the checks
for this, so we instead say, "Just don't do it" since sane
software will never do it anyway.
Any piece of userspace calling pkey_alloc() needs to be prepared
for it to fail. Why? pkey_alloc() returns the same error code
(ENOSPC) when there are no pkeys and when pkeys are unsupported.
They can be unsupported for a whole host of reasons, so apps must
be prepared for this. Also, libraries or LD_PRELOADs might steal
keys before an application gets access to them.
This allocation mechanism could be implemented in userspace.
Even if we did it in userspace, we would still need additional
user/kernel interfaces to tell userspace which keys are being
used by the kernel internally (such as for execute-only
mappings). Having the kernel provide this facility completely
removes the need for these additional interfaces, or having an
implementation of this in userspace at all.
Note that we have to make changes to all of the architectures
that do not use mman-common.h because we use the new
PKEY_DENY_ACCESS/WRITE macros in arch-independent code.
1. PKRU is the Protection Key Rights User register. It is a
usermode-accessible register that controls whether writes
and/or access to each individual pkey is allowed or denied.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: linux-arch@vger.kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: arnd@arndb.de
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/20160729163015.444FE75F@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:
1) "copy_from_user() buffer size is too small" compile warning/error
This is a static warning which happens when object size and copy size
are both const, and copy size > object size. I didn't see any false
positives for this one. So the function warning attribute seems to
be working fine here.
Note this scenario is always a bug and so I think it should be
changed to *always* be an error, regardless of
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.
2) "copy_from_user() buffer size is not provably correct" compile warning
This is another static warning which happens when I enable
__compiletime_object_size() for new compilers (and
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size
is const, but copy size is *not*. In this case there's no way to
compare the two at build time, so it gives the warning. (Note the
warning is a byproduct of the fact that gcc has no way of knowing
whether the overflow function will be called, so the call isn't dead
code and the warning attribute is activated.)
So this warning seems to only indicate "this is an unusual pattern,
maybe you should check it out" rather than "this is a bug".
I get 102(!) of these warnings with allyesconfig and the
__compiletime_object_size() gcc check removed. I don't know if there
are any real bugs hiding in there, but from looking at a small
sample, I didn't see any. According to Kees, it does sometimes find
real bugs. But the false positive rate seems high.
3) "Buffer overflow detected" runtime warning
This is a runtime warning where object size is const, and copy size >
object size.
All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:
2fb0815c9e ("gcc4: disable __compiletime_object_size for GCC 4.6+")
That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size(). But in fact,
__compiletime_object_size() seems to be working fine. The false
positives were instead triggered by #2 above. (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)
So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.
Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.
Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Storing this value will help prevent unwinders from getting out of sync
with the function graph tracer ret_stack. Now instead of needing a
stateful iterator, they can compare the return address pointer to find
the right ret_stack entry.
Note that an array of 50 ftrace_ret_stack structs is allocated for every
task. So when an arch implements this, it will add either 200 or 400
bytes of memory usage per task (depending on whether it's a 32-bit or
64-bit platform).
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a95cfcc39e8f26b89a430c56926af0bb217bc0a1.1471607358.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When building gccgo in userspace, errno.h gets parsed and the go include file
sysinfo.go is generated.
Since EREFUSED is defined to the same value as ECONNREFUSED, and ECONNREFUSED
is defined later on in errno.h, this leads to go complaining that EREFUSED
isn't defined yet.
Fix this trivial problem by moving the define of EREFUSED down after
ECONNREFUSED in errno.h (and clean up the indenting while touching this line).
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Commit 54b6680090 (parisc: Add native high-resolution sched_clock()
implementation) added support to use the CPU-internal cr16 counters as reliable
clocksource with the help of HAVE_UNSTABLE_SCHED_CLOCK.
Sadly the commit missed to remove the hack which prevented cr16 to become the
default clocksource even on SMP systems.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.7+
Cleanups:
- huge cleanup of rtc-generic and char/genrtc this allowed to cleanup rtc-cmos,
rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc
- move mn10300 to rtc-cmos
Subsystem:
- fix wakealarms after hibernate
- multiples fixes for rctest
- simplify implementations of .read_alarm
New drivers:
- Maxim MAX6916
Drivers:
- ds1307: fix weekday
- m41t80: add wakeup support
- pcf85063: add support for PCF85063A variant
- rv8803: extend i2c fix and other fixes
- s35390a: fix alarm reading, this fixes instant reboot after shutdown for QNAP
TS-41x
- s3c: clock fixes
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Merge tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux
Pull RTC updates from Alexandre Belloni:
"RTC for 4.8
Cleanups:
- huge cleanup of rtc-generic and char/genrtc this allowed to cleanup
rtc-cmos, rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc
- move mn10300 to rtc-cmos
Subsystem:
- fix wakealarms after hibernate
- multiples fixes for rctest
- simplify implementations of .read_alarm
New drivers:
- Maxim MAX6916
Drivers:
- ds1307: fix weekday
- m41t80: add wakeup support
- pcf85063: add support for PCF85063A variant
- rv8803: extend i2c fix and other fixes
- s35390a: fix alarm reading, this fixes instant reboot after
shutdown for QNAP TS-41x
- s3c: clock fixes"
* tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (65 commits)
rtc: rv8803: Clear V1F when setting the time
rtc: rv8803: Stop the clock while setting the time
rtc: rv8803: Always apply the I²C workaround
rtc: rv8803: Fix read day of week
rtc: rv8803: Remove the check for valid time
rtc: rv8803: Kconfig: Indicate rx8900 support
rtc: asm9260: remove .owner field for driver
rtc: at91sam9: Fix missing spin_lock_init()
rtc: m41t80: add suspend handlers for alarm IRQ
rtc: m41t80: make it a real error message
rtc: pcf85063: Add support for the PCF85063A device
rtc: pcf85063: fix year range
rtc: hym8563: in .read_alarm set .tm_sec to 0 to signal minute accuracy
rtc: explicitly set tm_sec = 0 for drivers with minute accurancy
rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
rtc: s3c: Remove unnecessary call to disable already disabled clock
rtc: abx80x: use devm_add_action_or_reset()
rtc: m41t80: use devm_add_action_or_reset()
rtc: fix a typo and reduce three empty lines to one
rtc: s35390a: improve two comments in .set_alarm
...
Pull parisc updates from Helge Deller:
- added an optimized hash implementation for parisc (George Spelvin)
- C99 style cleanups in iomap.c (Amitoj Kaur Chawla)
- added breaks to switch statement in PDC function (noticed by Dan
Carpenter)
* 'parisc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Change structure intialisation to C99 style in iomap.c
parisc: Add break statements to pdc_pat_io_pci_cfg_read()
parisc: Add <asm/hash.h>
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer. Thus the pointer can point to const data.
However the attributes do not have to be a bitfield. Instead unsigned
long will do fine:
1. This is just simpler. Both in terms of reading the code and setting
attributes. Instead of initializing local attributes on the stack
and passing pointer to it to dma_set_attr(), just set the bits.
2. It brings safeness and checking for const correctness because the
attributes are passed by value.
Semantic patches for this change (at least most of them):
virtual patch
virtual context
@r@
identifier f, attrs;
@@
f(...,
- struct dma_attrs *attrs
+ unsigned long attrs
, ...)
{
...
}
@@
identifier r.f;
@@
f(...,
- NULL
+ 0
)
and
// Options: --all-includes
virtual patch
virtual context
@r@
identifier f, attrs;
type t;
@@
t f(..., struct dma_attrs *attrs);
@@
identifier r.f;
@@
f(...,
- NULL
+ 0
)
Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the in order struct initialisation style with explicit field
style.
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Dan Carpenter noticed that pdc_pat_io_pci_cfg_read() is problematic
because it's missing some break statements so it copies 4 bytes
regardless of whether you asked for only 1 or 2.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Helge Deller <deller@gmx.de>
PA-RISC is interesting; integer multiplies are implemented in the
FPU, so are painful in the kernel. But it tries to be friendly to
shift-and-add sequences for constant multiplies.
__hash_32 is implemented using the same shift-and-add sequence as
Microblaze, just scheduled for the PA7100. (It's 2-way superscalar
but in-order, like the Pentium.)
hash_64 was tricky, but a suggestion from Jason Thong allowed a
good solution by breaking up the multiplier. After a lot of manual
optimization, I found a 19-instruction sequence for the multiply that
can be executed in 10 cycles using only 4 temporaries.
(The PA8xxx can issue 4 instructions per cycle, but 2 must be ALU ops
and 2 must be loads/stores. And the final add can't be paired.)
An alternative considered, but ultimately not used, was Thomas Wang's
64-to-32-bit integer hash. At 12 instructions, it's smaller, but they're
all sequentially dependent, so it has longer latency.
https://web.archive.org/web/2011/http://www.concentric.net/~Ttwang/tech/inthash.htmhttp://burtleburtle.net/bob/hash/integer.html
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Pull security subsystem updates from James Morris:
"Highlights:
- TPM core and driver updates/fixes
- IPv6 security labeling (CALIPSO)
- Lots of Apparmor fixes
- Seccomp: remove 2-phase API, close hole where ptrace can change
syscall #"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (156 commits)
apparmor: fix SECURITY_APPARMOR_HASH_DEFAULT parameter handling
tpm: Add TPM 2.0 support to the Nuvoton i2c driver (NPCT6xx family)
tpm: Factor out common startup code
tpm: use devm_add_action_or_reset
tpm2_i2c_nuvoton: add irq validity check
tpm: read burstcount from TPM_STS in one 32-bit transaction
tpm: fix byte-order for the value read by tpm2_get_tpm_pt
tpm_tis_core: convert max timeouts from msec to jiffies
apparmor: fix arg_size computation for when setprocattr is null terminated
apparmor: fix oops, validate buffer size in apparmor_setprocattr()
apparmor: do not expose kernel stack
apparmor: fix module parameters can be changed after policy is locked
apparmor: fix oops in profile_unpack() when policy_db is not present
apparmor: don't check for vmalloc_addr if kvzalloc() failed
apparmor: add missing id bounds check on dfa verification
apparmor: allow SYS_CAP_RESOURCE to be sufficient to prlimit another task
apparmor: use list_next_entry instead of list_entry_next
apparmor: fix refcount race when finding a child profile
apparmor: fix ref count leak when profile sha1 hash is read
apparmor: check that xindex is in trans_table bounds
...
- LED driver for TI LP3952 6-Channel Color LED
LED core improvements:
- Only descend into leds directory when CONFIG_NEW_LEDS is set
- Add no-op gpio_led_register_device when LED subsystem is disabled
- MAINTAINERS: Add file patterns for led device tree bindings
LED Trigger core improvements:
- return error if invalid trigger name is provided via sysfs
LED class drivers improvements
- is31fl32xx: define complete i2c_device_id table
- is31fl32xx: fix typo in id and match table names
- leds-gpio: Set of_node for created LED devices
- pca9532: Add device tree support
Conversion of IDE trigger to common disk trigger:
- leds: convert IDE trigger to common disk trigger
- leds: documentation: 'ide-disk' to 'disk-activity'
- unicore32: use the new LED disk activity trigger
- parisc: use the new LED disk activity trigger
- mips: use the new LED disk activity trigger
- arm: use the new LED disk activity trigger
- powerpc: use the new LED disk activity trigger
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Merge tag 'leds_for_4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
Pull LED updates from Jacek Anaszewski:
"New LED class driver:
- LED driver for TI LP3952 6-Channel Color LED
LED core improvements:
- Only descend into leds directory when CONFIG_NEW_LEDS is set
- Add no-op gpio_led_register_device when LED subsystem is disabled
- MAINTAINERS: Add file patterns for led device tree bindings
LED Trigger core improvements:
- return error if invalid trigger name is provided via sysfs
LED class drivers improvements
- is31fl32xx: define complete i2c_device_id table
- is31fl32xx: fix typo in id and match table names
- leds-gpio: Set of_node for created LED devices
- pca9532: Add device tree support
Conversion of IDE trigger to common disk trigger:
- leds: convert IDE trigger to common disk trigger
- leds: documentation: 'ide-disk' to 'disk-activity'
- unicore32: use the new LED disk activity trigger
- parisc: use the new LED disk activity trigger
- mips: use the new LED disk activity trigger
- arm: use the new LED disk activity trigger
- powerpc: use the new LED disk activity trigger"
* tag 'leds_for_4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
leds: is31fl32xx: define complete i2c_device_id table
leds: is31fl32xx: fix typo in id and match table names
leds: LED driver for TI LP3952 6-Channel Color LED
leds: leds-gpio: Set of_node for created LED devices
leds: triggers: return error if invalid trigger name is provided via sysfs
leds: Only descend into leds directory when CONFIG_NEW_LEDS is set
leds: Add no-op gpio_led_register_device when LED subsystem is disabled
unicore32: use the new LED disk activity trigger
parisc: use the new LED disk activity trigger
mips: use the new LED disk activity trigger
arm: use the new LED disk activity trigger
powerpc: use the new LED disk activity trigger
leds: documentation: 'ide-disk' to 'disk-activity'
leds: convert IDE trigger to common disk trigger
leds: pca9532: Add device tree support
MAINTAINERS: Add file patterns for led device tree bindings
Pull locking updates from Ingo Molnar:
"The locking tree was busier in this cycle than the usual pattern - a
couple of major projects happened to coincide.
The main changes are:
- implement the atomic_fetch_{add,sub,and,or,xor}() API natively
across all SMP architectures (Peter Zijlstra)
- add atomic_fetch_{inc/dec}() as well, using the generic primitives
(Davidlohr Bueso)
- optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
Waiman Long)
- optimize smp_cond_load_acquire() on arm64 and implement LSE based
atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
on arm64 (Will Deacon)
- introduce smp_acquire__after_ctrl_dep() and fix various barrier
mis-uses and bugs (Peter Zijlstra)
- after discovering ancient spin_unlock_wait() barrier bugs in its
implementation and usage, strengthen its semantics and update/fix
usage sites (Peter Zijlstra)
- optimize mutex_trylock() fastpath (Peter Zijlstra)
- ... misc fixes and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
locking/static_keys: Fix non static symbol Sparse warning
locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
locking/atomic, arch/tile: Fix tilepro build
locking/atomic, arch/m68k: Remove comment
locking/atomic, arch/arc: Fix build
locking/Documentation: Clarify limited control-dependency scope
locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
locking/atomic, arch/mips: Convert to _relaxed atomics
locking/atomic, arch/alpha: Convert to _relaxed atomics
locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
locking/atomic: Fix atomic64_relaxed() bits
locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
...
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
pmd_alloc_one allocate PMD_ORDER which is 1. This means that this flag
has never been actually useful here because it has always been used only
for PAGE_ALLOC_COSTLY requests.
Link: http://lkml.kernel.org/r/1464599699-30131-10-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the third version of the patchset previously sent [1]. I have
basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get
rid of superfluous gfp flags" which went through dm tree. I am sending
it now because it is tree wide and chances for conflicts are reduced
considerably when we want to target rc2. I plan to send the next step
and rename the flag and move to a better semantic later during this
release cycle so we will have a new semantic ready for 4.8 merge window
hopefully.
Motivation:
While working on something unrelated I've checked the current usage of
__GFP_REPEAT in the tree. It seems that a majority of the usage is and
always has been bogus because __GFP_REPEAT has always been about costly
high order allocations while we are using it for order-0 or very small
orders very often. It seems that a big pile of them is just a
copy&paste when a code has been adopted from one arch to another.
I think it makes some sense to get rid of them because they are just
making the semantic more unclear. Please note that GFP_REPEAT is
documented as
* __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
* _might_ fail. This depends upon the particular VM implementation.
while !costly requests have basically nofail semantic. So one could
reasonably expect that order-0 request with __GFP_REPEAT will not loop
for ever. This is not implemented right now though.
I would like to move on with __GFP_REPEAT and define a better semantic
for it.
$ git grep __GFP_REPEAT origin/master | wc -l
111
$ git grep __GFP_REPEAT | wc -l
36
So we are down to the third after this patch series. The remaining
places really seem to be relying on __GFP_REPEAT due to large allocation
requests. This still needs some double checking which I will do later
after all the simple ones are sorted out.
I am touching a lot of arch specific code here and I hope I got it right
but as a matter of fact I even didn't compile test for some archs as I
do not have cross compiler for them. Patches should be quite trivial to
review for stupid compile mistakes though. The tricky parts are usually
hidden by macro definitions and thats where I would appreciate help from
arch maintainers.
[1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org
This patch (of 19):
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations. Yet we
have the full kernel tree with its usage for apparently order-0
allocations. This is really confusing because __GFP_REPEAT is
explicitly documented to allow allocation failures which is a weaker
semantic than the current order-0 has (basically nofail).
Let's simply drop __GFP_REPEAT from those places. This would allow to
identify place which really need allocator to retry harder and formulate
a more specific semantic for what the flag is supposed to do actually.
Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: John Crispin <blogic@openwrt.org>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since all architectures have this implemented now natively, remove this
dead code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.
This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Close the hole where ptrace can change a syscall out from under seccomp.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Currently, if arch code wants to supply seccomp_data directly to
seccomp (which is generally much faster than having seccomp do it
using the syscall_get_xyz() API), it has to use the two-phase
seccomp hooks. Add it to the easy hooks, too.
Cc: linux-arch@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
This patch updates/fixes all spin_unlock_wait() implementations.
The update is in semantics; where it previously was only a control
dependency, we now upgrade to a full load-acquire to match the
store-release from the spin_unlock() we waited on. This ensures that
when spin_unlock_wait() returns, we're guaranteed to observe the full
critical section we waited on.
This fixes a number of spin_unlock_wait() users that (not
unreasonably) rely on this.
I also fixed a number of ticket lock versions to only wait on the
current lock holder, instead of for a full unlock, as this is
sufficient.
Furthermore; again for ticket locks; I added an smp_rmb() in between
the initial ticket load and the spin loop testing the current value
because I could not convince myself the address dependency is
sufficient, esp. if the loads are of different sizes.
I'm more than happy to remove this smp_rmb() again if people are
certain the address dependency does indeed work as expected.
Note: PPC32 will be fixed independently
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: chris@zankel.net
Cc: cmetcalf@mellanox.com
Cc: davem@davemloft.net
Cc: dhowells@redhat.com
Cc: james.hogan@imgtec.com
Cc: jejb@parisc-linux.org
Cc: linux@armlinux.org.uk
Cc: mpe@ellerman.id.au
Cc: ralf@linux-mips.org
Cc: realmz6@gmail.com
Cc: rkuo@codeaurora.org
Cc: rth@twiddle.net
Cc: schwidefsky@de.ibm.com
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Cc: ysato@users.sourceforge.jp
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
One of the debian buildd servers had this crash in the syslog without
any other information:
Unaligned handler failed, ret = -2
clock_adjtime (pid 22578): Unaligned data reference (code 28)
CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G E 4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000
YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001001111100000001111 Tainted: G E
r00-03 000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
r04-07 00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
r08-11 0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
r12-15 000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
r16-19 0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
r20-23 0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
r24-27 0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
r28-31 0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
sr00-03 0000000001200000 0000000001200000 0000000000000000 0000000001200000
sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
IIR: 0ca0d089 ISR: 0000000001200000 IOR: 00000000fa6f7fff
CPU: 1 CR30: 00000001bde7c000 CR31: ffffffffffffffff
ORIG_R28: 00000002369fe628
IAOQ[0]: compat_get_timex+0x2dc/0x3c0
IAOQ[1]: compat_get_timex+0x2e0/0x3c0
RP(r2): compat_get_timex+0x40/0x3c0
Backtrace:
[<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
[<0000000040205024>] syscall_exit+0x0/0x14
This means the userspace program clock_adjtime called the clock_adjtime()
syscall and then crashed inside the compat_get_timex() function.
Syscalls should never crash programs, but instead return EFAULT.
The IIR register contains the executed instruction, which disassebles
into "ldw 0(sr3,r5),r9".
This load-word instruction is part of __get_user() which tried to read the word
at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in. The
unaligned handler is able to emulate all ldw instructions, but it fails if it
fails to read the source e.g. because of page fault.
The following program reproduces the problem:
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/mman.h>
int main(void) {
/* allocate 8k */
char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
/* free second half (upper 4k) and make it invalid. */
munmap(ptr+4096, 4096);
/* syscall where first int is unaligned and clobbers into invalid memory region */
/* syscall should return EFAULT */
return syscall(__NR_clock_adjtime, 0, ptr+4095);
}
To fix this issue we simply need to check if the faulting instruction address
is in the exception fixup table when the unaligned handler failed. If it
is, call the fixup routine instead of crashing.
While looking at the unaligned handler I found another issue as well: The
target register should not be modified if the handler was unsuccessful.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
This patch fixes backtrace on PA-RISC
There were several problems:
1) The code that decodes instructions handles instructions that subtract
from the stack pointer incorrectly. If the instruction subtracts the
number X from the stack pointer the code increases the frame size by
(0x100000000-X). This results in invalid accesses to memory and
recursive page faults.
2) Because gcc reorders blocks, handling instructions that subtract from
the frame pointer is incorrect. For example, this function
int f(int a)
{
if (__builtin_expect(a, 1))
return a;
g();
return a;
}
is compiled in such a way, that the code that decreases the stack
pointer for the first "return a" is placed before the code for "g" call.
If we recognize this decrement, we mistakenly believe that the frame
size for the "g" call is zero.
To fix problems 1) and 2), the patch doesn't recognize instructions that
decrease the stack pointer at all. To further safeguard the unwind code
against nonsense values, we don't allow frame size larger than
Total_frame_size.
3) The backtrace is not locked. If stack dump races with module unload,
invalid table can be accessed.
This patch adds a spinlock when processing module tables.
Note, that for correct backtrace, you need recent binutils.
Binutils 2.18 from Debian 5 produce garbage unwind tables.
Binutils 2.21 work better (it sometimes forgets function frames, but at
least it doesn't generate garbage).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
This architecture selects RTC_CLASS unconditionally, so the GEN_RTC
has not worked here for a long time.
Now we can remove both the asm/rtc.h header and the Kconfig dependency
for CONFIG_GEN_RTC.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The rtc-generic driver provides an architecture specific
wrapper on top of the generic rtc_class_ops abstraction,
and on pa-risc, that is implemented using an open-coded
version of rtc_time_to_tm/rtc_tm_to_time.
This changes the parisc rtc-generic device to provide its
rtc_class_ops directly, using the normal helper functions,
which makes this y2038 safe (on 32-bit) and simplifies
the implementation.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Nothing on these architectures ever includes the asm/mc146818rtc.h
file, the drivers that used to do this have been fixed long ago,
and the remaining users are all PC-specific.
This removes the files for good.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Depending on config options we will need to use a long jump to reach
ftrace_return_to_handler(). Additionally only compile the
parisc_return_to_handler code when CONFIG_FUNCTION_GRAPH_TRACER is set.
Signed-off-by: Helge Deller <deller@gmx.de>
The attached patch updates the parisc version of futex.h to match the
current generic implementation except for the spinlock code.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
When enabling all-branch ftrace support (CONFIG_PROFILE_ALL_BRANCHES)
the kernel gets really huge and some ftrace assembler functions like
mcount can't reach the ftrace helper functions which are written in C.
Avoid this problem of too distant branches by moving the ftrace C-helper
functions into the .text.hot section which is put in front of the
standard .text section by the linker.
Signed-off-by: Helge Deller <deller@gmx.de>
Add a native implementation for the sched_clock() function which utilizes the
processor-internal cycle counter (Control Register 16) as high-resolution time
source.
With this patch we now get much more fine-grained resolutions in various
in-kernel time measurements (e.g. when viewing the function tracing logs), and
probably a more accurate scheduling on SMP systems.
There are a few specific implementation details in this patch:
1. On a 32bit kernel we emulate the higher 32bits of the required 64-bit
resolution of sched_clock() by increasing a per-cpu counter at every
wrap-around of the 32bit cycle counter.
2. In a SMP system, the cycle counters of the various CPUs are not syncronized
(similiar to the TSC in a x86_64 system). To cope with this we define
HAVE_UNSTABLE_SCHED_CLOCK and let the upper layers do the adjustment work.
3. Since we need HAVE_UNSTABLE_SCHED_CLOCK, we need to provide a cmpxchg64()
function even on a 32-bit kernel.
4. A 64-bit SMP kernel which is started on a UP system will mark the
sched_clock() implementation as "stable", which means that we don't expect any
jumps in the returned counter. This is true because we then run only on one
CPU.
Signed-off-by: Helge Deller <deller@gmx.de>
By adding TRACEHOOK support we now get a clean user interface to access
registers via PTRACE_GETREGS, PTRACE_SETREGS, PTRACE_GETFPREGS and
PTRACE_SETFPREGS.
The user-visible regset struct user_regs_struct and user_fp_struct are
modelled similiar to x86 and can be accessed via PTRACE_GETREGSET.
Signed-off-by: Helge Deller <deller@gmx.de>
This patch simplifies the code for get_user() and put_user() a lot.
Instead of accessing kernel memory (%sr0) and userspace memory (%sr3)
hard-coded in the assembler instruction, we now preload %sr2 with either
%sr0 (for accessing KERNEL_DS) or with sr3 (to access USER_DS) and
use %sr2 in the load directly.
The generated code avoids a branch and speeds up execution by generating
less assembler instructions.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
This patch adds support for the TIF_SYSCALL_TRACEPOINT on the parisc
architecture. Basically, it calls the appropriate tracepoints on syscall
entry and exit.
Signed-off-by: Helge Deller <deller@gmx.de>
The binary GCD algorithm is based on the following facts:
1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)
Even on x86 machines with reasonable division hardware, the binary
algorithm runs about 25% faster (80% the execution time) than the
division-based Euclidian algorithm.
On platforms like Alpha and ARMv6 where division is a function call to
emulation code, it's even more significant.
There are two variants of the code here, depending on whether a fast
__ffs (find least significant set bit) instruction is available. This
allows the unpredictable branches in the bit-at-a-time shifting loop to
be eliminated.
If fast __ffs is not available, the "even/odd" GCD variant is used.
I use the following code to benchmark:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#define swap(a, b) \
do { \
a ^= b; \
b ^= a; \
a ^= b; \
} while (0)
unsigned long gcd0(unsigned long a, unsigned long b)
{
unsigned long r;
if (a < b) {
swap(a, b);
}
if (b == 0)
return a;
while ((r = a % b) != 0) {
a = b;
b = r;
}
return b;
}
unsigned long gcd1(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
b >>= __builtin_ctzl(b);
for (;;) {
a >>= __builtin_ctzl(a);
if (a == b)
return a << __builtin_ctzl(r);
if (a < b)
swap(a, b);
a -= b;
}
}
unsigned long gcd2(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
r &= -r;
while (!(b & r))
b >>= 1;
for (;;) {
while (!(a & r))
a >>= 1;
if (a == b)
return a;
if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}
unsigned long gcd3(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
b >>= __builtin_ctzl(b);
if (b == 1)
return r & -r;
for (;;) {
a >>= __builtin_ctzl(a);
if (a == 1)
return r & -r;
if (a == b)
return a << __builtin_ctzl(r);
if (a < b)
swap(a, b);
a -= b;
}
}
unsigned long gcd4(unsigned long a, unsigned long b)
{
unsigned long r = a | b;
if (!a || !b)
return r;
r &= -r;
while (!(b & r))
b >>= 1;
if (b == r)
return r;
for (;;) {
while (!(a & r))
a >>= 1;
if (a == r)
return r;
if (a == b)
return a;
if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}
static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
gcd0, gcd1, gcd2, gcd3, gcd4,
};
#define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))
#if defined(__x86_64__)
#define rdtscll(val) do { \
unsigned long __a,__d; \
__asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
(val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \
} while(0)
static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
unsigned long a, unsigned long b, unsigned long *res)
{
unsigned long long start, end;
unsigned long long ret;
unsigned long gcd_res;
rdtscll(start);
gcd_res = gcd(a, b);
rdtscll(end);
if (end >= start)
ret = end - start;
else
ret = ~0ULL - start + 1 + end;
*res = gcd_res;
return ret;
}
#else
static inline struct timespec read_time(void)
{
struct timespec time;
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
return time;
}
static inline unsigned long long diff_time(struct timespec start, struct timespec end)
{
struct timespec temp;
if ((end.tv_nsec - start.tv_nsec) < 0) {
temp.tv_sec = end.tv_sec - start.tv_sec - 1;
temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
} else {
temp.tv_sec = end.tv_sec - start.tv_sec;
temp.tv_nsec = end.tv_nsec - start.tv_nsec;
}
return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
}
static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
unsigned long a, unsigned long b, unsigned long *res)
{
struct timespec start, end;
unsigned long gcd_res;
start = read_time();
gcd_res = gcd(a, b);
end = read_time();
*res = gcd_res;
return diff_time(start, end);
}
#endif
static inline unsigned long get_rand()
{
if (sizeof(long) == 8)
return (unsigned long)rand() << 32 | rand();
else
return rand();
}
int main(int argc, char **argv)
{
unsigned int seed = time(0);
int loops = 100;
int repeats = 1000;
unsigned long (*res)[TEST_ENTRIES];
unsigned long long elapsed[TEST_ENTRIES];
int i, j, k;
for (;;) {
int opt = getopt(argc, argv, "n:r:s:");
/* End condition always first */
if (opt == -1)
break;
switch (opt) {
case 'n':
loops = atoi(optarg);
break;
case 'r':
repeats = atoi(optarg);
break;
case 's':
seed = strtoul(optarg, NULL, 10);
break;
default:
/* You won't actually get here. */
break;
}
}
res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
memset(elapsed, 0, sizeof(elapsed));
srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
/* Do we have args? */
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
unsigned long long min_elapsed[TEST_ENTRIES];
for (k = 0; k < repeats; k++) {
for (i = 0; i < TEST_ENTRIES; i++) {
unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
if (k == 0 || min_elapsed[i] > tmp)
min_elapsed[i] = tmp;
}
}
for (i = 0; i < TEST_ENTRIES; i++)
elapsed[i] += min_elapsed[i];
}
for (i = 0; i < TEST_ENTRIES; i++)
printf("gcd%d: elapsed %llu\n", i, elapsed[i]);
k = 0;
srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
for (i = 1; i < TEST_ENTRIES; i++) {
if (res[j][i] != res[j][0])
break;
}
if (i < TEST_ENTRIES) {
if (k == 0) {
k = 1;
fprintf(stderr, "Error:\n");
}
fprintf(stderr, "gcd(%lu, %lu): ", a, b);
for (i = 0; i < TEST_ENTRIES; i++)
fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
}
}
if (k == 0)
fprintf(stderr, "PASS\n");
free(res);
return 0;
}
Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 10174
gcd1: elapsed 2120
gcd2: elapsed 2902
gcd3: elapsed 2039
gcd4: elapsed 2812
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9309
gcd1: elapsed 2280
gcd2: elapsed 2822
gcd3: elapsed 2217
gcd4: elapsed 2710
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9589
gcd1: elapsed 2098
gcd2: elapsed 2815
gcd3: elapsed 2030
gcd4: elapsed 2718
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9914
gcd1: elapsed 2309
gcd2: elapsed 2779
gcd3: elapsed 2228
gcd4: elapsed 2709
PASS
[akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Define HAVE_EXIT_THREAD for archs which want to do something in
exit_thread. For others, let's define exit_thread as an empty inline.
This is a cleanup before we change the prototype of exit_thread to
accept a task parameter.
[akpm@linux-foundation.org: fix mips]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Do not load one entry beyond the end of the syscall table when the
syscall number of a traced process equals to __NR_Linux_syscalls.
Similar bug with regular processes was fixed by commit 3bb457af4f
("[PARISC] Fix bug when syscall nr is __NR_Linux_syscalls").
This bug was found by strace test suite.
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Pull parisc ftrace fixes from Helge Deller:
"This is (most likely) the last pull request for v4.6 for the parisc
architecture.
It fixes the FTRACE feature for parisc, which is horribly broken since
quite some time and doesn't even compile. This patch just fixes the
bare minimum (it actually removes more lines than it adds), so that
the function tracer works again on 32- and 64bit kernels.
I've queued up additional patches on top of this patch which e.g. add
the syscall tracer, but those have to wait for the merge window for
v4.7."
* 'parisc-4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix ftrace function tracer
Fix the FTRACE function tracer for 32- and 64-bit kernel.
The former code was horribly broken.
Reimplement most coding in assembly and utilize optimizations, e.g. put
mcount() and ftrace_stub() into one L1 cacheline.
Signed-off-by: Helge Deller <deller@gmx.de>
Update the comment to reflect the changes of commit 0de7985 (parisc: Use
generic extable search and sort routines).
Signed-off-by: Helge Deller <deller@gmx.de>
Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.
When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Ingo Molnar