- 11 Sep, 2010 6 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds authored
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: sparc: Kill all BKL usage.
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Linus Torvalds authored
Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, tsc: Fix a preemption leak in restore_sched_clock_state() sched: Move sched_avg_update() to update_cpu_load()
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Peter Zijlstra authored
Doh, a real life genuine preemption leak.. This caused a suspend failure. Reported-bisected-and-tested-by-the-invaluable: Jeff Chua <jeff.chua.linux@gmail.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Nico Schottelius <nico-linux-20100709@schottelius.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Florian Pritz <flo@xssn.at> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: <stable@kernel.org> # Greg, please apply after: cd7240c0 ("x86, tsc, sched: Recompute cyc2ns_offset's during resume from") sleep states LKML-Reference: <1284150773.402.122.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intelLinus Torvalds authored
* 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel: drm/i915: don't enable self-refresh on Ironlake drm/i915: Double check that the wait_request is not pending before warning Revert "drm/i915: Warn if we run out of FIFO space for a mode" Revert "drm/i915: Allow LVDS on pipe A on gen4+" Revert "drm/i915: Enable RC6 on Ironlake."
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git://oss.sgi.com/xfs/xfsLinus Torvalds authored
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: log IO completion workqueue is a high priority queue xfs: prevent reading uninitialized stack memory
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Peter Zijlstra authored
A real life genuine preemption leak.. Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 10 Sep, 2010 34 commits
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Dave Chinner authored
The workqueue implementation in 2.6.36-rcX has changed, resulting in the workqueues no longer having dedicated threads for work processing. This has caused severe livelocks under heavy parallel create workloads because the log IO completions have been getting held up behind metadata IO completions. Hence log commits would stall, memory allocation would stall because pages could not be cleaned, and lock contention on the AIL during inode IO completion processing was being seen to slow everything down even further. By making the log Io completion workqueue a high priority workqueue, they are queued ahead of all data/metadata IO completions and processed before the data/metadata completions. Hence the log never gets stalled, and operations needed to clean memory can continue as quickly as possible. This avoids the livelock conditions and allos the system to keep running under heavy load as per normal. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
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Roland McGrath authored
An execve with a very large total of argument/environment strings can take a really long time in the execve system call. It runs uninterruptibly to count and copy all the strings. This change makes it abort the exec quickly if sent a SIGKILL. Note that this is the conservative change, to interrupt only for SIGKILL, by using fatal_signal_pending(). It would be perfectly correct semantics to let any signal interrupt the string-copying in execve, i.e. use signal_pending() instead of fatal_signal_pending(). We'll save that change for later, since it could have user-visible consequences, such as having a timer set too quickly make it so that an execve can never complete, though it always happened to work before. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roland McGrath authored
This adds a preemption point during the copying of the argument and environment strings for execve, in copy_strings(). There is already a preemption point in the count() loop, so this doesn't add any new points in the abstract sense. When the total argument+environment strings are very large, the time spent copying them can be much more than a normal user time slice. So this change improves the interactivity of the rest of the system when one process is doing an execve with very large arguments. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roland McGrath authored
The CONFIG_STACK_GROWSDOWN variant of setup_arg_pages() does not check the size of the argument/environment area on the stack. When it is unworkably large, shift_arg_pages() hits its BUG_ON. This is exploitable with a very large RLIMIT_STACK limit, to create a crash pretty easily. Check that the initial stack is not too large to make it possible to map in any executable. We're not checking that the actual executable (or intepreter, for binfmt_elf) will fit. So those mappings might clobber part of the initial stack mapping. But that is just userland lossage that userland made happen, not a kernel problem. Signed-off-by: Roland McGrath <roland@redhat.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Perform hardware_enable in CPU_STARTING callback KVM: i8259: fix migration KVM: fix i8259 oops when no vcpus are online KVM: x86 emulator: fix regression with cmpxchg8b on i386 hosts
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Linus Torvalds authored
Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: t_start: reset FTRACE_ITER_HASH in case of seek/pread perf symbols: Fix multiple initialization of symbol system perf: Fix CPU hotplug perf, trace: Fix module leak tracing/kprobe: Fix handling of C-unlike argument names tracing/kprobes: Fix handling of argument names perf probe: Fix handling of arguments names perf probe: Fix return probe support tracing/kprobe: Fix a memory leak in error case tracing: Do not allow llseek to set_ftrace_filter
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David Howells authored
Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership of the parent process's session keyring whether or not the parent has a session keyring [CVE-2010-2960]. This results in the following oops: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0 IP: [<ffffffff811ae4dd>] keyctl_session_to_parent+0x251/0x443 ... Call Trace: [<ffffffff811ae2f3>] ? keyctl_session_to_parent+0x67/0x443 [<ffffffff8109d286>] ? __do_fault+0x24b/0x3d0 [<ffffffff811af98c>] sys_keyctl+0xb4/0xb8 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b if the parent process has no session keyring. If the system is using pam_keyinit then it mostly protected against this as all processes derived from a login will have inherited the session keyring created by pam_keyinit during the log in procedure. To test this, pam_keyinit calls need to be commented out in /etc/pam.d/. Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Tavis Ormandy <taviso@cmpxchg8b.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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David Howells authored
There's an protected access to the parent process's credentials in the middle of keyctl_session_to_parent(). This results in the following RCU warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/keys/keyctl.c:1291 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by keyctl-session-/2137: #0: (tasklist_lock){.+.+..}, at: [<ffffffff811ae2ec>] keyctl_session_to_parent+0x60/0x236 stack backtrace: Pid: 2137, comm: keyctl-session- Not tainted 2.6.36-rc2-cachefs+ #1 Call Trace: [<ffffffff8105606a>] lockdep_rcu_dereference+0xaa/0xb3 [<ffffffff811ae379>] keyctl_session_to_parent+0xed/0x236 [<ffffffff811af77e>] sys_keyctl+0xb4/0xb6 [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b The code should take the RCU read lock to make sure the parents credentials don't go away, even though it's holding a spinlock and has IRQ disabled. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.dk/linux-2.6-blockLinus Torvalds authored
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: block: Range check cpu in blk_cpu_to_group scatterlist: prevent invalid free when alloc fails writeback: Fix lost wake-up shutting down writeback thread writeback: do not lose wakeup events when forking bdi threads cciss: fix reporting of max queue depth since init block: switch s390 tape_block and mg_disk to elevator_change() block: add function call to switch the IO scheduler from a driver fs/bio-integrity.c: return -ENOMEM on kmalloc failure bio-integrity.c: remove dependency on __GFP_NOFAIL BLOCK: fix bio.bi_rw handling block: put dev->kobj in blk_register_queue fail path cciss: handle allocation failure cfq-iosched: Documentation help for new tunables cfq-iosched: blktrace print per slice sector stats cfq-iosched: Implement tunable group_idle cfq-iosched: Do group share accounting in IOPS when slice_idle=0 cfq-iosched: Do not idle if slice_idle=0 cciss: disable doorbell reset on reset_devices blkio: Fix return code for mkdir calls
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git://github.com/at91linux/linux-2.6-at91Linus Torvalds authored
* 'at91-fixes-for-linus' of git://github.com/at91linux/linux-2.6-at91: AT91: at91sam9261ek: remove C99 comments but keep information AT91: at91sam9261ek board: remove warnings related to use of SPI or SD/MMC AT91: dm9000 initialization update AT91: SAM9G45 - add a separate clock entry for every single TC block AT91: clock: peripheral clocks can have other parent than mck AT91: change dma resource index
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6Linus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: ALSA: rawmidi: fix the get next midi device ioctl ALSA: hda - Fix wrong HP pin detection in snd_hda_parse_pin_def_config() ALSA: seq/oss - Fix double-free at error path of snd_seq_oss_open() ALSA: msnd-classic: Fix invalid cfg parameter ALSA: hda - Enable PC-beep for EeePC with ALC269 codec ALSA: hda - Add errata initverb sequence for CS42xx codecs ALSA: usb - Release capture substream URBs properly ALSA: virtuoso: fix setting of Xonar DS line-in/mic-in controls ALSA: virtuoso: work around missing reset in the Xonar DS Windows driver ALSA: hda - Add quirk for Lenovo T400s ALSA: usb-audio: fix detection of vendor-specific device protocol settings ALSA: usb-audio: Assume first control interface is for audio ALSA: hda - Add a new hp-laptop model for Conexant 5066, tested on HP G60
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Jesse Barnes authored
We don't know how to enable it safely, especially as outputs turn on and off. When disabling LP1 we also need to make sure LP2 and 3 are already disabled. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29173 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29082Reported-by: Chris Lord <chris@linux.intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Tested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: stable@kernel.org Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
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Dan Rosenberg authored
The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12 bytes of uninitialized stack memory, because the fsxattr struct declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero) the 12-byte fsx_pad member before copying it back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
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Nicolas Ferre authored
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
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Nicolas Ferre authored
The sd/mmc data structure is not used if SPI is selected. The configuration of PIO on the board prevent from using both interfaces at the same time (board dependent). Remove the warnings at compilation time adding a preprocessor condition. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
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Nicolas Ferre authored
Add information in dm9000 mac/phy chip initialization: - irq resource details - platform data details Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
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Brian King authored
While testing CPU DLPAR, the following problem was discovered. We were DLPAR removing the first CPU, which in this case was logical CPUs 0-3. CPUs 0-2 were already marked offline and we were in the process of offlining CPU 3. After marking the CPU inactive and offline in cpu_disable, but before the cpu was completely idle (cpu_die), we ended up in __make_request on CPU 3. There we looked at the topology map to see which CPU to complete the I/O on and found no CPUs in the cpu_sibling_map. This resulted in the block layer setting the completion cpu to be NR_CPUS, which then caused an oops when we tried to complete the I/O. Fix this by sanity checking the value we return from blk_cpu_to_group to be a valid cpu value. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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Takashi Iwai authored
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Ingo Molnar authored
Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/urgent
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Ingo Molnar authored
Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/urgent
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git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-devLinus Torvalds authored
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev: libata-sff: Reenable Port Multiplier after libata-sff remodeling. libata: skip EH autopsy and recovery during suspend ahci: AHCI and RAID mode SATA patch for Intel Patsburg DeviceIDs ata_piix: IDE Mode SATA patch for Intel Patsburg DeviceIDs libata,pata_via: revert ata_wait_idle() removal from ata_sff/via_tf_load() ahci: fix hang on failed softreset pata_artop: Fix device ID parity check
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Chris Wright authored
Be sure to avoid entering t_show() with FTRACE_ITER_HASH set without having properly started the iterator to iterate the hash. This case is degenerate and, as discovered by Robert Swiecki, can cause t_hash_show() to misuse a pointer. This causes a NULL ptr deref with possible security implications. Tracked as CVE-2010-3079. Cc: Robert Swiecki <swiecki@google.com> Cc: Eugene Teo <eugene@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Gwendal Grignou authored
Keep track of the link on the which the current request is in progress. It allows support of links behind port multiplier. Not all libata-sff is PMP compliant. Code for native BMDMA controller does not take in accound PMP. Tested on Marvell 7042 and Sil7526. Signed-off-by: Gwendal Grignou <gwendal@google.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Tejun Heo authored
For some mysterious reason, certain hardware reacts badly to usual EH actions while the system is going for suspend. As the devices won't be needed until the system is resumed, ask EH to skip usual autopsy and recovery and proceed directly to suspend. Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Stephan Diestelhorst <stephan.diestelhorst@amd.com> Cc: stable@kernel.org Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Seth Heasley authored
This patch adds the Intel Patsburg (PCH) SATA AHCI and RAID Controller DeviceIDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Seth Heasley authored
This patch adds the Intel Patsburg (PCH) IDE mode SATA Controller DeviceIDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Tejun Heo authored
Commit 978c0666 (libata: Remove excess delay in the tf_load path) removed ata_wait_idle() from ata_sff_tf_load() and via_tf_load(). This caused obscure detection problems in sata_sil. https://bugzilla.kernel.org/show_bug.cgi?id=16606 The commit was pure performance optimization. Revert it for now. Reported-by: Dieter Plaetinck <dieter@plaetinck.be> Reported-by: Jan Beulich <JBeulich@novell.com> Bisected-by: gianluca <gianluca@sottospazio.it> Cc: stable@kernel.org Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Jorge Boncompte [DTI2] authored
Commit 9eed1fb7 ("minix: replace inode uid,gid,mode init with helper") broke directory creation on minix filesystems. Fix it by passing the needed mode flag to inode init helper. Signed-off-by: Jorge Boncompte [DTI2] <jorge@dti2.net> Cc: Dmitry Monakhov <dmonakhov@openvz.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@kernel.org> [2.6.35.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mel Gorman authored
When under significant memory pressure, a process enters direct reclaim and immediately afterwards tries to allocate a page. If it fails and no further progress is made, it's possible the system will go OOM. However, on systems with large amounts of memory, it's possible that a significant number of pages are on per-cpu lists and inaccessible to the calling process. This leads to a process entering direct reclaim more often than it should increasing the pressure on the system and compounding the problem. This patch notes that if direct reclaim is making progress but allocations are still failing that the system is already under heavy pressure. In this case, it drains the per-cpu lists and tries the allocation a second time before continuing. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Wu Fengguang <fengguang.wu@intel.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>
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Christoph Lameter authored
mm: page allocator: calculate a better estimate of NR_FREE_PAGES when memory is low and kswapd is awake Ordinarily watermark checks are based on the vmstat NR_FREE_PAGES as it is cheaper than scanning a number of lists. To avoid synchronization overhead, counter deltas are maintained on a per-cpu basis and drained both periodically and when the delta is above a threshold. On large CPU systems, the difference between the estimated and real value of NR_FREE_PAGES can be very high. If NR_FREE_PAGES is much higher than number of real free page in buddy, the VM can allocate pages below min watermark, at worst reducing the real number of pages to zero. Even if the OOM killer kills some victim for freeing memory, it may not free memory if the exit path requires a new page resulting in livelock. This patch introduces a zone_page_state_snapshot() function (courtesy of Christoph) that takes a slightly more accurate view of an arbitrary vmstat counter. It is used to read NR_FREE_PAGES while kswapd is awake to avoid the watermark being accidentally broken. The estimate is not perfect and may result in cache line bounces but is expected to be lighter than the IPI calls necessary to continually drain the per-cpu counters while kswapd is awake. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mel Gorman authored
When allocating a page, the system uses NR_FREE_PAGES counters to determine if watermarks would remain intact after the allocation was made. This check is made without interrupts disabled or the zone lock held and so is race-prone by nature. Unfortunately, when pages are being freed in batch, the counters are updated before the pages are added on the list. During this window, the counters are misleading as the pages do not exist yet. When under significant pressure on systems with large numbers of CPUs, it's possible for processes to make progress even though they should have been stalled. This is particularly problematic if a number of the processes are using GFP_ATOMIC as the min watermark can be accidentally breached and in extreme cases, the system can livelock. This patch updates the counters after the pages have been added to the list. This makes the allocator more cautious with respect to preserving the watermarks and mitigates livelock possibilities. [akpm@linux-foundation.org: avoid modifying incoming args] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> 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>
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KAMEZAWA Hiroyuki authored
refresh_zone_stat_thresholds() calculates parameter based on the number of online cpus. It's called at cpu offlining but needs to be called at onlining, too. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Acked-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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James Bottomley authored
O_NONBLOCK on parisc has a dual value: #define O_NONBLOCK 000200004 /* HPUX has separate NDELAY & NONBLOCK */ It is caught by the O_* bits uniqueness check and leads to a parisc compile error. The fix would be to take O_NONBLOCK out. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Cc: Jamie Lokier <jamie@shareable.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Tests with recent firmware on Intel X25-M 80GB and OCZ Vertex 60GB SSDs show a shift since I last tested in December: in part because of firmware updates, in part because of the necessary move from barriers to awaiting completion at the block layer. While discard at swapon still shows as slightly beneficial on both, discarding 1MB swap cluster when allocating is now disadvanteous: adds 25% overhead on Intel, adds 230% on OCZ (YMMV). Surrender: discard as presently implemented is more hindrance than help for swap; but might prove useful on other devices, or with improvements. So continue to do the discard at swapon, but make discard while swapping conditional on a SWAP_FLAG_DISCARD to sys_swapon() (which has been using only the lower 16 bits of int flags). We can add a --discard or -d to swapon(8), and a "discard" to swap in /etc/fstab: matching the mount option for btrfs, ext4, fat, gfs2, nilfs2. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Nigel Cunningham <nigel@tuxonice.net> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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