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2013-10-04sched/wait: Clean up wait.h details a bitIngo Molnar
Since we are changing wait.h profoundly, use the opportunity to: - add a sentence to explain what this file is about - remove whitespace noise - prettify weird looking line break fixup attempts - standardize type definition and initialization sequences - use consistent style details No code is changed. Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-O8dIie5swnctqpupakatvqyq@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Make the __wait_event*() interface more friendlyPeter Zijlstra
Change all __wait_event*() implementations to match the corresponding wait_event*() signature for convenience. In particular this does away with the weird 'ret' logic. Since there are __wait_event*() users this requires we update them too. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092529.042563462@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_hrtimeout()Peter Zijlstra
While not a whole-sale replacement like the others we can still reduce the size of __wait_event_hrtimeout() considerably by noting that the actual core of __wait_event_hrtimeout() is identical to what ___wait_event() generates. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.972793648@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_killable()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.898691966@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible_tty()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.831085521@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible_lock_irq_timeout()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.759956109@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible_lock_irq()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.686006009@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_lock_irq()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.612813379@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible_exclusive()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.541716442@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible_timeout()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.469616907@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_interruptible()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.396949919@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event_timeout()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.325264677@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Collapse __wait_event()Peter Zijlstra
Reduce macro complexity by using the new ___wait_event() helper. No change in behaviour, identical generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.254863348@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Introduce ___wait_event()Peter Zijlstra
There's far too much duplication in the __wait_event macros; in order to fix this introduce ___wait_event() a macro with the capability to replace most other macros. With the previous patches changing the various __wait_event*() implementations to be more uniform; we can now collapse the lot without also changing generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.181897111@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Change the wait_exclusive control flowPeter Zijlstra
Purely a preparatory patch; it changes the control flow to match what will soon be generated by generic code so that that patch can be a unity transform. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.107994763@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Change timeout logicPeter Zijlstra
Commit 4c663cf ("wait: fix false timeouts when using wait_event_timeout()") introduced an additional condition check after a timeout but there's a few issues; - it forgot one site - it put the check after the main loop; not at the actual timeout check. Cure both; by wrapping the condition (as suggested by Oleg), this avoids double evaluation of 'condition' which could be quite big. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.028892896@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04sched/wait: Make the signal_pending() checks consistentPeter Zijlstra
There's two patterns to check signals in the __wait_event*() macros: if (!signal_pending(current)) { schedule(); continue; } ret = -ERESTARTSYS; break; And the more natural: if (signal_pending(current)) { ret = -ERESTARTSYS; break; } schedule(); Change them all into the latter form. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092527.956416254@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-28sched: Revert need_resched() to look at TIF_NEED_RESCHEDPeter Zijlstra
Yuanhan reported a serious throughput regression in his pigz benchmark. Using the ftrace patch I found that several idle paths need more TLC before we can switch the generic need_resched() over to preempt_need_resched. The preemption paths benefit most from preempt_need_resched and do indeed use it; all other need_resched() users don't really care that much so reverting need_resched() back to tif_need_resched() is the simple and safe solution. Reported-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: lkp@linux.intel.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20130927153003.GF15690@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched, x86: Optimize the preempt_schedule() callPeter Zijlstra
Remove the bloat of the C calling convention out of the preempt_enable() sites by creating an ASM wrapper which allows us to do an asm("call ___preempt_schedule") instead. calling.h bits by Andi Kleen Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-tk7xdi1cvvxewixzke8t8le1@git.kernel.org [ Fixed build error. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched: Prepare for per-cpu preempt_countPeter Zijlstra
When using per-cpu preempt_count variables we need to save/restore the preempt_count on context switch (into per task storage; for instance the old thread_info::preempt_count variable) because of PREEMPT_ACTIVE. However, this means that on fork() the preempt_count value of the last context switch gets copied and if we had a PREEMPT_ACTIVE switch right before cloning a child task the child task will now too have PREEMPT_ACTIVE set and start its life with an extra PREEMPT_ACTIVE count. Therefore we need to make init_task_preempt_count() unconditional; this resets whatever preempt_count we inherited from our parent process. Doing so for !per-cpu implementations is harmless. For !PREEMPT_COUNT kernels we need to be careful not to start life with an increased preempt_count. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-4k0b7oy1rcdyzochwiixuwi9@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched: Extract the basic add/sub preempt_count modifiersPeter Zijlstra
Rewrite the preempt_count macros in order to extract the 3 basic preempt_count value modifiers: __preempt_count_add() __preempt_count_sub() and the new: __preempt_count_dec_and_test() And since we're at it anyway, replace the unconventional $op_preempt_count names with the more conventional preempt_count_$op. Since these basic operators are equivalent to the previous _notrace() variants, do away with the _notrace() versions. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-ewbpdbupy9xpsjhg960zwbv8@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched, arch: Create asm/preempt.hPeter Zijlstra
In order to prepare to per-arch implementations of preempt_count move the required bits into an asm-generic header and use this for all archs. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-h5j0c1r3e3fk015m30h8f1zx@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched: Add NEED_RESCHED to the preempt_countPeter Zijlstra
In order to combine the preemption and need_resched test we need to fold the need_resched information into the preempt_count value. Since the NEED_RESCHED flag is set across CPUs this needs to be an atomic operation, however we very much want to avoid making preempt_count atomic, therefore we keep the existing TIF_NEED_RESCHED infrastructure in place but at 3 sites test it and fold its value into preempt_count; namely: - resched_task() when setting TIF_NEED_RESCHED on the current task - scheduler_ipi() when resched_task() sets TIF_NEED_RESCHED on a remote task it follows it up with a reschedule IPI and we can modify the cpu local preempt_count from there. - cpu_idle_loop() for when resched_task() found tsk_is_polling(). We use an inverted bitmask to indicate need_resched so that a 0 means both need_resched and !atomic. Also remove the barrier() in preempt_enable() between preempt_enable_no_resched() and preempt_check_resched() to avoid having to reload the preemption value and allow the compiler to use the flags of the previuos decrement. I couldn't come up with any sane reason for this barrier() to be there as preempt_enable_no_resched() already has a barrier() before doing the decrement. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-7a7m5qqbn5pmwnd4wko9u6da@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched: Introduce preempt_count accessor functionsPeter Zijlstra
Replace the single preempt_count() 'function' that's an lvalue with two proper functions: preempt_count() - returns the preempt_count value as rvalue preempt_count_set() - Allows setting the preempt-count value Also provide preempt_count_ptr() as a convenience wrapper to implement all modifying operations. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-orxrbycjozopqfhb4dxdkdvb@git.kernel.org [ Fixed build failure. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched, idle: Fix the idle polling state logicPeter Zijlstra
Mike reported that commit 7d1a9417 ("x86: Use generic idle loop") regressed several workloads and caused excessive reschedule interrupts. The patch in question failed to notice that the x86 code had an inverted sense of the polling state versus the new generic code (x86: default polling, generic: default !polling). Fix the two prominent x86 mwait based idle drivers and introduce a few new generic polling helpers (fixing the wrong smp_mb__after_clear_bit usage). Also switch the idle routines to using tif_need_resched() which is an immediate TIF_NEED_RESCHED test as opposed to need_resched which will end up being slightly different. Reported-by: Mike Galbraith <bitbucket@online.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: lenb@kernel.org Cc: tglx@linutronix.de Link: http://lkml.kernel.org/n/tip-nc03imb0etuefmzybzj7sprf@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched: Remove {set,clear}_need_reschedPeter Zijlstra
Preemption semantics are going to change which mandate a change. All DRM usage sites are already broken and will not be affected (much) by this change. DRM people are aware and will remove the last few stragglers. For now, leave an empty stub that generates a warning, once all users are gone we can remove this. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: airlied@linux.ie Cc: daniel.vetter@ffwll.ch Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/n/tip-qfc1el2zvhxiyut4ai99ij4n@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20sched/balancing: Periodically decay max cost of idle balanceJason Low
This patch builds on patch 2 and periodically decays that max value to do idle balancing per sched domain by approximately 1% per second. Also decay the rq's max_idle_balance_cost value. Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1379096813-3032-4-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20sched/balancing: Consider max cost of idle balance per sched domainJason Low
In this patch, we keep track of the max cost we spend doing idle load balancing for each sched domain. If the avg time the CPU remains idle is less then the time we have already spent on idle balancing + the max cost of idle balancing in the sched domain, then we don't continue to attempt the balance. We also keep a per rq variable, max_idle_balance_cost, which keeps track of the max time spent on newidle load balances throughout all its domains so that we can determine the avg_idle's max value. By using the max, we avoid overrunning the average. This further reduces the chance we attempt balancing when the CPU is not idle for longer than the cost to balance. Signed-off-by: Jason Low <jason.low2@hp.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1379096813-3032-3-git-send-email-jason.low2@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-17Merge branch 'fixes' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Gleb Natapov. * 'fixes' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: VMX: set "blocked by NMI" flag if EPT violation happens during IRET from NMI kvm: free resources after canceling async_pf KVM: nEPT: reset PDPTR register cache on nested vmentry emulation KVM: mmu: allow page tables to be in read-only slots KVM: x86 emulator: emulate RETF imm
2013-09-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid Pull HID updates from Jiri Kosina: "Fixes for CVE-2013-2897, CVE-2013-2895, CVE-2013-2897, CVE-2013-2894, CVE-2013-2893, CVE-2013-2891, CVE-2013-2890, CVE-2013-2889. All the bugs are triggerable only by specially crafted evil-on-purpose HW devices. Fixes by Kees Cook and Benjamin Tissoires" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: HID: lenovo-tpkbd: fix leak if tpkbd_probe_tp fails HID: multitouch: validate indexes details HID: logitech-dj: validate output report details HID: validate feature and input report details HID: lenovo-tpkbd: validate output report details HID: LG: validate HID output report details HID: steelseries: validate output report details HID: sony: validate HID output report details HID: zeroplus: validate output report details HID: provide a helper for validating hid reports
2013-09-17KVM: mmu: allow page tables to be in read-only slotsPaolo Bonzini
Page tables in a read-only memory slot will currently cause a triple fault because the page walker uses gfn_to_hva and it fails on such a slot. OVMF uses such a page table; however, real hardware seems to be fine with that as long as the accessed/dirty bits are set. Save whether the slot is readonly, and later check it when updating the accessed and dirty bits. Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-16Merge branch 'timers/core' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer code update from Thomas Gleixner: - armada SoC clocksource overhaul with a trivial merge conflict - Minor improvements to various SoC clocksource drivers * 'timers/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: armada-370-xp: Add detailed clock requirements in devicetree binding clocksource: armada-370-xp: Get reference fixed-clock by name clocksource: armada-370-xp: Replace WARN_ON with BUG_ON clocksource: armada-370-xp: Fix device-tree binding clocksource: armada-370-xp: Introduce new compatibles clocksource: armada-370-xp: Use CLOCKSOURCE_OF_DECLARE clocksource: armada-370-xp: Simplify TIMER_CTRL register access clocksource: armada-370-xp: Use BIT() ARM: timer-sp: Set dynamic irq affinity ARM: nomadik: add dynamic irq flag to the timer clocksource: sh_cmt: 32-bit control register support clocksource: em_sti: Convert to devm_* managed helpers
2013-09-15Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull misc SCSI driver updates from James Bottomley: "This patch set is a set of driver updates (megaraid_sas, fnic, lpfc, ufs, hpsa) we also have a couple of bug fixes (sd out of bounds and ibmvfc error handling) and the first round of esas2r checker fixes and finally the much anticipated big endian additions for megaraid_sas" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (47 commits) [SCSI] fnic: fnic Driver Tuneables Exposed through CLI [SCSI] fnic: Kernel panic while running sh/nosh with max lun cfg [SCSI] fnic: Hitting BUG_ON(io_req->abts_done) in fnic_rport_exch_reset [SCSI] fnic: Remove QUEUE_FULL handling code [SCSI] fnic: On system with >1.1TB RAM, VIC fails multipath after boot up [SCSI] fnic: FC stat param seconds_since_last_reset not getting updated [SCSI] sd: Fix potential out-of-bounds access [SCSI] lpfc 8.3.42: Update lpfc version to driver version 8.3.42 [SCSI] lpfc 8.3.42: Fixed issue of task management commands having a fixed timeout [SCSI] lpfc 8.3.42: Fixed inconsistent spin lock usage. [SCSI] lpfc 8.3.42: Fix driver's abort loop functionality to skip IOs already getting aborted [SCSI] lpfc 8.3.42: Fixed failure to allocate SCSI buffer on PPC64 platform for SLI4 devices [SCSI] lpfc 8.3.42: Fix WARN_ON when driver unloads [SCSI] lpfc 8.3.42: Avoided making pci bar ioremap call during dual-chute WQ/RQ pci bar selection [SCSI] lpfc 8.3.42: Fixed driver iocbq structure's iocb_flag field running out of space [SCSI] lpfc 8.3.42: Fix crash on driver load due to cpu affinity logic [SCSI] lpfc 8.3.42: Fixed logging format of setting driver sysfs attributes hard to interpret [SCSI] lpfc 8.3.42: Fixed back to back RSCNs discovery failure. [SCSI] lpfc 8.3.42: Fixed race condition between BSG I/O dispatch and timeout handling [SCSI] lpfc 8.3.42: Fixed function mode field defined too small for not recognizing dual-chute mode ...
2013-09-15Merge branch 'slab/next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux Pull SLAB update from Pekka Enberg: "Nothing terribly exciting here apart from Christoph's kmalloc unification patches that brings sl[aou]b implementations closer to each other" * 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux: slab: Use correct GFP_DMA constant slub: remove verify_mem_not_deleted() mm/sl[aou]b: Move kmallocXXX functions to common code mm, slab_common: add 'unlikely' to size check of kmalloc_slab() mm/slub.c: beautify code for removing redundancy 'break' statement. slub: Remove unnecessary page NULL check slub: don't use cpu partial pages on UP mm/slub: beautify code for 80 column limitation and tab alignment mm/slub: remove 'per_cpu' which is useless variable
2013-09-13Merge tag 'writeback-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux Pull writeback fix from Wu Fengguang: "A trivial writeback fix" * tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Do not sort b_io list only because of block device inode
2013-09-13Merge git://git.kvack.org/~bcrl/aio-nextLinus Torvalds
Pull aio changes from Ben LaHaise: "First off, sorry for this pull request being late in the merge window. Al had raised a couple of concerns about 2 items in the series below. I addressed the first issue (the race introduced by Gu's use of mm_populate()), but he has not provided any further details on how he wants to rework the anon_inode.c changes (which were sent out months ago but have yet to be commented on). The bulk of the changes have been sitting in the -next tree for a few months, with all the issues raised being addressed" * git://git.kvack.org/~bcrl/aio-next: (22 commits) aio: rcu_read_lock protection for new rcu_dereference calls aio: fix race in ring buffer page lookup introduced by page migration support aio: fix rcu sparse warnings introduced by ioctx table lookup patch aio: remove unnecessary debugging from aio_free_ring() aio: table lookup: verify ctx pointer staging/lustre: kiocb->ki_left is removed aio: fix error handling and rcu usage in "convert the ioctx list to table lookup v3" aio: be defensive to ensure request batching is non-zero instead of BUG_ON() aio: convert the ioctx list to table lookup v3 aio: double aio_max_nr in calculations aio: Kill ki_dtor aio: Kill ki_users aio: Kill unneeded kiocb members aio: Kill aio_rw_vect_retry() aio: Don't use ctx->tail unnecessarily aio: io_cancel() no longer returns the io_event aio: percpu ioctx refcount aio: percpu reqs_available aio: reqs_active -> reqs_available aio: fix build when migration is disabled ...
2013-09-13HID: provide a helper for validating hid reportsKees Cook
Many drivers need to validate the characteristics of their HID report during initialization to avoid misusing the reports. This adds a common helper to perform validation of the report exisitng, the field existing, and the expected number of values within the field. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-09-13Remove GENERIC_HARDIRQ config optionMartin Schwidefsky
After the last architecture switched to generic hard irqs the config options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code for !CONFIG_GENERIC_HARDIRQS can be removed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-09-12Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending Pull SCSI target updates from Nicholas Bellinger: "Lots of activity again this round for I/O performance optimizations (per-cpu IDA pre-allocation for vhost + iscsi/target), and the addition of new fabric independent features to target-core (COMPARE_AND_WRITE + EXTENDED_COPY). The main highlights include: - Support for iscsi-target login multiplexing across individual network portals - Generic Per-cpu IDA logic (kent + akpm + clameter) - Conversion of vhost to use per-cpu IDA pre-allocation for descriptors, SGLs and userspace page pointer list - Conversion of iscsi-target + iser-target to use per-cpu IDA pre-allocation for descriptors - Add support for generic COMPARE_AND_WRITE (AtomicTestandSet) emulation for virtual backend drivers - Add support for generic EXTENDED_COPY (CopyOffload) emulation for virtual backend drivers. - Add support for fast memory registration mode to iser-target (Vu) The patches to add COMPARE_AND_WRITE and EXTENDED_COPY support are of particular significance, which make us the first and only open source target to support the full set of VAAI primitives. Currently Linux clients are lacking upstream support to actually utilize these primitives. However, with server side support now in place for folks like MKP + ZAB working on the client, this logic once reserved for the highest end of storage arrays, can now be run in VMs on their laptops" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (50 commits) target/iscsi: Bump versions to v4.1.0 target: Update copyright ownership/year information to 2013 iscsi-target: Bump default TCP listen backlog to 256 target: Fix >= v3.9+ regression in PR APTPL + ALUA metadata write-out iscsi-target; Bump default CmdSN Depth to 64 iscsi-target: Remove unnecessary wait_for_completion in iscsi_get_thread_set iscsi-target: Add thread_set->ts_activate_sem + use common deallocate iscsi-target: Fix race with thread_pre_handler flush_signals + ISCSI_THREAD_SET_DIE target: remove unused including <linux/version.h> iser-target: introduce fast memory registration mode (FRWR) iser-target: generalize rdma memory registration and cleanup iser-target: move rdma wr processing to a shared function target: Enable global EXTENDED_COPY setup/release target: Add Third Party Copy (3PC) bit in INQUIRY response target: Enable EXTENDED_COPY setup in spc_parse_cdb target: Add support for EXTENDED_COPY copy offload emulation target: Avoid non-existent tg_pt_gp_mem in target_alua_state_check target: Add global device list for EXTENDED_COPY target: Make helpers non static for EXTENDED_COPY command setup target: Make spc_parse_naa_6h_vendor_specific non static ...
2013-09-12Merge branch 'akpm' (patches from Andrew Morton)Linus Torvalds
Merge more patches from Andrew Morton: "The rest of MM. Plus one misc cleanup" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits) mm/Kconfig: add MMU dependency for MIGRATION. kernel: replace strict_strto*() with kstrto*() mm, thp: count thp_fault_fallback anytime thp fault fails thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page() thp: do_huge_pmd_anonymous_page() cleanup thp: move maybe_pmd_mkwrite() out of mk_huge_pmd() mm: cleanup add_to_page_cache_locked() thp: account anon transparent huge pages into NR_ANON_PAGES truncate: drop 'oldsize' truncate_pagecache() parameter mm: make lru_add_drain_all() selective memcg: document cgroup dirty/writeback memory statistics memcg: add per cgroup writeback pages accounting memcg: check for proper lock held in mem_cgroup_update_page_stat memcg: remove MEMCG_NR_FILE_MAPPED memcg: reduce function dereference memcg: avoid overflow caused by PAGE_ALIGN memcg: rename RESOURCE_MAX to RES_COUNTER_MAX memcg: correct RESOURCE_MAX to ULLONG_MAX mm: memcg: do not trap chargers with full callstack on OOM mm: memcg: rework and document OOM waiting and wakeup ...
2013-09-12thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page()Kirill A. Shutemov
do_huge_pmd_anonymous_page() has copy-pasted piece of handle_mm_fault() to handle fallback path. Let's consolidate code back by introducing VM_FAULT_FALLBACK return code. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Hillf Danton <dhillf@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Andi Kleen <ak@linux.intel.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12truncate: drop 'oldsize' truncate_pagecache() parameterKirill A. Shutemov
truncate_pagecache() doesn't care about old size since commit cedabed49b39 ("vfs: Fix vmtruncate() regression"). Let's drop it. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12mm: make lru_add_drain_all() selectiveChris Metcalf
make lru_add_drain_all() only selectively interrupt the cpus that have per-cpu free pages that can be drained. This is important in nohz mode where calling mlockall(), for example, otherwise will interrupt every core unnecessarily. This is important on workloads where nohz cores are handling 10 Gb traffic in userspace. Those CPUs do not enter the kernel and place pages into LRU pagevecs and they really, really don't want to be interrupted, or they drop packets on the floor. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Reviewed-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12memcg: add per cgroup writeback pages accountingSha Zhengju
Add memcg routines to count writeback pages, later dirty pages will also be accounted. After Kame's commit 89c06bd52fb9 ("memcg: use new logic for page stat accounting"), we can use 'struct page' flag to test page state instead of per page_cgroup flag. But memcg has a feature to move a page from a cgroup to another one and may have race between "move" and "page stat accounting". So in order to avoid the race we have designed a new lock: mem_cgroup_begin_update_page_stat() modify page information -->(a) mem_cgroup_update_page_stat() -->(b) mem_cgroup_end_update_page_stat() It requires both (a) and (b)(writeback pages accounting) to be pretected in mem_cgroup_{begin/end}_update_page_stat(). It's full no-op for !CONFIG_MEMCG, almost no-op if memcg is disabled (but compiled in), rcu read lock in the most cases (no task is moving), and spin_lock_irqsave on top in the slow path. There're two writeback interfaces to modify: test_{clear/set}_page_writeback(). And the lock order is: --> memcg->move_lock --> mapping->tree_lock Signed-off-by: Sha Zhengju <handai.szj@taobao.com> Acked-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: Greg Thelen <gthelen@google.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12memcg: remove MEMCG_NR_FILE_MAPPEDSha Zhengju
While accounting memcg page stat, it's not worth to use MEMCG_NR_FILE_MAPPED as an extra layer of indirection because of the complexity and presumed performance overhead. We can use MEM_CGROUP_STAT_FILE_MAPPED directly. Signed-off-by: Sha Zhengju <handai.szj@taobao.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Fengguang Wu <fengguang.wu@intel.com> Reviewed-by: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12memcg: rename RESOURCE_MAX to RES_COUNTER_MAXSha Zhengju
RESOURCE_MAX is far too general name, change it to RES_COUNTER_MAX. Signed-off-by: Sha Zhengju <handai.szj@taobao.com> Signed-off-by: Qiang Huang <h.huangqiang@huawei.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Jeff Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12memcg: correct RESOURCE_MAX to ULLONG_MAXSha Zhengju
Current RESOURCE_MAX is ULONG_MAX, but the value we used to set resource limit is unsigned long long, so we can set bigger value than that which is strange. The XXX_MAX should be reasonable max value, bigger than that should be overflow. Notice that this change will affect user output of default *.limit_in_bytes: before change: $ cat /cgroup/memory/memory.limit_in_bytes 9223372036854775807 after change: $ cat /cgroup/memory/memory.limit_in_bytes 18446744073709551615 But it doesn't alter the API in term of input - we can still use "echo -1 > *.limit_in_bytes" to reset the numbers to "unlimited". Signed-off-by: Sha Zhengju <handai.szj@taobao.com> Signed-off-by: Qiang Huang <h.huangqiang@huawei.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Jeff Liu <jeff.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12mm: memcg: do not trap chargers with full callstack on OOMJohannes Weiner
The memcg OOM handling is incredibly fragile and can deadlock. When a task fails to charge memory, it invokes the OOM killer and loops right there in the charge code until it succeeds. Comparably, any other task that enters the charge path at this point will go to a waitqueue right then and there and sleep until the OOM situation is resolved. The problem is that these tasks may hold filesystem locks and the mmap_sem; locks that the selected OOM victim may need to exit. For example, in one reported case, the task invoking the OOM killer was about to charge a page cache page during a write(), which holds the i_mutex. The OOM killer selected a task that was just entering truncate() and trying to acquire the i_mutex: OOM invoking task: mem_cgroup_handle_oom+0x241/0x3b0 mem_cgroup_cache_charge+0xbe/0xe0 add_to_page_cache_locked+0x4c/0x140 add_to_page_cache_lru+0x22/0x50 grab_cache_page_write_begin+0x8b/0xe0 ext3_write_begin+0x88/0x270 generic_file_buffered_write+0x116/0x290 __generic_file_aio_write+0x27c/0x480 generic_file_aio_write+0x76/0xf0 # takes ->i_mutex do_sync_write+0xea/0x130 vfs_write+0xf3/0x1f0 sys_write+0x51/0x90 system_call_fastpath+0x18/0x1d OOM kill victim: do_truncate+0x58/0xa0 # takes i_mutex do_last+0x250/0xa30 path_openat+0xd7/0x440 do_filp_open+0x49/0xa0 do_sys_open+0x106/0x240 sys_open+0x20/0x30 system_call_fastpath+0x18/0x1d The OOM handling task will retry the charge indefinitely while the OOM killed task is not releasing any resources. A similar scenario can happen when the kernel OOM killer for a memcg is disabled and a userspace task is in charge of resolving OOM situations. In this case, ALL tasks that enter the OOM path will be made to sleep on the OOM waitqueue and wait for userspace to free resources or increase the group's limit. But a userspace OOM handler is prone to deadlock itself on the locks held by the waiting tasks. For example one of the sleeping tasks may be stuck in a brk() call with the mmap_sem held for writing but the userspace handler, in order to pick an optimal victim, may need to read files from /proc/<pid>, which tries to acquire the same mmap_sem for reading and deadlocks. This patch changes the way tasks behave after detecting a memcg OOM and makes sure nobody loops or sleeps with locks held: 1. When OOMing in a user fault, invoke the OOM killer and restart the fault instead of looping on the charge attempt. This way, the OOM victim can not get stuck on locks the looping task may hold. 2. When OOMing in a user fault but somebody else is handling it (either the kernel OOM killer or a userspace handler), don't go to sleep in the charge context. Instead, remember the OOMing memcg in the task struct and then fully unwind the page fault stack with -ENOMEM. pagefault_out_of_memory() will then call back into the memcg code to check if the -ENOMEM came from the memcg, and then either put the task to sleep on the memcg's OOM waitqueue or just restart the fault. The OOM victim can no longer get stuck on any lock a sleeping task may hold. Debugged by Michal Hocko. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: azurIt <azurit@pobox.sk> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12mm: memcg: enable memcg OOM killer only for user faultsJohannes Weiner
System calls and kernel faults (uaccess, gup) can handle an out of memory situation gracefully and just return -ENOMEM. Enable the memcg OOM killer only for user faults, where it's really the only option available. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12arch: mm: pass userspace fault flag to generic fault handlerJohannes Weiner
Unlike global OOM handling, memory cgroup code will invoke the OOM killer in any OOM situation because it has no way of telling faults occuring in kernel context - which could be handled more gracefully - from user-triggered faults. Pass a flag that identifies faults originating in user space from the architecture-specific fault handlers to generic code so that memcg OOM handling can be improved. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>