On 03/11/2014 08:40 AM, tip-bot for Mike Galbraith wrote: > Commit-ID: 156654f491dd8d52687a5fbe1637f472a52ce75b > Gitweb: http://git.kernel.org/tip/156654f491dd8d52687a5fbe1637f472a52ce75b > Author: Mike Galbraith <bitbucket@xxxxxxxxx> > AuthorDate: Fri, 28 Feb 2014 07:23:11 +0100 > Committer: Ingo Molnar <mingo@xxxxxxxxxx> > CommitDate: Tue, 11 Mar 2014 12:05:43 +0100 > > sched/numa: Move task_numa_free() to __put_task_struct() > > Bad idea on -rt: > > [ 908.026136] [<ffffffff8150ad6a>] rt_spin_lock_slowlock+0xaa/0x2c0 > [ 908.026145] [<ffffffff8108f701>] task_numa_free+0x31/0x130 > [ 908.026151] [<ffffffff8108121e>] finish_task_switch+0xce/0x100 > [ 908.026156] [<ffffffff81509c0a>] thread_return+0x48/0x4ae > [ 908.026160] [<ffffffff8150a095>] schedule+0x25/0xa0 > [ 908.026163] [<ffffffff8150ad95>] rt_spin_lock_slowlock+0xd5/0x2c0 > [ 908.026170] [<ffffffff810658cf>] get_signal_to_deliver+0xaf/0x680 > [ 908.026175] [<ffffffff8100242d>] do_signal+0x3d/0x5b0 > [ 908.026179] [<ffffffff81002a30>] do_notify_resume+0x90/0xe0 > [ 908.026186] [<ffffffff81513176>] int_signal+0x12/0x17 > [ 908.026193] [<00007ff2a388b1d0>] 0x7ff2a388b1cf > > and since upstream does not mind where we do this, be a bit nicer ... > > Signed-off-by: Mike Galbraith <bitbucket@xxxxxxxxx> > Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxxx> > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Link: http://lkml.kernel.org/r/1393568591.6018.27.camel@xxxxxxxxxxxxxxxxx > Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> As it seems, upstream does mind: [ 2590.260734] ====================================================== [ 2590.261695] [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ] [ 2590.262748] 3.14.0-next-20140403-sasha-00022-g10224c0 #377 Tainted: G W [ 2590.263846] ------------------------------------------------------ [ 2590.264730] trinity-c244/1210 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: [ 2590.265783] (&(&grp->lock)->rlock){+.+...}, at: task_numa_free (kernel/sched/fair.c:1714) [ 2590.267179] [ 2590.267179] and this task is already holding: [ 2590.267996] (&(&new_timer->it_lock)->rlock){-.....}, at: exit_itimers (kernel/posix-timers.c:971 kernel/posix-timers.c:998) [ 2590.269381] which would create a new lock dependency: [ 2590.270067] (&(&new_timer->it_lock)->rlock){-.....} -> (&(&grp->lock)->rlock){+.+...} [ 2590.270067] [ 2590.270067] but this new dependency connects a HARDIRQ-irq-safe lock: [ 2590.270067] (&(&new_timer->it_lock)->rlock){-.....} ... which became HARDIRQ-irq-safe at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:2783 kernel/locking/lockdep.c:3138) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:117 kernel/locking/spinlock.c:159) [ 2590.270067] posix_timer_fn (kernel/posix-timers.c:437) [ 2590.270067] __run_hrtimer (kernel/hrtimer.c:1245 (discriminator 2)) [ 2590.270067] hrtimer_interrupt (kernel/hrtimer.c:1892) [ 2590.270067] local_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:921) [ 2590.270067] smp_apic_timer_interrupt (arch/x86/include/asm/apic.h:696 arch/x86/kernel/apic/apic.c:945) [ 2590.270067] apic_timer_interrupt (arch/x86/kernel/entry_64.S:1164) [ 2590.270067] default_idle (arch/x86/include/asm/paravirt.h:111 arch/x86/kernel/process.c:310) [ 2590.270067] arch_cpu_idle (arch/x86/kernel/process.c:302) [ 2590.270067] cpu_idle_loop (kernel/sched/idle.c:179 kernel/sched/idle.c:226) [ 2590.270067] cpu_startup_entry (??:?) [ 2590.270067] start_secondary (arch/x86/kernel/smpboot.c:267) [ 2590.270067] [ 2590.270067] to a HARDIRQ-irq-unsafe lock: [ 2590.270067] (&(&grp->lock)->rlock){+.+...} ... which became HARDIRQ-irq-unsafe at: [ 2590.270067] ... __lock_acquire (kernel/locking/lockdep.c:2800 kernel/locking/lockdep.c:3138) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_placement (include/linux/nodemask.h:248 kernel/sched/fair.c:1504) [ 2590.270067] task_numa_fault (kernel/sched/fair.c:1794) [ 2590.270067] __handle_mm_fault (mm/memory.c:3796 mm/memory.c:3796 mm/memory.c:3909) [ 2590.270067] handle_mm_fault (include/linux/memcontrol.h:148 mm/memory.c:3935) [ 2590.270067] __do_page_fault (arch/x86/mm/fault.c:1220) [ 2590.270067] do_page_fault (arch/x86/mm/fault.c:1272 include/linux/jump_label.h:105 include/linux/context_tracking_state.h:27 include/linux/context_tracking.h:45 arch/x86/mm/fault.c:1273) [ 2590.270067] do_async_page_fault (arch/x86/kernel/kvm.c:263) [ 2590.270067] async_page_fault (arch/x86/kernel/entry_64.S:1496) [ 2590.270067] [ 2590.270067] other info that might help us debug this: [ 2590.270067] [ 2590.270067] Possible interrupt unsafe locking scenario: [ 2590.270067] [ 2590.270067] CPU0 CPU1 [ 2590.270067] ---- ---- [ 2590.270067] lock(&(&grp->lock)->rlock); [ 2590.270067] local_irq_disable(); [ 2590.270067] lock(&(&new_timer->it_lock)->rlock); [ 2590.270067] lock(&(&grp->lock)->rlock); [ 2590.270067] <Interrupt> [ 2590.270067] lock(&(&new_timer->it_lock)->rlock); [ 2590.270067] [ 2590.270067] *** DEADLOCK *** [ 2590.270067] [ 2590.270067] 1 lock held by trinity-c244/1210: [ 2590.270067] #0: (&(&new_timer->it_lock)->rlock){-.....}, at: exit_itimers (kernel/posix-timers.c:971 kernel/posix-timers.c:998) [ 2590.270067] the dependencies between HARDIRQ-irq-safe lock and the holding lock: [ 2590.270067] -> (&(&new_timer->it_lock)->rlock){-.....} ops: 361 { [ 2590.270067] IN-HARDIRQ-W at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:2783 kernel/locking/lockdep.c:3138) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:117 kernel/locking/spinlock.c:159) [ 2590.270067] posix_timer_fn (kernel/posix-timers.c:437) [ 2590.270067] __run_hrtimer (kernel/hrtimer.c:1245 (discriminator 2)) [ 2590.270067] hrtimer_interrupt (kernel/hrtimer.c:1892) [ 2590.270067] local_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:921) [ 2590.270067] smp_apic_timer_interrupt (arch/x86/include/asm/apic.h:696 arch/x86/kernel/apic/apic.c:945) [ 2590.270067] apic_timer_interrupt (arch/x86/kernel/entry_64.S:1164) [ 2590.270067] default_idle (arch/x86/include/asm/paravirt.h:111 arch/x86/kernel/process.c:310) [ 2590.270067] arch_cpu_idle (arch/x86/kernel/process.c:302) [ 2590.270067] cpu_idle_loop (kernel/sched/idle.c:179 kernel/sched/idle.c:226) [ 2590.270067] cpu_startup_entry (??:?) [ 2590.270067] start_secondary (arch/x86/kernel/smpboot.c:267) [ 2590.270067] INITIAL USE at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:3142) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:117 kernel/locking/spinlock.c:159) [ 2590.270067] exit_itimers (kernel/posix-timers.c:971 kernel/posix-timers.c:998) [ 2590.270067] do_exit (kernel/exit.c:766) [ 2590.270067] do_group_exit (kernel/exit.c:919) [ 2590.270067] SyS_exit_group (kernel/exit.c:930) [ 2590.270067] tracesys (arch/x86/kernel/entry_64.S:749) [ 2590.270067] } [ 2590.270067] ... key at: __key.33130 (??:?) [ 2590.270067] ... acquired at: [ 2590.270067] check_irq_usage (kernel/locking/lockdep.c:1638) [ 2590.270067] __lock_acquire (kernel/locking/lockdep_states.h:7 kernel/locking/lockdep.c:1844 kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131 kernel/locking/lockdep.c:3182) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_free (kernel/sched/fair.c:1714) [ 2590.270067] __put_task_struct (kernel/fork.c:244 (discriminator 2)) [ 2590.270067] posix_cpu_timer_del (include/linux/sched.h:1807 kernel/posix-cpu-timers.c:409) [ 2590.270067] exit_itimers (kernel/posix-timers.c:973 kernel/posix-timers.c:998) [ 2590.270067] do_exit (kernel/exit.c:766) [ 2590.270067] do_group_exit (kernel/exit.c:919) [ 2590.270067] SyS_exit_group (kernel/exit.c:930) [ 2590.270067] tracesys (arch/x86/kernel/entry_64.S:749) [ 2590.270067] [ 2590.270067] the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: [ 2590.270067] -> (&(&grp->lock)->rlock){+.+...} ops: 91 { [ 2590.270067] HARDIRQ-ON-W at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:2800 kernel/locking/lockdep.c:3138) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_placement (include/linux/nodemask.h:248 kernel/sched/fair.c:1504) [ 2590.270067] task_numa_fault (kernel/sched/fair.c:1794) [ 2590.270067] __handle_mm_fault (mm/memory.c:3796 mm/memory.c:3796 mm/memory.c:3909) [ 2590.270067] handle_mm_fault (include/linux/memcontrol.h:148 mm/memory.c:3935) [ 2590.270067] __do_page_fault (arch/x86/mm/fault.c:1220) [ 2590.270067] do_page_fault (arch/x86/mm/fault.c:1272 include/linux/jump_label.h:105 include/linux/context_tracking_state.h:27 include/linux/context_tracking.h:45 arch/x86/mm/fault.c:1273) [ 2590.270067] do_async_page_fault (arch/x86/kernel/kvm.c:263) [ 2590.270067] async_page_fault (arch/x86/kernel/entry_64.S:1496) [ 2590.270067] SOFTIRQ-ON-W at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:2804 kernel/locking/lockdep.c:3138) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_placement (include/linux/nodemask.h:248 kernel/sched/fair.c:1504) [ 2590.270067] task_numa_fault (kernel/sched/fair.c:1794) [ 2590.270067] __handle_mm_fault (mm/memory.c:3796 mm/memory.c:3796 mm/memory.c:3909) [ 2590.270067] handle_mm_fault (include/linux/memcontrol.h:148 mm/memory.c:3935) [ 2590.270067] __do_page_fault (arch/x86/mm/fault.c:1220) [ 2590.270067] do_page_fault (arch/x86/mm/fault.c:1272 include/linux/jump_label.h:105 include/linux/context_tracking_state.h:27 include/linux/context_tracking.h:45 arch/x86/mm/fault.c:1273) [ 2590.270067] do_async_page_fault (arch/x86/kernel/kvm.c:263) [ 2590.270067] async_page_fault (arch/x86/kernel/entry_64.S:1496) [ 2590.270067] INITIAL USE at: [ 2590.270067] __lock_acquire (kernel/locking/lockdep.c:3142) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_placement (include/linux/nodemask.h:248 kernel/sched/fair.c:1504) [ 2590.270067] task_numa_fault (kernel/sched/fair.c:1794) [ 2590.270067] __handle_mm_fault (mm/memory.c:3796 mm/memory.c:3796 mm/memory.c:3909) [ 2590.270067] handle_mm_fault (include/linux/memcontrol.h:148 mm/memory.c:3935) [ 2590.270067] __do_page_fault (arch/x86/mm/fault.c:1220) [ 2590.270067] do_page_fault (arch/x86/mm/fault.c:1272 include/linux/jump_label.h:105 include/linux/context_tracking_state.h:27 include/linux/context_tracking.h:45 arch/x86/mm/fault.c:1273) [ 2590.270067] do_async_page_fault (arch/x86/kernel/kvm.c:263) [ 2590.270067] async_page_fault (arch/x86/kernel/entry_64.S:1496) [ 2590.270067] } [ 2590.270067] ... key at: __key.32449 (??:?) [ 2590.270067] ... acquired at: [ 2590.270067] check_irq_usage (kernel/locking/lockdep.c:1638) [ 2590.270067] __lock_acquire (kernel/locking/lockdep_states.h:7 kernel/locking/lockdep.c:1844 kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131 kernel/locking/lockdep.c:3182) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] task_numa_free (kernel/sched/fair.c:1714) [ 2590.270067] __put_task_struct (kernel/fork.c:244 (discriminator 2)) [ 2590.270067] posix_cpu_timer_del (include/linux/sched.h:1807 kernel/posix-cpu-timers.c:409) [ 2590.270067] exit_itimers (kernel/posix-timers.c:973 kernel/posix-timers.c:998) [ 2590.270067] do_exit (kernel/exit.c:766) [ 2590.270067] do_group_exit (kernel/exit.c:919) [ 2590.270067] SyS_exit_group (kernel/exit.c:930) [ 2590.270067] tracesys (arch/x86/kernel/entry_64.S:749) [ 2590.270067] [ 2590.270067] [ 2590.270067] stack backtrace: [ 2590.270067] CPU: 3 PID: 1210 Comm: trinity-c244 Tainted: G W 3.14.0-next-20140403-sasha-00022-g10224c0 #377 [ 2590.270067] ffffffff87a83b60 ffff880081695ad8 ffffffff844bfb3f 0000000000000000 [ 2590.270067] ffff880081698cf0 ffff880081695be8 ffffffff811c0d05 0000000000000000 [ 2590.270067] ffffffff00000000 ffff880000000001 ffffffff8107aac5 ffff880081695b38 [ 2590.270067] Call Trace: [ 2590.270067] dump_stack (lib/dump_stack.c:52) [ 2590.270067] check_usage (kernel/locking/lockdep.c:1549 kernel/locking/lockdep.c:1580) [ 2590.270067] ? sched_clock (arch/x86/include/asm/paravirt.h:192 arch/x86/kernel/tsc.c:305) [ 2590.270067] ? sched_clock_cpu (kernel/sched/clock.c:311) [ 2590.270067] check_irq_usage (kernel/locking/lockdep.c:1638) [ 2590.270067] __lock_acquire (kernel/locking/lockdep_states.h:7 kernel/locking/lockdep.c:1844 kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131 kernel/locking/lockdep.c:3182) [ 2590.270067] ? __lock_acquire (kernel/locking/lockdep.c:3189) [ 2590.270067] lock_acquire (arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602) [ 2590.270067] ? task_numa_free (kernel/sched/fair.c:1714) [ 2590.270067] _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151) [ 2590.270067] ? task_numa_free (kernel/sched/fair.c:1714) [ 2590.270067] ? trace_hardirqs_off_caller (kernel/locking/lockdep.c:2638 (discriminator 2)) [ 2590.270067] task_numa_free (kernel/sched/fair.c:1714) [ 2590.270067] __put_task_struct (kernel/fork.c:244 (discriminator 2)) [ 2590.270067] posix_cpu_timer_del (include/linux/sched.h:1807 kernel/posix-cpu-timers.c:409) [ 2590.270067] exit_itimers (kernel/posix-timers.c:973 kernel/posix-timers.c:998) [ 2590.270067] do_exit (kernel/exit.c:766) [ 2590.270067] ? __this_cpu_preempt_check (lib/smp_processor_id.c:63) [ 2590.270067] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2557 kernel/locking/lockdep.c:2599) [ 2590.270067] ? trace_hardirqs_on (kernel/locking/lockdep.c:2607) [ 2590.270067] do_group_exit (kernel/exit.c:919) [ 2590.270067] SyS_exit_group (kernel/exit.c:930) [ 2590.270067] tracesys (arch/x86/kernel/entry_64.S:749) Thanks, Sasha -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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