Commit 0f8c7901 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 

Pull workqueue update from Tejun Heo:
 "Workqueue changes for v4.5.  One cleanup patch and three to improve
  the debuggability.

  Workqueue now has a stall detector which dumps workqueue state if any
  worker pool hasn't made forward progress over a certain amount of time
  (30s by default) and also triggers a warning if a workqueue which can
  be used in memory reclaim path tries to wait on something which can't
  be.

  These should make workqueue hangs a lot easier to debug."

* 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: simplify the apply_workqueue_attrs_locked()
  workqueue: implement lockup detector
  watchdog: introduce touch_softlockup_watchdog_sched()
  workqueue: warn if memory reclaim tries to flush !WQ_MEM_RECLAIM workqueue
parents 3d116a66 6201171e

Documentation/kernel-parameters.txt

+9 −0
Original line number Diff line number Diff line
@@ -4140,6 +4140,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted. 
			or other driver-specific files in the

			Documentation/watchdog/ directory.



	workqueue.watchdog_thresh=

			If CONFIG_WQ_WATCHDOG is configured, workqueue can

			warn stall conditions and dump internal state to

			help debugging.  0 disables workqueue stall

			detection; otherwise, it's the stall threshold

			duration in seconds.  The default value is 30 and

			it can be updated at runtime by writing to the

			corresponding sysfs file.



	workqueue.disable_numa

			By default, all work items queued to unbound

			workqueues are affine to the NUMA nodes they're

include/linux/sched.h

+4 −0
Original line number Diff line number Diff line
@@ -377,6 +377,7 @@ extern void scheduler_tick(void); 
extern void sched_show_task(struct task_struct *p);



#ifdef CONFIG_LOCKUP_DETECTOR

extern void touch_softlockup_watchdog_sched(void);

extern void touch_softlockup_watchdog(void);

extern void touch_softlockup_watchdog_sync(void);

extern void touch_all_softlockup_watchdogs(void);
@@ -387,6 +388,9 @@ extern unsigned int softlockup_panic; 
extern unsigned int  hardlockup_panic;

void lockup_detector_init(void);

#else

static inline void touch_softlockup_watchdog_sched(void)

{

}

static inline void touch_softlockup_watchdog(void)

{

}

include/linux/workqueue.h

+6 −0
Original line number Diff line number Diff line
@@ -618,4 +618,10 @@ static inline int workqueue_sysfs_register(struct workqueue_struct *wq) 
{ return 0; }

#endif	/* CONFIG_SYSFS */



#ifdef CONFIG_WQ_WATCHDOG

void wq_watchdog_touch(int cpu);

#else	/* CONFIG_WQ_WATCHDOG */

static inline void wq_watchdog_touch(int cpu) { }

#endif	/* CONFIG_WQ_WATCHDOG */



#endif

kernel/sched/clock.c

+1 −1
Original line number Diff line number Diff line
@@ -354,7 +354,7 @@ void sched_clock_idle_wakeup_event(u64 delta_ns) 
		return;



	sched_clock_tick();

	touch_softlockup_watchdog();

	touch_softlockup_watchdog_sched();

}

EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);

kernel/time/tick-sched.c

+3 −3
Original line number Diff line number Diff line
@@ -143,7 +143,7 @@ static void tick_sched_handle(struct tick_sched *ts, struct pt_regs *regs) 
	 * when we go busy again does not account too much ticks.

	 */

	if (ts->tick_stopped) {

		touch_softlockup_watchdog();

		touch_softlockup_watchdog_sched();

		if (is_idle_task(current))

			ts->idle_jiffies++;

	}
@@ -430,7 +430,7 @@ static void tick_nohz_update_jiffies(ktime_t now) 
	tick_do_update_jiffies64(now);

	local_irq_restore(flags);



	touch_softlockup_watchdog();

	touch_softlockup_watchdog_sched();

}



/*
@@ -717,7 +717,7 @@ static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now, int 
	update_cpu_load_nohz(active);



	calc_load_exit_idle();

	touch_softlockup_watchdog();

	touch_softlockup_watchdog_sched();

	/*

	 * Cancel the scheduled timer and restore the tick

	 */

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