Commit 5df7ae7b authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 

Pull workqueue fix from Tejun Heo:
 "One commit to fix spurious workqueue stall warnings across VM
  suspensions"

* 'for-5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  wq: handle VM suspension in stall detection
parents f71d49e0 940d71c6

kernel/workqueue.c

+10 −2
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ 
#include <linux/uaccess.h>

#include <linux/sched/isolation.h>

#include <linux/nmi.h>

#include <linux/kvm_para.h>



#include "workqueue_internal.h"
@@ -5772,6 +5773,7 @@ static void wq_watchdog_timer_fn(struct timer_list *unused) 
{

	unsigned long thresh = READ_ONCE(wq_watchdog_thresh) * HZ;

	bool lockup_detected = false;

	unsigned long now = jiffies;

	struct worker_pool *pool;

	int pi;
@@ -5786,6 +5788,12 @@ static void wq_watchdog_timer_fn(struct timer_list *unused) 
		if (list_empty(&pool->worklist))

			continue;



		/*

		 * If a virtual machine is stopped by the host it can look to

		 * the watchdog like a stall.

		 */

		kvm_check_and_clear_guest_paused();



		/* get the latest of pool and touched timestamps */

		if (pool->cpu >= 0)

			touched = READ_ONCE(per_cpu(wq_watchdog_touched_cpu, pool->cpu));
@@ -5799,12 +5807,12 @@ static void wq_watchdog_timer_fn(struct timer_list *unused) 
			ts = touched;



		/* did we stall? */

		if (time_after(jiffies, ts + thresh)) {

		if (time_after(now, ts + thresh)) {

			lockup_detected = true;

			pr_emerg("BUG: workqueue lockup - pool");

			pr_cont_pool_info(pool);

			pr_cont(" stuck for %us!\n",

				jiffies_to_msecs(jiffies - pool_ts) / 1000);

				jiffies_to_msecs(now - pool_ts) / 1000);

		}

	}