timers: Track total number of timers in list (fff42158) · Commits · 戴 / test

Currently, the tvec_base structure's ->active_timers field tracks only the non-deferrable timers, which means that even if ->active_timers is zero, there might well be deferrable timers in the list. This commit therefore adds an ->all_timers field to track all the timers, whether deferrable or not. Signed-off-by:

Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by:

Josh Triplett <josh@joshtriplett.org> Acked-by:

Peter Zijlstra <peterz@infradead.org> Reviewed-by:

Oleg Nesterov <oleg@redhat.com> Reviewed-by:

Steven Rostedt <rostedt@goodmis.org> Tested-by:

Mike Galbraith <bitbucket@online.de>

kernel/timer.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -81,6 +81,7 @@ struct tvec_base {
		unsigned long timer_jiffies;
		unsigned long next_timer;
		unsigned long active_timers;
		unsigned long all_timers;
		struct tvec_root tv1;
		struct tvec tv2;
		struct tvec tv3;
		@@ -392,6 +393,7 @@ static void internal_add_timer(struct tvec_base base, struct timer_list timer)
		base->next_timer = timer->expires;
		base->active_timers++;
		}
		base->all_timers++;
		}

		#ifdef CONFIG_TIMER_STATS
		@@ -671,6 +673,7 @@ detach_expired_timer(struct timer_list timer, struct tvec_base base)
		detach_timer(timer, true);
		if (!tbase_get_deferrable(timer->base))
		base->active_timers--;
		base->all_timers--;
		}

		static int detach_if_pending(struct timer_list timer, struct tvec_base base,
		@@ -685,6 +688,7 @@ static int detach_if_pending(struct timer_list timer, struct tvec_base base,
		if (timer->expires == base->next_timer)
		base->next_timer = base->timer_jiffies;
		}
		base->all_timers--;
		return 1;
		}

		@@ -1559,6 +1563,7 @@ static int init_timers_cpu(int cpu)
		base->timer_jiffies = jiffies;
		base->next_timer = base->timer_jiffies;
		base->active_timers = 0;
		base->all_timers = 0;
		return 0;
		}

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