Commits
Paul E. McKenney committed 18d8cb64c9c
timers: Reduce future __run_timers() latency for first add to empty list The __run_timers() function currently steps through the list one jiffy at a time in order to update the timer wheel. However, if the timer wheel is empty, no adjustment is needed other than updating ->timer_jiffies. Therefore, just before we add a timer to an empty timer wheel, we should mark the timer wheel as being up to date. This marking will reduce (and perhaps eliminate) the jiffy-stepping that a future __run_timers() call will need to do in response to some future timer posting or migration. This commit therefore updates ->timer_jiffies for this case. 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>