On Tue, Dec 11, 2018 at 06:11:25PM +0300, Kirill Tkhai wrote: > ksm thread unconditionally sleeps in ksm_scan_thread() > after each iteration: > > schedule_timeout_interruptible( > msecs_to_jiffies(ksm_thread_sleep_millisecs)) > > The timeout is configured in /sys/kernel/mm/ksm/sleep_millisecs. > > In case of user writes a big value by a mistake, and the thread > enters into schedule_timeout_interruptible(), it's not possible > to cancel the sleep by writing a new smaler value; the thread > is just sleeping till timeout expires. > > The patch fixes the problem by waking the thread each time > after the value is updated. > > This also may be useful for debug purposes; and also for userspace > daemons, which change sleep_millisecs value in dependence of > system load. > > Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx> > > v3: Do not use mutex: to acquire it may take much time in case long > list of ksm'able mm and pages. > v2: Use wait_event_interruptible_timeout() instead of unconditional > schedule_timeout(). Looks ok to me, thanks! Acked-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>
