On 08-06-18, 09:07, Chen Yu wrote: > According to current code implementation, detecting the long > idle period is done by checking if the interval between two > adjacent utilization update handers is long enough. Although > this mechanism can detect if the idle period is long enough > (no utilization hooks invoked during idle period), it might > not contain a corner case: if the task has occupied the cpu > for too long which causes no context switch during that > period, then no utilization handler will be launched until this > high prio task is switched out. As a result, the idle_periods > field might be calculated incorrectly because it regards the > 100% load as 0% and makes the conservative governor who uses > this field confusing. > > Change the judgement to compare the idle_time with sampling_rate > directly. > > Reported-by: Artem S. Tashkinov <[email protected]> > Cc: Artem S Tashkinov <[email protected]> > Cc: "Rafael J. Wysocki" <[email protected]> > Cc: Viresh Kumar <[email protected]> > Cc: [email protected] > Signed-off-by: Chen Yu <[email protected]> > --- > v2: Per Viresh's suggestion, ignore idle_time longer than 30mins and > simplify the code. > --- > drivers/cpufreq/cpufreq_governor.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-)
Acked-by: Viresh Kumar <[email protected]> -- viresh
