Any input on this ? Thanks, Mukesh On 5/30/2018 5:14 PM, Mukesh Ojha wrote:
Currently, for both non-stop clocksource and persistent clock there is a corner case, when a driver failed to go suspend mode. rtc_resume() injects the sleeptime as timekeeping_rtc_skipresume() returned 'false'(sleeptime_injected=false) due to which we can see mismatch in timestamps between system clock and other timers.Fix this by updating sleeptime_injected=true for both non-stop clocksource and persistent clock. Success case: ------------ {sleeptime_injected=true} rtc_suspend() => timekeeping_suspend() => timekeeping_resume() => rtc_resume() Failure case: ------------ {failure in sleep path} {sleeptime_injected=false} rtc_suspend() => rtc_resume() Signed-off-by: Mukesh Ojha <mo...@codeaurora.org> --- Changes in v2: * Updated the commit text. * Removed extra variable and used the earlier static variable 'sleeptime_injected'. kernel/time/timekeeping.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 49cbcee..2754c1b 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1610,6 +1610,17 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, */ bool timekeeping_rtc_skipresume(void) { + struct timekeeper *tk = &tk_core.timekeeper; + /* + * This is to ensure that we don't end up injecting + * the sleeptime via rtc_resume() for non-stop clocksource + * when we fail to sleep. + */ + if (!sleeptime_injected) + sleeptime_injected = ((tk->tkr_mono.clock->flags & + CLOCK_SOURCE_SUSPEND_NONSTOP) || + (persistent_clock_exists)) ? true : false; + return sleeptime_injected; }
