diff options
Diffstat (limited to 'kernel/time/timekeeping.c')
| -rw-r--r-- | kernel/time/timekeeping.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 7033ac1fee65..19414b16cf9e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1519,8 +1519,20 @@ void __weak read_boot_clock64(struct timespec64 *ts) ts->tv_nsec = 0; } -/* Flag for if timekeeping_resume() has injected sleeptime */ -static bool sleeptime_injected; +/* + * Flag reflecting whether timekeeping_resume() has injected sleeptime. + * + * The flag starts of false and is only set when a suspend reaches + * timekeeping_suspend(), timekeeping_resume() sets it to false when the + * timekeeper clocksource is not stopping across suspend and has been + * used to update sleep time. If the timekeeper clocksource has stopped + * then the flag stays true and is used by the RTC resume code to decide + * whether sleeptime must be injected and if so the flag gets false then. + * + * If a suspend fails before reaching timekeeping_resume() then the flag + * stays false and prevents erroneous sleeptime injection. + */ +static bool suspend_timing_needed; /* Flag for if there is a persistent clock on this platform */ static bool persistent_clock_exists; @@ -1619,7 +1631,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, */ bool timekeeping_rtc_skipresume(void) { - return sleeptime_injected; + return !suspend_timing_needed; } /** @@ -1655,6 +1667,8 @@ void timekeeping_inject_sleeptime64(const struct timespec64 *delta) raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&tk_core.seq); + suspend_timing_needed = false; + timekeeping_forward_now(tk); __timekeeping_inject_sleeptime(tk, delta); @@ -1679,8 +1693,8 @@ void timekeeping_resume(void) unsigned long flags; struct timespec64 ts_new, ts_delta; u64 cycle_now; + bool inject_sleeptime = false; - sleeptime_injected = false; read_persistent_clock64(&ts_new); clockevents_resume(); @@ -1710,14 +1724,16 @@ void timekeeping_resume(void) tk->tkr_mono.mask); nsec = mul_u64_u32_shr(cyc_delta, clock->mult, clock->shift); ts_delta = ns_to_timespec64(nsec); - sleeptime_injected = true; + inject_sleeptime = true; } else if (timespec64_compare(&ts_new, &timekeeping_suspend_time) > 0) { ts_delta = timespec64_sub(ts_new, timekeeping_suspend_time); - sleeptime_injected = true; + inject_sleeptime = true; } - if (sleeptime_injected) + if (inject_sleeptime) { + suspend_timing_needed = false; __timekeeping_inject_sleeptime(tk, &ts_delta); + } /* Re-base the last cycle value */ tk->tkr_mono.cycle_last = cycle_now; @@ -1752,6 +1768,8 @@ int timekeeping_suspend(void) if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec) persistent_clock_exists = true; + suspend_timing_needed = true; + raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&tk_core.seq); timekeeping_forward_now(tk); |