From 2b473e65dea6be1a60d357f0afe46ecb6bf91501 Mon Sep 17 00:00:00 2001 From: Anna-Maria Behnsen Date: Wed, 9 Oct 2024 10:29:13 +0200 Subject: [PATCH] timekeeping: Rework timekeeping_inject_sleeptime64() to use shadow_timekeeper Updates of the timekeeper can be done by operating on the shadow timekeeper and afterwards copying the result into the real timekeeper. This has the advantage, that the sequence count write protected region is kept as small as possible. Convert timekeeping_inject_sleeptime64() to use this scheme. Signed-off-by: Anna-Maria Behnsen Signed-off-by: Thomas Gleixner Acked-by: John Stultz Link: https://lore.kernel.org/all/20241009-devel-anna-maria-b4-timers-ptp-timekeeping-v2-20-554456a44a15@linutronix.de --- kernel/time/timekeeping.c | 22 +++++++--------------- 1 file changed, 7 insertions(+), 15 deletions(-) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 4e0037d342d8..9552bc76f386 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1924,22 +1924,14 @@ bool timekeeping_rtc_skipsuspend(void) */ void timekeeping_inject_sleeptime64(const struct timespec64 *delta) { - struct timekeeper *tk = &tk_core.timekeeper; - unsigned long flags; - - raw_spin_lock_irqsave(&tk_core.lock, flags); - write_seqcount_begin(&tk_core.seq); - - suspend_timing_needed = false; - - timekeeping_forward_now(tk); - - __timekeeping_inject_sleeptime(tk, delta); - - timekeeping_update(&tk_core, tk, TK_UPDATE_ALL | TK_MIRROR); + scoped_guard(raw_spinlock_irqsave, &tk_core.lock) { + struct timekeeper *tks = &tk_core.shadow_timekeeper; - write_seqcount_end(&tk_core.seq); - raw_spin_unlock_irqrestore(&tk_core.lock, flags); + suspend_timing_needed = false; + timekeeping_forward_now(tks); + __timekeeping_inject_sleeptime(tks, delta); + timekeeping_update_from_shadow(&tk_core, TK_UPDATE_ALL); + } /* Signal hrtimers about time change */ clock_was_set(CLOCK_SET_WALL | CLOCK_SET_BOOT); -- 2.50.1