[tip: timers/core] timekeeping: Don't stop time readers across hard_pps() update

tip-bot2 for Thomas Gleixner posted 1 patch 1 month ago
There is a newer version of this series
kernel/time/timekeeping.c | 4 ----
1 file changed, 4 deletions(-)
[tip: timers/core] timekeeping: Don't stop time readers across hard_pps() update
Posted by tip-bot2 for Thomas Gleixner 1 month ago
The following commit has been merged into the timers/core branch of tip:

Commit-ID:     708573a8f75ec94e9063d6c47e0571bcf39f0bb0
Gitweb:        https://git.kernel.org/tip/708573a8f75ec94e9063d6c47e0571bcf39f0bb0
Author:        Thomas Gleixner <tglx@linutronix.de>
AuthorDate:    Wed, 09 Oct 2024 10:28:55 +02:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Fri, 25 Oct 2024 16:41:11 +02:00

timekeeping: Don't stop time readers across hard_pps() update

From: Thomas Gleixner <tglx@linutronix.de>

hard_pps() update does not modify anything which might be required by time
readers so forcing readers out of the way during the update is a pointless
exercise.

The interaction with adjtimex() and timekeeper updates which call into the
NTP code is properly serialized by timekeeper_lock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241009-devel-anna-maria-b4-timers-ptp-timekeeping-v2-2-554456a44a15@linutronix.de

---
 kernel/time/timekeeping.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 2bc3542..ff98a0b 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -2746,11 +2746,7 @@ void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&timekeeper_lock, flags);
-	write_seqcount_begin(&tk_core.seq);
-
 	__hardpps(phase_ts, raw_ts);
-
-	write_seqcount_end(&tk_core.seq);
 	raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
 }
 EXPORT_SYMBOL(hardpps);