The following commit has been merged into the timers/core branch of tip:
Commit-ID: bd29d773ea8d2c7fc36dc3f70d4c9d1cf404aa4b
Gitweb: https://git.kernel.org/tip/bd29d773ea8d2c7fc36dc3f70d4c9d1cf404aa4b
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Mon, 10 Jun 2024 18:42:21 +02:00
Committer: Frederic Weisbecker <frederic@xxxxxxxxxx>
CommitterDate: Mon, 29 Jul 2024 21:57:34 +02:00
posix-cpu-timers: Do not arm SIGEV_NONE timers
There is no point in arming SIGEV_NONE timers as they never deliver a
signal. timer_gettime() is handling the expiry time correctly and that's
all SIGEV_NONE timers care about.
Prevent arming them and remove the expiry handler code which just disarms
them.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Reviewed-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
kernel/time/posix-cpu-timers.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 040d5c3..62e6b90 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -584,12 +584,7 @@ static void cpu_timer_fire(struct k_itimer *timer)
{
struct cpu_timer *ctmr = &timer->it.cpu;
- if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
- /*
- * User don't want any signal.
- */
- cpu_timer_setexpires(ctmr, 0);
- } else if (unlikely(timer->sigq == NULL)) {
+ if (unlikely(timer->sigq == NULL)) {
/*
* This a special case for clock_nanosleep,
* not a normal timer from sys_timer_create.
@@ -625,6 +620,7 @@ static void __posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *i
static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
struct itimerspec64 *new, struct itimerspec64 *old)
{
+ bool sigev_none = timer->it_sigev_notify == SIGEV_NONE;
clockid_t clkid = CPUCLOCK_WHICH(timer->it_clock);
u64 old_expires, new_expires, old_incr, val;
struct cpu_timer *ctmr = &timer->it.cpu;
@@ -688,7 +684,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
if (CPUCLOCK_PERTHREAD(timer->it_clock))
val = cpu_clock_sample(clkid, p);
else
- val = cpu_clock_sample_group(clkid, p, true);
+ val = cpu_clock_sample_group(clkid, p, !sigev_none);
/* Retrieve the previous expiry value if requested. */
if (old) {
@@ -708,19 +704,20 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
goto out;
}
- if (new_expires != 0 && !(timer_flags & TIMER_ABSTIME)) {
+ /* Convert relative expiry time to absolute */
+ if (new_expires && !(timer_flags & TIMER_ABSTIME))
new_expires += val;
- }
+
+ /* Set the new expiry time (might be 0) */
+ cpu_timer_setexpires(ctmr, new_expires);
/*
- * Install the new expiry time (or zero).
- * For a timer with no notification action, we don't actually
- * arm the timer (we'll just fake it for timer_gettime).
+ * Arm the timer if it is not disabled, the new expiry value has
+ * not yet expired and the timer requires signal delivery.
+ * SIGEV_NONE timers are never armed.
*/
- cpu_timer_setexpires(ctmr, new_expires);
- if (new_expires != 0 && val < new_expires) {
+ if (!sigev_none && new_expires && val < new_expires)
arm_timer(timer, p);
- }
unlock_task_sighand(p, &flags);
/*
@@ -739,7 +736,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
timer->it_overrun_last = 0;
timer->it_overrun = -1;
- if (val >= new_expires) {
+ if (!sigev_none && val >= new_expires) {
if (new_expires != 0) {
/*
* The designated time already passed, so we notify
|