From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Anna-Maria Behnsen <anna-maria@linutronix.de>,
Frederic Weisbecker <frederic@kernel.org>,
John Stultz <jstultz@google.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>, Stephen Boyd <sboyd@kernel.org>,
Eric Biederman <ebiederm@xmission.com>,
Oleg Nesterov <oleg@redhat.com>
Subject: [patch V2 14/50] posix-cpu-timers: Use @now instead of @val for clarity
Date: Thu, 11 Apr 2024 00:46:36 +0200 (CEST) [thread overview]
Message-ID: <20240410165551.819762665@linutronix.de> (raw)
In-Reply-To: <20240410164558.316665885@linutronix.de>
posix_cpu_timer_set() uses @val as variable for the current time. That's
confusing at best.
Use @now as anywhere else and rewrite the confusing comment about clock
sampling.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
---
kernel/time/posix-cpu-timers.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -622,7 +622,7 @@ static int posix_cpu_timer_set(struct k_
{
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;
+ u64 old_expires, new_expires, old_incr, now;
struct cpu_timer *ctmr = &timer->it.cpu;
struct sighand_struct *sighand;
struct task_struct *p;
@@ -674,23 +674,19 @@ static int posix_cpu_timer_set(struct k_
}
/*
- * We need to sample the current value to convert the new
- * value from to relative and absolute, and to convert the
- * old value from absolute to relative. To set a process
- * timer, we need a sample to balance the thread expiry
- * times (in arm_timer). With an absolute time, we must
- * check if it's already passed. In short, we need a sample.
+ * Sample the current clock for saving the previous setting
+ * and for rearming the timer.
*/
if (CPUCLOCK_PERTHREAD(timer->it_clock))
- val = cpu_clock_sample(clkid, p);
+ now = cpu_clock_sample(clkid, p);
else
- val = cpu_clock_sample_group(clkid, p, !sigev_none);
+ now = cpu_clock_sample_group(clkid, p, !sigev_none);
/* Retrieve the previous expiry value if requested. */
if (old) {
old->it_value = (struct timespec64){ };
if (old_expires)
- __posix_cpu_timer_get(timer, old, val);
+ __posix_cpu_timer_get(timer, old, now);
}
if (unlikely(ret)) {
@@ -706,7 +702,7 @@ static int posix_cpu_timer_set(struct k_
/* Convert relative expiry time to absolute */
if (new_expires && !(timer_flags & TIMER_ABSTIME))
- new_expires += val;
+ new_expires += now;
/* Set the new expiry time (might be 0) */
cpu_timer_setexpires(ctmr, new_expires);
@@ -716,7 +712,7 @@ static int posix_cpu_timer_set(struct k_
* not yet expired and the timer requires signal delivery.
* SIGEV_NONE timers are never armed.
*/
- if (!sigev_none && new_expires && val < new_expires)
+ if (!sigev_none && new_expires && now < new_expires)
arm_timer(timer, p);
unlock_task_sighand(p, &flags);
@@ -736,7 +732,7 @@ static int posix_cpu_timer_set(struct k_
timer->it_overrun_last = 0;
timer->it_overrun = -1;
- if (!sigev_none && val >= new_expires) {
+ if (!sigev_none && now >= new_expires) {
if (new_expires != 0) {
/*
* The designated time already passed, so we notify
next prev parent reply other threads:[~2024-04-10 22:46 UTC|newest]
Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-10 22:46 [patch V2 00/50] posix-timers: Cure inconsistencies and the SIG_IGN mess Thomas Gleixner
2024-04-10 22:46 ` [patch V2 01/50] selftests/timers/posix_timers: Simplify error handling Thomas Gleixner
2024-04-12 7:35 ` Anna-Maria Behnsen
2024-04-10 22:46 ` [patch V2 02/50] selftests/timers/posix_timers: Add SIG_IGN test Thomas Gleixner
2024-04-10 22:46 ` [patch V2 03/50] selftests/timers/posix_timers: Validate signal rules Thomas Gleixner
2024-04-10 22:46 ` [patch V2 04/50] selftests/timers/posix-timers: Validate SIGEV_NONE Thomas Gleixner
2024-04-10 22:46 ` [patch V2 05/50] selftests/timers/posix-timers: Validate timer_gettime() Thomas Gleixner
2024-04-10 22:46 ` [patch V2 06/50] selftests/timers/posix-timers: Validate overrun after unblock Thomas Gleixner
2024-04-10 22:46 ` [patch V2 07/50] posix-cpu-timers: Split up posix_cpu_timer_get() Thomas Gleixner
2024-04-12 7:35 ` Anna-Maria Behnsen
2024-04-12 18:25 ` Eric W. Biederman
2024-04-12 19:48 ` Thomas Gleixner
2024-04-16 14:44 ` Oleg Nesterov
2024-04-17 9:21 ` Anna-Maria Behnsen
2024-04-17 11:08 ` Oleg Nesterov
2024-04-17 20:33 ` Frederic Weisbecker
2024-04-10 22:46 ` [patch V2 08/50] posix-cpu-timers: Save interval only for armed timers Thomas Gleixner
2024-04-11 14:25 ` Anna-Maria Behnsen
2024-04-11 22:00 ` Thomas Gleixner
2024-04-10 22:46 ` [patch V2 09/50] posix-cpu-timers: Handle interval timers correctly in timer_get() Thomas Gleixner
2024-04-17 22:50 ` Frederic Weisbecker
2024-04-10 22:46 ` [patch V2 10/50] posix-cpu-timers: Handle SIGEV_NONE " Thomas Gleixner
2024-04-12 18:40 ` Eric W. Biederman
2024-04-12 19:49 ` Thomas Gleixner
2024-04-10 22:46 ` [patch V2 11/50] posix-cpu-timers: Handle SIGEV_NONE timers correctly in timer_set() Thomas Gleixner
2024-04-11 15:48 ` Anna-Maria Behnsen
2024-04-11 22:02 ` Thomas Gleixner
2024-04-17 23:04 ` Frederic Weisbecker
2024-04-10 22:46 ` [patch V2 12/50] posix-cpu-timers: Replace old expiry retrieval in posix_cpu_timer_set() Thomas Gleixner
2024-04-15 14:03 ` Anna-Maria Behnsen
2024-04-10 22:46 ` [patch V2 13/50] posix-cpu-timers: Do not arm SIGEV_NONE timers Thomas Gleixner
2024-04-15 14:03 ` Anna-Maria Behnsen
2024-04-10 22:46 ` Thomas Gleixner [this message]
2024-04-10 22:46 ` [patch V2 15/50] posix-cpu-timers: Remove incorrect comment in posix_cpu_timer_set() Thomas Gleixner
2024-04-10 22:46 ` [patch V2 16/50] posix-cpu-timers: Simplify posix_cpu_timer_set() Thomas Gleixner
2024-04-15 15:28 ` Anna-Maria Behnsen
2024-04-10 22:46 ` [patch V2 17/50] posix-timers: Retrieve interval in common timer_settime() code Thomas Gleixner
2024-04-15 15:43 ` Anna-Maria Behnsen
2024-04-10 22:46 ` [patch V2 18/50] posix-timers: Clear overrun in common_timer_set() Thomas Gleixner
2024-04-10 22:46 ` [patch V2 19/50] posix-timers: Convert timer list to hlist Thomas Gleixner
2024-04-10 22:46 ` [patch V2 20/50] posix-timers: Consolidate timer setup Thomas Gleixner
2024-04-16 16:12 ` Anna-Maria Behnsen
2024-04-23 19:38 ` Thomas Gleixner
2024-04-10 22:46 ` [patch V2 21/50] posix-cpu-timers: Make k_itimer::it_active consistent Thomas Gleixner
2024-04-17 10:11 ` Anna-Maria Behnsen
2024-04-10 22:46 ` [patch V2 22/50] posix-timers: Consolidate signal queueing Thomas Gleixner
2024-04-10 22:46 ` [patch V2 23/50] signal: Remove task argument from dequeue_signal() Thomas Gleixner
2024-04-18 14:18 ` Oleg Nesterov
2024-04-10 22:46 ` [patch V2 24/50] signal: Replace BUG_ON()s Thomas Gleixner
2024-04-18 14:37 ` Oleg Nesterov
2024-04-10 22:46 ` [patch V2 25/50] signal: Confine POSIX_TIMERS properly Thomas Gleixner
2024-04-17 12:09 ` Anna-Maria Behnsen
2024-04-18 15:23 ` Oleg Nesterov
2024-04-19 5:42 ` Thomas Gleixner
2024-04-10 22:46 ` [patch V2 26/50] signal: Get rid of resched_timer logic Thomas Gleixner
2024-04-18 16:38 ` Oleg Nesterov
2024-04-18 18:18 ` Oleg Nesterov
2024-04-19 11:06 ` Oleg Nesterov
2024-04-23 21:18 ` Thomas Gleixner
2024-04-24 1:48 ` Thomas Gleixner
2024-04-25 7:22 ` Andrei Vagin
2024-04-10 22:46 ` [patch V2 27/50] posix-timers: Cure si_sys_private race Thomas Gleixner
2024-04-10 22:47 ` [patch V2 28/50] signal: Allow POSIX timer signals to be dropped Thomas Gleixner
2024-04-10 22:47 ` [patch V2 29/50] posix-timers: Drop signal if timer has been deleted or reprogrammed Thomas Gleixner
2024-04-10 22:47 ` [patch V2 30/50] posix-timers: Rename k_itimer::it_requeue_pending Thomas Gleixner
2024-04-10 22:47 ` [patch V2 31/50] posix-timers: Add proper state tracking Thomas Gleixner
2024-04-17 13:40 ` Anna-Maria Behnsen
2024-04-10 22:47 ` [patch V2 32/50] posix-timers: Make signal delivery consistent Thomas Gleixner
2024-04-18 10:29 ` Anna-Maria Behnsen
2024-04-10 22:47 ` [patch V2 33/50] posix-timers: Make signal overrun accounting sensible Thomas Gleixner
2024-04-10 22:47 ` [patch V2 34/50] posix-cpu-timers: Use dedicated flag for CPU timer nanosleep Thomas Gleixner
2024-04-10 22:47 ` [patch V2 35/50] posix-timers: Add a refcount to struct k_itimer Thomas Gleixner
2024-04-10 22:47 ` [patch V2 36/50] signal: Split up __sigqueue_alloc() Thomas Gleixner
2024-04-10 22:47 ` [patch V2 37/50] signal: Provide posixtimer_sigqueue_init() Thomas Gleixner
2024-04-10 22:47 ` [patch V2 38/50] signal: Add sys_private_ptr to siginfo::_sifields::_timer Thomas Gleixner
2024-04-10 22:47 ` [patch V2 39/50] posix-timers: Store PID type in the timer Thomas Gleixner
2024-04-10 22:47 ` [patch V2 40/50] signal: Refactor send_sigqueue() Thomas Gleixner
2024-04-10 22:47 ` [patch V2 41/50] posix-timers: Embed sigqueue in struct k_itimer Thomas Gleixner
2024-04-10 22:47 ` [patch V2 42/50] signal: Cleanup unused posix-timer leftovers Thomas Gleixner
2024-04-10 22:47 ` [patch V2 43/50] signal: Add task argument to flush_sigqueue_mask() Thomas Gleixner
2024-04-10 22:47 ` [patch V2 44/50] signal: Provide ignored_posix_timers list Thomas Gleixner
2024-04-10 22:47 ` [patch V2 45/50] posix-timers: Handle ignored list on delete and exit Thomas Gleixner
2024-04-10 22:47 ` [patch V2 46/50] signal: Handle ignored signals in do_sigaction(action != SIG_IGN) Thomas Gleixner
2024-04-10 22:47 ` [patch V2 47/50] signal: Queue ignored posixtimers on ignore list Thomas Gleixner
2024-04-10 22:47 ` [patch V2 48/50] posix-timers: Cleanup SIG_IGN workaround leftovers Thomas Gleixner
2024-04-10 22:47 ` [patch V2 49/50] alarmtimers: Remove the throttle mechanism from alarm_forward_now() Thomas Gleixner
2024-04-10 22:47 ` [patch V2 50/50] alarmtimers: Remove return value from alarm functions Thomas Gleixner
2024-04-15 12:30 ` [PATCH] posix-timers: Handle returned errors poperly in [i]timer_delete() Anna-Maria Behnsen
2024-04-15 13:00 ` Oleg Nesterov
2024-04-15 14:15 ` Anna-Maria Behnsen
2024-04-15 16:27 ` Oleg Nesterov
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