From: Thomas Gleixner <tglx@linutronix.de>
To: Mike Galbraith <efault@gmx.de>,
linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>,
x86@kernel.org, Marek Szyprowski <m.szyprowski@samsung.com>
Subject: [PATCH] hrtimer: Use raw_cpu_ptr() in clock_was_set()
Date: Thu, 12 Aug 2021 22:31:24 +0200 [thread overview]
Message-ID: <875ywacsmb.ffs@tglx> (raw)
In-Reply-To: <87a6lmiwi0.ffs@tglx>
clock_was_set() can be invoked from preemptible context. Use raw_cpu_ptr()
to check whether high resolution mode is active or not. It does not matter
whether the task migrates after acquiring the pointer.
Fixes: e71a4153b7c2 ("hrtimer: Force clock_was_set() handling for the HIGHRES=n, NOHZ=y case")
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
kernel/time/hrtimer.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -944,10 +944,11 @@ static bool update_needs_ipi(struct hrti
*/
void clock_was_set(unsigned int bases)
{
+ struct hrtimer_cpu_base *cpu_base = raw_cpu_ptr(&hrtimer_bases);
cpumask_var_t mask;
int cpu;
- if (!hrtimer_hres_active() && !tick_nohz_active)
+ if (!__hrtimer_hres_active(cpu_base) && !tick_nohz_active)
goto out_timerfd;
if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) {
@@ -958,9 +959,9 @@ void clock_was_set(unsigned int bases)
/* Avoid interrupting CPUs if possible */
cpus_read_lock();
for_each_online_cpu(cpu) {
- struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
unsigned long flags;
+ cpu_base = &per_cpu(hrtimer_bases, cpu);
raw_spin_lock_irqsave(&cpu_base->lock, flags);
if (update_needs_ipi(cpu_base, bases))
next prev parent reply other threads:[~2021-08-12 20:31 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-13 13:39 [patch V2 00/10] hrtimer: Reprogramming and clock_was_set() overhaul Thomas Gleixner
2021-07-13 13:39 ` [patch V2 01/10] hrtimer: Avoid double reprogramming in __hrtimer_start_range_ns() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 02/10] hrtimer: Consolidate reprogramming code Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Peter Zijlstra
2021-08-12 7:19 ` Mike Galbraith
2021-08-12 14:11 ` Thomas Gleixner
2021-08-12 14:32 ` Thomas Gleixner
2021-08-12 15:04 ` Mike Galbraith
2021-08-12 15:22 ` Thomas Gleixner
2021-08-12 15:31 ` Mike Galbraith
2021-08-12 16:58 ` Thomas Gleixner
2021-08-12 15:27 ` Mike Galbraith
2021-08-12 20:32 ` [PATCH] hrtimer: Unbreak hrtimer_force_reprogram() Thomas Gleixner
2021-08-12 20:40 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-08-13 7:58 ` [PATCH] " Thomas Gleixner
2021-08-12 20:31 ` Thomas Gleixner [this message]
2021-08-12 20:40 ` [tip: timers/core] hrtimer: Use raw_cpu_ptr() in clock_was_set() tip-bot2 for Thomas Gleixner
2021-08-13 6:42 ` [PATCH] " Marek Szyprowski
2021-08-12 13:09 ` [patch V2 02/10] hrtimer: Consolidate reprogramming code Marek Szyprowski
2021-07-13 13:39 ` [patch V2 03/10] hrtimer: Ensure timerfd notification for HIGHRES=n Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 04/10] hrtimer: Force clock_was_set() handling for the HIGHRES=n, NOHZ=y case Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 05/10] timerfd: Provide timerfd_resume() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 06/10] timekeeping: Distangle resume and clock-was-set events Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 07/10] time/timekeeping: Avoid invoking clock_was_set() twice Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 08/10] hrtimer: Add bases argument to clock_was_set() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
2021-07-13 13:39 ` [patch V2 09/10] hrtimer: Avoid unnecessary SMP function calls in clock_was_set() Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Marcelo Tosatti
2021-07-13 13:39 ` [patch V2 10/10] hrtimer: Avoid more " Thomas Gleixner
2021-08-10 16:02 ` [tip: timers/core] " tip-bot2 for Thomas Gleixner
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