6.12-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Gleixner tglx@linutronix.de
commit 2ea97b76d6712bfb0408e5b81ffd7bc4551d3153 upstream.
The sanity checks in hrtimer_update_function() are expensive for high frequency usage like in the io/uring code due to locking.
Hide the sanity checks behind CONFIG_PROVE_LOCKING, which has a decent chance to be enabled on a regular basis for testing.
Fixes: 8f02e3563bb5 ("hrtimers: Introduce hrtimer_update_function()") Reported-by: Jens Axboe axboe@kernel.dk Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lore.kernel.org/all/87ikpllali.ffs@tglx Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/hrtimer.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -348,6 +348,7 @@ static inline int hrtimer_callback_runni static inline void hrtimer_update_function(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *)) { +#ifdef CONFIG_PROVE_LOCKING guard(raw_spinlock_irqsave)(&timer->base->cpu_base->lock);
if (WARN_ON_ONCE(hrtimer_is_queued(timer))) @@ -355,7 +356,7 @@ static inline void hrtimer_update_functi
if (WARN_ON_ONCE(!function)) return; - +#endif timer->function = function; }