Re: [PATCH] timers: Recalculate next timer interrupt only when necessary

Thomas Gleixner
2020-07-23T13:53:36Z

Frederic Weisbecker <frederic@kernel.org> writes:
>
> Since recalculating the next_expiry isn't a free operation, especially
> when we must climb up the last wheel level to find out that no timer
> has

I'm climbing stairs or mountains :)

> been enqueued at all, lets reuse the next expiry cache when it is
> known

lets? Come on, the changelog is about facts not what we might do.

> unsigned long clk;
> unsigned long next_expiry;
> + bool next_expiry_recalc;
> unsigned int cpu;
> bool is_idle;

Care to stare at the output of

pahole -C timer_base kernel/time/timer.o

before and after?

Thanks,

tglx