On Thu, Jan 24, 2019 at 09:14:37PM +0300, Cyrill Gorcunov wrote:
> The rcu_qs is disabling IRQs by self so no need to do the same in
> raise_softirq
> but instead we can save some cycles using raise_softirq_irqoff directly.
>
> CC: Paul E. McKenney <[email protected]>
> Signed-off-by: Cyrill Gorcunov <[email protected]>
Good eyes, good combo optimization of both space and time, thank you!!!
Queued, most likely for v5.2.
Thanx, Paul
> ---
> The prev patch body has been screwed, sorry.
>
> kernel/rcu/tiny.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> Index: linux-next.git/kernel/rcu/tiny.c
> ===================================================================
> --- linux-next.git.orig/kernel/rcu/tiny.c
> +++ linux-next.git/kernel/rcu/tiny.c
> @@ -65,7 +65,7 @@ void rcu_qs(void)
> local_irq_save(flags);
> if (rcu_ctrlblk.donetail != rcu_ctrlblk.curtail) {
> rcu_ctrlblk.donetail = rcu_ctrlblk.curtail;
> - raise_softirq(RCU_SOFTIRQ);
> + raise_softirq_irqoff(RCU_SOFTIRQ);
> }
> local_irq_restore(flags);
> }
>
