Re: [PATCH] Profile likely/unlikely macros

From: Mikael Pettersson
Date: Tue Apr 25 2006 - 05:15:42 EST


On Mon, 24 Apr 2006 19:57:47 -0700, Daniel Walker wrote:
>+ if (likeliness->type & LIKELY_UNSEEN) {
>+ if (atomic_dec_and_test(&likely_lock)) {
>+ if (likeliness->type & LIKELY_UNSEEN) {
>+ likeliness->type &= (~LIKELY_UNSEEN);
>+ likeliness->next = likeliness_head;
>+ likeliness_head = likeliness;
>+ }
>+ }
>+ atomic_inc(&likely_lock);
>+ }

I'm pretty sure one can do this (prepending an element to a list)
w/o fiddling with locks by using CAS and looping until successful.

/Mikael
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