Messages in this thread | | | Date | Fri, 27 Sep 2013 08:02:13 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH v6 5/6] MCS Lock: Restructure the MCS lock defines and locking code into its own file |
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* Tim Chen <tim.c.chen@linux.intel.com> wrote:
> > If we prefer to optimize this a bit though, perhaps we can first move > > the node->lock = 0 so that it gets executed after the "if (likely(prev > > == NULL)) {}" code block and then delete "node->lock = 1" inside the > > code block. > > I suppose we can save one single assignment. The gain is probably not > noticeable as once we set node->next to NULL, node->locked is likely in > local cache line and the assignment operation is cheap.
Would be nice to have this as a separate, add-on patch. Every single instruction removal that has no downside is an upside!
You can add a comment that explains it.
Thanks,
Ingo
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