On Thu, 15 Nov 2007 04:01:48 GMT Linux Kernel Mailing List <linux-kernel@vger.kernel.org> wrote:
> Gitweb: > http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=d90bf5a976793edfa88d3bb2393f0231eb8ce1e5 > Commit: d90bf5a976793edfa88d3bb2393f0231eb8ce1e5 Parent: > 66ba886254edbbd9442d30f1eef6f6fb0145027d Author: Eric Dumazet > <[EMAIL PROTECTED]> AuthorDate: Wed Nov 14 16:14:05 2007 -0800 > Committer: David S. Miller <[EMAIL PROTECTED]> > CommitDate: Wed Nov 14 16:14:05 2007 -0800 > > [NET]: rt_check_expire() can take a long time, add a > cond_resched() > On commit 39c90ece7565f5c47110c2fa77409d7a9478bd5b: > When the IP route cache is big, rt_check_expire() can take a long > time to run. (default settings : 20% of the hash table is scanned at > each invocation) > > Adding cond_resched() helps giving cpu to higher priority tasks if > necessary. > > Using a "if (need_resched())" test before calling > "cond_resched();" is necessary to avoid spending too much time doing > the resched check. int __sched cond_resched(void) { if (need_resched() && ..... somehow I wonder why the second if() is useful at all; it's another spot for a branch predictor to miss... and a void function call is really really cheap... -- If you want to reach me at my work email, use [EMAIL PROTECTED] For development, discussion and tips for power savings, visit http://www.lesswatts.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
