On Tue, Jun 10, 2003 at 06:23:38PM -0700, David S. Miller wrote: > From: Ralph Doncaster <ralph@istop.com> > Date: Tue, 10 Jun 2003 21:17:28 -0400 (EDT) > > Aren't the read_lock_irqsave and restore expensive? > > If x86 has an inefficient implementation, well... :-) sti/cli is normally fast on x86, a bit slower on P3 core (a few cycles or so) read_lock_irqsave does a pushfl though, that's rather slow on P4, but still not that bad. read_lock_irq would be faster, but too risky here. > > This can be done without locks, nobody has done the x86 implementation > of that that's all. I think the x86_64 folks did a lockless version, > I know I did for sparc64 :) 2.5 i386 gettimeofday is lockless. But on UP it should not make any difference anyways. -Andi - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
