Messages in this thread | | | Date | Tue, 22 Sep 2015 12:28:45 -0700 | Subject | Re: [PATCH v2] netlink: Replace rhash_portid with bound | From | Linus Torvalds <> |
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On Tue, Sep 22, 2015 at 11:53 AM, Tejun Heo <tj@kernel.org> wrote: > > I see. The write path here is cold so the competition is between rmb > and acquire. Unless some significant archs completely screwed it up, > acquire still seems like the better option. It's essentially free on > x86 after all.
Both acquire and smp_rmb() are equally free on x86.
It appears that we don't do the X86_PPRO_FENCE bug handling for acquire, but I guess we should.
Or possibly we should start deprecating the insane X86_PPRO_FENCE entirely. It's very costly, for dubious advantages.
Linus
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