Messages in this thread | | | Date | Wed, 25 Nov 2015 16:46:07 +0100 | From | Michal Hocko <> | Subject | Re: [PATCH v2 3/9] mm, page_owner: convert page_owner_inited to static key |
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On Wed 25-11-15 16:25:33, Peter Zijlstra wrote: > On Wed, Nov 25, 2015 at 04:08:11PM +0100, Vlastimil Babka wrote: > > Now I admit I have no idea if there are architectures that don't support jump > > labels *and* have an expensive atomic read, and whether we care? > > atomic_read() is basically always READ_ONCE(), there's a few archs that > implement it in asm with a 'weird' load instruction, but its still a > load. The worst is I think an uncached load for blackfin or somesuch. > > There's plenty archs that do not support the jump label bits, but > typically you don't care much about those. I'm not aware of an arch that > cannot fundamentally implement jump_label support if they wanted to.
OK, I see. Thanks for the clarification! Then I do not have any objections.
-- Michal Hocko SUSE Labs
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