Messages in this thread | | | From | Nick Piggin <> | Subject | Re: [PATCH 0/4] futex: get_user_pages_fast() for shared futexes | Date | Tue, 30 Sep 2008 17:21:51 +1000 |
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On Sunday 28 September 2008 02:17, Ingo Molnar wrote: > * Peter Zijlstra <a.p.zijlstra@chello.nl> wrote: > > Since get_user_pages_fast() made it in, I thought to give this another > > try. Lightly tested by disabling the private futexes and running some > > java proglets. > > hm, very interesting. Since this is an important futex usecase i started > testing it in tip/core/futexes: > > cd33272: futex: cleanup fshared > a135356: futex: use fast_gup() > 39ce77b: futex: reduce mmap_sem usage > 0d7a336: futex: rely on get_user_pages() for shared futexes > > Nick, it would be nice to get an Acked-by/Reviewed-by from you, before > we think about whether it should go upstream.
Yeah, these all look pretty good. It's nice to get rid of mmap sem here.
Which reminds me, we need to put a might_lock mmap_sem into get_user_pages_fast...
But these patches look good to me (last time we discussed them I thought there was a race with page truncate, but it looks like you've closed that by holding page lock over the whole operation...)
Nice work, Peter.
BTW. what kinds of things use inter-process futexes as of now?
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