Messages in this thread | | | Date | Tue, 5 Jan 2010 19:00:26 +0100 | From | Andi Kleen <> | Subject | Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() |
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On Tue, Jan 05, 2010 at 11:47:49AM -0600, Christoph Lameter wrote: > On Tue, 5 Jan 2010, Andi Kleen wrote: > > > > Oh well. Somebody who is bored might look at trying to make the wrapper > > > code in arch/x86/lib/semaphore_32.S work on x86-64 too. It should make the > > > successful rwsem cases much faster. > > > > Maybe, maybe not. > > What we saw in the past was that the cost of acquiring exclusive > access to the contended cachelines containing mmap_sem and rss counters > was most important.
That cost should be about the same between the spinlock and the atomic version.
-Andi
-- ak@linux.intel.com -- Speaking for myself only.
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