Messages in this thread | | | Date | Tue, 29 Apr 2008 10:50:30 -0500 | From | Robin Holt <> | Subject | Re: [PATCH 01 of 12] Core of mmu notifiers |
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> I however doubt this will bring us back to the same performance of the > current spinlock version, as the real overhead should come out of > overscheduling in down_write ai anon_vma_link. Here an initially > spinning lock would help but that's gray area, it greatly depends on > timings, and on very large systems where a cacheline wait with many > cpus forking at the same time takes more than scheduling a semaphore > may not slowdown performance that much. So I think the only way is a > configuration option to switch the locking at compile time, then XPMEM > will depend on that option to be on, I don't see a big deal and this > guarantees embedded isn't screwed up by totally unnecessary locks on UP.
You have said this continually about a CONFIG option. I am unsure how that could be achieved. Could you provide a patch?
Thanks, Robin
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