Messages in this thread | | | Subject | Re: [Patch] x86,pat Update the page flags for memtype atomically instead of using memtype_lock. | From | Suresh Siddha <> | Date | Fri, 12 Mar 2010 17:46:02 -0800 |
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On Fri, 2010-03-12 at 17:08 -0800, Thomas Gleixner wrote: > On Fri, 12 Mar 2010, Suresh Siddha wrote: > > On Thu, 2010-03-11 at 08:17 -0800, Robin Holt wrote: > > > Changes since -V1: > > > 1) Introduce atomically setting and clearing the page flags and not > > > using the global memtype_lock to protect page->flags. > > > > > > 2) This allowed me the opportunity to convert the rwlock back into a > > > spinlock and not affect _MY_ tests performance as all the pages my test > > > was utilizing are tracked by struct pages. > > > > Can you also include this spinlock to rwlock conversion, which can be > > used for non RAM pages as a second patch? > > spinlock -> rwlock conversion ? I hope you meant it the other way > round as Robin said in #2 :)
Thomas, No. I meant converting the existing memtype_lock which is a spinlock into rwlock. Robin has this in the first version of the patch but he dropped it in a later version as he avoided this lock for RAM pages.
Just wanted to make sure that we address the perf aspect even for non RAM pages by converting the memtype_lock into rwlock before some one else reports a similar issue for non RAM pages.
thanks, suresh
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