Messages in this thread | | | Subject | Re: [patch]block: fix ioc locking warning | From | Shaohua Li <> | Date | Tue, 07 Feb 2012 09:10:20 +0800 |
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On Mon, 2012-02-06 at 16:59 -0800, Tejun Heo wrote: > On Tue, Feb 07, 2012 at 08:43:50AM +0800, Shaohua Li wrote: > > Quite simple, copy kernel source to tmpfs in tight memory environment. > > This will trigger swap. The bisection result appears stable. > > Looked through the commit again but it really doesn't change fast > paths. The only paths which can be slower are ioc and q exits. Can > you please do the followings? > > * Share the script used for microbench. Maybe it somehow exposes > slower exit path? How much regression are we talking about? I need strip the script out from our test framework, but it essentially is a 'time copy -a tmpfs/kernelsource tmpfs/copy'. The time increased ~20% with 3.3-rc1.
> * Test with the this_q != locked_q trylock patch. sure.
Thanks, Shaohua
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