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Date: Thu, 07 Feb 2002 11:59:19 -0800
From: Andrew Morton <akpm@zip.com.au>
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CC: Robert Love <rml@tech9.net>, Martin Wirth <Martin.Wirth@dlr.de>,
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Subject: Re: [RFC] New locking primitive for 2.5
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Ingo Molnar wrote:
> 
> On Thu, 7 Feb 2002, Andrew Morton wrote:
> 
> > Quite a few.  Significant ones.  pagemap_lru_lock and lru_list_lock
> > come to mind.
> 
> ugh. Are you sure we want to *sleep* with something like pagemap_lru_lock
> held?

Not guilty :)  I was answering rml's question.

I suspect lru_list_lock is the shining example.  We often
take it for very short periods and occasionally take it
for enormous periods.

> That pretty much brings all pagecache related operations to a
> grinding halt.

yup.  We'd go into a sheduling storm until we find the process
which holds the lock.

> I think complex spinlocked sections should be simplified
> rather.

yes.

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