Date: Wed, 21 Dec 2016 09:09:31 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>,
        Bob Peterson <rpeterso@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Andrew Lutomirski <luto@kernel.org>,
        Andreas Gruenbacher <agruenba@redhat.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        linux-mm <linux-mm@kvack.org>
Subject: Re: [RFC][PATCH] make global bitlock waitqueues per-node
Message-ID: <20161221080931.GQ3124@twins.programming.kicks-ass.net>
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On Tue, Dec 20, 2016 at 10:02:46AM -0800, Linus Torvalds wrote:
> On Tue, Dec 20, 2016 at 9:31 AM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > I'll go back and try to see why the page flag contention patch didn't
> > get applied.
> 
> Ahh, a combination of warring patches by Nick and PeterZ, and worry
> about the page flag bits.

I think Nick actually had a patch freeing up a pageflag, although Hugh
had a comment on that.

That said, I'm not a huge fan of his waiters patch, I'm still not sure
why he wants to write another whole wait loop, but whatever. Whichever
you prefer I suppose.