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Date:   Mon, 30 Aug 2021 10:12:08 +0100
From:   Mel Gorman <mgorman@suse.com>
To:     NeilBrown <neilb@suse.de>
Cc:     Chuck Lever III <chuck.lever@oracle.com>,
        Mike Javorski <mike.javorski@gmail.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH] SUNRPC: don't pause on incomplete allocation
Message-ID: <20210830091208.GB3997@suse.com>
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On Mon, Aug 30, 2021 at 08:36:34AM +1000, NeilBrown wrote:
> 
> alloc_pages_bulk_array() attempts to allocate at least one page based on
> the provided pages, and then opportunistically allocates more if that
> can be done without dropping the spinlock.
> 
> So if it returns fewer than requested, that could just mean that it
> needed to drop the lock.  In that case, try again immediately.
> 
> Only pause for a time if no progress could be made.
> 
> Reported-and-tested-by: Mike Javorski <mike.javorski@gmail.com>
> Reported-and-tested-by: Lothar Paltins <lopa@mailbox.org>
> Fixes: f6e70aab9dfe ("SUNRPC: refresh rq_pages using a bulk page allocator")
> Signed-off-by: NeilBrown <neilb@suse.de>

Acked-by: Mel Gorman <mgorman@suse.com>

-- 
Mel Gorman
SUSE Labs