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Date:   Tue, 21 Dec 2021 00:41:29 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     NeilBrown <neilb@suse.de>
Cc:     Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna.schumaker@netapp.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mel Gorman <mgorman@suse.de>,
        Christoph Hellwig <hch@infradead.org>,
        David Howells <dhowells@redhat.com>, linux-nfs@vger.kernel.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 04/18] MM: perform async writes to SWP_FS_OPS swap-space
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 <163969850292.20885.16191050558510542930.stgit@noble.brown>
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On Fri, Dec 17, 2021 at 10:48:22AM +1100, NeilBrown wrote:
> Writes to SWP_FS_OPS swapspace is currently synchronous.  To make it
> async we need to allocate the kiocb struct which may block, but won't
> block as long as waiting for the write to complete would block.

Against a little helper for the SWP_FS_OPS case of __swap_writepage
would be nice.  But otherwise this looks good to me.