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Date:   Mon, 10 Oct 2022 23:18:19 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Guillaume Nault <gnault@redhat.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna@kernel.org>,
        Chuck Lever <chuck.lever@oracle.com>,
        Jeff Layton <jlayton@kernel.org>, linux-nfs@vger.kernel.org,
        Paolo Abeni <pabeni@redhat.com>,
        Benjamin Coddington <bcodding@redhat.com>
Subject: Re: [PATCH v2] sunrpc: Use GFP_NOFS to prevent use of
 current->task_frag.
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References: <de6d99321d1dcaa2ad456b92b3680aa77c07a747.1665401788.git.gnault@redhat.com>
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On Mon, Oct 10, 2022 at 06:56:50PM +0200, Guillaume Nault wrote:
> That's what my RFC patch did. It was rejected because reading
> current->flags may incur a cache miss thus slowing down TCP fast path.
> See the discussion in the Link tag:
> https://lore.kernel.org/netdev/b4d8cb09c913d3e34f853736f3f5628abfd7f4b6.1656699567.git.gnault@redhat.com/

As GFP_NOFS/NOIO are on their way out the networking people will have to
do this anyway.