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Date:   Mon, 24 Jul 2023 09:27:54 -0400
From:   Chuck Lever <chuck.lever@oracle.com>
To:     David Howells <dhowells@redhat.com>
Cc:     Chuck Lever <cel@kernel.org>, linux-nfs@vger.kernel.org,
        netdev@vger.kernel.org
Subject: Re: [PATCH v3 2/5] SUNRPC: Send RPC message on TCP with a single
 sock_sendmsg() call
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On Mon, Jul 24, 2023 at 10:58:50AM +0100, David Howells wrote:
> Chuck Lever <cel@kernel.org> wrote:
> 
> > +	buf = page_frag_alloc(&svsk->sk_frag_cache, sizeof(marker),
> > +			      GFP_KERNEL);
> 
> Is this SMP-safe?  page_frag_alloc() does no locking.

Note that svc_tcp_sendto() takes xprt->xpt_mutex. There can be only
one thread (per svsk) running in svc_tcp_sendmsg() at a time.


-- 
Chuck Lever