From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Splice on blocking TCP sockets again..
Date: Wed, 30 Sep 2009 07:51:21 +0200
Message-ID: <4AC2F1D9.1010801@gmail.com>
References: <20090930004820.GC19540@obsidianresearch.com> <4AC2E481.5060509@gmail.com> <20090930054031.GY22310@obsidianresearch.com>
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Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	Volker Lendecke <vl@samba.org>
To: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
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Jason Gunthorpe a =E9crit :
>> One way to handle this is to switch tcp_read() to use the underlying=
 file O_NONBLOCK
>> flag, as other socket operations do. And let SPLICE_F_NONBLOCK contr=
ol the pipe output only.

arg, this was tcp_splice_read() of course

>=20
> Thanks Eric, this seems reasonable from my userspace perspective.
>=20
> I admit I don't understand why SPLICE_F_NONBLOCK exists, it seems ver=
y
> un-unixy to have a syscall completely ignore the NONBLOCK flag of the
> fd it is called on. Ie setting NONBLOCK on the pipe itself does
> nothing when using splice..
>=20

Hmm, good question, I dont have the answer but I'll digg one.