From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Subject: Re: Splice on blocking TCP sockets again..
Date: Tue, 29 Sep 2009 23:40:31 -0600
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Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	Volker Lendecke <vl@samba.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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> 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 control the pipe output only.

Thanks Eric, this seems reasonable from my userspace perspective.

I admit I don't understand why SPLICE_F_NONBLOCK exists, it seems very
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..

Jason