Message-ID: <1370439054.24311.248.camel@edumazet-glaptop>
Subject: Re: [PATCH v9 net-next 5/7] net: simple poll/select low latency
 socket poll
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David Miller <davem@davemloft.net>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Don Skidmore <donald.c.skidmore@intel.com>,
        e1000-devel@lists.sourceforge.net,
        Willem de Bruijn <willemb@google.com>,
        Ben Hutchings <bhutchings@solarflare.com>,
        Andi Kleen <andi@firstfloor.org>, HPA <hpa@zytor.com>,
        Eilon Greenstien <eilong@broadcom.com>,
        Or Gerlitz <or.gerlitz@gmail.com>, Amir Vadai <amirv@mellanox.com>,
        Eliezer Tamir <eliezer@tamir.org.il>
Date: Wed, 05 Jun 2013 06:30:54 -0700
In-Reply-To: <20130605103452.11172.31453.stgit@ladj378.jer.intel.com>
References: <20130605103400.11172.49099.stgit@ladj378.jer.intel.com>
	 <20130605103452.11172.31453.stgit@ladj378.jer.intel.com>
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On Wed, 2013-06-05 at 13:34 +0300, Eliezer Tamir wrote:
> A very naive select/poll busy-poll support.
> Add busy-polling to sock_poll().
> When poll/select have nothing to report, call the low-level
> sock_poll() again until we are out of time or we find something.
> Right now we poll every socket once, this is suboptimal
> but improves latency when the number of sockets polled is not large.
> 
> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
> Tested-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
> ---

I am a bit uneasy with this one, because an applicatio polling() on one
thousand file descriptors using select()/poll(), will call sk_poll_ll()
one thousand times.


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