From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: Re: [PATCH net] e1000e: Change wthresh to 1 to avoid possible Tx stalls. Date: Wed, 06 Jun 2012 17:59:12 -0700 Message-ID: <1339030752.2075.1.camel@jtkirshe-mobl> References: <20120606174355.823e9aa7.shimoda.hiroaki@gmail.com> Reply-To: jeffrey.t.kirsher@intel.com Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-5Eago++T/3nQdiSzbE2Y" Cc: "davem@davemloft.net" , "denys@visp.net.lb" , "eric.dumazet@gmail.com" , "therbert@google.com" , "netdev@vger.kernel.org" To: Hiroaki SHIMODA , Eric Dumazet Return-path: Received: from mga01.intel.com ([192.55.52.88]:12957 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752217Ab2FGA7N (ORCPT ); Wed, 6 Jun 2012 20:59:13 -0400 In-Reply-To: <20120606174355.823e9aa7.shimoda.hiroaki@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: --=-5Eago++T/3nQdiSzbE2Y Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2012-06-06 at 01:43 -0700, Hiroaki SHIMODA wrote: > Denys Fedoryshchenko reported Tx stalls on e1000e with BQL enabled. >=20 > e1000e has WTHRESH which determines when Tx descripters are written > back and successive Tx interrupts are generated, and setting WTHRESH > to 5 gives efficient bus utilization but this cause possible Tx > stalls, > especially on BQL enabled system. >=20 > To avoid possible Tx stalls, change WTHRESH to 1. >=20 > Reported-by: Denys Fedoryshchenko > Tested-by: Denys Fedoryshchenko > Signed-off-by: Hiroaki SHIMODA > --- > drivers/net/ethernet/intel/e1000e/e1000.h | 6 +++--- > drivers/net/ethernet/intel/e1000e/netdev.c | 2 +- > 2 files changed, 4 insertions(+), 4 deletions(-)=20 After further internal review, NACK. This patch will cause unacceptable performance issues with non-ESB2 parts. I am dropping this patch from my queue. --=-5Eago++T/3nQdiSzbE2Y Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAABCgAGBQJPz/zgAAoJEOVv75VaS+3O/K4QAJGY6ZJvGWex3xEx3Kxx7GMY J/eyGv8kjFE5TZClvfT3YP9Q9WVm/cI9dD5O8W7Mm0HQHYDm7H5ZChZYFbfAGW4R +keUqAm1qUY8NrhSSspnEOePlgLKGCrT5CrkfCoa+rGwNkSP1145ecXQzij3yEGg ffwUbMtelKDIgcd8OB11IpmmeQc5MAxSFQCECHe9lY/lv5mywqcsaW7EoKLrhK+e 9WAbv/NkS3hJi8EGQIgZ+DmL7e648XxIFuA+jsZG4eBBNJYKFOosRGWfaA5vqMjB pluKKjB9zKBs3eWMIdHZ++7ZLEucijT/4p0PeLV8EQJTNvfHnqnJc8PIrEM4+a+d AXNwz8vDaREwtnsl2V4U21qEMeKpLb9dVDOqWnr2JzLBzPaB7PmVFTqCjgIUUa8z oaAm4EwV8yn4cWtlP03vUl0vYtmfM0YR5r4/nmtzuVmeow54TMdDvSXGTQcl+KTh dY7vQ71XV5ulk85pnyfMQ7Sqj4+XfJh/u2SPu8Zm5gDjCQk96SdaCN4N7h813tsE 4YzVBzGEXrf9spNmFCtW3yZGHCuE6yOqHwcF+mPQtfgfO5AI/esACzh3meRmlJ88 0oF8phzo+w4XQ5/WGMBti1bmVwSHtmj+dvNlvSy9l6R4eO0GAMSES3soGhwUK7SL rr92W3ZUjr3o9+2cscs+ =VXwn -----END PGP SIGNATURE----- --=-5Eago++T/3nQdiSzbE2Y--