From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753441AbaGNGRG (ORCPT ); Mon, 14 Jul 2014 02:17:06 -0400 Received: from cantor2.suse.de ([195.135.220.15]:55251 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753406AbaGNGQ5 (ORCPT ); Mon, 14 Jul 2014 02:16:57 -0400 Message-ID: <53C375D7.5080608@suse.de> Date: Mon, 14 Jul 2014 08:16:55 +0200 From: Hannes Reinecke User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: "K. Y. Srinivasan" , jasowang@redhat.com, apw@canonical.com, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, jbottomley@parallels.com, hch@infradead.org, linux-scsi@vger.kernel.org CC: stable@vger.kernel.org Subject: Re: [PATCH 5/7] Drivers: scsi: storvsc: Implement a timedout handler References: <1405183684-23928-1-git-send-email-kys@microsoft.com> <1405183712-23967-1-git-send-email-kys@microsoft.com> <1405183712-23967-5-git-send-email-kys@microsoft.com> In-Reply-To: <1405183712-23967-5-git-send-email-kys@microsoft.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/12/2014 06:48 PM, K. Y. Srinivasan wrote: > On Azure, we have seen instances of unbounded I/O latencies. To deal with > this issue, implement handler that can reset the timeout. Note that the > host gaurantees that it will respond to each command that has been issued. > > > Signed-off-by: K. Y. Srinivasan > Cc: > --- > drivers/scsi/storvsc_drv.c | 10 ++++++++++ > 1 files changed, 10 insertions(+), 0 deletions(-) > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > index 7e8a642..3516761 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -33,6 +33,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -1518,6 +1519,14 @@ static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) > return SUCCESS; > } > > +static enum blk_eh_timer_return storvsc_timeout_handler(struct scsi_cmnd *scmnd) > +{ > + /* > + * The host will respond; ask for more time. > + */ > + return BLK_EH_RESET_TIMER; > +} > + > static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd) > { > bool allowed = true; > @@ -1697,6 +1706,7 @@ static struct scsi_host_template scsi_driver = { > .bios_param = storvsc_get_chs, > .queuecommand = storvsc_queuecommand, > .eh_host_reset_handler = storvsc_host_reset_handler, > + .eh_timed_out = storvsc_timeout_handler, > .slave_alloc = storvsc_device_alloc, > .slave_destroy = storvsc_device_destroy, > .slave_configure = storvsc_device_configure, > Reviewed-by: Hannes Reinecke Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)