From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62CB6C169C4 for ; Thu, 31 Jan 2019 10:25:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 33E91218D9 for ; Thu, 31 Jan 2019 10:25:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731924AbfAaKZe (ORCPT ); Thu, 31 Jan 2019 05:25:34 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:43704 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726434AbfAaKZd (ORCPT ); Thu, 31 Jan 2019 05:25:33 -0500 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 7F30F69E8479B4414E85; Thu, 31 Jan 2019 18:25:31 +0800 (CST) Received: from [127.0.0.1] (10.202.226.43) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.408.0; Thu, 31 Jan 2019 18:25:21 +0800 Subject: Re: [PATCH v2 3/7] scsi: libsas: optimize the debug print of the revalidate process To: Jason Yan , , References: <20190130082412.9357-1-yanaijie@huawei.com> <20190130082412.9357-4-yanaijie@huawei.com> <2ffa6821-93d4-7925-d435-e34338f323ec@huawei.com> <5C524FE2.9070801@huawei.com> CC: , , , , , , , , , , , , Ewan Milne , Tomas Henzl From: John Garry Message-ID: <50358ca3-5350-2f82-b94e-02e27a64873f@huawei.com> Date: Thu, 31 Jan 2019 10:25:11 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <5C524FE2.9070801@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.226.43] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 31/01/2019 01:31, Jason Yan wrote: > > > On 2019/1/31 0:41, John Garry wrote: >> On 30/01/2019 08:24, Jason Yan wrote: >>> sas_rediscover() returns error code if discover failed for a expander >>> phy. And sas_ex_revalidate_domain() only returns the last phy's error >>> code. So when sas_revalidate_domain() prints the return value of the >>> discover process, we do not know if the revalidation for every phy is >>> successful or not. We just know the last bcast phy revalidation >>> succeeded or not. >>> >>> No need to return a error code for sas_ex_revalidate_domain() and >>> sas_rediscover(), and just print the debug log for each bcast phy >>> directly >>> in sas_rediscover(). >> >> do we want to know about every PHY, or just the PHY where res != 0? >> > > Here I mean every PHY that raises bcast. This may be better added at the sas_rediscover() callsite. And do you feel adding this for every bcast phy is useful, or just those whose rediscover error'ed? > >>> >> >> I don't see any optimisation here. Maybe an improvement. >> > > Thanks, I will change the wording. > >> >>> Signed-off-by: Jason Yan >>> CC: John Garry >>> CC: Johannes Thumshirn >>> CC: Ewan Milne >>> CC: Christoph Hellwig >>> CC: Tomas Henzl >>> CC: Dan Williams >>> CC: Hannes Reinecke >>> --- >>> drivers/scsi/libsas/sas_discover.c | 7 +++---- >>> drivers/scsi/libsas/sas_expander.c | 11 ++++++----- >>> include/scsi/libsas.h | 2 +- >>> 3 files changed, 10 insertions(+), 10 deletions(-) >>> >>> diff --git a/drivers/scsi/libsas/sas_discover.c >>> b/drivers/scsi/libsas/sas_discover.c >>> index 726ada9b8c79..ffc571a12916 100644 >>> --- a/drivers/scsi/libsas/sas_discover.c >>> +++ b/drivers/scsi/libsas/sas_discover.c >>> @@ -500,7 +500,6 @@ static void sas_discover_domain(struct work_struct >>> *work) >>> >>> static void sas_revalidate_domain(struct work_struct *work) >>> { >>> - int res = 0; >>> struct sas_discovery_event *ev = to_sas_discovery_event(work); >>> struct asd_sas_port *port = ev->port; >>> struct sas_ha_struct *ha = port->ha; >>> @@ -521,10 +520,10 @@ static void sas_revalidate_domain(struct >>> work_struct *work) >>> >>> if (ddev && (ddev->dev_type == SAS_FANOUT_EXPANDER_DEVICE || >>> ddev->dev_type == SAS_EDGE_EXPANDER_DEVICE)) >>> - res = sas_ex_revalidate_domain(ddev); >>> + sas_ex_revalidate_domain(ddev); >>> >>> - pr_debug("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n", >>> - port->id, task_pid_nr(current), res); >>> + pr_debug("done REVALIDATING DOMAIN on port %d, pid:%d\n", >>> + port->id, task_pid_nr(current)); >>> out: >>> mutex_unlock(&ha->disco_mutex); >>> >>> diff --git a/drivers/scsi/libsas/sas_expander.c >>> b/drivers/scsi/libsas/sas_expander.c >>> index 7b0e6dcef6e6..5cd720f93f96 100644 >>> --- a/drivers/scsi/libsas/sas_expander.c >>> +++ b/drivers/scsi/libsas/sas_expander.c >>> @@ -2062,7 +2062,7 @@ static int sas_rediscover_dev(struct >>> domain_device *dev, int phy_id, bool last) >>> * first phy,for other phys in this port, we add it to the port to >>> * forming the wide-port. >>> */ >>> -static int sas_rediscover(struct domain_device *dev, const int phy_id) >>> +static void sas_rediscover(struct domain_device *dev, const int phy_id) >>> { >>> struct expander_device *ex = &dev->ex_dev; >>> struct ex_phy *changed_phy = &ex->ex_phy[phy_id]; >>> @@ -2090,7 +2090,9 @@ static int sas_rediscover(struct domain_device >>> *dev, const int phy_id) >>> res = sas_rediscover_dev(dev, phy_id, last); >>> } else >>> res = sas_discover_new(dev, phy_id); >>> - return res; >>> + >>> + pr_debug("ex %016llx phy%d discover returned 0x%x\n", >> >> Hmmm.. this is not just discover, but also rediscover >> > > Yes, will fix. > >>> + SAS_ADDR(dev->sas_addr), phy_id, res); >>> } >>> >>> /** >>> @@ -2102,7 +2104,7 @@ static int sas_rediscover(struct domain_device >>> *dev, const int phy_id) >>> * Discover process only interrogates devices in order to discover the >>> * domain. >>> */ >>> -int sas_ex_revalidate_domain(struct domain_device *port_dev) >>> +void sas_ex_revalidate_domain(struct domain_device *port_dev) >>> { >>> int res; >>> struct domain_device *dev = NULL; >>> @@ -2117,11 +2119,10 @@ int sas_ex_revalidate_domain(struct >>> domain_device *port_dev) >>> res = sas_find_bcast_phy(dev, &phy_id, i, true); >> >> this was missed > > Yes, the return value of sas_find_bcast_phy() is actually unused, and > inside the function debug info has been printed. So we can directly > make it a void function. ok, but how about add a comment like: -if (phy_id == -1) +if (phy_id == -1) /* no remaining broadcast phy found */ > >> >>> if (phy_id == -1) >>> break; >>> - res = sas_rediscover(dev, phy_id); >>> + sas_rediscover(dev, phy_id); >>> i = phy_id + 1; >>> } while (i < ex->num_phys); >>> } >>> - return res; >>> } >>> >>> void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost, >>> diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h >>> index 420156cea3ee..e557bcb0c266 100644 >>> --- a/include/scsi/libsas.h >>> +++ b/include/scsi/libsas.h >>> @@ -692,7 +692,7 @@ int sas_discover_root_expander(struct >>> domain_device *); >>> >>> void sas_init_ex_attr(void); >>> >>> -int sas_ex_revalidate_domain(struct domain_device *); >>> +void sas_ex_revalidate_domain(struct domain_device *); >>> >>> void sas_unregister_domain_devices(struct asd_sas_port *port, int >>> gone); >>> void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *); >>> >> >> >> >> . >> > > > . >