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_HELO_NONE,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 3CA8EC04AB6 for ; Tue, 28 May 2019 10:33:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EE412075C for ; Tue, 28 May 2019 10:33:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726650AbfE1Kdm (ORCPT ); Tue, 28 May 2019 06:33:42 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:35500 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726305AbfE1Kdm (ORCPT ); Tue, 28 May 2019 06:33:42 -0400 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id B8F3C9335531791EB208; Tue, 28 May 2019 18:33:39 +0800 (CST) Received: from [127.0.0.1] (10.202.227.238) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.439.0; Tue, 28 May 2019 18:33:36 +0800 Subject: Re: [PATCH V2 1/5] scsi: select reply queue from request's CPU To: Ming Lei , Jens Axboe , "Martin K . Petersen" References: <20190527150207.11372-1-ming.lei@redhat.com> <20190527150207.11372-2-ming.lei@redhat.com> CC: , James Bottomley , , "Bart Van Assche" , Hannes Reinecke , Keith Busch , Thomas Gleixner , Don Brace , Kashyap Desai , "Sathya Prakash" , Christoph Hellwig From: John Garry Message-ID: <546f5060-d39a-3057-a181-fa3ff1b921d4@huawei.com> Date: Tue, 28 May 2019 11:33:29 +0100 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: <20190527150207.11372-2-ming.lei@redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.238] X-CFilter-Loop: Reflected Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 27/05/2019 16:02, Ming Lei wrote: > Hisi_sas_v3_hw, hpsa, megaraid and mpt3sas use single blk-mq hw queue > to submit request, meantime apply multiple private reply queues served as > completion queue. The mapping between CPU and reply queue is setup via > pci_alloc_irq_vectors_affinity(PCI_IRQ_AFFINITY) just like the usual > blk-mq queue mapping. > > These drivers always use current CPU(raw_smp_processor_id) to figure out > the reply queue. Switch to use request's CPU to get the reply queue, > so we can drain in-flight request via blk-mq's API before the last CPU of > the reply queue becomes offline. > > Signed-off-by: Ming Lei > --- > drivers/scsi/hisi_sas/hisi_sas_main.c | 5 +++-- > drivers/scsi/hpsa.c | 2 +- > drivers/scsi/megaraid/megaraid_sas_fusion.c | 4 ++-- > drivers/scsi/mpt3sas/mpt3sas_base.c | 16 ++++++++-------- > include/scsi/scsi_cmnd.h | 11 +++++++++++ > 5 files changed, 25 insertions(+), 13 deletions(-) > > diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c > index 8a7feb8ed8d6..ab9d8e7bfc8e 100644 > --- a/drivers/scsi/hisi_sas/hisi_sas_main.c > +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c > @@ -471,9 +471,10 @@ static int hisi_sas_task_prep(struct sas_task *task, > return -ECOMM; > } > > + /* only V3 hardware setup .reply_map */ > if (hisi_hba->reply_map) { > - int cpu = raw_smp_processor_id(); > - unsigned int dq_index = hisi_hba->reply_map[cpu]; > + unsigned int dq_index = hisi_hba->reply_map[ > + scsi_cmnd_cpu(task->uldd_task)]; Hi Ming, There is a problem here. For ATA commands in libsas, task->uldd_task is ata_queued_cmd *, and not a scsi_cmnd *. It comes from https://elixir.bootlin.com/linux/v5.2-rc2/source/drivers/scsi/libsas/sas_ata.c#L212 Please see this later code, where we have this check: if (task->uldd_task) { struct ata_queued_cmd *qc; if (dev_is_sata(device)) { qc = task->uldd_task; scsi_cmnd = qc->scsicmd; } else { scsi_cmnd = task->uldd_task; } } rc = hisi_sas_slot_index_alloc(hisi_hba, scsi_cmnd); I suppose that we could solve by finding scsi_cmnd * earlier in hisi_sas_task_prep(). > > *dq_pointer = dq = &hisi_hba->dq[dq_index]; > } else { > diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c > index 1bef1da273c2..72f9edb86752 100644 > --- a/drivers/scsi/hpsa.c > +++ b/drivers/scsi/hpsa.c > @@ -1145,7 +1145,7 @@ static void __enqueue_cmd_and_start_io(struct ctlr_info *h, [snip] > diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h > index 76ed5e4acd38..ab60883c2c40 100644 > --- a/include/scsi/scsi_cmnd.h > +++ b/include/scsi/scsi_cmnd.h > @@ -332,4 +332,15 @@ static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) > return xfer_len; > } > > +static inline int scsi_cmnd_cpu(struct scsi_cmnd *scmd) > +{ > + if (!scmd || !scmd->request) > + return raw_smp_processor_id(); > + > + if (!scmd->request->mq_ctx) > + return raw_smp_processor_id(); nit: can we combine these tests? Or do you want a distinct check on scmd->request->mq_ctx, since blk_mq_rq_cpu() does not check it? > + > + return blk_mq_rq_cpu(scmd->request); > +} > + > #endif /* _SCSI_SCSI_CMND_H */ Thanks >