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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44C38C433F5 for ; Thu, 7 Oct 2021 20:29:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DE376103B for ; Thu, 7 Oct 2021 20:29:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233857AbhJGUbb (ORCPT ); Thu, 7 Oct 2021 16:31:31 -0400 Received: from mail-pj1-f48.google.com ([209.85.216.48]:52873 "EHLO mail-pj1-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233598AbhJGUba (ORCPT ); Thu, 7 Oct 2021 16:31:30 -0400 Received: by mail-pj1-f48.google.com with SMTP id oa4so5092605pjb.2 for ; Thu, 07 Oct 2021 13:29:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CLO3bI2ukg4hM2P6jquFRoxBPqd4s8Qin+BxyvHB8to=; b=aMcCG6Oug/MhSHtq/pwpi8fWJS4IZeddjaWGos+ONCZ3hv/rMjlQ4YuYtyPL9uIkpO a5dNhlnQAZZbbVQRDA7ej4zw1I1Y+vrX1SSz6A57q1P2NBGxKveNRhyisNETY5THr/U/ 24yXSW+5vfb8B+jZy4qEPKL8sOUoA2oK0x+00B17dzjzjUj8O0FY9C0qgkiRMfW+78/f FfPhwEzQ0XPtEKsFeMaZi7bxU/Nfe9at2XPK1tBB7j/Fc9vuhZjuFUqiSOh+g3iGObtE 88QBpgIn1YKnyRX0p7sEg2KgiOd1oFFdHnwBr6A+vdDMI1lfTFvIKY8Bq3ZQ6NM/DPsS g+Rg== X-Gm-Message-State: AOAM531BjVzuX2KHp+iiMPIBKOG/WAB3WqDZZ/S1VAwqbaVr5W0y6ZV3 LhU8eYCG54dQfw3FqYM8f2y3ToJNe20= X-Google-Smtp-Source: ABdhPJzCYvvEyW7yV9YzOn2ZOoT3C4/A9R5mlI4Rxelk95YYaYmt3wpOZLJd7ds2JTv5LeRlXKLRnw== X-Received: by 2002:a17:90b:1642:: with SMTP id il2mr7130874pjb.167.1633638576424; Thu, 07 Oct 2021 13:29:36 -0700 (PDT) Received: from bvanassche-linux.mtv.corp.google.com ([2620:15c:211:201:ae88:8f16:b90b:5f1d]) by smtp.gmail.com with ESMTPSA id x35sm303499pfh.52.2021.10.07.13.29.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Oct 2021 13:29:35 -0700 (PDT) From: Bart Van Assche To: "Martin K . Petersen" Cc: linux-scsi@vger.kernel.org, Bart Van Assche , Benjamin Block , Bean Huo , Hannes Reinecke , Ming Lei , Christoph Hellwig , "James E.J. Bottomley" Subject: [PATCH v3 01/88] scsi: core: Use a structure member to track the SCSI command submitter Date: Thu, 7 Oct 2021 13:27:56 -0700 Message-Id: <20211007202923.2174984-2-bvanassche@acm.org> X-Mailer: git-send-email 2.33.0.882.g93a45727a2-goog In-Reply-To: <20211007202923.2174984-1-bvanassche@acm.org> References: <20211007202923.2174984-1-bvanassche@acm.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Conditional statements are faster than indirect calls. Use a structure member to track the SCSI command submitter such that later patches can call scsi_done(scmd) instead of scmd->scsi_done(scmd). The asymmetric behavior that scsi_send_eh_cmnd() sets the submission context to the SCSI error handler and that it does not restore the submission context to the SCSI core is retained. Reviewed-by: Benjamin Block Reviewed-by: Bean Huo Cc: Hannes Reinecke Cc: Ming Lei Cc: Christoph Hellwig Signed-off-by: Bart Van Assche --- drivers/scsi/scsi_error.c | 17 ++++++----------- drivers/scsi/scsi_lib.c | 10 ++++++++++ drivers/scsi/scsi_priv.h | 1 + include/scsi/scsi_cmnd.h | 7 +++++++ 4 files changed, 24 insertions(+), 11 deletions(-) diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index b6c86cce57bf..3de03925550e 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -50,8 +50,6 @@ #include -static void scsi_eh_done(struct scsi_cmnd *scmd); - /* * These should *probably* be handled by the host itself. * Since it is allowed to sleep, it probably should. @@ -520,7 +518,8 @@ enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd) /* handler does not care. Drop down to default handling */ } - if (scmd->cmnd[0] == TEST_UNIT_READY && scmd->scsi_done != scsi_eh_done) + if (scmd->cmnd[0] == TEST_UNIT_READY && + scmd->submitter != SUBMITTED_BY_SCSI_ERROR_HANDLER) /* * nasty: for mid-layer issued TURs, we need to return the * actual sense data without any recovery attempt. For eh @@ -782,7 +781,7 @@ static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd) * scsi_eh_done - Completion function for error handling. * @scmd: Cmd that is done. */ -static void scsi_eh_done(struct scsi_cmnd *scmd) +void scsi_eh_done(struct scsi_cmnd *scmd) { struct completion *eh_action; @@ -1082,7 +1081,7 @@ static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd, shost->eh_action = &done; scsi_log_send(scmd); - scmd->scsi_done = scsi_eh_done; + scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER; /* * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can @@ -1109,6 +1108,7 @@ static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd, if (rtn) { if (timeleft > stall_for) { scsi_eh_restore_cmnd(scmd, &ses); + timeleft -= stall_for; msleep(jiffies_to_msecs(stall_for)); goto retry; @@ -2338,11 +2338,6 @@ void scsi_report_device_reset(struct Scsi_Host *shost, int channel, int target) } EXPORT_SYMBOL(scsi_report_device_reset); -static void -scsi_reset_provider_done_command(struct scsi_cmnd *scmd) -{ -} - /** * scsi_ioctl_reset: explicitly reset a host/bus/target/device * @dev: scsi_device to operate on @@ -2379,7 +2374,7 @@ scsi_ioctl_reset(struct scsi_device *dev, int __user *arg) scsi_init_command(dev, scmd); scmd->cmnd = scsi_req(rq)->cmd; - scmd->scsi_done = scsi_reset_provider_done_command; + scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL; memset(&scmd->sdb, 0, sizeof(scmd->sdb)); scmd->cmd_len = 0; diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 5f5ad22512f5..3fd24144b805 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1577,6 +1577,15 @@ static blk_status_t scsi_prepare_cmd(struct request *req) static void scsi_mq_done(struct scsi_cmnd *cmd) { + switch (cmd->submitter) { + case SUBMITTED_BY_BLOCK_LAYER: + break; + case SUBMITTED_BY_SCSI_ERROR_HANDLER: + return scsi_eh_done(cmd); + case SUBMITTED_BY_SCSI_RESET_IOCTL: + return; + } + if (unlikely(blk_should_fake_timeout(scsi_cmd_to_rq(cmd)->q))) return; if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state))) @@ -1683,6 +1692,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, scsi_set_resid(cmd, 0); memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); + cmd->submitter = SUBMITTED_BY_BLOCK_LAYER; cmd->scsi_done = scsi_mq_done; blk_mq_start_request(req); diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h index 6d9152031a40..b7f963149352 100644 --- a/drivers/scsi/scsi_priv.h +++ b/drivers/scsi/scsi_priv.h @@ -84,6 +84,7 @@ void scsi_eh_ready_devs(struct Scsi_Host *shost, int scsi_eh_get_sense(struct list_head *work_q, struct list_head *done_q); int scsi_noretry_cmd(struct scsi_cmnd *scmd); +void scsi_eh_done(struct scsi_cmnd *scmd); /* scsi_lib.c */ extern int scsi_maybe_unblock_host(struct scsi_device *sdev); diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index a2315aac93c7..893c24aab8e4 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -64,6 +64,12 @@ struct scsi_pointer { #define SCMD_STATE_COMPLETE 0 #define SCMD_STATE_INFLIGHT 1 +enum scsi_cmnd_submitter { + SUBMITTED_BY_BLOCK_LAYER = 0, + SUBMITTED_BY_SCSI_ERROR_HANDLER = 1, + SUBMITTED_BY_SCSI_RESET_IOCTL = 2, +} __packed; + struct scsi_cmnd { struct scsi_request req; struct scsi_device *device; @@ -89,6 +95,7 @@ struct scsi_cmnd { unsigned char prot_op; unsigned char prot_type; unsigned char prot_flags; + enum scsi_cmnd_submitter submitter; unsigned short cmd_len; enum dma_data_direction sc_data_direction;