From patchwork Mon Sep 10 17:30:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Smart X-Patchwork-Id: 10594645 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A6FA4920 for ; Mon, 10 Sep 2018 17:31:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9066F2933F for ; Mon, 10 Sep 2018 17:31:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8294129345; Mon, 10 Sep 2018 17:31:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DD912933F for ; Mon, 10 Sep 2018 17:31:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728436AbeIJW0W (ORCPT ); Mon, 10 Sep 2018 18:26:22 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:46615 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728197AbeIJW0V (ORCPT ); Mon, 10 Sep 2018 18:26:21 -0400 Received: by mail-pf1-f195.google.com with SMTP id u24-v6so10806857pfn.13 for ; Mon, 10 Sep 2018 10:31:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=5ftOSNtWG2ApoP5V83hay4sDEdLUbxvIIF0xs459ias=; b=T09bYKMWwxL1uDM2pIy9qbXoP+U81NwR8KMKUnJ8hef93Xs4mtx19URye24SEEnOzZ MFS57lnxtVgtQyT6F2HfzOAsHj5hnOAi9WkUdFD0jd4aG09iJsN58/3MpMTObQE8H5oz STtPADLx2ygVbuTIlx+5OLmUaIs+jpsgUc4TrRugs+WR94cJJVkNpmcM+zRDsWkLs5nx xNHRXAYqrsoGrNW8mvQbehu52N/mlVgUsi/ofrguS4CdOyqe/8SFVS4Vxk3QNAWRz/pI DOvCYvk0HDBDNGKRrz9Sun22kTiPfVp129fewhrCZ4pGRbKnSSGibXfJPHytfahkxdBp nmLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=5ftOSNtWG2ApoP5V83hay4sDEdLUbxvIIF0xs459ias=; b=qAoirYARCaa54v5YiHSDYD92X15612M/t9YZ+6vYX9x9NHROJpRenshFDwRfTnVLTt FjqkfNmTnvE2j3NAuOigSgQzRSs+CiS7ki7sEgSDQojhOM593j7vdLHsR3YOR5xWyEbd CCNSorhrrjCrSUU5Xzm6yDhcu75Y9Wmhh1lLJ+ZFXe+23qfdMWE7eniX6gJmyWpWT8It 9o1ncTS/Ov9mpZgJ5zW0Ho2N4F6JsyDsHQHqA+q/5N0yX0oOlfcuYE+VSPLuOAU7kHnL F33lrDVQap/Joc4WBO83ks2yWNtUq/1GPd2qRTtwdfsoubMMu3jsTw2/V6O3QM8xzlw0 jWtw== X-Gm-Message-State: APzg51DGcM2wrG2Tm5uxaI/oBCmNn1C0R8jrfAv7RZH/9brB0IcLs/ME jYS1mZmxQCCk50gu7f1A8ScqnPn1 X-Google-Smtp-Source: ANB0VdZqTyUdFx9RkPWr+L1xcLl7/wil+TWDcMkSVsXSdmLM2Xeqp901Tc3OFKneYNc3sMI5KmzJ9Q== X-Received: by 2002:a63:170b:: with SMTP id x11-v6mr23195438pgl.364.1536600672585; Mon, 10 Sep 2018 10:31:12 -0700 (PDT) Received: from pallmd1.broadcom.com ([192.19.223.250]) by smtp.gmail.com with ESMTPSA id 6-v6sm22134045pgf.38.2018.09.10.10.31.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 10 Sep 2018 10:31:11 -0700 (PDT) From: James Smart To: linux-scsi@vger.kernel.org Cc: James Smart , Dick Kennedy , James Smart Subject: [PATCH 09/11] lpfc: reduce locking when updating statistics Date: Mon, 10 Sep 2018 10:30:49 -0700 Message-Id: <20180910173051.6272-10-jsmart2021@gmail.com> X-Mailer: git-send-email 2.13.1 In-Reply-To: <20180910173051.6272-1-jsmart2021@gmail.com> References: <20180910173051.6272-1-jsmart2021@gmail.com> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently, on each io completion, the stats update routine indiscriminately holds a lock. While holding the adapter-wide lock, checks are made to check whether status are being tracked. When disabled (the default), the locking wasted a lot of cycles. Check for stats enablement before taking the lock. Signed-off-by: Dick Kennedy Signed-off-by: James Smart --- drivers/scsi/lpfc/lpfc_scsi.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c index 200b5bca1f5f..f2d5420be413 100644 --- a/drivers/scsi/lpfc/lpfc_scsi.c +++ b/drivers/scsi/lpfc/lpfc_scsi.c @@ -202,8 +202,8 @@ lpfc_sli4_set_rsp_sgl_last(struct lpfc_hba *phba, static void lpfc_update_stats(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd) { - struct lpfc_rport_data *rdata = lpfc_cmd->rdata; - struct lpfc_nodelist *pnode = rdata->pnode; + struct lpfc_rport_data *rdata; + struct lpfc_nodelist *pnode; struct scsi_cmnd *cmd = lpfc_cmd->pCmd; unsigned long flags; struct Scsi_Host *shost = cmd->device->host; @@ -211,17 +211,19 @@ lpfc_update_stats(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd) unsigned long latency; int i; - if (cmd->result) + if (!vport->stat_data_enabled || + vport->stat_data_blocked || + (cmd->result)) return; latency = jiffies_to_msecs((long)jiffies - (long)lpfc_cmd->start_time); + rdata = lpfc_cmd->rdata; + pnode = rdata->pnode; spin_lock_irqsave(shost->host_lock, flags); - if (!vport->stat_data_enabled || - vport->stat_data_blocked || - !pnode || - !pnode->lat_data || - (phba->bucket_type == LPFC_NO_BUCKET)) { + if (!pnode || + !pnode->lat_data || + (phba->bucket_type == LPFC_NO_BUCKET)) { spin_unlock_irqrestore(shost->host_lock, flags); return; }