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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 914DFC433FF for ; Mon, 5 Aug 2019 13:50:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 67B012086D for ; Mon, 5 Aug 2019 13:50:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730124AbfHENub (ORCPT ); Mon, 5 Aug 2019 09:50:31 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:44560 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729866AbfHENu2 (ORCPT ); Mon, 5 Aug 2019 09:50:28 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 29691A460A766AD89F5A; Mon, 5 Aug 2019 21:50:24 +0800 (CST) Received: from localhost.localdomain (10.67.212.75) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.439.0; Mon, 5 Aug 2019 21:50:13 +0800 From: John Garry To: , CC: , , , Xiang Chen , "John Garry" Subject: [PATCH 07/15] scsi: hisi_sas: Don't bother clearing status buffer IU in task prep Date: Mon, 5 Aug 2019 21:48:04 +0800 Message-ID: <1565012892-75940-8-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1565012892-75940-1-git-send-email-john.garry@huawei.com> References: <1565012892-75940-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.212.75] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiang Chen For struct hisi_sas_status_buffer, it contains struct hisi_sas_err_record and iu[1024]. The struct iu[1024] will be filled fully by the response of disks, so it is not need to initialize them to 0, but for the struct hisi_sas_err_record, SAS controller only fill some fields of hisi_sas_err_record according to hw designer, so it should be initialised to 0. After the change, cpu utilization percentage of memset() is changed from 1.7% to 0.12%. Signed-off-by: Xiang Chen Signed-off-by: John Garry --- drivers/scsi/hisi_sas/hisi_sas_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index 02ad91c01a44..7efa8dfa0cc1 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -545,7 +545,8 @@ static int hisi_sas_task_prep(struct sas_task *task, memset(slot->cmd_hdr, 0, sizeof(struct hisi_sas_cmd_hdr)); memset(hisi_sas_cmd_hdr_addr_mem(slot), 0, HISI_SAS_COMMAND_TABLE_SZ); - memset(hisi_sas_status_buf_addr_mem(slot), 0, HISI_SAS_STATUS_BUF_SZ); + memset(hisi_sas_status_buf_addr_mem(slot), 0, + sizeof(struct hisi_sas_err_record)); switch (task->task_proto) { case SAS_PROTOCOL_SMP: @@ -2005,7 +2006,8 @@ hisi_sas_internal_abort_task_exec(struct hisi_hba *hisi_hba, int device_id, memset(slot->cmd_hdr, 0, sizeof(struct hisi_sas_cmd_hdr)); memset(hisi_sas_cmd_hdr_addr_mem(slot), 0, HISI_SAS_COMMAND_TABLE_SZ); - memset(hisi_sas_status_buf_addr_mem(slot), 0, HISI_SAS_STATUS_BUF_SZ); + memset(hisi_sas_status_buf_addr_mem(slot), 0, + sizeof(struct hisi_sas_err_record)); hisi_sas_task_prep_abort(hisi_hba, slot, device_id, abort_flag, task_tag); -- 2.17.1