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=-9.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 CC4C3C388F7 for ; Thu, 22 Oct 2020 04:40:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 748882244C for ; Thu, 22 Oct 2020 04:40:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2507593AbgJVEk1 convert rfc822-to-8bit (ORCPT ); Thu, 22 Oct 2020 00:40:27 -0400 Received: from smtp.h3c.com ([60.191.123.56]:53825 "EHLO h3cspam01-ex.h3c.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2502339AbgJVEk1 (ORCPT ); Thu, 22 Oct 2020 00:40:27 -0400 Received: from h3cspam01-ex.h3c.com (localhost [127.0.0.2] (may be forged)) by h3cspam01-ex.h3c.com with ESMTP id 09M30dsO089186 for ; Thu, 22 Oct 2020 11:00:39 +0800 (GMT-8) (envelope-from tian.xianting@h3c.com) Received: from DAG2EX05-BASE.srv.huawei-3com.com ([10.8.0.68]) by h3cspam01-ex.h3c.com with ESMTPS id 09M2xguF086266 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 22 Oct 2020 10:59:42 +0800 (GMT-8) (envelope-from tian.xianting@h3c.com) Received: from DAG2EX03-BASE.srv.huawei-3com.com (10.8.0.66) by DAG2EX05-BASE.srv.huawei-3com.com (10.8.0.68) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Thu, 22 Oct 2020 10:59:43 +0800 Received: from DAG2EX03-BASE.srv.huawei-3com.com ([fe80::5d18:e01c:bbbd:c074]) by DAG2EX03-BASE.srv.huawei-3com.com ([fe80::5d18:e01c:bbbd:c074%7]) with mapi id 15.01.2106.002; Thu, 22 Oct 2020 10:59:43 +0800 From: Tianxianting To: Finn Thain CC: "kashyap.desai@broadcom.com" , "sumit.saxena@broadcom.com" , "shivasharan.srikanteshwara@broadcom.com" , "jejb@linux.ibm.com" , "martin.petersen@oracle.com" , "megaraidlinux.pdl@broadcom.com" , "linux-scsi@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH] scsi: megaraid_sas: use spin_lock() in hard IRQ Thread-Topic: [PATCH] scsi: megaraid_sas: use spin_lock() in hard IRQ Thread-Index: AQHWp3ceROYVx1Vy20ukToM9T7xND6miYAoAgACPazA= Date: Thu, 22 Oct 2020 02:59:43 +0000 Message-ID: <9923f28dd2b34499a17c53e8fa33f1ca@h3c.com> References: <20201021064502.35469-1-tian.xianting@h3c.com> In-Reply-To: Accept-Language: en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.99.141.128] x-sender-location: DAG2 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-DNSRBL: X-MAIL: h3cspam01-ex.h3c.com 09M2xguF086266 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks, Do you mean Megasas raid can be used in m68k arch? -----Original Message----- From: Finn Thain [mailto:fthain@telegraphics.com.au] Sent: Thursday, October 22, 2020 10:25 AM To: tianxianting (RD) Cc: kashyap.desai@broadcom.com; sumit.saxena@broadcom.com; shivasharan.srikanteshwara@broadcom.com; jejb@linux.ibm.com; martin.petersen@oracle.com; megaraidlinux.pdl@broadcom.com; linux-scsi@vger.kernel.org; linux-kernel@vger.kernel.org Subject: Re: [PATCH] scsi: megaraid_sas: use spin_lock() in hard IRQ On Wed, 21 Oct 2020, Xianting Tian wrote: > Since we already in hard IRQ context when running megasas_isr(), On m68k, hard irq context does not mean interrupts are disabled. Are there no other architectures in that category? > so use spin_lock() is enough, which is faster than spin_lock_irqsave(). > Is that measurable? > Signed-off-by: Xianting Tian > --- > drivers/scsi/megaraid/megaraid_sas_base.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c > b/drivers/scsi/megaraid/megaraid_sas_base.c > index 2b7e7b5f3..bd186254d 100644 > --- a/drivers/scsi/megaraid/megaraid_sas_base.c > +++ b/drivers/scsi/megaraid/megaraid_sas_base.c > @@ -3977,15 +3977,14 @@ static irqreturn_t megasas_isr(int irq, void > *devp) { > struct megasas_irq_context *irq_context = devp; > struct megasas_instance *instance = irq_context->instance; > - unsigned long flags; > irqreturn_t rc; > > if (atomic_read(&instance->fw_reset_no_pci_access)) > return IRQ_HANDLED; > > - spin_lock_irqsave(&instance->hba_lock, flags); > + spin_lock(&instance->hba_lock); > rc = megasas_deplete_reply_queue(instance, DID_OK); > - spin_unlock_irqrestore(&instance->hba_lock, flags); > + spin_unlock(&instance->hba_lock); > > return rc; > } >