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 0A9B7C433F5 for ; Thu, 21 Oct 2021 03:18:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D856760FED for ; Thu, 21 Oct 2021 03:18:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230389AbhJUDUu (ORCPT ); Wed, 20 Oct 2021 23:20:50 -0400 Received: from mailgw01.mediatek.com ([60.244.123.138]:57662 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229817AbhJUDUq (ORCPT ); Wed, 20 Oct 2021 23:20:46 -0400 X-UUID: 540c530425584c30a20609a6c5d3765e-20211021 X-UUID: 540c530425584c30a20609a6c5d3765e-20211021 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1947147510; Thu, 21 Oct 2021 11:18:26 +0800 Received: from mtkexhb01.mediatek.inc (172.21.101.102) by mtkmbs07n2.mediatek.inc (172.21.101.141) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 21 Oct 2021 11:18:25 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkexhb01.mediatek.inc (172.21.101.102) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 21 Oct 2021 11:18:25 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 21 Oct 2021 11:18:25 +0800 Message-ID: <0c5b8562d49c7e81323b8a34a42385440f33f798.camel@mediatek.com> Subject: Re: [PATCH] scsi: ufs: mediatek: avoid sched_clock() misuse From: Peter Wang To: Arnd Bergmann , Stanley Chu , "James E.J. Bottomley" , "Martin K. Petersen" CC: Arnd Bergmann , Alim Akhtar , "Avri Altman" , Matthias Brugger , "Bean Huo" , Bart Van Assche , , , , Date: Thu, 21 Oct 2021 11:18:25 +0800 In-Reply-To: <20211018132022.2281589-1-arnd@kernel.org> References: <20211018132022.2281589-1-arnd@kernel.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2021-10-18 at 15:20 +0200, Arnd Bergmann wrote: > From: Arnd Bergmann > > sched_clock() is not meant to be used in portable driver code, > and assuming a particular clock frequency is not how this is > meant to be used. It also causes a build failure because of > a missing header inclusion: > > drivers/scsi/ufs/ufs-mediatek.c:321:12: error: implicit declaration > of function 'sched_clock' [-Werror,-Wimplicit-function-declaration] > timeout = sched_clock() + retry_ms * 1000000UL; > > A better interface to use here ktime_get_mono_fast_ns(), which > works mostly like ktime_get() but is safe to use inside of a > suspend callback. > > Fixes: 9561f58442e4 ("scsi: ufs: mediatek: Support vops pre suspend > to disable auto-hibern8") > Signed-off-by: Arnd Bergmann > --- > drivers/scsi/ufs/ufs-mediatek.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs- > mediatek.c > index d1696db70ce8..a47241ed0a57 100644 > --- a/drivers/scsi/ufs/ufs-mediatek.c > +++ b/drivers/scsi/ufs/ufs-mediatek.c > @@ -318,15 +318,15 @@ static void ufs_mtk_wait_idle_state(struct > ufs_hba *hba, > u32 val, sm; > bool wait_idle; > > - timeout = sched_clock() + retry_ms * 1000000UL; > - > + /* cannot use plain ktime_get() in suspend */ > + timeout = ktime_get_mono_fast_ns() + retry_ms * 1000000UL; Thanks for this patch. > > /* wait a specific time after check base */ > udelay(10); > wait_idle = false; > > do { > - time_checked = sched_clock(); > + time_checked = ktime_get_mono_fast_ns(); > ufs_mtk_dbg_sel(hba); > val = ufshcd_readl(hba, REG_UFS_PROBE); >