From patchwork Wed Aug 23 09:29:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?UGV0ZXIgV2FuZyAo546L5L+h5Y+LKQ==?= X-Patchwork-Id: 13361927 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4877EEE49B0 for ; Wed, 23 Aug 2023 09:31:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:CC:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=D9B5gKjOEPiOOStjLAPxB+tM/isvMol7/cjHa3Fam3g=; b=1xzLxCtNyEgZpZ+AK+N/wxf0dc z/5Ajhb5DFbYpX1vIryLSdtqJ3uL6Xba9jr4aFLsGuyqQ1KxFpeUJnkYWeFPsd2BuOT0/CtZeAPAD HUtaQDfIs35IGdh/EWAR8kejpr305ZHe8SgoNUa0W2gBmouRSQ3uSoF7toqqNQeIYyqaBhpiZ1fBX IujE6GyDYn2HBF25Y7hFM31ewkjphix5u/Lkr5vtijIv9oAI/loVX2AIiV0O529LknGEW1YWS7MqS 5B6RSDJwM3Kx1wD2Mg88/xtBJMefPNBPEO6n4s19GaNKprxPhcF0LOEFil3kLnImZEc5s28LBcv1N vtJwbAHg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYkCp-00044Z-0n; Wed, 23 Aug 2023 09:31:15 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qYkCl-00043T-2T for linux-mediatek@lists.infradead.org; Wed, 23 Aug 2023 09:31:13 +0000 X-UUID: ba4e1d7a419711ee912e1518a6540028-20230823 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=D9B5gKjOEPiOOStjLAPxB+tM/isvMol7/cjHa3Fam3g=; b=PuTy4LEPziZ5Kin4734GFpT+unRRbGd1A3S58E/gzIMeiCMfTtkiifKXFW/mT2dTmkYbbIFt8e75JTNtMmCr1KsPjNhrAFIaQ8yF/7C7Wb2MuXLzK2jyLlAxlcebHJfcYr1NWvs8uN55pX3eSfZ9FzB3MXtoUx3M8SwiZAwuBdw=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.31,REQID:a2d3a79d-7323-4b90-b329-eac8669ab6a9,IP:0,U RL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:-5 X-CID-META: VersionHash:0ad78a4,CLOUDID:c81a2fc2-1e57-4345-9d31-31ad9818b39f,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:11|1,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR: NO,DKR:0,DKP:0,BRR:0,BRE:0 X-CID-BVR: 0,NGT X-CID-BAS: 0,NGT,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULN X-UUID: ba4e1d7a419711ee912e1518a6540028-20230823 Received: from mtkmbs11n1.mediatek.inc [(172.21.101.185)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 779031735; Wed, 23 Aug 2023 02:30:41 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Wed, 23 Aug 2023 17:29:50 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 23 Aug 2023 17:29:50 +0800 From: To: , , , , , CC: , , , , , , , , , , , , , Subject: [PATCH v1 3/3] ufs: core: fix abnormal scale up after scale down Date: Wed, 23 Aug 2023 17:29:48 +0800 Message-ID: <20230823092948.22734-4-peter.wang@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20230823092948.22734-1-peter.wang@mediatek.com> References: <20230823092948.22734-1-peter.wang@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230823_023111_807068_111589EE X-CRM114-Status: GOOD ( 11.41 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org From: Peter Wang When no active_reqs, devfreq_monitor(Thread A) will suspend clock scaling. But it may have racing with clk_scaling.suspend_work(Thread B) and actually not suspend clock scaling(requue after suspend). Next time after polling_ms, devfreq_monitor read clk_scaling.window_start_t = 0 then scale up clock abnormal. Below is racing step: devfreq->work (Thread A) devfreq_monitor update_devfreq ..... ufshcd_devfreq_target queue_work(hba->clk_scaling.workq, 1 &hba->clk_scaling.suspend_work) ..... 5 queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); 2 hba->clk_scaling.suspend_work (Thread B) ufshcd_clk_scaling_suspend_work __ufshcd_suspend_clkscaling devfreq_suspend_device(hba->devfreq); 3 cancel_delayed_work_sync(&devfreq->work); 4 hba->clk_scaling.window_start_t = 0; ..... Signed-off-by: Peter Wang Reviewed-by: Bart Van Assche Reviewed-by: Bart Van Assche --- drivers/ufs/core/ufshcd.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 017f32b3a789..d3b913d389f4 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -1431,6 +1431,13 @@ static int ufshcd_devfreq_target(struct device *dev, return 0; } + /* Skip scaling clock when clock scaling is suspended */ + if (hba->clk_scaling.is_suspended) { + spin_unlock_irqrestore(hba->host->host_lock, irq_flags); + dev_warn(hba->dev, "clock scaling is suspended, skip"); + return 0; + } + if (!hba->clk_scaling.active_reqs) sched_clk_scaling_suspend_work = true;