From patchwork Thu Aug 31 13:08:26 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: 13371594 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 E2134C83F01 for ; Thu, 31 Aug 2023 13:30:43 +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=MtZHyXQ7DGRPhpbCpbsIJoEBq+bGheQvQ3n4RUzQzJQ=; b=KoWJ0QUIoGfwlRzoVyciiUvMca ORIZ3hva4/oVv1XlsNN6DYjWK3Z7tF+zVqOOuHEiS66UcVaDZKPtbZth50OX/2wYzFjItjXpegiSL 6v6wSvftas1mX24earNywvd850GMsR96pIWfKEDHaO73fWLDjk5DFG0owCMqOGGKkIC3gtB587K3c tMFXz0bx9k1a3GTgLqrDDMjGX2qcrvh6ZGV7AFPVALn2Ngxq/52Nxn5NeUTJod9bADjg1jcct2p5x 8oIzImS0IE/W1FBV3BzwUBGAq8BNmtW+J/3XQsw4yngUYZ6Og29BrYx0nptBcvdc6M+0+1/djQOBV 4IXA386Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qbhkw-00FN2s-0o; Thu, 31 Aug 2023 13:30:42 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qbhkt-00FN1n-1K for linux-mediatek@lists.infradead.org; Thu, 31 Aug 2023 13:30:40 +0000 X-UUID: 90baa804480211ee9b7791016c24628a-20230831 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=MtZHyXQ7DGRPhpbCpbsIJoEBq+bGheQvQ3n4RUzQzJQ=; b=T1D94anUrA3pbS5+DXxwEZs6I6ep9KcWaLV9BKz8hud1JtV15G6Elp9mnl0GdRpsTXB2hAdiFKP+Ut5zeu+4nU14jH/MQmEDsbYMsKimA7eYsXxVWildY4Hw3hdz4oFZzYUPeZUhGPcwasF3P43oMR8tP+EtBtZMYktDs2HFAGM=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.31,REQID:c229f1c7-6c80-4a5e-b44a-eb065d6a91c0,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:49bd6813-4929-4845-9571-38c601e9c3c9,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: 90baa804480211ee9b7791016c24628a-20230831 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 1621864693; Thu, 31 Aug 2023 06:30:35 -0700 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) 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; Thu, 31 Aug 2023 21:08:30 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Thu, 31 Aug 2023 21:08:30 +0800 From: To: , , , , , CC: , , , , , , , , , , , , , Subject: [PATCH v2 3/3] ufs: core: fix abnormal scale up after scale down Date: Thu, 31 Aug 2023 21:08:26 +0800 Message-ID: <20230831130826.5592-4-peter.wang@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20230831130826.5592-1-peter.wang@mediatek.com> References: <20230831130826.5592-1-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-20230831_063039_461867_ACD2A0D0 X-CRM114-Status: GOOD ( 11.47 ) 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 --- 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 057549b0e586..d72fa2c1e316 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -1430,6 +1430,13 @@ 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;