From patchwork Mon Oct 26 19:51:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jaegeuk Kim X-Patchwork-Id: 11858653 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E3A906A2 for ; Mon, 26 Oct 2020 19:51:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C312620795 for ; Mon, 26 Oct 2020 19:51:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603741910; bh=xTNw6+WS4QruCfRu7I59YvY2zjaDS2nJzRs7S5LxRMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Up9O9rNBWuv159SKRmsfk2RYBxAI8mrv4qnts4FPBLGLXFOzyfrzXWMkeXgo4wd+A emPfvx56vuWpGJRI6t6jq5dQNjzeJ40Xt+9c9jB03IB/FP5uiYmlSCgld7562mKctx o+IpkLJvBlwnCwhL3ZSLvpjYamnWV/C2oHDPm5E0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728945AbgJZTvg (ORCPT ); Mon, 26 Oct 2020 15:51:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:47680 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728866AbgJZTve (ORCPT ); Mon, 26 Oct 2020 15:51:34 -0400 Received: from localhost (unknown [104.132.1.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D18F521655; Mon, 26 Oct 2020 19:51:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603741894; bh=xTNw6+WS4QruCfRu7I59YvY2zjaDS2nJzRs7S5LxRMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QalBONmOfrWvb1o7TEOiZjNdcDoj92PpWFnGLczmkdjyLvTc9jj7DcfPzUhph67Pe bStdx8VAiYQSLiwcZUktbSb4DIaLGQlnFS8MPJuqITsVqPut7vLfiru+VLk652KZAp 8wHq8K11i1xgRMxT8IwhTGaAHvhIFDI3tNlWNYkY= From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, kernel-team@android.com Cc: cang@codeaurora.org, alim.akhtar@samsung.com, avri.altman@wdc.com, bvanassche@acm.org, Jaegeuk Kim , Asutosh Das Subject: [PATCH v4 5/5] scsi: ufs: fix clkgating on/off correctly Date: Mon, 26 Oct 2020 12:51:24 -0700 Message-Id: <20201026195124.363096-6-jaegeuk@kernel.org> X-Mailer: git-send-email 2.29.0.rc1.297.gfa9743e501-goog In-Reply-To: <20201026195124.363096-1-jaegeuk@kernel.org> References: <20201026195124.363096-1-jaegeuk@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The below call stack prevents clk_gating at every IO completion. We can remove the condition, ufshcd_any_tag_in_use(), since clkgating_work will check it again. ufshcd_complete_requests(struct ufs_hba *hba) ufshcd_transfer_req_compl() __ufshcd_transfer_req_compl() __ufshcd_release(hba) if (ufshcd_any_tag_in_use() == 1) return; ufshcd_tmc_handler(hba); blk_mq_tagset_busy_iter(); Note that, this still requires a work to deal with a potential racy condition when user sets clkgating.delay_ms to very small value. That can cause preventing clkgating by the check of ufshcd_any_tag_in_use() in gate_work. Fixes: 7252a3603015 ("scsi: ufs: Avoid busy-waiting by eliminating tag conflicts") Signed-off-by: Jaegeuk Kim Reviewed-by: Asutosh Das Reviewed-by: Can Guo --- drivers/scsi/ufs/ufshcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index b8a54d09e750..86c8dee01ca9 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1746,7 +1746,7 @@ static void __ufshcd_release(struct ufs_hba *hba) if (hba->clk_gating.active_reqs || hba->clk_gating.is_suspended || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL || - ufshcd_any_tag_in_use(hba) || hba->outstanding_tasks || + hba->outstanding_tasks || hba->active_uic_cmd || hba->uic_async_done || hba->clk_gating.state == CLKS_OFF) return;