From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751191AbeAYKWY (ORCPT ); Thu, 25 Jan 2018 05:22:24 -0500 Received: from mail-io0-f193.google.com ([209.85.223.193]:44901 "EHLO mail-io0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbeAYKWV (ORCPT ); Thu, 25 Jan 2018 05:22:21 -0500 X-Google-Smtp-Source: AH8x226r5bqhyKt3dsCFIGw+iH7cmeEPKq5LWlmR29Scnk2pUSipPBjLHafgCBcqFim5OzHG2U9B/A== From: Jia-Ju Bai To: tj@kernel.org, mlord@pobox.com Cc: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] ata: sata_mv: Replace mdelay with usleep_range in mv_reset_channel Date: Thu, 25 Jan 2018 18:26:52 +0800 Message-Id: <1516876013-12653-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After checking all possible call chains to mv_reset_channel here, my tool finds that mv_reset_channel is never called in atomic context, namely never in an interrupt handler or holding a spinlock. Thus mdelay can be replaced with usleep_range to avoid busy wait. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai --- drivers/ata/sata_mv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index cc208b7..42d4589 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -3596,7 +3596,7 @@ static void mv_reset_channel(struct mv_host_priv *hpriv, void __iomem *mmio, hpriv->ops->phy_errata(hpriv, mmio, port_no); if (IS_GEN_I(hpriv)) - mdelay(1); + usleep_range(500, 1000); } static void mv_pmp_select(struct ata_port *ap, int pmp) -- 1.7.9.5