From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932354AbdHWQBK (ORCPT ); Wed, 23 Aug 2017 12:01:10 -0400 Received: from mail-cys01nam02on0048.outbound.protection.outlook.com ([104.47.37.48]:7020 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932129AbdHWQBF (ORCPT ); Wed, 23 Aug 2017 12:01:05 -0400 Authentication-Results: spf=fail (sender IP is 192.88.168.50) smtp.mailfrom=nxp.com; nxp.com; dkim=none (message not signed) header.d=none;nxp.com; dmarc=fail action=none header.from=nxp.com; From: Matthew Tan To: CC: , , , , , , , , , Matthew Tan Subject: [PATCH] e1000e: changed some expensive calls of udelay to usleep_range Date: Wed, 23 Aug 2017 10:59:45 -0500 Message-ID: <1503503985-3869-1-git-send-email-matthew.tan_1@nxp.com> X-Mailer: git-send-email 2.7.4 X-EOPAttributedMessage: 0 X-Matching-Connectors: 131479776633752177;(91ab9b29-cfa4-454e-5278-08d120cd25b8);() X-Forefront-Antispam-Report: CIP:192.88.168.50;IPV:NLI;CTRY:US;EFV:NLI;SFV:NSPM;SFS:(10009020)(6009001)(336005)(39860400002)(39380400002)(2980300002)(1110001)(1109001)(339900001)(189002)(199003)(50986999)(189998001)(105606002)(36756003)(106466001)(4326008)(47776003)(50226002)(2351001)(305945005)(50466002)(498600001)(77096006)(48376002)(626005)(551934003)(68736007)(6666003)(104016004)(5660300001)(53936002)(110136004)(7416002)(85426001)(6916009)(8936002)(33646002)(356003)(86362001)(97736004)(81156014)(5003940100001)(8656003)(81166006)(2906002)(54906002)(8676002);DIR:OUT;SFP:1101;SCL:1;SRVR:SN2PR03MB2272;H:tx30smr01.am.freescale.net;FPR:;SPF:Fail;PTR:InfoDomainNonexistent;MX:1;A:1;LANG:en; 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Instead usleep_range can be used to be more friendly to userspace since it is preemtable. This is due to udelay using busy-wait loops while usleep_rang uses hrtimers instead. It is recommended to use udelay when the delay is <10us since at that precision overhead of usleep_range hrtimer setup causes issues. However, the replaced calls are for 50us and 100us so this should not be not an issue. Signed-off-by: Matthew Tan --- drivers/net/ethernet/intel/e1000e/phy.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/phy.c b/drivers/net/ethernet/intel/e1000e/phy.c index de13aea..e318fdc 100644 --- a/drivers/net/ethernet/intel/e1000e/phy.c +++ b/drivers/net/ethernet/intel/e1000e/phy.c @@ -158,7 +158,7 @@ s32 e1000e_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data) * the lower time out */ for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) { - udelay(50); + usleep_range(40, 60); mdic = er32(MDIC); if (mdic & E1000_MDIC_READY) break; @@ -183,7 +183,7 @@ s32 e1000e_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data) * reading duplicate data in the next MDIC transaction. */ if (hw->mac.type == e1000_pch2lan) - udelay(100); + usleep_range(90, 100); return 0; } @@ -222,7 +222,7 @@ s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data) * the lower time out */ for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) { - udelay(50); + usleep_range(40, 60); mdic = er32(MDIC); if (mdic & E1000_MDIC_READY) break; @@ -246,7 +246,7 @@ s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data) * reading duplicate data in the next MDIC transaction. */ if (hw->mac.type == e1000_pch2lan) - udelay(100); + usleep_range(90, 110); return 0; } -- 2.7.4