From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5EF18C5CFE7 for ; Wed, 11 Jul 2018 14:13:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E40D720871 for ; Wed, 11 Jul 2018 14:13:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E40D720871 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388374AbeGKOSR (ORCPT ); Wed, 11 Jul 2018 10:18:17 -0400 Received: from ozlabs.org ([203.11.71.1]:48503 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726639AbeGKOSR (ORCPT ); Wed, 11 Jul 2018 10:18:17 -0400 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPSA id 41Qgz86312zB4MP; Thu, 12 Jul 2018 00:13:40 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au From: Michael Ellerman To: Daniel Klamt , benh@kernel.crashing.org Cc: paulus@samba.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-kernel@i4.cs.fau.de, Daniel Klamt , Bjoern Noetel Subject: Re: [PATCH] powerpc: Replaced msleep with usleep_range In-Reply-To: <1531144679-31675-1-git-send-email-eleon@ele0n.de> References: <1531144679-31675-1-git-send-email-eleon@ele0n.de> Date: Thu, 12 Jul 2018 00:13:39 +1000 Message-ID: <878t6hami4.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Daniel, Daniel Klamt writes: > Replaced msleep for less than 10ms with usleep_range because will > often sleep longer than intended. > For original explanation see: > Documentation/timers/timers-howto.txt > > Signed-off-by: Daniel Klamt > Signed-off-by: Bjoern Noetel > --- > arch/powerpc/sysdev/xive/native.c | 24 ++++++++++++------------ > 1 file changed, 12 insertions(+), 12 deletions(-) > > diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c > index 311185b9960a..b164b1cdf4d6 100644 > --- a/arch/powerpc/sysdev/xive/native.c > +++ b/arch/powerpc/sysdev/xive/native.c > @@ -109,7 +109,7 @@ int xive_native_configure_irq(u32 hw_irq, u32 target, u8 prio, u32 sw_irq) > rc = opal_xive_set_irq_config(hw_irq, target, prio, sw_irq); > if (rc != OPAL_BUSY) > break; > - msleep(1); > + usleep_range(1000, 1100) > } We have actually recently added OPAL_BUSY_DELAY_MS (see opal.h) and should convert these to use that. eg: msleep(OPAL_BUSY_DELAY_MS); That has the effect of documenting that this is a short sleep to wait for opal (our firmware), and we aren't concerned about rounding errors in msleep(). If you send me a patch doing that I'd be happy to merge it. cheers