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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 95288C4360F for ; Wed, 3 Apr 2019 21:08:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 686792082C for ; Wed, 3 Apr 2019 21:08:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726547AbfDCVIh (ORCPT ); Wed, 3 Apr 2019 17:08:37 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:42833 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726099AbfDCVIh (ORCPT ); Wed, 3 Apr 2019 17:08:37 -0400 Received: from localhost ([127.0.0.1] helo=flow.W.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hBn7Y-0000mx-HO; Wed, 03 Apr 2019 23:08:32 +0200 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Peter Zijlstra , tglx@linutronix.de, Sebastian Andrzej Siewior , John Ogness Subject: [PATCH] =?UTF-8?q?sched:=20Document=20that=20RT=20task=20prioriti?= =?UTF-8?q?es=20are=201=E2=80=A699?= Date: Wed, 3 Apr 2019 23:08:21 +0200 Message-Id: <20190403210821.10916-1-bigeasy@linutronix.de> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org John identified three files which claim that RT task priorities start at zero. As far as I understand, 0 is used for DL and has nothing to do wihich RT priorities as identified by the RT policy. Correct the comment, valid RT priorities are in the range from 1 to 99. Reported-by: John Ogness Signed-off-by: Sebastian Andrzej Siewior --- Documentation/scheduler/sched-rt-group.txt | 2 +- include/linux/sched/prio.h | 2 +- kernel/sched/cpupri.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt index d8fce3e784574..23f8f8465a775 100644 --- a/Documentation/scheduler/sched-rt-group.txt +++ b/Documentation/scheduler/sched-rt-group.txt @@ -175,7 +175,7 @@ get their allocated time. Implementing SCHED_EDF might take a while to complete. Priority Inheritance is the biggest challenge as the current linux PI infrastructure is geared towards -the limited static priority levels 0-99. With deadline scheduling you need to +the limited static priority levels 1-99. With deadline scheduling you need to do deadline inheritance (since priority is inversely proportional to the deadline delta (deadline - now)). diff --git a/include/linux/sched/prio.h b/include/linux/sched/prio.h index 7d64feafc408e..6986c32356842 100644 --- a/include/linux/sched/prio.h +++ b/include/linux/sched/prio.h @@ -8,7 +8,7 @@ /* * Priority of a process goes from 0..MAX_PRIO-1, valid RT - * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH + * priority is 1..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority * values are inverted: lower p->prio value means higher priority. * diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h index 7dc20a3232e72..40257a97fb8f2 100644 --- a/kernel/sched/cpupri.h +++ b/kernel/sched/cpupri.h @@ -5,7 +5,7 @@ #define CPUPRI_INVALID -1 #define CPUPRI_IDLE 0 #define CPUPRI_NORMAL 1 -/* values 2-101 are RT priorities 0-99 */ +/* values 2-101 are RT priorities 1-99 */ struct cpupri_vec { atomic_t count; -- 2.20.1