From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757575AbdJMKLN (ORCPT ); Fri, 13 Oct 2017 06:11:13 -0400 Received: from mail-wm0-f42.google.com ([74.125.82.42]:47031 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753320AbdJMKLL (ORCPT ); Fri, 13 Oct 2017 06:11:11 -0400 X-Google-Smtp-Source: ABhQp+RAYTh+N1dkz9hQGxtePQ3nzSL2xcy2aPMj+XWNm29ACxyXViXMpvlUDEBtzB6+53qonmliRQ== From: Claudio Scordino To: linux-kernel@vger.kernel.org Cc: peterz@infradead.org, Claudio Scordino , Luca Abeni Subject: [PATCH] sched/deadline: fix runtime accounting in documentation Date: Fri, 13 Oct 2017 12:08:06 +0200 Message-Id: <1507889286-24651-1-git-send-email-claudio@evidence.eu.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Claudio Scordino Signed-off-by: Luca Abeni --- Documentation/scheduler/sched-deadline.txt | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/Documentation/scheduler/sched-deadline.txt b/Documentation/scheduler/sched-deadline.txt index e89e36e..79f40c6 100644 --- a/Documentation/scheduler/sched-deadline.txt +++ b/Documentation/scheduler/sched-deadline.txt @@ -204,10 +204,16 @@ CONTENTS It does so by decrementing the runtime of the executing task Ti at a pace equal to - dq = -max{ Ui, (1 - Uinact) } dt + dq = -max{ Ui / Umax, (1 - Uinact - Uextra) } dt - where Uinact is the inactive utilization, computed as (this_bq - running_bw), - and Ui is the bandwidth of task Ti. + where: + + - Ui is the bandwidth of task Ti; + - Umax is the maximum reclaimable utilization (subject to RT limits); + - Uinact is the (per runqueue) inactive utilization, computed as + (this_bq - running_bw); + - Uextra is the (per runqueue) extra reclaimable utilization + (subject to RT limits). Let's now see a trivial example of two deadline tasks with runtime equal -- 2.7.4