From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754872AbdKNLUF (ORCPT ); Tue, 14 Nov 2017 06:20:05 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:53807 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754826AbdKNLT5 (ORCPT ); Tue, 14 Nov 2017 06:19:57 -0500 X-Google-Smtp-Source: AGs4zMYBWMenSuaXCZZE+15MvTzFmo4eaHKlc3gjsWoqo8V0tvacku3p5Q0F7/2g/3Nna/K1T2Sh6w== From: Claudio Scordino To: linux-kernel@vger.kernel.org Cc: Claudio Scordino , Luca Abeni , Jonathan Corbet , "Peter Zijlstra (Intel)" , Ingo Molnar , linux-doc@vger.kernel.org, Tommaso Cucinotta , Mathieu Poirier Subject: [PATCH v2] sched/deadline: fix runtime accounting in documentation Date: Tue, 14 Nov 2017 12:19:26 +0100 Message-Id: <1510658366-28995-1-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 Acked-by: Daniel Bristot de Oliveira CC: Jonathan Corbet CC: "Peter Zijlstra (Intel)" CC: Ingo Molnar CC: linux-doc@vger.kernel.org Cc: Tommaso Cucinotta Cc: Mathieu Poirier --- Documentation/scheduler/sched-deadline.txt | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/Documentation/scheduler/sched-deadline.txt b/Documentation/scheduler/sched-deadline.txt index e89e36e..8ce78f8 100644 --- a/Documentation/scheduler/sched-deadline.txt +++ b/Documentation/scheduler/sched-deadline.txt @@ -204,10 +204,17 @@ 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 (subjected to RT throttling + limits); + - Uinact is the (per runqueue) inactive utilization, computed as + (this_bq - running_bw); + - Uextra is the (per runqueue) extra reclaimable utilization + (subjected to RT throttling limits). Let's now see a trivial example of two deadline tasks with runtime equal -- 2.7.4