mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Luca Abeni <luca.abeni@unitn.it>
To: peterz@infradead.org
Cc: henrik@austad.us, juri.lelli@gmail.com, raistlin@linux.it,
	mingo@kernel.org, linux-kernel@vger.kernel.org,
	linux-doc@vger.kernel.org, Luca Abeni <luca.abeni@unitn.it>
Subject: [PATCH 7/8] Documentation/scheduler/sched-deadline.txt: relationship between tasks' deadlines and scheduling deadlines
Date: Fri, 10 Apr 2015 12:19:54 +0200	[thread overview]
Message-ID: <1428661195-9609-8-git-send-email-luca.abeni@unitn.it> (raw)
In-Reply-To: <1428661195-9609-1-git-send-email-luca.abeni@unitn.it>

Clarify what is the relationship between tasks' parameters and scheduling
parameters, explaining how to set the scheduling parameters so that all the
absolute deadlines of a task are respected.
---
 Documentation/scheduler/sched-deadline.txt |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/Documentation/scheduler/sched-deadline.txt b/Documentation/scheduler/sched-deadline.txt
index 8bec2f5..e605d7f 100644
--- a/Documentation/scheduler/sched-deadline.txt
+++ b/Documentation/scheduler/sched-deadline.txt
@@ -248,9 +248,17 @@ CONTENTS
  the total utilisation is smaller or equal than M then the response times of
  the tasks are limited.
 
- SCHED_DEADLINE can be used to schedule real-time tasks guaranteeing that
- the jobs' deadlines of a task are respected. In order to do this, a task
- must be scheduled by setting:
+ Finally, it is important to understand the relationship between the
+ SCHED_DEADLINE scheduling parameters described in Section 2 (runtime,
+ deadline and period) and the real-time task parameters (WCET, D, P)
+ described in this section. Note that the tasks' temporal constraints are
+ represented by its absolute deadlines d_j = r_j + D described above, while
+ SCHED_DEADLINE schedules the tasks according to scheduling deadlines (see
+ Section 2).
+ If an admission test is used to guarantee that the scheduling deadlines
+ are respected, then SCHED_DEADLINE can be used to schedule real-time tasks
+ guaranteeing that all the jobs' deadlines of a task are respected.
+ In order to do this, a task must be scheduled by setting:
 
   - runtime >= WCET
   - deadline = D
-- 
1.7.9.5


  parent reply	other threads:[~2015-04-10 10:21 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-10 10:19 [PATCH 0/8] SCHED_DEADLINE documentation update Luca Abeni
2015-04-10 10:19 ` [PATCH 1/8] Documentation/scheduler/sched-deadline.txt: correct definition of density as C_i/min{D_i,P_i} Luca Abeni
2015-04-10 10:19 ` [PATCH 2/8] Documentation/scheduler/sched-deadline.txt: fix typos Luca Abeni
2015-04-10 10:19 ` [PATCH 3/8] Documentation/scheduler/sched-deadline.txt: use consistent namings Luca Abeni
2015-04-10 10:19 ` [PATCH 4/8] Documentation/scheduler/sched-deadline.txt: remove _i from sum, max and min Luca Abeni
2015-04-10 10:19 ` [PATCH 5/8] Documentation/scheduler/sched-deadline.txt: Some notes on EDF schedulability Luca Abeni
2015-04-10 10:19 ` [PATCH 6/8] Documentation/scheduler/sched-deadline.txt: add some references Luca Abeni
2015-04-10 10:19 ` Luca Abeni [this message]
2015-04-10 10:19 ` [PATCH 8/8] Documentation/scheduler/sched-deadline.txt: Split Section 3 Luca Abeni
2015-04-11 12:50 ` [PATCH 0/8] SCHED_DEADLINE documentation update Henrik Austad
2015-04-12  9:47 ` Ingo Molnar
2015-04-13 12:39   ` Luca Abeni

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1428661195-9609-8-git-send-email-luca.abeni@unitn.it \
    --to=luca.abeni@unitn.it \
    --cc=henrik@austad.us \
    --cc=juri.lelli@gmail.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=raistlin@linux.it \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®