All of lore.kernel.org
 help / color / mirror / Atom feed
From: GeunSik Lim <leemgs1@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	linux-rt-users <linux-rt-users@vger.kernel.org>,
	tglx <tglx@linutronix.de>, williams <williams@redhat.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [RESEND] [PATCH 1/2 V3] ftrace: fix typo about map of kernel priority in ftrace.txt file.
Date: Thu, 28 May 2009 10:36:11 +0900	[thread overview]
Message-ID: <1243474571.14685.37.camel@centos51> (raw)
In-Reply-To: <1242884360.31161.77.camel@centos51>



>From 5764d50e29e08d86f7f3b7dff66d7c1ad4762ff8 Mon Sep 17 00:00:00 2001
From: GeunSik,Lim <leemgs1@gmail.com>
Date: Thu, 28 May 2009 09:57:28 +0900
Subject: [PATCH 1/2] ftrace: fix typo about map of kernel priority in ftrace.txt file.

Fix typo about chart to map the kernel priority to user land priorities.

   * About sched_setscheduler(2)
      Processes scheduled under SCHED_FIFO or SCHED_RR
      can have a (user-space) static priority in the range 1 to 99.
      (reference: http://www.kernel.org/doc/man-pages/online/pages/
                  man2/sched_setscheduler.2.html)

   * From: Steven Rostedt
      0 to 98 - maps to RT tasks 99 to 1 (SCHED_RR or SCHED_FIFO)

      99 - maps to internal kernel threads that want to be lower than RT tasks
      but higher than SCHED_OTHER tasks. Although I'm not sure if any
      kernel thread actually uses this. I'm not even sure how this can be
      set, because the internal sched_setscheduler function does not allow
      for it.

      100 to 139 - maps nice levels -20 to 19. These are not set via
      sched_setscheduler, but are set via the nice system call.

      140 - reserved for idle tasks.

        Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com>
        Acked-by     : Steven Rostedt <rostedt@goodmis.org>
        CC           : Ingo Molnar <mingo@elte.hu>
---
 Documentation/trace/ftrace.txt |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e6..e362f50 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -518,9 +518,18 @@ priority with zero (0) being the highest priority and the nice
 values starting at 100 (nice -20). Below is a quick chart to map
 the kernel priority to user land priorities.
 
-  Kernel priority: 0 to 99    ==> user RT priority 99 to 0
-  Kernel priority: 100 to 139 ==> user nice -20 to 19
-  Kernel priority: 140        ==> idle task priority
+   Kernel Space                     User Space
+ ===============================================================
+   0(high) to  98(low)     user RT priority 99(high) to 1(low)
+                           with SCHED_RR or SCHED_FIFO
+ ---------------------------------------------------------------
+  99                       sched_priority is not used in scheduling
+                           decisions(it must be specified as 0)
+ ---------------------------------------------------------------
+ 100(high) to 139(low)     user nice -20(high) to 19(low)
+ ---------------------------------------------------------------
+ 140                       idle task priority
+ ---------------------------------------------------------------
 
 The task states are:
 
-- 
1.6.3.1


-----------------------------------------------
To unsubscribe from this list: send the line "unsubscribe linux-***" 
in the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

GeunSik Lim (  S A M S U N G     E L E C T R O N I C S  )
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://blog.naver.com/invain/
-----------------------------------------------


  parent reply	other threads:[~2009-05-28  1:36 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-21  5:39 [PATCH 0/1 ,v3] sched: fix typo in sched-rt-group.txt file GeunSik Lim
2009-05-28  1:36 ` [RESEND] [PATCH 0/2 V3] description about static priority GeunSik Lim
2009-05-28 13:06   ` Peter Zijlstra
2009-05-29  1:07     ` GeunSik Lim
2009-05-28  1:36 ` GeunSik Lim [this message]
2009-05-28  1:36 ` [RESEND] [PATCH 2/2 V3] sched: fix typo in sched-rt-group.txt file GeunSik Lim

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=1243474571.14685.37.camel@centos51 \
    --to=leemgs1@gmail.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    --cc=williams@redhat.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.