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* [PATCH 1/1 ,v3] ftrace: fix typo in ftrace.txt file
@ 2009-05-21  5:39 GeunSik Lim
  2009-05-21 16:14 ` Steven Rostedt
  0 siblings, 1 reply; 2+ messages in thread
From: GeunSik Lim @ 2009-05-21  5:39 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: williams, tglx, Steven Rostedt, Peter Zijlstra, linux-rt-users,
	linux-kernel

[-- Attachment #1: Type: text/plain, Size: 3192 bytes --]


-- 

commit 16d92cb2334b19751db851d221aab814cd9da1af
Author: GeunSik,Lim <leemgs1@gmail.com>
Date:   Thu May 21 14:31:17 2009 +0900

            ftrace: fix typo 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>

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:
 

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GeunSik Lim (ELS - OS Group - S/W Lab - SAIT - SAMSUNG)
e-Mail  :1) geunsik.lim@samsung.com
         2) leemgs@gmail.com , leemgs1@gmail.com
HomePage: http://intomail.dnip.net/invain/me/
-----------------------------------------------

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[-- Type: text/x-patch, Size: 2661 bytes --]

commit 16d92cb2334b19751db851d221aab814cd9da1af
Author: GeunSik,Lim <leemgs1@gmail.com>
Date:   Thu May 21 14:31:17 2009 +0900

            ftrace: fix typo 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>

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:
 

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2009-05-21  5:39 [PATCH 1/1 ,v3] ftrace: fix typo in ftrace.txt file GeunSik Lim
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