Commit-ID: 37a8f8590f307db8f8cfa62dfd82b3fc0978607c Gitweb: https://git.kernel.org/tip/37a8f8590f307db8f8cfa62dfd82b3fc0978607c Author: Sebastian Andrzej Siewior <bige...@linutronix.de> AuthorDate: Wed, 3 Apr 2019 23:08:21 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 16 Apr 2019 10:06:08 +0200
sched/core: Document that RT task priorities are 1...99 John identified three files which claim that RT task priorities start at zero. As far as I understand, 0 is used for DL and has nothing to do wihich RT priorities as identified by the RT policy. Correct the comment, valid RT priorities are in the range from 1 to 99. Reported-by: John Ogness <john.ogn...@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/20190403210821.10916-1-bige...@linutronix.de Signed-off-by: Ingo Molnar <mi...@kernel.org> --- Documentation/scheduler/sched-rt-group.txt | 2 +- include/linux/sched/prio.h | 2 +- kernel/sched/cpupri.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt index d8fce3e78457..23f8f8465a77 100644 --- a/Documentation/scheduler/sched-rt-group.txt +++ b/Documentation/scheduler/sched-rt-group.txt @@ -175,7 +175,7 @@ get their allocated time. Implementing SCHED_EDF might take a while to complete. Priority Inheritance is the biggest challenge as the current linux PI infrastructure is geared towards -the limited static priority levels 0-99. With deadline scheduling you need to +the limited static priority levels 1-99. With deadline scheduling you need to do deadline inheritance (since priority is inversely proportional to the deadline delta (deadline - now)). diff --git a/include/linux/sched/prio.h b/include/linux/sched/prio.h index 7d64feafc408..6986c3235684 100644 --- a/include/linux/sched/prio.h +++ b/include/linux/sched/prio.h @@ -8,7 +8,7 @@ /* * Priority of a process goes from 0..MAX_PRIO-1, valid RT - * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH + * priority is 1..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority * values are inverted: lower p->prio value means higher priority. * diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h index 7dc20a3232e7..40257a97fb8f 100644 --- a/kernel/sched/cpupri.h +++ b/kernel/sched/cpupri.h @@ -5,7 +5,7 @@ #define CPUPRI_INVALID -1 #define CPUPRI_IDLE 0 #define CPUPRI_NORMAL 1 -/* values 2-101 are RT priorities 0-99 */ +/* values 2-101 are RT priorities 1-99 */ struct cpupri_vec { atomic_t count;
