sched: Drop all load weight manipulation for RT tasks
authorLinus Walleij <linus.walleij@stericsson.com>
Mon, 11 Oct 2010 14:36:51 +0000 (16:36 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Mon, 22 Nov 2010 19:03:01 +0000 (11:03 -0800)
commit 17bdcf949d03306b308c5fb694849cd35f119807 upstream.

Load weights are for the CFS, they do not belong in the RT task. This makes all
RT scheduling classes leave the CFS weights alone.

This fixes a real bug as well: I noticed the following phonomena: a process
elevated to SCHED_RR forks with SCHED_RESET_ON_FORK set, and the child is
indeed SCHED_OTHER, and the niceval is indeed reset to 0. However the weight
inserted by set_load_weight() remains at 0, giving the task insignificat
priority.

With this fix, the weight is reset to what the task had before being elevated
to SCHED_RR/SCHED_FIFO.

Cc: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1286807811-10568-1-git-send-email-linus.walleij@stericsson.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
kernel/sched.c

index dc85ceb908322cad7196339f4df8dd58c37b1cec..90235f7efac2db7da8d8f2642e06449335432dcd 100644 (file)
@@ -1858,12 +1858,6 @@ static void dec_nr_running(struct rq *rq)
 
 static void set_load_weight(struct task_struct *p)
 {
-       if (task_has_rt_policy(p)) {
-               p->se.load.weight = 0;
-               p->se.load.inv_weight = WMULT_CONST;
-               return;
-       }
-
        /*
         * SCHED_IDLE tasks get minimal weight:
         */