[PATCH] sched: add new SCHED_BATCH policy

Add a new SCHED_BATCH (3) scheduling policy: such tasks are presumed
CPU-intensive, and will acquire a constant +5 priority level penalty.  Such
policy is nice for workloads that are non-interactive, but which do not
want to give up their nice levels.  The policy is also useful for workloads
that want a deterministic scheduling policy without interactivity causing
extra preemptions (between that workload's tasks).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index f8e609ff1893..7fb541cb8d69 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -244,7 +244,9 @@ static inline void reparent_to_init(void)
         /* Set the exit signal to SIGCHLD so we signal init on exit */
         current->exit_signal = SIGCHLD;
 
-        if ((current->policy == SCHED_NORMAL) && (task_nice(current) < 0))
+        if ((current->policy == SCHED_NORMAL ||
+                        current->policy == SCHED_BATCH)
+                                && (task_nice(current) < 0))
                 set_user_nice(current, 0);
         /* cpus_allowed? */
         /* rt_priority? */