linux/kernel/sched
Thomas Gleixner 32e475d76a sched: Expose preempt_schedule_irq()
Tony reported that aa0d532605 ("ia64: Use preempt_schedule_irq")
broke PREEMPT=n builds on ia64.

Ok, wrapped my brain around it. I tripped over the magic asm foo which
has a single need_resched check and schedule point for both sys call
return and interrupt return.

So you need the schedule_preempt_irq() for kernel preemption from
interrupt return while on a normal syscall preemption a schedule would
be sufficient. But using schedule_preempt_irq() is not harmful here in
any way. It just sets the preempt_active bit also in cases where it
would not be required.

Even on preempt=n kernels adding the preempt_active bit is completely
harmless. So instead of having an extra function, moving the existing
one out of the ifdef PREEMPT looks like the sanest thing to do.

It would also allow getting rid of various other sti/schedule/cli asm
magic in other archs.

Reported-and-Tested-by: Tony Luck <tony.luck@gmail.com>
Fixes: aa0d532605 ("ia64: Use preempt_schedule_irq")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[slightly edited Changelog]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311211230030.30673@ionos.tec.linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-27 11:04:53 +01:00
..
Makefile sched: Move completion code from core.c to completion.c 2013-11-06 07:49:19 +01:00
auto_group.c sched/autogroup: Fix race with task_groups list 2013-05-28 09:40:22 +02:00
auto_group.h Revert "sched/autogroup: Fix crash on reboot when autogroup is disabled" 2012-12-11 10:23:45 +01:00
clock.c sched_clock: Prevent 64bit inatomicity on 32bit systems 2013-04-08 11:50:44 +02:00
completion.c sched: Move completion code from core.c to completion.c 2013-11-06 07:49:19 +01:00
core.c sched: Expose preempt_schedule_irq() 2013-11-27 11:04:53 +01:00
cpuacct.c cgroup: pass around cgroup_subsys_state instead of cgroup in file methods 2013-08-08 20:11:24 -04:00
cpuacct.h sched/cpuacct: Initialize root cpuacct earlier 2013-04-10 13:54:20 +02:00
cpupri.c sched: Fix some kernel-doc warnings 2013-07-18 09:58:21 +02:00
cpupri.h
cputime.c Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-09-05 12:36:46 -07:00
debug.c sched: Avoid throttle_cfs_rq() racing with period_timer stopping 2013-10-29 12:02:32 +01:00
fair.c sched: Check sched_domain before computing group power 2013-11-19 17:01:15 +01:00
features.h sched/numa: Resist moving tasks towards nodes with fewer hinting faults 2013-10-09 12:40:27 +02:00
idle_task.c sched/numa: Introduce migrate_swap() 2013-10-09 12:40:46 +02:00
proc.c sched: Change get_rq_runnable_load() to static and inline 2013-06-27 10:07:44 +02:00
rt.c sched/rt: Fix task_tick_rt() comment 2013-10-26 12:25:21 +02:00
sched.h sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus 2013-11-06 12:37:55 +01:00
stats.c fix a leak in /proc/schedstats 2013-04-29 15:41:45 -04:00
stats.h sched: Micro-optimize by dropping unnecessary task_rq() calls 2013-09-25 13:51:06 +02:00
stop_task.c sched/numa: Introduce migrate_swap() 2013-10-09 12:40:46 +02:00
wait.c sched: Move wait code from core.c to wait.c 2013-11-06 07:49:18 +01:00