aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/kernel/process.c
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2012-03-11 11:59:27 -0400
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2012-03-11 11:59:28 -0400
commit4c1051e37a0e2a941115c6fb7ba08c318f25a0f9 (patch)
treef228f1a90c0d7abb8308f275d0906dd7d1588ba3 /arch/s390/kernel/process.c
parent8b646bd759086f6090fe27acf414c0b5faa737f4 (diff)
[S390] rework idle code
Whenever the cpu loads an enabled wait PSW it will appear as idle to the underlying host system. The code in default_idle calls vtime_stop_cpu which does the necessary voodoo to get the cpu time accounting right. The udelay code just loads an enabled wait PSW. To correct this rework the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts to entry[64].S, vtime_stop_cpu can now be called from anywhere and vtime_start_cpu is gone. The correction of the cpu time during wakeup from an enabled wait PSW is done with a critical section in entry[64].S. As vtime_start_cpu is gone, s390_idle_check can be removed as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/process.c')
-rw-r--r--arch/s390/kernel/process.c7
1 files changed, 1 insertions, 6 deletions
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index e795933eb2cb..78b3c149b8b6 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -77,13 +77,8 @@ static void default_idle(void)
local_irq_enable();
return;
}
- trace_hardirqs_on();
- /* Don't trace preempt off for idle. */
- stop_critical_timings();
- /* Stop virtual timer and halt the cpu. */
+ /* Halt the cpu and keep track of cpu time accounting. */
vtime_stop_cpu();
- /* Reenable preemption tracer. */
- start_critical_timings();
}
void cpu_idle(void)