[S390] Convert s390 to GENERIC_CLOCKEVENTS.
This way we get rid of s390's NO_IDLE_HZ and use the generic dynticks
variant instead. In addition we get high resolution timers for free.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c
index 70f2a86..eae21a8 100644
--- a/arch/s390/lib/delay.c
+++ b/arch/s390/lib/delay.c
@@ -34,7 +34,7 @@
*/
void __udelay(unsigned long usecs)
{
- u64 end, time, jiffy_timer = 0;
+ u64 end, time, old_cc = 0;
unsigned long flags, cr0, mask, dummy;
int irq_context;
@@ -43,8 +43,8 @@
local_bh_disable();
local_irq_save(flags);
if (raw_irqs_disabled_flags(flags)) {
- jiffy_timer = S390_lowcore.jiffy_timer;
- S390_lowcore.jiffy_timer = -1ULL - (4096 << 12);
+ old_cc = S390_lowcore.clock_comparator;
+ S390_lowcore.clock_comparator = -1ULL;
__ctl_store(cr0, 0, 0);
dummy = (cr0 & 0xffff00e0) | 0x00000800;
__ctl_load(dummy , 0, 0);
@@ -55,8 +55,8 @@
end = get_clock() + ((u64) usecs << 12);
do {
- time = end < S390_lowcore.jiffy_timer ?
- end : S390_lowcore.jiffy_timer;
+ time = end < S390_lowcore.clock_comparator ?
+ end : S390_lowcore.clock_comparator;
set_clock_comparator(time);
trace_hardirqs_on();
__load_psw_mask(mask);
@@ -65,10 +65,10 @@
if (raw_irqs_disabled_flags(flags)) {
__ctl_load(cr0, 0, 0);
- S390_lowcore.jiffy_timer = jiffy_timer;
+ S390_lowcore.clock_comparator = old_cc;
}
if (!irq_context)
_local_bh_enable();
- set_clock_comparator(S390_lowcore.jiffy_timer);
+ set_clock_comparator(S390_lowcore.clock_comparator);
local_irq_restore(flags);
}