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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-22 12:51:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-22 12:51:28 -0700
commita9b011f5ac57cbaedb32a8149f3d39d7b2c1f0e0 (patch)
tree89c850cc9e2ed949f5fc3b99180cd6cb70db6160 /arch/s390/kernel/vtime.c
parentb5bdd43876e475724c662f99206f0349c67e33e6 (diff)
parentda6330fccc251db73945ee3eb6248985cf2574de (diff)
Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (22 commits) [S390] Update default configuration. [S390] kprobes: defer setting of ctlblk state [S390] Enable tick based perf_counter on s390. [S390] dasd: fix refcounting in dasd_change_state [S390] lockless idle time accounting [S390] driver_data access [S390] pm: fix build error for !SMP [S390] dasd_pm: fix stop flag handling [S390] ap/zcrypt: Suspend/Resume ap bus and zcrypt [S390] qdio: Sanitize do_QDIO sanity checks [S390] qdio: leave inbound SBALs primed [S390] qdio: merge AI tasklet into interrupt handler [S390] qdio: extract all primed SBALs at once [S390] qdio: fix check for running under z/VM [S390] qdio: move adapter interrupt tasklet code [S390] Use del_timer instead of del_timer_sync [S390] s390: remove DEBUG_MALLOC [S390] vt220 console: convert from bootmem to slab [S390] sclp console: convert from bootmem to slab [S390] 3270 console: convert from bootmem to slab ...
Diffstat (limited to 'arch/s390/kernel/vtime.c')
-rw-r--r--arch/s390/kernel/vtime.c27
1 files changed, 16 insertions, 11 deletions
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index c8eb7255332..c41bb0d416e 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -25,13 +25,9 @@
#include <asm/irq_regs.h>
#include <asm/cputime.h>
-static ext_int_info_t ext_int_info_timer;
-
static DEFINE_PER_CPU(struct vtimer_queue, virt_cpu_timer);
-DEFINE_PER_CPU(struct s390_idle_data, s390_idle) = {
- .lock = __SPIN_LOCK_UNLOCKED(s390_idle.lock)
-};
+DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
static inline __u64 get_vtimer(void)
{
@@ -153,11 +149,13 @@ void vtime_start_cpu(void)
vq->elapsed -= vq->idle - S390_lowcore.async_enter_timer;
}
- spin_lock(&idle->lock);
+ idle->sequence++;
+ smp_wmb();
idle->idle_time += idle_time;
idle->idle_enter = 0ULL;
idle->idle_count++;
- spin_unlock(&idle->lock);
+ smp_wmb();
+ idle->sequence++;
}
void vtime_stop_cpu(void)
@@ -244,15 +242,23 @@ cputime64_t s390_get_idle_time(int cpu)
{
struct s390_idle_data *idle;
unsigned long long now, idle_time, idle_enter;
+ unsigned int sequence;
idle = &per_cpu(s390_idle, cpu);
- spin_lock(&idle->lock);
+
now = get_clock();
+repeat:
+ sequence = idle->sequence;
+ smp_rmb();
+ if (sequence & 1)
+ goto repeat;
idle_time = 0;
idle_enter = idle->idle_enter;
if (idle_enter != 0ULL && idle_enter < now)
idle_time = now - idle_enter;
- spin_unlock(&idle->lock);
+ smp_rmb();
+ if (idle->sequence != sequence)
+ goto repeat;
return idle_time;
}
@@ -557,8 +563,7 @@ void init_cpu_vtimer(void)
void __init vtime_init(void)
{
/* request the cpu timer external interrupt */
- if (register_early_external_interrupt(0x1005, do_cpu_timer_interrupt,
- &ext_int_info_timer) != 0)
+ if (register_external_interrupt(0x1005, do_cpu_timer_interrupt))
panic("Couldn't request external interrupt 0x1005");
/* Enable cpu timer interrupts on the boot cpu. */