perf_counter: Rework the perf counter disable/enable

[mv-sheeva.git] / arch / powerpc / kernel / perf_counter.c

diff --git a/arch/powerpc/kernel/perf_counter.c b/arch/powerpc/kernel/perf_counter.c
index 15cdc8e67229614e915cd82f3088f62f9b7ba783..bb1b463c1361bc8f638e01a90620f2e0bc08749e 100644 (file)
--- a/arch/powerpc/kernel/perf_counter.c
+++ b/arch/powerpc/kernel/perf_counter.c
@@ -386,7 +386,7 @@ static void write_mmcr0(struct cpu_hw_counters *cpuhw, unsigned long mmcr0)
  * Disable all counters to prevent PMU interrupts and to allow
  * counters to be added or removed.
  */
-u64 hw_perf_save_disable(void)
+void hw_perf_disable(void)
 {
        struct cpu_hw_counters *cpuhw;
        unsigned long ret;
@@ -428,7 +428,6 @@ u64 hw_perf_save_disable(void)
                mb();
        }
        local_irq_restore(flags);
-       return ret;
 }
 
 /*
@@ -436,7 +435,7 @@ u64 hw_perf_save_disable(void)
  * If we were previously disabled and counters were added, then
  * put the new config on the PMU.
  */
-void hw_perf_restore(u64 disable)
+void hw_perf_enable(void)
 {
        struct perf_counter *counter;
        struct cpu_hw_counters *cpuhw;
@@ -448,9 +447,12 @@ void hw_perf_restore(u64 disable)
        int n_lim;
        int idx;
 
-       if (disable)
-               return;
        local_irq_save(flags);
+       if (!cpuhw->disabled) {
+               local_irq_restore(flags);
+               return;
+       }
+
        cpuhw = &__get_cpu_var(cpu_hw_counters);
        cpuhw->disabled = 0;
 
@@ -649,19 +651,18 @@ int hw_perf_group_sched_in(struct perf_counter *group_leader,
 /*
  * Add a counter to the PMU.
  * If all counters are not already frozen, then we disable and
- * re-enable the PMU in order to get hw_perf_restore to do the
+ * re-enable the PMU in order to get hw_perf_enable to do the
  * actual work of reconfiguring the PMU.
  */
 static int power_pmu_enable(struct perf_counter *counter)
 {
        struct cpu_hw_counters *cpuhw;
        unsigned long flags;
-       u64 pmudis;
        int n0;
        int ret = -EAGAIN;
 
        local_irq_save(flags);
-       pmudis = hw_perf_save_disable();
+       perf_disable();
 
        /*
         * Add the counter to the list (if there is room)
@@ -685,7 +686,7 @@ static int power_pmu_enable(struct perf_counter *counter)
 
        ret = 0;
  out:
-       hw_perf_restore(pmudis);
+       perf_enable();
        local_irq_restore(flags);
        return ret;
 }
@@ -697,11 +698,10 @@ static void power_pmu_disable(struct perf_counter *counter)
 {
        struct cpu_hw_counters *cpuhw;
        long i;
-       u64 pmudis;
        unsigned long flags;
 
        local_irq_save(flags);
-       pmudis = hw_perf_save_disable();
+       perf_disable();
 
        power_pmu_read(counter);
 
@@ -735,7 +735,7 @@ static void power_pmu_disable(struct perf_counter *counter)
                cpuhw->mmcr[0] &= ~(MMCR0_PMXE | MMCR0_FCECE);
        }
 
-       hw_perf_restore(pmudis);
+       perf_enable();
        local_irq_restore(flags);
 }