Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux...

[pandora-kernel.git] / kernel / perf_counter.c

diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 534e20d..d7cbc57 100644 (file)
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -50,7 +50,7 @@ static atomic_t nr_task_counters __read_mostly;
  *  1 - disallow cpu counters to unpriv
  *  2 - disallow kernel profiling to unpriv
  */
-int sysctl_perf_counter_paranoid __read_mostly;
+int sysctl_perf_counter_paranoid __read_mostly = 1;
 
 static inline bool perf_paranoid_cpu(void)
 {
@@ -1503,10 +1503,21 @@ static void perf_counter_enable_on_exec(struct task_struct *task)
  */
 static void __perf_counter_read(void *info)
 {
+       struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
        struct perf_counter *counter = info;
        struct perf_counter_context *ctx = counter->ctx;
        unsigned long flags;
 
+       /*
+        * If this is a task context, we need to check whether it is
+        * the current task context of this cpu.  If not it has been
+        * scheduled out before the smp call arrived.  In that case
+        * counter->count would have been updated to a recent sample
+        * when the counter was scheduled out.
+        */
+       if (ctx->task && cpuctx->task_ctx != ctx)
+               return;
+
        local_irq_save(flags);
        if (ctx->is_active)
                update_context_time(ctx);
@@ -1780,7 +1791,7 @@ static int perf_counter_read_group(struct perf_counter *counter,
        size += err;
 
        list_for_each_entry(sub, &leader->sibling_list, list_entry) {
-               err = perf_counter_read_entry(counter, read_format,
+               err = perf_counter_read_entry(sub, read_format,
                                buf + size);
                if (err < 0)
                        return err;
@@ -2008,6 +2019,10 @@ int perf_counter_task_disable(void)
        return 0;
 }
 
+#ifndef PERF_COUNTER_INDEX_OFFSET
+# define PERF_COUNTER_INDEX_OFFSET 0
+#endif
+
 static int perf_counter_index(struct perf_counter *counter)
 {
        if (counter->state != PERF_COUNTER_STATE_ACTIVE)
@@ -4051,6 +4066,7 @@ perf_counter_alloc(struct perf_counter_attr *attr,
        hwc->sample_period = attr->sample_period;
        if (attr->freq && attr->sample_freq)
                hwc->sample_period = 1;
+       hwc->last_period = hwc->sample_period;
 
        atomic64_set(&hwc->period_left, hwc->sample_period);