Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters into perfcounters/core

1 files changed, 46 insertions, 9 deletions

diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 37f771691f93..4c0dccb756ad 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -41,12 +41,20 @@ static DEFINE_MUTEX(perf_resource_mutex);
 extern __weak const struct hw_perf_counter_ops *
 hw_perf_counter_init(struct perf_counter *counter)
 {
-        return ERR_PTR(-EINVAL);
+        return NULL;
 }
 
 u64 __weak hw_perf_save_disable(void)           { return 0; }
 void __weak hw_perf_restore(u64 ctrl)           { barrier(); }
 void __weak hw_perf_counter_setup(void)         { barrier(); }
+int __weak hw_perf_group_sched_in(struct perf_counter *group_leader,
+               struct perf_cpu_context *cpuctx,
+               struct perf_counter_context *ctx, int cpu)
+{
+        return 0;
+}
+
+void __weak perf_counter_print_debug(void)      { }
 
 static void
 list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx)
@@ -341,6 +349,9 @@ group_sched_out(struct perf_counter *group_counter,
 {
         struct perf_counter *counter;
 
+        if (group_counter->state != PERF_COUNTER_STATE_ACTIVE)
+                return;
+
         counter_sched_out(group_counter, cpuctx, ctx);
 
         /*
@@ -354,15 +365,18 @@ void __perf_counter_sched_out(struct perf_counter_context *ctx,
                               struct perf_cpu_context *cpuctx)
 {
         struct perf_counter *counter;
+        u64 flags;
 
         if (likely(!ctx->nr_counters))
                 return;
 
         spin_lock(&ctx->lock);
+        flags = hw_perf_save_disable();
         if (ctx->nr_active) {
                 list_for_each_entry(counter, &ctx->counter_list, list_entry)
                         group_sched_out(counter, cpuctx, ctx);
         }
+        hw_perf_restore(flags);
         spin_unlock(&ctx->lock);
 }
 
@@ -402,7 +416,14 @@ group_sched_in(struct perf_counter *group_counter,
                int cpu)
 {
         struct perf_counter *counter, *partial_group;
-        int ret = 0;
+        int ret;
+
+        if (group_counter->state == PERF_COUNTER_STATE_OFF)
+                return 0;
+
+        ret = hw_perf_group_sched_in(group_counter, cpuctx, ctx, cpu);
+        if (ret)
+                return ret < 0 ? ret : 0;
 
         if (counter_sched_in(group_counter, cpuctx, ctx, cpu))
                 return -EAGAIN;
@@ -415,10 +436,9 @@ group_sched_in(struct perf_counter *group_counter,
                         partial_group = counter;
                         goto group_error;
                 }
-                ret = -EAGAIN;
         }
 
-        return ret;
+        return 0;
 
 group_error:
         /*
@@ -440,11 +460,13 @@ __perf_counter_sched_in(struct perf_counter_context *ctx,
                         struct perf_cpu_context *cpuctx, int cpu)
 {
         struct perf_counter *counter;
+        u64 flags;
 
         if (likely(!ctx->nr_counters))
                 return;
 
         spin_lock(&ctx->lock);
+        flags = hw_perf_save_disable();
         list_for_each_entry(counter, &ctx->counter_list, list_entry) {
                 /*
                  * Listen to the 'cpu' scheduling filter constraint
@@ -454,12 +476,13 @@ __perf_counter_sched_in(struct perf_counter_context *ctx,
                         continue;
 
                 /*
-                 * If we scheduled in a group atomically and
-                 * exclusively, break out:
+                 * If we scheduled in a group atomically and exclusively,
+                 * or if this group can't go on, break out:
                  */
                 if (group_sched_in(counter, cpuctx, ctx, cpu))
                         break;
         }
+        hw_perf_restore(flags);
         spin_unlock(&ctx->lock);
 }
 
@@ -928,18 +951,32 @@ static const struct file_operations perf_fops = {
 
 static int cpu_clock_perf_counter_enable(struct perf_counter *counter)
 {
+        int cpu = raw_smp_processor_id();
+
+        atomic64_set(&counter->hw.prev_count, cpu_clock(cpu));
         return 0;
 }
 
+static void cpu_clock_perf_counter_update(struct perf_counter *counter)
+{
+        int cpu = raw_smp_processor_id();
+        s64 prev;
+        u64 now;
+
+        now = cpu_clock(cpu);
+        prev = atomic64_read(&counter->hw.prev_count);
+        atomic64_set(&counter->hw.prev_count, now);
+        atomic64_add(now - prev, &counter->count);
+}
+
 static void cpu_clock_perf_counter_disable(struct perf_counter *counter)
 {
+        cpu_clock_perf_counter_update(counter);
 }
 
 static void cpu_clock_perf_counter_read(struct perf_counter *counter)
 {
-        int cpu = raw_smp_processor_id();
-
-        atomic64_set(&counter->count, cpu_clock(cpu));
+        cpu_clock_perf_counter_update(counter);
 }
 
 static const struct hw_perf_counter_ops perf_ops_cpu_clock = {