Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86: Try to handle unknown nmis with an enabled PMU
  perf, x86: Fix handle_irq return values
  perf, x86: Fix accidentally ack'ing a second event on intel perf counter
  oprofile, x86: fix init_sysfs() function stub
  lockup_detector: Sync touch_*_watchdog back to old semantics
  tracing: Fix a race in function profile
  oprofile, x86: fix init_sysfs error handling
  perf_events: Fix time tracking for events with pid != -1 and cpu != -1
  perf: Initialize callchains roots's childen hits
  oprofile: fix crash when accessing freed task structs

kernel/perf_event.c

@@ -402,11 +402,31 @@ static void perf_group_detach(struct perf_event *event)
 	}
 }
 
+static inline int
+event_filter_match(struct perf_event *event)
+{
+	return event->cpu == -1 || event->cpu == smp_processor_id();
+}
+
 static void
 event_sched_out(struct perf_event *event,
 		  struct perf_cpu_context *cpuctx,
 		  struct perf_event_context *ctx)
 {
+	u64 delta;
+	/*
+	 * An event which could not be activated because of
+	 * filter mismatch still needs to have its timings
+	 * maintained, otherwise bogus information is return
+	 * via read() for time_enabled, time_running:
+	 */
+	if (event->state == PERF_EVENT_STATE_INACTIVE
+	    && !event_filter_match(event)) {
+		delta = ctx->time - event->tstamp_stopped;
+		event->tstamp_running += delta;
+		event->tstamp_stopped = ctx->time;
+	}
+
 	if (event->state != PERF_EVENT_STATE_ACTIVE)
 		return;
 
@@ -432,9 +452,7 @@ group_sched_out(struct perf_event *group_event,
 		struct perf_event_context *ctx)
 {
 	struct perf_event *event;
-
-	if (group_event->state != PERF_EVENT_STATE_ACTIVE)
-		return;
+	int state = group_event->state;
 
 	event_sched_out(group_event, cpuctx, ctx);
 
@@ -444,7 +462,7 @@ group_sched_out(struct perf_event *group_event,
 	list_for_each_entry(event, &group_event->sibling_list, group_entry)
 		event_sched_out(event, cpuctx, ctx);
 
-	if (group_event->attr.exclusive)
+	if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive)
 		cpuctx->exclusive = 0;
 }
 

kernel/trace/ftrace.c

@@ -381,12 +381,19 @@ static int function_stat_show(struct seq_file *m, void *v)
 {
 	struct ftrace_profile *rec = v;
 	char str[KSYM_SYMBOL_LEN];
+	int ret = 0;
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-	static DEFINE_MUTEX(mutex);
 	static struct trace_seq s;
 	unsigned long long avg;
 	unsigned long long stddev;
 #endif
+	mutex_lock(&ftrace_profile_lock);
+
+	/* we raced with function_profile_reset() */
+	if (unlikely(rec->counter == 0)) {
+		ret = -EBUSY;
+		goto out;
+	}
 
 	kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
 	seq_printf(m, "  %-30.30s  %10lu", str, rec->counter);
@@ -408,7 +415,6 @@ static int function_stat_show(struct seq_file *m, void *v)
 		do_div(stddev, (rec->counter - 1) * 1000);
 	}
 
-	mutex_lock(&mutex);
 	trace_seq_init(&s);
 	trace_print_graph_duration(rec->time, &s);
 	trace_seq_puts(&s, "    ");
@@ -416,11 +422,12 @@ static int function_stat_show(struct seq_file *m, void *v)
 	trace_seq_puts(&s, "    ");
 	trace_print_graph_duration(stddev, &s);
 	trace_print_seq(m, &s);
-	mutex_unlock(&mutex);
 #endif
 	seq_putc(m, '\n');
+out:
+	mutex_unlock(&ftrace_profile_lock);
 
-	return 0;
+	return ret;
 }
 
 static void ftrace_profile_reset(struct ftrace_profile_stat *stat)

kernel/watchdog.c

@@ -122,7 +122,7 @@ static void __touch_watchdog(void)
 
 void touch_softlockup_watchdog(void)
 {
-	__get_cpu_var(watchdog_touch_ts) = 0;
+	__raw_get_cpu_var(watchdog_touch_ts) = 0;
 }
 EXPORT_SYMBOL(touch_softlockup_watchdog);
 
@@ -142,7 +142,14 @@ void touch_all_softlockup_watchdogs(void)
 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 void touch_nmi_watchdog(void)
 {
-	__get_cpu_var(watchdog_nmi_touch) = true;
+	if (watchdog_enabled) {
+		unsigned cpu;
+
+		for_each_present_cpu(cpu) {
+			if (per_cpu(watchdog_nmi_touch, cpu) != true)
+				per_cpu(watchdog_nmi_touch, cpu) = true;
+		}
+	}
 	touch_softlockup_watchdog();
 }
 EXPORT_SYMBOL(touch_nmi_watchdog);
@@ -433,6 +440,9 @@ static int watchdog_enable(int cpu)
 		wake_up_process(p);
 	}
 
+	/* if any cpu succeeds, watchdog is considered enabled for the system */
+	watchdog_enabled = 1;
+
 	return 0;
 }
 
@@ -455,9 +465,6 @@ static void watchdog_disable(int cpu)
 		per_cpu(softlockup_watchdog, cpu) = NULL;
 		kthread_stop(p);
 	}
-
-	/* if any cpu succeeds, watchdog is considered enabled for the system */
-	watchdog_enabled = 1;
 }
 
 static void watchdog_enable_all_cpus(void)