1 files changed, 8 insertions, 37 deletions

diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c
index 9587d3bcba55..eaca5ad803ff 100644
--- a/kernel/trace/trace_sysprof.c
+++ b/kernel/trace/trace_sysprof.c
@@ -196,27 +196,19 @@ static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer)
         return HRTIMER_RESTART;
 }
 
-static void start_stack_timer(int cpu)
+static void start_stack_timer(void *unused)
 {
-        struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu);
+        struct hrtimer *hrtimer = &__get_cpu_var(stack_trace_hrtimer);
 
         hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
         hrtimer->function = stack_trace_timer_fn;
-        hrtimer->cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
 
         hrtimer_start(hrtimer, ns_to_ktime(sample_period), HRTIMER_MODE_REL);
 }
 
 static void start_stack_timers(void)
 {
-        cpumask_t saved_mask = current->cpus_allowed;
-        int cpu;
-
-        for_each_online_cpu(cpu) {
-                set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
-                start_stack_timer(cpu);
-        }
-        set_cpus_allowed_ptr(current, &saved_mask);
+        on_each_cpu(start_stack_timer, NULL, 1);
 }
 
 static void stop_stack_timer(int cpu)
@@ -234,20 +226,10 @@ static void stop_stack_timers(void)
                 stop_stack_timer(cpu);
 }
 
-static void stack_reset(struct trace_array *tr)
-{
-        int cpu;
-
-        tr->time_start = ftrace_now(tr->cpu);
-
-        for_each_online_cpu(cpu)
-                tracing_reset(tr, cpu);
-}
-
 static void start_stack_trace(struct trace_array *tr)
 {
         mutex_lock(&sample_timer_lock);
-        stack_reset(tr);
+        tracing_reset_online_cpus(tr);
         start_stack_timers();
         tracer_enabled = 1;
         mutex_unlock(&sample_timer_lock);
@@ -261,27 +243,17 @@ static void stop_stack_trace(struct trace_array *tr)
         mutex_unlock(&sample_timer_lock);
 }
 
-static void stack_trace_init(struct trace_array *tr)
+static int stack_trace_init(struct trace_array *tr)
 {
         sysprof_trace = tr;
 
-        if (tr->ctrl)
-                start_stack_trace(tr);
+        start_stack_trace(tr);
+        return 0;
 }
 
 static void stack_trace_reset(struct trace_array *tr)
 {
-        if (tr->ctrl)
-                stop_stack_trace(tr);
-}
-
-static void stack_trace_ctrl_update(struct trace_array *tr)
-{
-        /* When starting a new trace, reset the buffers */
-        if (tr->ctrl)
-                start_stack_trace(tr);
-        else
-                stop_stack_trace(tr);
+        stop_stack_trace(tr);
 }
 
 static struct tracer stack_trace __read_mostly =
@@ -289,7 +261,6 @@ static struct tracer stack_trace __read_mostly =
         .name           = "sysprof",
         .init           = stack_trace_init,
         .reset          = stack_trace_reset,
-        .ctrl_update    = stack_trace_ctrl_update,
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_sysprof,
 #endif