Merge branch 'topic/misc' into for-linus

[safe/jmp/linux-2.6] / kernel / trace / trace_irqsoff.c

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 7c2e326..2974bc7 100644 (file)
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -1,5 +1,5 @@
 /*
- * trace irqs off criticall timings
+ * trace irqs off critical timings
  *
  * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
  * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
@@ -32,6 +32,8 @@ enum {
 
 static int trace_type __read_mostly;
 
+static int save_lat_flag;
+
 #ifdef CONFIG_PREEMPT_TRACER
 static inline int
 preempt_trace(void)
@@ -95,7 +97,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
        disabled = atomic_inc_return(&data->disabled);
 
        if (likely(disabled == 1))
-               trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+               trace_function(tr, ip, parent_ip, flags, preempt_count());
 
        atomic_dec(&data->disabled);
 }
@@ -127,15 +129,10 @@ check_critical_timing(struct trace_array *tr,
                      unsigned long parent_ip,
                      int cpu)
 {
-       unsigned long latency, t0, t1;
        cycle_t T0, T1, delta;
        unsigned long flags;
        int pc;
 
-       /*
-        * usecs conversion is slow so we try to delay the conversion
-        * as long as possible:
-        */
        T0 = data->preempt_timestamp;
        T1 = ftrace_now(cpu);
        delta = T1-T0;
@@ -153,20 +150,19 @@ check_critical_timing(struct trace_array *tr,
        if (!report_latency(delta))
                goto out_unlock;
 
-       trace_function(tr, data, CALLER_ADDR0, parent_ip, flags, pc);
-
-       latency = nsecs_to_usecs(delta);
+       trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
+       /* Skip 5 functions to get to the irq/preempt enable function */
+       __trace_stack(tr, flags, 5, pc);
 
        if (data->critical_sequence != max_sequence)
                goto out_unlock;
 
-       tracing_max_latency = delta;
-       t0 = nsecs_to_usecs(T0);
-       t1 = nsecs_to_usecs(T1);
-
        data->critical_end = parent_ip;
 
-       update_max_tr_single(tr, current, cpu);
+       if (likely(!is_tracing_stopped())) {
+               tracing_max_latency = delta;
+               update_max_tr_single(tr, current, cpu);
+       }
 
        max_sequence++;
 
@@ -176,8 +172,7 @@ out_unlock:
 out:
        data->critical_sequence = max_sequence;
        data->preempt_timestamp = ftrace_now(cpu);
-       tracing_reset(tr, cpu);
-       trace_function(tr, data, CALLER_ADDR0, parent_ip, flags, pc);
+       trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
 }
 
 static inline void
@@ -206,11 +201,10 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
        data->critical_sequence = max_sequence;
        data->preempt_timestamp = ftrace_now(cpu);
        data->critical_start = parent_ip ? : ip;
-       tracing_reset(tr, cpu);
 
        local_save_flags(flags);
 
-       trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+       trace_function(tr, ip, parent_ip, flags, preempt_count());
 
        per_cpu(tracing_cpu, cpu) = 1;
 
@@ -244,7 +238,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip)
        atomic_inc(&data->disabled);
 
        local_save_flags(flags);
-       trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+       trace_function(tr, ip, parent_ip, flags, preempt_count());
        check_critical_timing(tr, data, parent_ip ? : ip, cpu);
        data->critical_start = 0;
        atomic_dec(&data->disabled);
@@ -353,66 +347,50 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
 }
 #endif /* CONFIG_PREEMPT_TRACER */
 
-/*
- * save_tracer_enabled is used to save the state of the tracer_enabled
- * variable when we disable it when we open a trace output file.
- */
-static int save_tracer_enabled;
-
 static void start_irqsoff_tracer(struct trace_array *tr)
 {
        register_ftrace_function(&trace_ops);
-       if (tracing_is_enabled()) {
+       if (tracing_is_enabled())
                tracer_enabled = 1;
-               save_tracer_enabled = 1;
-       } else {
+       else
                tracer_enabled = 0;
-               save_tracer_enabled = 0;
-       }
 }
 
 static void stop_irqsoff_tracer(struct trace_array *tr)
 {
        tracer_enabled = 0;
-       save_tracer_enabled = 0;
        unregister_ftrace_function(&trace_ops);
 }
 
 static void __irqsoff_tracer_init(struct trace_array *tr)
 {
+       save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT;
+       trace_flags |= TRACE_ITER_LATENCY_FMT;
+
+       tracing_max_latency = 0;
        irqsoff_trace = tr;
        /* make sure that the tracer is visible */
        smp_wmb();
+       tracing_reset_online_cpus(tr);
        start_irqsoff_tracer(tr);
 }
 
 static void irqsoff_tracer_reset(struct trace_array *tr)
 {
        stop_irqsoff_tracer(tr);
+
+       if (!save_lat_flag)
+               trace_flags &= ~TRACE_ITER_LATENCY_FMT;
 }
 
 static void irqsoff_tracer_start(struct trace_array *tr)
 {
        tracer_enabled = 1;
-       save_tracer_enabled = 1;
 }
 
 static void irqsoff_tracer_stop(struct trace_array *tr)
 {
        tracer_enabled = 0;
-       save_tracer_enabled = 0;
-}
-
-static void irqsoff_tracer_open(struct trace_iterator *iter)
-{
-       /* stop the trace while dumping */
-       tracer_enabled = 0;
-}
-
-static void irqsoff_tracer_close(struct trace_iterator *iter)
-{
-       /* restart tracing */
-       tracer_enabled = save_tracer_enabled;
 }
 
 #ifdef CONFIG_IRQSOFF_TRACER
@@ -430,8 +408,6 @@ static struct tracer irqsoff_tracer __read_mostly =
        .reset          = irqsoff_tracer_reset,
        .start          = irqsoff_tracer_start,
        .stop           = irqsoff_tracer_stop,
-       .open           = irqsoff_tracer_open,
-       .close          = irqsoff_tracer_close,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_irqsoff,
@@ -458,8 +434,6 @@ static struct tracer preemptoff_tracer __read_mostly =
        .reset          = irqsoff_tracer_reset,
        .start          = irqsoff_tracer_start,
        .stop           = irqsoff_tracer_stop,
-       .open           = irqsoff_tracer_open,
-       .close          = irqsoff_tracer_close,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_preemptoff,
@@ -488,8 +462,6 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
        .reset          = irqsoff_tracer_reset,
        .start          = irqsoff_tracer_start,
        .stop           = irqsoff_tracer_stop,
-       .open           = irqsoff_tracer_open,
-       .close          = irqsoff_tracer_close,
        .print_max      = 1,
 #ifdef CONFIG_FTRACE_SELFTEST
        .selftest    = trace_selftest_startup_preemptirqsoff,