diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.c | 6 | ||||
| -rw-r--r-- | kernel/trace/trace_irqsoff.c | 27 |
2 files changed, 20 insertions, 13 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9175ce91b8f6..95966561ba3d 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -153,6 +153,7 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) memcpy(max_tr.data[i], data, sizeof(*data)); data->trace = save_trace; data->trace_pages = save_pages; + tracing_reset(data); } __update_max_tr(tr, tsk, cpu); @@ -183,6 +184,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) memcpy(max_tr.data[cpu], data, sizeof(*data)); data->trace = save_trace; data->trace_pages = save_pages; + tracing_reset(data); __update_max_tr(tr, tsk, cpu); spin_unlock(&ftrace_max_lock); @@ -877,6 +879,8 @@ print_lat_fmt(struct seq_file *m, struct trace_iterator *iter, entry->ctx.next_prio, comm); break; + default: + seq_printf(m, "Unknown type %d\n", entry->type); } } @@ -1625,7 +1629,6 @@ __init static int tracer_alloc_buffers(void) * round up a bit. */ global_trace.entries = ENTRIES_PER_PAGE; - max_tr.entries = global_trace.entries; pages++; while (global_trace.entries < trace_nr_entries) { @@ -1633,6 +1636,7 @@ __init static int tracer_alloc_buffers(void) break; pages++; } + max_tr.entries = global_trace.entries; pr_info("tracer: %d pages allocated for %ld", pages, trace_nr_entries); diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index bd3f88198308..74165f611f36 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -23,6 +23,8 @@ static int tracer_enabled __read_mostly; static DEFINE_PER_CPU(int, tracing_cpu); +static DEFINE_SPINLOCK(max_trace_lock); + enum { TRACER_IRQS_OFF = (1 << 1), TRACER_PREEMPT_OFF = (1 << 2), @@ -126,7 +128,7 @@ check_critical_timing(struct trace_array *tr, int cpu) { unsigned long latency, t0, t1; - cycle_t T0, T1, T2, delta; + cycle_t T0, T1, delta; unsigned long flags; /* @@ -142,20 +144,18 @@ check_critical_timing(struct trace_array *tr, if (!report_latency(delta)) goto out; - ftrace(tr, data, CALLER_ADDR0, parent_ip, flags); - /* - * Update the timestamp, because the trace entry above - * might change it (it can only get larger so the latency - * is fair to be reported): - */ - T2 = now(cpu); + spin_lock(&max_trace_lock); - delta = T2-T0; + /* check if we are still the max latency */ + if (!report_latency(delta)) + goto out_unlock; + + ftrace(tr, data, CALLER_ADDR0, parent_ip, flags); latency = nsecs_to_usecs(delta); if (data->critical_sequence != max_sequence) - goto out; + goto out_unlock; tracing_max_latency = delta; t0 = nsecs_to_usecs(T0); @@ -189,6 +189,9 @@ check_critical_timing(struct trace_array *tr, max_sequence++; +out_unlock: + spin_unlock(&max_trace_lock); + out: data->critical_sequence = max_sequence; data->preempt_timestamp = now(cpu); @@ -366,14 +369,14 @@ void notrace trace_preempt_off(unsigned long a0, unsigned long a1) static void start_irqsoff_tracer(struct trace_array *tr) { - tracer_enabled = 1; register_ftrace_function(&trace_ops); + tracer_enabled = 1; } static void stop_irqsoff_tracer(struct trace_array *tr) { - unregister_ftrace_function(&trace_ops); tracer_enabled = 0; + unregister_ftrace_function(&trace_ops); } static void __irqsoff_tracer_init(struct trace_array *tr) |