ftrace, locking fix

should be an irq-safe lock ...

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fa13059..70f94fa 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -691,14 +691,15 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data,
        unsigned long ip, unsigned long parent_ip, unsigned long flags)
 {
        struct trace_entry *entry;
+       unsigned long irq_flags;
 
-       spin_lock(&data->lock);
+       spin_lock_irqsave(&data->lock, irq_flags);
        entry                   = tracing_get_trace_entry(tr, data);
        tracing_generic_entry_update(entry, flags);
        entry->type             = TRACE_FN;
        entry->fn.ip            = ip;
        entry->fn.parent_ip     = parent_ip;
-       spin_unlock(&data->lock);
+       spin_unlock_irqrestore(&data->lock, irq_flags);
 }
 
 notrace void
@@ -706,15 +707,16 @@ trace_special(struct trace_array *tr, struct trace_array_cpu *data,
              unsigned long arg1, unsigned long arg2, unsigned long arg3)
 {
        struct trace_entry *entry;
+       unsigned long irq_flags;
 
-       spin_lock(&data->lock);
+       spin_lock_irqsave(&data->lock, irq_flags);
        entry                   = tracing_get_trace_entry(tr, data);
        tracing_generic_entry_update(entry, 0);
        entry->type             = TRACE_SPECIAL;
        entry->special.arg1     = arg1;
        entry->special.arg2     = arg2;
        entry->special.arg3     = arg3;
-       spin_unlock(&data->lock);
+       spin_unlock_irqrestore(&data->lock, irq_flags);
 }
 
 notrace void
@@ -724,8 +726,9 @@ tracing_sched_switch_trace(struct trace_array *tr,
                           unsigned long flags)
 {
        struct trace_entry *entry;
+       unsigned long irq_flags;
 
-       spin_lock(&data->lock);
+       spin_lock_irqsave(&data->lock, irq_flags);
        entry                   = tracing_get_trace_entry(tr, data);
        tracing_generic_entry_update(entry, flags);
        entry->type             = TRACE_CTX;
@@ -734,7 +737,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
        entry->ctx.prev_state   = prev->state;
        entry->ctx.next_pid     = next->pid;
        entry->ctx.next_prio    = next->prio;
-       spin_unlock(&data->lock);
+       spin_unlock_irqrestore(&data->lock, irq_flags);
 }
 
 enum trace_file_type {