ftrace: trace scheduler rbtree

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

3 files changed, 6 insertions, 2 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 65d2c0a61ed4..06380dc1ebe0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -129,6 +129,7 @@ static const char *trace_options[] = {
         "bin",
         "block",
         "stacktrace",
+        "sched-tree",
         NULL
 };
 
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 75e237475674..a52015702a28 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -286,6 +286,7 @@ enum trace_iterator_flags {
         TRACE_ITER_BIN                  = 0x40,
         TRACE_ITER_BLOCK                = 0x80,
         TRACE_ITER_STACKTRACE           = 0x100,
+        TRACE_ITER_SCHED_TREE           = 0x200,
 };
 
 #endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index 12658b3f2b28..5555b906a666 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -36,7 +36,8 @@ ctx_switch_func(void *__rq, struct task_struct *prev, struct task_struct *next)
 
         if (likely(disabled == 1)) {
                 tracing_sched_switch_trace(tr, data, prev, next, flags);
-                ftrace_all_fair_tasks(__rq, tr, data);
+                if (trace_flags & TRACE_ITER_SCHED_TREE)
+                        ftrace_all_fair_tasks(__rq, tr, data);
         }
 
         atomic_dec(&data->disabled);
@@ -62,7 +63,8 @@ wakeup_func(void *__rq, struct task_struct *wakee, struct task_struct *curr)
 
         if (likely(disabled == 1)) {
                 tracing_sched_wakeup_trace(tr, data, wakee, curr, flags);
-                ftrace_all_fair_tasks(__rq, tr, data);
+                if (trace_flags & TRACE_ITER_SCHED_TREE)
+                        ftrace_all_fair_tasks(__rq, tr, data);
         }
 
         atomic_dec(&data->disabled);