tracing: Add the constant count for branch tracer
The unlikely/likely branch profiler now gets called even if the if statement
is a constant (always goes in one direction without a compare). Add a value
to denote this in the likely/unlikely tracer as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index fd483d7..4d8fdf3 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -27,7 +27,7 @@ static DEFINE_MUTEX(branch_tracing_mutex);
static struct trace_array *branch_tracer;
static void
-probe_likely_condition(struct ftrace_branch_data *f, int val, int expect)
+probe_likely_condition(struct ftrace_likely_data *f, int val, int expect)
{
struct trace_event_call *call = &event_branch;
struct trace_array *tr = branch_tracer;
@@ -68,16 +68,17 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect)
entry = ring_buffer_event_data(event);
/* Strip off the path, only save the file */
- p = f->file + strlen(f->file);
- while (p >= f->file && *p != '/')
+ p = f->data.file + strlen(f->data.file);
+ while (p >= f->data.file && *p != '/')
p--;
p++;
- strncpy(entry->func, f->func, TRACE_FUNC_SIZE);
+ strncpy(entry->func, f->data.func, TRACE_FUNC_SIZE);
strncpy(entry->file, p, TRACE_FILE_SIZE);
entry->func[TRACE_FUNC_SIZE] = 0;
entry->file[TRACE_FILE_SIZE] = 0;
- entry->line = f->line;
+ entry->constant = f->constant;
+ entry->line = f->data.line;
entry->correct = val == expect;
if (!call_filter_check_discard(call, entry, buffer, event))
@@ -89,7 +90,7 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect)
}
static inline
-void trace_likely_condition(struct ftrace_branch_data *f, int val, int expect)
+void trace_likely_condition(struct ftrace_likely_data *f, int val, int expect)
{
if (!branch_tracing_enabled)
return;
@@ -195,7 +196,7 @@ core_initcall(init_branch_tracer);
#else
static inline
-void trace_likely_condition(struct ftrace_branch_data *f, int val, int expect)
+void trace_likely_condition(struct ftrace_likely_data *f, int val, int expect)
{
}
#endif /* CONFIG_BRANCH_TRACER */
@@ -214,7 +215,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
* conditions that the recursive nightmare that exists is too
* much to try to get working. At least for now.
*/
- trace_likely_condition(&f->data, val, expect);
+ trace_likely_condition(f, val, expect);
/* FIXME: Make this atomic! */
if (val == expect)
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index eb7396b..c203ac4 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -328,11 +328,13 @@ FTRACE_ENTRY(branch, trace_branch,
__array( char, func, TRACE_FUNC_SIZE+1 )
__array( char, file, TRACE_FILE_SIZE+1 )
__field( char, correct )
+ __field( char, constant )
),
- F_printk("%u:%s:%s (%u)",
+ F_printk("%u:%s:%s (%u)%s",
__entry->line,
- __entry->func, __entry->file, __entry->correct),
+ __entry->func, __entry->file, __entry->correct,
+ __entry->constant ? " CONSTANT" : ""),
FILTER_OTHER
);