From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
Instead of having the options_map use TRACEFS_OPTIONS_MAX as its index, have
the array extend by the elements, and use the new macros BUILD_BUG_ON() and
ARRAY_SIZE() to make sure that the array always is the same size as the
TRACEFS_OPTIONS_MAX.
No functional changes.
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
include/tracefs-local.h | 6 ++++++
src/tracefs-tools.c | 5 ++++-
2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/include/tracefs-local.h b/include/tracefs-local.h
index 3a7ec32a8853..187870e7c491 100644
--- a/include/tracefs-local.h
+++ b/include/tracefs-local.h
@@ -8,6 +8,12 @@
#define __hidden __attribute__((visibility ("hidden")))
+#define ARRAY_SIZE(array) (sizeof(array) / sizeof((array)[0]))
+
+/* Will cause a division by zero warning if cond is true */
+#define BUILD_BUG_ON(cond) \
+ do { if (!(1/!(cond))) { } } while (0)
+
/* Can be overridden */
void warning(const char *fmt, ...);
diff --git a/src/tracefs-tools.c b/src/tracefs-tools.c
index 6e7fce53cef1..7f69cde93115 100644
--- a/src/tracefs-tools.c
+++ b/src/tracefs-tools.c
@@ -19,7 +19,7 @@
#define TRACE_CTRL "tracing_on"
-static const char * const options_map[TRACEFS_OPTION_MAX] = {
+static const char * const options_map[] = {
"unknown", "annotate", "bin", "blk_cgname", "blk_cgroup", "blk_classic",
"block", "context-info", "disable_on_free", "display-graph", "event-fork",
"funcgraph-abstime", "funcgraph-cpu", "funcgraph-duration", "funcgraph-irqs",
@@ -132,6 +132,9 @@ int tracefs_trace_off_fd(int fd)
*/
const char *tracefs_option_name(enum tracefs_option_id id)
{
+ /* Make sure options map contains all the options */
+ BUILD_BUG_ON(ARRAY_SIZE(options_map) != TRACEFS_OPTION_MAX);
+
if (id < TRACEFS_OPTION_MAX)
return options_map[id];
--
2.29.2
|