diff options
| author | Steven Rostedt <srostedt@redhat.com> | 2012-08-09 22:26:46 -0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-03-07 10:06:06 -0500 |
| commit | 35bb4399bd0ef16b8a57fccea0047d98b6b0e7fb (patch) | |
| tree | 16b340bd7b6d1e17e9d78d7d3ea88141cf2e3905 /kernel/trace/trace_output.c | |
| parent | 1d6bae966e90134bcfd7807b8f9488d55198de91 (diff) | |
tracing: Move event storage for array from macro to standalone function
The code that shows array fields for events is defined for all events.
This can add up quite a bit when you have over 500 events.
By making helper functions in the core kernel to do the work
instead, we can shrink the size of the kernel down a bit.
With a kernel configured with 502 events, the change in size was:
text data bss dec hex filename
12990946 1913568 9785344 24689858 178bcc2 /tmp/vmlinux
12987390 1913504 9785344 24686238 178ae9e /tmp/vmlinux.patched
That's a total of 3556 bytes, which comes down to 7 bytes per event.
Although it's not much, this code is just called at initialization of
the events.
Link: http://lkml.kernel.org/r/20120810034708.084036335@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_output.c')
| -rw-r--r-- | kernel/trace/trace_output.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index ca0e79e2abaa..ee8d74840b88 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -20,6 +20,10 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly; static int next_event_type = __TRACE_LAST_TYPE + 1; +#define EVENT_STORAGE_SIZE 128 +static DEFINE_MUTEX(event_storage_mutex); +static char event_storage[EVENT_STORAGE_SIZE]; + int trace_print_seq(struct seq_file *m, struct trace_seq *s) { int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; @@ -470,6 +474,23 @@ int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...) } EXPORT_SYMBOL_GPL(ftrace_output_call); +int ftrace_event_define_field(struct ftrace_event_call *call, + char *type, int len, char *item, int offset, + int field_size, int sign, int filter) +{ + int ret; + + mutex_lock(&event_storage_mutex); + snprintf(event_storage, sizeof(event_storage), + "%s[%d]", type, len); + ret = trace_define_field(call, event_storage, item, offset, + field_size, sign, filter); + mutex_unlock(&event_storage_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(ftrace_event_define_field); + #ifdef CONFIG_KRETPROBES static inline const char *kretprobed(const char *name) { |