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authorSteven Rostedt <srostedt@redhat.com>2012-08-09 22:26:46 -0400
committerSteven Rostedt <rostedt@goodmis.org>2014-03-07 10:06:06 -0500
commit35bb4399bd0ef16b8a57fccea0047d98b6b0e7fb (patch)
tree16b340bd7b6d1e17e9d78d7d3ea88141cf2e3905 /kernel/trace/trace_output.c
parent1d6bae966e90134bcfd7807b8f9488d55198de91 (diff)
downloadlinux-35bb4399bd0ef16b8a57fccea0047d98b6b0e7fb.tar.bz2
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.c21
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)
{