tracing: Simplify trace_option_write()
- remove duplicate code inside trace_options_write()
- extract duplicate code in trace_options_write() and set_tracer_option()
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4B1DC532.9010802@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 898409d..0507600 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2343,29 +2343,13 @@
return 0;
}
-/* Try to assign a tracer specific option */
-static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
+static int __set_tracer_option(struct tracer *trace,
+ struct tracer_flags *tracer_flags,
+ struct tracer_opt *opts, int neg)
{
- struct tracer_flags *tracer_flags = trace->flags;
- struct tracer_opt *opts = NULL;
- int ret = 0, i = 0;
- int len;
+ int ret;
- for (i = 0; tracer_flags->opts[i].name; i++) {
- opts = &tracer_flags->opts[i];
- len = strlen(opts->name);
-
- if (strncmp(cmp, opts->name, len) == 0) {
- ret = trace->set_flag(tracer_flags->val,
- opts->bit, !neg);
- break;
- }
- }
- /* Not found */
- if (!tracer_flags->opts[i].name)
- return -EINVAL;
-
- /* Refused to handle */
+ ret = trace->set_flag(tracer_flags->val, opts->bit, !neg);
if (ret)
return ret;
@@ -2373,10 +2357,27 @@
tracer_flags->val &= ~opts->bit;
else
tracer_flags->val |= opts->bit;
-
return 0;
}
+/* Try to assign a tracer specific option */
+static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
+{
+ struct tracer_flags *tracer_flags = trace->flags;
+ struct tracer_opt *opts = NULL;
+ int i;
+
+ for (i = 0; tracer_flags->opts[i].name; i++) {
+ opts = &tracer_flags->opts[i];
+
+ if (strcmp(cmp, opts->name) == 0)
+ return __set_tracer_option(trace, trace->flags,
+ opts, neg);
+ }
+
+ return -EINVAL;
+}
+
static void set_tracer_flags(unsigned int mask, int enabled)
{
/* do nothing if flag is already set */
@@ -2394,7 +2395,7 @@
size_t cnt, loff_t *ppos)
{
char buf[64];
- char *cmp = buf;
+ char *cmp;
int neg = 0;
int ret;
int i;
@@ -2406,16 +2407,15 @@
return -EFAULT;
buf[cnt] = 0;
+ cmp = strstrip(buf);
- if (strncmp(buf, "no", 2) == 0) {
+ if (strncmp(cmp, "no", 2) == 0) {
neg = 1;
cmp += 2;
}
for (i = 0; trace_options[i]; i++) {
- int len = strlen(trace_options[i]);
-
- if (strncmp(cmp, trace_options[i], len) == 0) {
+ if (strcmp(cmp, trace_options[i]) == 0) {
set_tracer_flags(1 << i, !neg);
break;
}
@@ -3927,39 +3927,16 @@
if (ret < 0)
return ret;
- ret = 0;
- switch (val) {
- case 0:
- /* do nothing if already cleared */
- if (!(topt->flags->val & topt->opt->bit))
- break;
-
- mutex_lock(&trace_types_lock);
- if (current_trace->set_flag)
- ret = current_trace->set_flag(topt->flags->val,
- topt->opt->bit, 0);
- mutex_unlock(&trace_types_lock);
- if (ret)
- return ret;
- topt->flags->val &= ~topt->opt->bit;
- break;
- case 1:
- /* do nothing if already set */
- if (topt->flags->val & topt->opt->bit)
- break;
-
- mutex_lock(&trace_types_lock);
- if (current_trace->set_flag)
- ret = current_trace->set_flag(topt->flags->val,
- topt->opt->bit, 1);
- mutex_unlock(&trace_types_lock);
- if (ret)
- return ret;
- topt->flags->val |= topt->opt->bit;
- break;
-
- default:
+ if (val != 0 && val != 1)
return -EINVAL;
+
+ if (!!(topt->flags->val & topt->opt->bit) != val) {
+ mutex_lock(&trace_types_lock);
+ ret = __set_tracer_option(current_trace, topt->flags,
+ topt->opt, val);
+ mutex_unlock(&trace_types_lock);
+ if (ret)
+ return ret;
}
*ppos += cnt;