summaryrefslogtreecommitdiffstats
path: root/kernel/trace/ftrace.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2011-07-21 09:29:14 +0200
committerIngo Molnar <mingo@elte.hu>2011-07-21 09:29:21 +0200
commit492f73a303b488ffd67097b2351d54aa6e6c7c73 (patch)
tree6e6c16fbd628bb5eb577cfc70a488ca286563e58 /kernel/trace/ftrace.c
parenttracing, x86/irq: Do not trace arch_local_{*,irq_*}() functions (diff)
parentftrace: Fix regression where ftrace breaks when modules are loaded (diff)
downloadlinux-492f73a303b488ffd67097b2351d54aa6e6c7c73.tar.xz
linux-492f73a303b488ffd67097b2351d54aa6e6c7c73.zip
Merge branch 'perf/urgent' into perf/core
Merge reason: pick up the latest fixes - they won't make v3.0. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c42
1 files changed, 31 insertions, 11 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index c997f7371c65..a0e246e2cee3 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1732,10 +1732,36 @@ static cycle_t ftrace_update_time;
static unsigned long ftrace_update_cnt;
unsigned long ftrace_update_tot_cnt;
+static int ops_traces_mod(struct ftrace_ops *ops)
+{
+ struct ftrace_hash *hash;
+
+ hash = ops->filter_hash;
+ return !!(!hash || !hash->count);
+}
+
static int ftrace_update_code(struct module *mod)
{
struct dyn_ftrace *p;
cycle_t start, stop;
+ unsigned long ref = 0;
+
+ /*
+ * When adding a module, we need to check if tracers are
+ * currently enabled and if they are set to trace all functions.
+ * If they are, we need to enable the module functions as well
+ * as update the reference counts for those function records.
+ */
+ if (mod) {
+ struct ftrace_ops *ops;
+
+ for (ops = ftrace_ops_list;
+ ops != &ftrace_list_end; ops = ops->next) {
+ if (ops->flags & FTRACE_OPS_FL_ENABLED &&
+ ops_traces_mod(ops))
+ ref++;
+ }
+ }
start = ftrace_now(raw_smp_processor_id());
ftrace_update_cnt = 0;
@@ -1748,7 +1774,7 @@ static int ftrace_update_code(struct module *mod)
p = ftrace_new_addrs;
ftrace_new_addrs = p->newlist;
- p->flags = 0L;
+ p->flags = ref;
/*
* Do the initial record conversion from mcount jump
@@ -1771,7 +1797,7 @@ static int ftrace_update_code(struct module *mod)
* conversion puts the module to the correct state, thus
* passing the ftrace_make_call check.
*/
- if (ftrace_start_up) {
+ if (ftrace_start_up && ref) {
int failed = __ftrace_replace_code(p, 1);
if (failed) {
ftrace_bug(failed, p->ip);
@@ -2395,10 +2421,9 @@ ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod)
*/
static int
-ftrace_mod_callback(char *func, char *cmd, char *param, int enable)
+ftrace_mod_callback(struct ftrace_hash *hash,
+ char *func, char *cmd, char *param, int enable)
{
- struct ftrace_ops *ops = &global_ops;
- struct ftrace_hash *hash;
char *mod;
int ret = -EINVAL;
@@ -2418,11 +2443,6 @@ ftrace_mod_callback(char *func, char *cmd, char *param, int enable)
if (!strlen(mod))
return ret;
- if (enable)
- hash = ops->filter_hash;
- else
- hash = ops->notrace_hash;
-
ret = ftrace_match_module_records(hash, func, mod);
if (!ret)
ret = -EINVAL;
@@ -2748,7 +2768,7 @@ static int ftrace_process_regex(struct ftrace_hash *hash,
mutex_lock(&ftrace_cmd_mutex);
list_for_each_entry(p, &ftrace_commands, list) {
if (strcmp(p->name, command) == 0) {
- ret = p->func(func, command, next, enable);
+ ret = p->func(hash, func, command, next, enable);
goto out_unlock;
}
}