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-rw-r--r--kernel/trace/ftrace.c30
1 files changed, 28 insertions, 2 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1c4c0b087e1d..ef9271b69b4f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1744,10 +1744,36 @@ 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;
@@ -1760,7 +1786,7 @@ 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
@@ -1783,7 +1809,7 @@ 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);