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-rw-r--r--kernel/trace/ftrace.c87
1 files changed, 72 insertions, 15 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8ce9eefc5bb..a6d098c6df3 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2169,12 +2169,57 @@ 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)
+static inline int ops_traces_mod(struct ftrace_ops *ops)
{
- struct ftrace_hash *hash;
+ /*
+ * Filter_hash being empty will default to trace module.
+ * But notrace hash requires a test of individual module functions.
+ */
+ return ftrace_hash_empty(ops->filter_hash) &&
+ ftrace_hash_empty(ops->notrace_hash);
+}
+
+/*
+ * Check if the current ops references the record.
+ *
+ * If the ops traces all functions, then it was already accounted for.
+ * If the ops does not trace the current record function, skip it.
+ * If the ops ignores the function via notrace filter, skip it.
+ */
+static inline bool
+ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
+{
+ /* If ops isn't enabled, ignore it */
+ if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
+ return 0;
+
+ /* If ops traces all mods, we already accounted for it */
+ if (ops_traces_mod(ops))
+ return 0;
+
+ /* The function must be in the filter */
+ if (!ftrace_hash_empty(ops->filter_hash) &&
+ !ftrace_lookup_ip(ops->filter_hash, rec->ip))
+ return 0;
+
+ /* If in notrace hash, we ignore it too */
+ if (ftrace_lookup_ip(ops->notrace_hash, rec->ip))
+ return 0;
+
+ return 1;
+}
+
+static int referenced_filters(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *ops;
+ int cnt = 0;
- hash = ops->filter_hash;
- return ftrace_hash_empty(hash);
+ for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) {
+ if (ops_references_rec(ops, rec))
+ cnt++;
+ }
+
+ return cnt;
}
static int ftrace_update_code(struct module *mod)
@@ -2183,6 +2228,7 @@ static int ftrace_update_code(struct module *mod)
struct dyn_ftrace *p;
cycle_t start, stop;
unsigned long ref = 0;
+ bool test = false;
int i;
/*
@@ -2196,9 +2242,12 @@ static int ftrace_update_code(struct module *mod)
for (ops = ftrace_ops_list;
ops != &ftrace_list_end; ops = ops->next) {
- if (ops->flags & FTRACE_OPS_FL_ENABLED &&
- ops_traces_mod(ops))
- ref++;
+ if (ops->flags & FTRACE_OPS_FL_ENABLED) {
+ if (ops_traces_mod(ops))
+ ref++;
+ else
+ test = true;
+ }
}
}
@@ -2208,12 +2257,16 @@ static int ftrace_update_code(struct module *mod)
for (pg = ftrace_new_pgs; pg; pg = pg->next) {
for (i = 0; i < pg->index; i++) {
+ int cnt = ref;
+
/* If something went wrong, bail without enabling anything */
if (unlikely(ftrace_disabled))
return -1;
p = &pg->records[i];
- p->flags = ref;
+ if (test)
+ cnt += referenced_filters(p);
+ p->flags = cnt;
/*
* Do the initial record conversion from mcount jump
@@ -2233,7 +2286,7 @@ 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 && ref) {
+ if (ftrace_start_up && cnt) {
int failed = __ftrace_replace_code(p, 1);
if (failed)
ftrace_bug(failed, p->ip);
@@ -3384,6 +3437,12 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
return add_hash_entry(hash, ip);
}
+static void ftrace_ops_update_code(struct ftrace_ops *ops)
+{
+ if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled)
+ ftrace_run_update_code(FTRACE_UPDATE_CALLS);
+}
+
static int
ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
unsigned long ip, int remove, int reset, int enable)
@@ -3426,9 +3485,8 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
mutex_lock(&ftrace_lock);
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
- if (!ret && ops->flags & FTRACE_OPS_FL_ENABLED
- && ftrace_enabled)
- ftrace_run_update_code(FTRACE_UPDATE_CALLS);
+ if (!ret)
+ ftrace_ops_update_code(ops);
mutex_unlock(&ftrace_lock);
@@ -3655,9 +3713,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
mutex_lock(&ftrace_lock);
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
- if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED)
- && ftrace_enabled)
- ftrace_run_update_code(FTRACE_UPDATE_CALLS);
+ if (!ret)
+ ftrace_ops_update_code(iter->ops);
mutex_unlock(&ftrace_lock);
}