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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c98
1 files changed, 69 insertions, 29 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b3fde6d7b7f..8a5c017bb50 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -486,7 +486,6 @@ struct ftrace_profile_stat {
#define PROFILES_PER_PAGE \
(PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile))
-static int ftrace_profile_bits __read_mostly;
static int ftrace_profile_enabled __read_mostly;
/* ftrace_profile_lock - synchronize the enable and disable of the profiler */
@@ -494,7 +493,8 @@ static DEFINE_MUTEX(ftrace_profile_lock);
static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats);
-#define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */
+#define FTRACE_PROFILE_HASH_BITS 10
+#define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS)
static void *
function_stat_next(void *v, int idx)
@@ -676,7 +676,7 @@ int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE);
- for (i = 0; i < pages; i++) {
+ for (i = 1; i < pages; i++) {
pg->next = (void *)get_zeroed_page(GFP_KERNEL);
if (!pg->next)
goto out_free;
@@ -724,13 +724,6 @@ static int ftrace_profile_init_cpu(int cpu)
if (!stat->hash)
return -ENOMEM;
- if (!ftrace_profile_bits) {
- size--;
-
- for (; size; size >>= 1)
- ftrace_profile_bits++;
- }
-
/* Preallocate the function profiling pages */
if (ftrace_profile_pages_init(stat) < 0) {
kfree(stat->hash);
@@ -763,7 +756,7 @@ ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip)
struct hlist_head *hhd;
unsigned long key;
- key = hash_long(ip, ftrace_profile_bits);
+ key = hash_long(ip, FTRACE_PROFILE_HASH_BITS);
hhd = &stat->hash[key];
if (hlist_empty(hhd))
@@ -782,7 +775,7 @@ static void ftrace_add_profile(struct ftrace_profile_stat *stat,
{
unsigned long key;
- key = hash_long(rec->ip, ftrace_profile_bits);
+ key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS);
hlist_add_head_rcu(&rec->node, &stat->hash[key]);
}
@@ -1079,7 +1072,7 @@ struct ftrace_func_probe {
unsigned long flags;
unsigned long ip;
void *data;
- struct rcu_head rcu;
+ struct list_head free_list;
};
struct ftrace_func_entry {
@@ -1329,7 +1322,6 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
struct hlist_head *hhd;
struct ftrace_hash *old_hash;
struct ftrace_hash *new_hash;
- unsigned long key;
int size = src->count;
int bits = 0;
int ret;
@@ -1372,10 +1364,6 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
for (i = 0; i < size; i++) {
hhd = &src->buckets[i];
hlist_for_each_entry_safe(entry, tn, hhd, hlist) {
- if (bits > 0)
- key = hash_long(entry->ip, bits);
- else
- key = 0;
remove_hash_entry(src, entry);
__add_hash_entry(new_hash, entry);
}
@@ -2973,28 +2961,27 @@ static void __disable_ftrace_function_probe(void)
}
-static void ftrace_free_entry_rcu(struct rcu_head *rhp)
+static void ftrace_free_entry(struct ftrace_func_probe *entry)
{
- struct ftrace_func_probe *entry =
- container_of(rhp, struct ftrace_func_probe, rcu);
-
if (entry->ops->free)
- entry->ops->free(&entry->data);
+ entry->ops->free(entry->ops, entry->ip, &entry->data);
kfree(entry);
}
-
int
register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data)
{
struct ftrace_func_probe *entry;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct ftrace_hash *hash;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
int type, len, not;
unsigned long key;
int count = 0;
char *search;
+ int ret;
type = filter_parse_regex(glob, strlen(glob), &search, &not);
len = strlen(search);
@@ -3005,8 +2992,16 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
mutex_lock(&ftrace_lock);
- if (unlikely(ftrace_disabled))
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ if (!hash) {
+ count = -ENOMEM;
goto out_unlock;
+ }
+
+ if (unlikely(ftrace_disabled)) {
+ count = -ENODEV;
+ goto out_unlock;
+ }
do_for_each_ftrace_rec(pg, rec) {
@@ -3030,14 +3025,21 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
* for each function we find. We call the callback
* to give the caller an opportunity to do so.
*/
- if (ops->callback) {
- if (ops->callback(rec->ip, &entry->data) < 0) {
+ if (ops->init) {
+ if (ops->init(ops, rec->ip, &entry->data) < 0) {
/* caller does not like this func */
kfree(entry);
continue;
}
}
+ ret = enter_record(hash, rec, 0);
+ if (ret < 0) {
+ kfree(entry);
+ count = ret;
+ goto out_unlock;
+ }
+
entry->ops = ops;
entry->ip = rec->ip;
@@ -3045,10 +3047,16 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
} while_for_each_ftrace_rec();
+
+ ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ if (ret < 0)
+ count = ret;
+
__enable_ftrace_function_probe();
out_unlock:
mutex_unlock(&ftrace_lock);
+ free_ftrace_hash(hash);
return count;
}
@@ -3062,7 +3070,12 @@ static void
__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data, int flags)
{
+ struct ftrace_func_entry *rec_entry;
struct ftrace_func_probe *entry;
+ struct ftrace_func_probe *p;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct list_head free_list;
+ struct ftrace_hash *hash;
struct hlist_node *tmp;
char str[KSYM_SYMBOL_LEN];
int type = MATCH_FULL;
@@ -3083,6 +3096,14 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
}
mutex_lock(&ftrace_lock);
+
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ if (!hash)
+ /* Hmm, should report this somehow */
+ goto out_unlock;
+
+ INIT_LIST_HEAD(&free_list);
+
for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
struct hlist_head *hhd = &ftrace_func_hash[i];
@@ -3103,12 +3124,30 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
continue;
}
+ rec_entry = ftrace_lookup_ip(hash, entry->ip);
+ /* It is possible more than one entry had this ip */
+ if (rec_entry)
+ free_hash_entry(hash, rec_entry);
+
hlist_del_rcu(&entry->node);
- call_rcu_sched(&entry->rcu, ftrace_free_entry_rcu);
+ list_add(&entry->free_list, &free_list);
}
}
__disable_ftrace_function_probe();
+ /*
+ * Remove after the disable is called. Otherwise, if the last
+ * probe is removed, a null hash means *all enabled*.
+ */
+ ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ synchronize_sched();
+ list_for_each_entry_safe(entry, p, &free_list, free_list) {
+ list_del(&entry->free_list);
+ ftrace_free_entry(entry);
+ }
+
+ out_unlock:
mutex_unlock(&ftrace_lock);
+ free_ftrace_hash(hash);
}
void
@@ -3736,7 +3775,8 @@ out:
if (fail)
return -EINVAL;
- ftrace_graph_filter_enabled = 1;
+ ftrace_graph_filter_enabled = !!(*idx);
+
return 0;
}
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 15:11:16 +0000