diff options
Diffstat (limited to 'kernel/trace/ftrace.c')
| -rw-r--r-- | kernel/trace/ftrace.c | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 86dbbfb353db..a5824408bed9 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5683,6 +5683,7 @@ struct ftrace_mod_func { }; struct ftrace_mod_map { + struct rcu_head rcu; struct list_head list; struct module *mod; unsigned long start_addr; @@ -5694,6 +5695,8 @@ struct ftrace_mod_map { #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) +static LIST_HEAD(ftrace_mod_maps); + static int referenced_filters(struct dyn_ftrace *rec) { struct ftrace_ops *ops; @@ -5747,8 +5750,26 @@ static void clear_mod_from_hashes(struct ftrace_page *pg) mutex_unlock(&trace_types_lock); } +static void ftrace_free_mod_map(struct rcu_head *rcu) +{ + struct ftrace_mod_map *mod_map = container_of(rcu, struct ftrace_mod_map, rcu); + struct ftrace_mod_func *mod_func; + struct ftrace_mod_func *n; + + /* All the contents of mod_map are now not visible to readers */ + list_for_each_entry_safe(mod_func, n, &mod_map->funcs, list) { + kfree(mod_func->name); + list_del(&mod_func->list); + kfree(mod_func); + } + + kfree(mod_map); +} + void ftrace_release_mod(struct module *mod) { + struct ftrace_mod_map *mod_map; + struct ftrace_mod_map *n; struct dyn_ftrace *rec; struct ftrace_page **last_pg; struct ftrace_page *tmp_page = NULL; @@ -5760,6 +5781,14 @@ void ftrace_release_mod(struct module *mod) if (ftrace_disabled) goto out_unlock; + list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) { + if (mod_map->mod == mod) { + list_del_rcu(&mod_map->list); + call_rcu_sched(&mod_map->rcu, ftrace_free_mod_map); + break; + } + } + /* * Each module has its own ftrace_pages, remove * them from the list. @@ -5914,8 +5943,6 @@ static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, list_add_rcu(&mod_func->list, &mod_map->funcs); } -static LIST_HEAD(ftrace_mod_maps); - static struct ftrace_mod_map * allocate_ftrace_mod_map(struct module *mod, unsigned long start, unsigned long end) @@ -5974,6 +6001,7 @@ ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, struct ftrace_mod_map *mod_map; const char *ret = NULL; + /* mod_map is freed via call_rcu_sched() */ preempt_disable(); list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym); |