[RFC PATCH 25/27] lift rcu_read_lock() into reverse_path_check()

From: Al Viro
Date: Sat Oct 03 2020 - 22:40:16 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/eventpoll.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 78b8769b72dc..8a7ad752befd 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1257,7 +1257,6 @@ static int reverse_path_check_proc(struct file *file, int depth)
return -1;

/* CTL_DEL can remove links here, but that can't increase our count */
- rcu_read_lock();
hlist_for_each_entry_rcu(epi, &file->f_ep_links, fllink) {
struct file *recepient = epi->ep->file;
if (WARN_ON(!is_file_epoll(recepient)))
@@ -1269,7 +1268,6 @@ static int reverse_path_check_proc(struct file *file, int depth)
if (error != 0)
break;
}
- rcu_read_unlock();
return error;
}

@@ -1291,7 +1289,9 @@ static int reverse_path_check(void)
/* let's call this for all tfiles */
list_for_each_entry(current_file, &tfile_check_list, f_tfile_llink) {
path_count_init();
+ rcu_read_lock();
error = reverse_path_check_proc(current_file, 0);
+ rcu_read_unlock();
if (error)
break;
}
--
2.11.0