[RFC PATCH 05/27] untangling ep_call_nested(): take pushing cookie into a helper

Al Viro
2020-10-04T02:41:04Z

fs/eventpoll.c | 26 +++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 43aecae0935c..bd2cc78c47c8 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -424,6 +424,21 @@ static inline void ep_set_busy_poll_napi_id(struct epitem *epi)

#endif /* CONFIG_NET_RX_BUSY_POLL */

+static bool ep_push_nested(void *cookie)
+{
+ int i;
+
+ if (nesting > EP_MAX_NESTS) /* too deep nesting */
+ return false;
+
+ for (i = 0; i < nesting; i++) {
+ if (cookies[i] == cookie) /* loop detected */
+ return false;
+ }
+ cookies[nesting++] = cookie;
+ return true;
+}
+
/**
* ep_call_nested - Perform a bound (possibly) nested call, by checking
* that the recursion limit is not exceeded, and that
@@ -440,17 +455,10 @@ static inline void ep_set_busy_poll_napi_id(struct epitem *epi)
static int ep_call_nested(int (*nproc)(void *, void *, int), void *priv,
void *cookie)
{
- int error, i;
+ int error;

- if (nesting > EP_MAX_NESTS) /* too deep nesting */
+ if (!ep_push_nested(cookie))
return -1;
-
- for (i = 0; i < nesting; i++) {
- if (cookies[i] == cookie) /* loop detected */
- return -1;
- }
- cookies[nesting++] = cookie;
-
/* Call the nested function */
error = (*nproc)(priv, cookie, nesting - 1);
nesting--;
--
2.11.0