From: Willy Tarreau <w@1wt.eu>
Date: Thu, 20 Feb 2020 10:23:43 +0000 (+0100)
Subject: CLEANUP: epoll: place the struct epoll_event in the stack
X-Git-Tag: v2.2-dev3~45
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=902871dd07db6e2e7a7139be5a571b4078fe49c3;p=thirdparty%2Fhaproxy.git

CLEANUP: epoll: place the struct epoll_event in the stack

Historically we used to have a global epoll_event for various
manipulations involving epoll_ctl() and when threads were added,
this was turned to a thread_local, which is needlessly expensive
since it's just a temporary variable. Let's move it to a local
variable wherever it's called instead.
---

diff --git a/src/ev_epoll.c b/src/ev_epoll.c
index 1f8ef2b889..bbba0ec4ed 100644
--- a/src/ev_epoll.c
+++ b/src/ev_epoll.c
@@ -34,11 +34,6 @@
 static THREAD_LOCAL struct epoll_event *epoll_events = NULL;
 static int epoll_fd[MAX_THREADS]; // per-thread epoll_fd
 
-/* This structure may be used for any purpose. Warning! do not use it in
- * recursive functions !
- */
-static THREAD_LOCAL struct epoll_event ev;
-
 #ifndef EPOLLRDHUP
 /* EPOLLRDHUP was defined late in libc, and it appeared in kernel 2.6.17 */
 #define EPOLLRDHUP 0x2000
@@ -54,6 +49,7 @@ REGPRM1 static void __fd_clo(int fd)
 {
 	if (unlikely(fdtab[fd].cloned)) {
 		unsigned long m = polled_mask[fd].poll_recv | polled_mask[fd].poll_send;
+		struct epoll_event ev;
 		int i;
 
 		for (i = global.nbthread - 1; i >= 0; i--)
@@ -65,6 +61,7 @@ REGPRM1 static void __fd_clo(int fd)
 static void _update_fd(int fd)
 {
 	int en, opcode;
+	struct epoll_event ev;
 
 	en = fdtab[fd].state;
 
@@ -209,8 +206,10 @@ REGPRM3 static void _do_poll(struct poller *p, int exp, int wake)
 	/* process polled events */
 
 	for (count = 0; count < status; count++) {
-		unsigned int n;
-		unsigned int e = epoll_events[count].events;
+		struct epoll_event ev;
+		unsigned int n, e;
+
+		e = epoll_events[count].events;
 		fd = epoll_events[count].data.fd;
 
 		if (!fdtab[fd].owner) {