From: Olivier Houchard <ohouchard@haproxy.com>
Date: Thu, 25 Jul 2019 14:00:18 +0000 (+0000)
Subject: MEDIUM: pollers: Remember the state for read and write for each threads.
X-Git-Tag: v2.1-dev2~255
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=53055055c517d018a36677cbae0a0ad464700fd4;p=thirdparty%2Fhaproxy.git

MEDIUM: pollers: Remember the state for read and write for each threads.

In the poller code, instead of just remembering if we're currently polling
a fd or not, remember if we're polling it for writing and/or for reading, that
way, we can avoid to modify the polling if it's already polled as needed.
---

diff --git a/include/proto/fd.h b/include/proto/fd.h
index 673eaae0f5..4fbb9dc1af 100644
--- a/include/proto/fd.h
+++ b/include/proto/fd.h
@@ -37,7 +37,11 @@
 
 extern volatile struct fdlist update_list;
 
-extern unsigned long *polled_mask;
+
+extern struct polled_mask {
+	unsigned long poll_recv;
+	unsigned long poll_send;
+} *polled_mask;
 
 extern THREAD_LOCAL int *fd_updt;  // FD updates list
 extern THREAD_LOCAL int fd_nbupdt; // number of updates in the list
diff --git a/src/ev_epoll.c b/src/ev_epoll.c
index bd2d616cd1..dd3a561b23 100644
--- a/src/ev_epoll.c
+++ b/src/ev_epoll.c
@@ -53,7 +53,7 @@ static THREAD_LOCAL struct epoll_event ev;
 REGPRM1 static void __fd_clo(int fd)
 {
 	if (unlikely(fdtab[fd].cloned)) {
-		unsigned long m = polled_mask[fd];
+		unsigned long m = polled_mask[fd].poll_recv | polled_mask[fd].poll_send;
 		int i;
 
 		for (i = global.nbthread - 1; i >= 0; i--)
@@ -68,13 +68,35 @@ static void _update_fd(int fd)
 
 	en = fdtab[fd].state;
 
-	if (polled_mask[fd] & tid_bit) {
+	if ((polled_mask[fd].poll_send | polled_mask[fd].poll_recv) & tid_bit) {
 		if (!(fdtab[fd].thread_mask & tid_bit) || !(en & FD_EV_POLLED_RW)) {
 			/* fd removed from poll list */
 			opcode = EPOLL_CTL_DEL;
-			_HA_ATOMIC_AND(&polled_mask[fd], ~tid_bit);
+			if (polled_mask[fd].poll_recv & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+			if (polled_mask[fd].poll_send & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
 		}
 		else {
+			if (((en & FD_EV_POLLED_R) != 0) ==
+			    ((polled_mask[fd].poll_recv & tid_bit) != 0) &&
+			    ((en & FD_EV_POLLED_W) != 0) ==
+			    ((polled_mask[fd].poll_send & tid_bit) != 0))
+				return;
+			if (en & FD_EV_POLLED_R) {
+				if (!(polled_mask[fd].poll_recv & tid_bit))
+					_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+			} else {
+				if (polled_mask[fd].poll_recv & tid_bit)
+					_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+			}
+			if (en & FD_EV_POLLED_W) {
+				if (!(polled_mask[fd].poll_send & tid_bit))
+					_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
+			} else {
+				if (polled_mask[fd].poll_send & tid_bit)
+					_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
+			}
 			/* fd status changed */
 			opcode = EPOLL_CTL_MOD;
 		}
@@ -82,7 +104,10 @@ static void _update_fd(int fd)
 	else if ((fdtab[fd].thread_mask & tid_bit) && (en & FD_EV_POLLED_RW)) {
 		/* new fd in the poll list */
 		opcode = EPOLL_CTL_ADD;
-		_HA_ATOMIC_OR(&polled_mask[fd], tid_bit);
+		if (en & FD_EV_POLLED_R)
+			_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+		if (en & FD_EV_POLLED_W)
+			_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
 	}
 	else {
 		return;
@@ -188,7 +213,8 @@ REGPRM3 static void _do_poll(struct poller *p, int exp, int wake)
 			/* FD has been migrated */
 			activity[tid].poll_skip++;
 			epoll_ctl(epoll_fd[tid], EPOLL_CTL_DEL, fd, &ev);
-			_HA_ATOMIC_AND(&polled_mask[fd], ~tid_bit);
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
 			continue;
 		}
 
diff --git a/src/ev_evports.c b/src/ev_evports.c
index 7842bf242b..d9d1637d41 100644
--- a/src/ev_evports.c
+++ b/src/ev_evports.c
@@ -74,18 +74,36 @@ static void _update_fd(int fd)
 	en = fdtab[fd].state;
 
 	if (!(fdtab[fd].thread_mask & tid_bit) || !(en & FD_EV_POLLED_RW)) {
-		if (!(polled_mask[fd] & tid_bit)) {
+		if (!(polled_mask[fd].poll_recv & tid_bit) &&
+		    !(polled_mask[fd].poll_send & tid_bit)) {
 			/* fd was not watched, it's still not */
 			return;
 		}
 		/* fd totally removed from poll list */
 		events = 0;
-		_HA_ATOMIC_AND(&polled_mask[fd], ~tid_bit);
+		if (polled_mask[fd].poll_recv & tid_bit)
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		if (polled_mask[fd].poll_send & tid_bit)
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
 	}
 	else {
 		/* OK fd has to be monitored, it was either added or changed */
 		events = evports_state_to_events(en);
-		_HA_ATOMIC_OR(&polled_mask[fd], tid_bit);
+		if (en & FD_EV_POLLED_R) {
+			if (!(polled_mask[fd].poll_recv & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+		} else {
+			if (polled_mask[fd].poll_recv & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		}
+		if (en & FD_EV_POLLED_W) {
+			if (!(polled_mask[fd].poll_send & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
+		} else {
+			if (polled_mask[fd].poll_send & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
+		}
+
 	}
 	evports_resync_fd(fd, events);
 }
diff --git a/src/ev_kqueue.c b/src/ev_kqueue.c
index 692437731b..d634b67280 100644
--- a/src/ev_kqueue.c
+++ b/src/ev_kqueue.c
@@ -44,29 +44,44 @@ static int _update_fd(int fd, int start)
 	en = fdtab[fd].state;
 
 	if (!(fdtab[fd].thread_mask & tid_bit) || !(en & FD_EV_POLLED_RW)) {
-		if (!(polled_mask[fd] & tid_bit)) {
+		if (!(polled_mask[fd].poll_recv & tid_bit) &&
+		    !(polled_mask[fd].poll_send & tid_bit)) {
 			/* fd was not watched, it's still not */
 			return changes;
 		}
 		/* fd totally removed from poll list */
 		EV_SET(&kev[changes++], fd, EVFILT_READ, EV_DELETE, 0, 0, NULL);
 		EV_SET(&kev[changes++], fd, EVFILT_WRITE, EV_DELETE, 0, 0, NULL);
-		_HA_ATOMIC_AND(&polled_mask[fd], ~tid_bit);
+		if (polled_mask[fd].poll_recv & tid_bit)
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		if (polled_mask[fd].poll_send & tid_bit)
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
 	}
 	else {
 		/* OK fd has to be monitored, it was either added or changed */
 
-		if (en & FD_EV_POLLED_R)
-			EV_SET(&kev[changes++], fd, EVFILT_READ, EV_ADD, 0, 0, NULL);
-		else if (polled_mask[fd] & tid_bit)
+		if (en & FD_EV_POLLED_R) {
+			if (!(polled_mask[fd].poll_recv & tid_bit)) {
+				EV_SET(&kev[changes++], fd, EVFILT_READ, EV_ADD, 0, 0, NULL);
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+			}
+		}
+		else if (polled_mask[fd].poll_recv & tid_bit) {
 			EV_SET(&kev[changes++], fd, EVFILT_READ, EV_DELETE, 0, 0, NULL);
+			HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		}
 
-		if (en & FD_EV_POLLED_W)
-			EV_SET(&kev[changes++], fd, EVFILT_WRITE, EV_ADD, 0, 0, NULL);
-		else if (polled_mask[fd] & tid_bit)
+		if (en & FD_EV_POLLED_W) {
+			if (!(polled_mask[fd].poll_send & tid_bit)) {
+				EV_SET(&kev[changes++], fd, EVFILT_WRITE, EV_ADD, 0, 0, NULL);
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
+			}
+		}
+		else if (polled_mask[fd].poll_send & tid_bit) {
 			EV_SET(&kev[changes++], fd, EVFILT_WRITE, EV_DELETE, 0, 0, NULL);
+			_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
+		}
 
-		_HA_ATOMIC_OR(&polled_mask[fd], tid_bit);
 	}
 	return changes;
 }
diff --git a/src/ev_poll.c b/src/ev_poll.c
index b349c555f6..d4a1351a2b 100644
--- a/src/ev_poll.c
+++ b/src/ev_poll.c
@@ -58,28 +58,38 @@ static void _update_fd(int fd, int *max_add_fd)
 	 * takes it for every other one.
 	 */
 	if (!(en & FD_EV_POLLED_RW)) {
-		if (!polled_mask[fd]) {
+		if (!(polled_mask[fd].poll_recv | polled_mask[fd].poll_send)) {
 			/* fd was not watched, it's still not */
 			return;
 		}
 		/* fd totally removed from poll list */
 		hap_fd_clr(fd, fd_evts[DIR_RD]);
 		hap_fd_clr(fd, fd_evts[DIR_WR]);
-		_HA_ATOMIC_AND(&polled_mask[fd], 0);
+		_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, 0);
+		_HA_ATOMIC_AND(&polled_mask[fd].poll_send, 0);
 	}
 	else {
 		/* OK fd has to be monitored, it was either added or changed */
-		if (!(en & FD_EV_POLLED_R))
+		if (!(en & FD_EV_POLLED_R)) {
 			hap_fd_clr(fd, fd_evts[DIR_RD]);
-		else
+			if (polled_mask[fd].poll_recv & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		} else {
 			hap_fd_set(fd, fd_evts[DIR_RD]);
+			if (!(polled_mask[fd].poll_recv & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+		}
 
-		if (!(en & FD_EV_POLLED_W))
+		if (!(en & FD_EV_POLLED_W)) {
 			hap_fd_clr(fd, fd_evts[DIR_WR]);
-		else
+			if (polled_mask[fd].poll_send & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
+		}else {
 			hap_fd_set(fd, fd_evts[DIR_WR]);
+			if (!(polled_mask[fd].poll_send & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
+		}
 
-		_HA_ATOMIC_OR(&polled_mask[fd], tid_bit);
 		if (fd > *max_add_fd)
 			*max_add_fd = fd;
 	}
diff --git a/src/ev_select.c b/src/ev_select.c
index be88bc2bf4..f2a2acfa05 100644
--- a/src/ev_select.c
+++ b/src/ev_select.c
@@ -49,28 +49,38 @@ static void _update_fd(int fd, int *max_add_fd)
 	 * takes it for every other one.
 	 */
 	if (!(en & FD_EV_POLLED_RW)) {
-		if (!polled_mask[fd]) {
+		if (!(polled_mask[fd].poll_recv | polled_mask[fd].poll_send)) {
 			/* fd was not watched, it's still not */
 			return;
 		}
 		/* fd totally removed from poll list */
 		hap_fd_clr(fd, fd_evts[DIR_RD]);
 		hap_fd_clr(fd, fd_evts[DIR_WR]);
-		_HA_ATOMIC_AND(&polled_mask[fd], 0);
+		_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, 0);
+		_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, 0);
 	}
 	else {
 		/* OK fd has to be monitored, it was either added or changed */
-		if (!(en & FD_EV_POLLED_R))
+		if (!(en & FD_EV_POLLED_R)) {
 			hap_fd_clr(fd, fd_evts[DIR_RD]);
-		else
+			if (polled_mask[fd].poll_recv & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_recv, ~tid_bit);
+		} else {
 			hap_fd_set(fd, fd_evts[DIR_RD]);
+			if (!(polled_mask[fd].poll_recv & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_recv, tid_bit);
+		}
 
-		if (!(en & FD_EV_POLLED_W))
+		if (!(en & FD_EV_POLLED_W)) {
 			hap_fd_clr(fd, fd_evts[DIR_WR]);
-		else
+			if (polled_mask[fd].poll_send & tid_bit)
+				_HA_ATOMIC_AND(&polled_mask[fd].poll_send, ~tid_bit);
+		} else {
 			hap_fd_set(fd, fd_evts[DIR_WR]);
+			if (!(polled_mask[fd].poll_send & tid_bit))
+				_HA_ATOMIC_OR(&polled_mask[fd].poll_send, tid_bit);
+		}
 
-		_HA_ATOMIC_OR(&polled_mask[fd], tid_bit);
 		if (fd > *max_add_fd)
 			*max_add_fd = fd;
 	}
diff --git a/src/fd.c b/src/fd.c
index 71df46e05e..a1a457802e 100644
--- a/src/fd.c
+++ b/src/fd.c
@@ -122,7 +122,7 @@
 #include <proto/port_range.h>
 
 struct fdtab *fdtab = NULL;     /* array of all the file descriptors */
-unsigned long *polled_mask = NULL; /* Array for the polled_mask of each fd */
+struct polled_mask *polled_mask = NULL; /* Array for the polled_mask of each fd */
 struct fdinfo *fdinfo = NULL;   /* less-often used infos for file descriptors */
 int totalconn;                  /* total # of terminated sessions */
 int actconn;                    /* # of active sessions */
@@ -338,7 +338,7 @@ static void fd_dodelete(int fd, int do_close)
 	fdtab[fd].owner = NULL;
 	fdtab[fd].thread_mask = 0;
 	if (do_close) {
-		polled_mask[fd] = 0;
+		polled_mask[fd].poll_recv = polled_mask[fd].poll_send = 0;
 		close(fd);
 		_HA_ATOMIC_SUB(&ha_used_fds, 1);
 	}
@@ -525,7 +525,7 @@ int init_pollers()
 	if ((fdtab = calloc(global.maxsock, sizeof(struct fdtab))) == NULL)
 		goto fail_tab;
 
-	if ((polled_mask = calloc(global.maxsock, sizeof(unsigned long))) == NULL)
+	if ((polled_mask = calloc(global.maxsock, sizeof(*polled_mask))) == NULL)
 		goto fail_polledmask;
 
 	if ((fdinfo = calloc(global.maxsock, sizeof(struct fdinfo))) == NULL)