From: Willy Tarreau <w@1wt.eu>
Date: Thu, 4 Oct 2012 18:38:49 +0000 (+0200)
Subject: MEDIUM: raw_sock: improve connection error reporting
X-Git-Tag: v1.5-dev13~222
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6f5d141149e632f3bdcd09f4ba80dd9a09d1f22c;p=thirdparty%2Fhaproxy.git

MEDIUM: raw_sock: improve connection error reporting

When a connection setup is pending and we receive an error without a
POLL_IN flag, we're certain there will be nothing to read from it and
we can safely report an error without attempting a recv() call. This
will be significantly better for health checks which will avoid a useless
recv() on all failed checks.
---

diff --git a/src/raw_sock.c b/src/raw_sock.c
index c417d5a7d3..1330fadd70 100644
--- a/src/raw_sock.c
+++ b/src/raw_sock.c
@@ -70,8 +70,17 @@ int raw_sock_to_pipe(struct connection *conn, struct pipe *pipe, unsigned int co
 	 * Since older splice() implementations were buggy and returned
 	 * EAGAIN on end of read, let's bypass the call to splice() now.
 	 */
-	if ((fdtab[conn->t.sock.fd].ev & (FD_POLL_IN|FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
-		goto out_read0;
+	if (unlikely(!(fdtab[conn->t.sock.fd].ev & FD_POLL_IN))) {
+		/* stop here if we reached the end of data */
+		if ((fdtab[conn->t.sock.fd].ev & (FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
+			goto out_read0;
+
+		/* report error on POLL_ERR before connection establishment */
+		if ((fdtab[conn->t.sock.fd].ev & FD_POLL_ERR) && (conn->flags & CO_FL_WAIT_L4_CONN)) {
+			conn->flags |= CO_FL_ERROR;
+			return retval;
+		}
+	}
 
 	while (count) {
 		if (count > MAX_SPLICE_AT_ONCE)
@@ -201,9 +210,17 @@ static int raw_sock_to_buf(struct connection *conn, struct buffer *buf, int coun
 	int ret, done = 0;
 	int try = count;
 
-	/* stop here if we reached the end of data */
-	if ((fdtab[conn->t.sock.fd].ev & (FD_POLL_IN|FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
-		goto read0;
+	if (unlikely(!(fdtab[conn->t.sock.fd].ev & FD_POLL_IN))) {
+		/* stop here if we reached the end of data */
+		if ((fdtab[conn->t.sock.fd].ev & (FD_POLL_ERR|FD_POLL_HUP)) == FD_POLL_HUP)
+			goto read0;
+
+		/* report error on POLL_ERR before connection establishment */
+		if ((fdtab[conn->t.sock.fd].ev & FD_POLL_ERR) && (conn->flags & CO_FL_WAIT_L4_CONN)) {
+			conn->flags |= CO_FL_ERROR;
+			return done;
+		}
+	}
 
 	/* compute the maximum block size we can read at once. */
 	if (buffer_empty(buf)) {