6846669 squeue_synch_{enter,exit}() are unaware of squeue switching

3 files changed, 42 insertions, 32 deletions

diff --git a/usr/src/uts/common/inet/squeue.c b/usr/src/uts/common/inet/squeue.c
index a58b445158..6d0bf70b2a 100644
--- a/usr/src/uts/common/inet/squeue.c
+++ b/usr/src/uts/common/inet/squeue.c
@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 /*
@@ -1383,8 +1382,13 @@ squeue_wakeup_conn(void *arg, mblk_t *mp, void *arg2, ip_recv_attr_t *dummy)
 }
 
 int
-squeue_synch_enter(squeue_t *sqp, conn_t *connp, mblk_t *use_mp)
+squeue_synch_enter(conn_t *connp, mblk_t *use_mp)
 {
+	squeue_t *sqp;
+
+again:
+	sqp = connp->conn_sqp;
+
 	mutex_enter(&sqp->sq_lock);
 	if (sqp->sq_first == NULL && !(sqp->sq_state & SQS_PROC)) {
 		/*
@@ -1400,6 +1404,19 @@ squeue_synch_enter(squeue_t *sqp, conn_t *connp, mblk_t *use_mp)
 		sqp->sq_run = curthread;
 		mutex_exit(&sqp->sq_lock);
 
+		/*
+		 * Handle squeue switching. The conn's squeue can only change
+		 * while there is a thread in the squeue, which is why we do
+		 * the check after entering the squeue. If it has changed, exit
+		 * this squeue and redo everything with the new sqeueue.
+		 */
+		if (sqp != connp->conn_sqp) {
+			mutex_enter(&sqp->sq_lock);
+			sqp->sq_state &= ~SQS_PROC;
+			sqp->sq_run = NULL;
+			mutex_exit(&sqp->sq_lock);
+			goto again;
+		}
 #if SQUEUE_DEBUG
 		sqp->sq_curmp = NULL;
 		sqp->sq_curproc = NULL;
@@ -1443,8 +1460,10 @@ squeue_synch_enter(squeue_t *sqp, conn_t *connp, mblk_t *use_mp)
 }
 
 void
-squeue_synch_exit(squeue_t *sqp, conn_t *connp)
+squeue_synch_exit(conn_t *connp)
 {
+	squeue_t *sqp = connp->conn_sqp;
+
 	mutex_enter(&sqp->sq_lock);
 	if (sqp->sq_run == curthread) {
 		ASSERT(sqp->sq_state & SQS_PROC);
diff --git a/usr/src/uts/common/inet/tcp/tcp_socket.c b/usr/src/uts/common/inet/tcp/tcp_socket.c
index 7f96a851ef..4b50c65cc6 100644
--- a/usr/src/uts/common/inet/tcp/tcp_socket.c
+++ b/usr/src/uts/common/inet/tcp/tcp_socket.c
@@ -20,8 +20,7 @@
  */
 
 /*
- * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 /* This file contains all TCP kernel socket related functions. */
@@ -156,15 +155,12 @@ tcp_bind(sock_lower_handle_t proto_handle, struct sockaddr *sa,
 {
 	int 		error;
 	conn_t		*connp = (conn_t *)proto_handle;
-	squeue_t	*sqp = connp->conn_sqp;
 
 	/* All Solaris components should pass a cred for this operation. */
 	ASSERT(cr != NULL);
-
-	ASSERT(sqp != NULL);
 	ASSERT(connp->conn_upper_handle != NULL);
 
-	error = squeue_synch_enter(sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error != 0) {
 		/* failed to enter */
 		return (ENOSR);
@@ -180,7 +176,7 @@ tcp_bind(sock_lower_handle_t proto_handle, struct sockaddr *sa,
 		error = tcp_do_bind(connp, sa, len, cr, B_TRUE);
 	}
 
-	squeue_synch_exit(sqp, connp);
+	squeue_synch_exit(connp);
 
 	if (error < 0) {
 		if (error == -TOUTSTATE)
@@ -201,14 +197,13 @@ tcp_listen(sock_lower_handle_t proto_handle, int backlog, cred_t *cr)
 {
 	conn_t	*connp = (conn_t *)proto_handle;
 	int 	error;
-	squeue_t *sqp = connp->conn_sqp;
 
 	ASSERT(connp->conn_upper_handle != NULL);
 
 	/* All Solaris components should pass a cred for this operation. */
 	ASSERT(cr != NULL);
 
-	error = squeue_synch_enter(sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error != 0) {
 		/* failed to enter */
 		return (ENOBUFS);
@@ -224,7 +219,7 @@ tcp_listen(sock_lower_handle_t proto_handle, int backlog, cred_t *cr)
 		else
 			error = proto_tlitosyserr(-error);
 	}
-	squeue_synch_exit(sqp, connp);
+	squeue_synch_exit(connp);
 	return (error);
 }
 
@@ -233,7 +228,6 @@ tcp_connect(sock_lower_handle_t proto_handle, const struct sockaddr *sa,
     socklen_t len, sock_connid_t *id, cred_t *cr)
 {
 	conn_t		*connp = (conn_t *)proto_handle;
-	squeue_t	*sqp = connp->conn_sqp;
 	int		error;
 
 	ASSERT(connp->conn_upper_handle != NULL);
@@ -246,7 +240,7 @@ tcp_connect(sock_lower_handle_t proto_handle, const struct sockaddr *sa,
 		return (error);
 	}
 
-	error = squeue_synch_enter(sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error != 0) {
 		/* failed to enter */
 		return (ENOSR);
@@ -289,7 +283,7 @@ tcp_connect(sock_lower_handle_t proto_handle, const struct sockaddr *sa,
 		    connp->conn_upper_handle, &sopp);
 	}
 done:
-	squeue_synch_exit(sqp, connp);
+	squeue_synch_exit(connp);
 
 	return ((error == 0) ? EINPROGRESS : error);
 }
@@ -333,7 +327,6 @@ tcp_getsockopt(sock_lower_handle_t proto_handle, int level, int option_name,
     void *optvalp, socklen_t *optlen, cred_t *cr)
 {
 	conn_t		*connp = (conn_t *)proto_handle;
-	squeue_t	*sqp = connp->conn_sqp;
 	int		error;
 	t_uscalar_t	max_optbuf_len;
 	void		*optvalp_buf;
@@ -354,14 +347,14 @@ tcp_getsockopt(sock_lower_handle_t proto_handle, int level, int option_name,
 
 	optvalp_buf = kmem_alloc(max_optbuf_len, KM_SLEEP);
 
-	error = squeue_synch_enter(sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error == ENOMEM) {
 		kmem_free(optvalp_buf, max_optbuf_len);
 		return (ENOMEM);
 	}
 
 	len = tcp_opt_get(connp, level, option_name, optvalp_buf);
-	squeue_synch_exit(sqp, connp);
+	squeue_synch_exit(connp);
 
 	if (len == -1) {
 		kmem_free(optvalp_buf, max_optbuf_len);
@@ -385,7 +378,6 @@ tcp_setsockopt(sock_lower_handle_t proto_handle, int level, int option_name,
     const void *optvalp, socklen_t optlen, cred_t *cr)
 {
 	conn_t		*connp = (conn_t *)proto_handle;
-	squeue_t	*sqp = connp->conn_sqp;
 	int		error;
 
 	ASSERT(connp->conn_upper_handle != NULL);
@@ -409,7 +401,7 @@ tcp_setsockopt(sock_lower_handle_t proto_handle, int level, int option_name,
 		}
 	}
 
-	error = squeue_synch_enter(sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error == ENOMEM) {
 		return (ENOMEM);
 	}
@@ -423,14 +415,14 @@ tcp_setsockopt(sock_lower_handle_t proto_handle, int level, int option_name,
 		if (error < 0) {
 			error = proto_tlitosyserr(-error);
 		}
-		squeue_synch_exit(sqp, connp);
+		squeue_synch_exit(connp);
 		return (error);
 	}
 
 	error = tcp_opt_set(connp, SETFN_OPTCOM_NEGOTIATE, level, option_name,
 	    optlen, (uchar_t *)optvalp, (uint_t *)&optlen, (uchar_t *)optvalp,
 	    NULL, cr);
-	squeue_synch_exit(sqp, connp);
+	squeue_synch_exit(connp);
 
 	ASSERT(error >= 0);
 
@@ -581,7 +573,7 @@ tcp_clr_flowctrl(sock_lower_handle_t proto_handle)
 	tcp->tcp_rsrv_mp = NULL;
 	mutex_exit(&tcp->tcp_rsrv_mp_lock);
 
-	error = squeue_synch_enter(connp->conn_sqp, connp, mp);
+	error = squeue_synch_enter(connp, mp);
 	ASSERT(error == 0);
 
 	mutex_enter(&tcp->tcp_rsrv_mp_lock);
@@ -606,7 +598,7 @@ tcp_clr_flowctrl(sock_lower_handle_t proto_handle)
 		}
 	}
 
-	squeue_synch_exit(connp->conn_sqp, connp);
+	squeue_synch_exit(connp);
 }
 
 /* ARGSUSED */
@@ -771,7 +763,7 @@ tcp_fallback(sock_lower_handle_t proto_handle, queue_t *q,
 	/*
 	 * Enter the squeue so that no new packets can come in
 	 */
-	error = squeue_synch_enter(connp->conn_sqp, connp, NULL);
+	error = squeue_synch_enter(connp, NULL);
 	if (error != 0) {
 		/* failed to enter, free all the pre-allocated messages. */
 		freeb(stropt_mp);
@@ -814,7 +806,7 @@ tcp_fallback(sock_lower_handle_t proto_handle, queue_t *q,
 	 * There should be atleast two ref's (IP + TCP)
 	 */
 	ASSERT(connp->conn_ref >= 2);
-	squeue_synch_exit(connp->conn_sqp, connp);
+	squeue_synch_exit(connp);
 
 	return (0);
 }
diff --git a/usr/src/uts/common/sys/squeue.h b/usr/src/uts/common/sys/squeue.h
index de0f18bd4d..f1bd429815 100644
--- a/usr/src/uts/common/sys/squeue.h
+++ b/usr/src/uts/common/sys/squeue.h
@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 #ifndef	_SYS_SQUEUE_H
@@ -85,8 +84,8 @@ extern void squeue_enter(squeue_t *, mblk_t *, mblk_t *,
 extern uintptr_t *squeue_getprivate(squeue_t *, sqprivate_t);
 
 struct conn_s;
-extern int squeue_synch_enter(squeue_t *, struct conn_s *, mblk_t *);
-extern void squeue_synch_exit(squeue_t *, struct conn_s *);
+extern int squeue_synch_enter(struct conn_s *, mblk_t *);
+extern void squeue_synch_exit(struct conn_s *);
 
 #ifdef	__cplusplus
 }