git: f5fabf3dcfb6 - stable/14 - socket: Simplify synchronization in soreceive_stream()

The branch stable/14 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=f5fabf3dcfb67434d13890b9143a361478e731e2

commit f5fabf3dcfb67434d13890b9143a361478e731e2
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-07-09 14:33:53 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-07-23 13:01:53 +0000

    socket: Simplify synchronization in soreceive_stream()
    
    Now that the socket recv I/O lock is required in order to enable
    receive-side KTLS, we can move a check from out of the socket buffer
    lock, which in turn will simplify some further refactoring.
    
    Add a __predict_false annotation while here since we already perform a
    lockless check before acquiring any locks.
    
    Reviewed by:    gallatin, jhb
    MFC after:      2 weeks
    Sponsored by:   Klara, Inc.
    Sponsored by:   Stormshield
    Differential Revision:  https://reviews.freebsd.org/D45922
    
    (cherry picked from commit 30f30ccae71ce6b3bbe7b2719a3d588cb46f97ba)
---
 sys/kern/uipc_socket.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 32a6ff14bb43..479184a87a5e 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -2560,17 +2560,15 @@ soreceive_stream(struct socket *so, struct sockaddr **psa, struct uio *uio,
 	error = SOCK_IO_RECV_LOCK(so, SBLOCKWAIT(flags));
 	if (error)
 		return (error);
-	SOCKBUF_LOCK(sb);
-
 #ifdef KERN_TLS
-	if (sb->sb_tls_info != NULL) {
-		SOCKBUF_UNLOCK(sb);
+	if (__predict_false(sb->sb_tls_info != NULL)) {
 		SOCK_IO_RECV_UNLOCK(so);
 		return (soreceive_generic(so, psa, uio, mp0, controlp,
 		    flagsp));
 	}
 #endif
 
+	SOCKBUF_LOCK(sb);
 	/* Easy one, no space to copyout anything. */
 	if (uio->uio_resid == 0) {
 		error = EINVAL;