git: c4522efca63f - stable/15 - libthr/thread/thr_join.c: deduplicate backout_join() helper

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=c4522efca63f6b72a7d7083998f8482feaab83a6

commit c4522efca63f6b72a7d7083998f8482feaab83a6
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-01-18 12:23:14 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-01-25 00:23:35 +0000

    libthr/thread/thr_join.c: deduplicate backout_join() helper
    
    (cherry picked from commit ce16be73707eedc798b26e0741dcd70d1168ac10)
---
 lib/libthr/thread/thr_join.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/libthr/thread/thr_join.c b/lib/libthr/thread/thr_join.c
index 53f28daa258d..56b316ec0f51 100644
--- a/lib/libthr/thread/thr_join.c
+++ b/lib/libthr/thread/thr_join.c
@@ -43,16 +43,23 @@ __weak_reference(_thr_join, _pthread_join);
 __weak_reference(_pthread_timedjoin_np, pthread_timedjoin_np);
 __weak_reference(_pthread_peekjoin_np, pthread_peekjoin_np);
 
-static void backout_join(void *arg)
+static void
+backout_join(struct pthread *pthread, struct pthread *curthread)
 {
-	struct pthread *pthread = (struct pthread *)arg;
-	struct pthread *curthread = _get_curthread();
-
 	THR_THREAD_LOCK(curthread, pthread);
 	pthread->joiner = NULL;
 	THR_THREAD_UNLOCK(curthread, pthread);
 }
 
+static void
+backout_join_pop(void *arg)
+{
+	struct pthread *pthread = (struct pthread *)arg;
+	struct pthread *curthread = _get_curthread();
+
+	backout_join(pthread, curthread);
+}
+
 int
 _thr_join(pthread_t pthread, void **thread_return)
 {
@@ -149,10 +156,8 @@ join_common(pthread_t pthread, void **thread_return,
 	_thr_cancel_leave(curthread, 0);
 	THR_CLEANUP_POP(curthread, 0);
 
-	if (ret == ETIMEDOUT) {
-		THR_THREAD_LOCK(curthread, pthread);
-		pthread->joiner = NULL;
-		THR_THREAD_UNLOCK(curthread, pthread);
+	if (ret == ETIMEDOUT || ret == EBUSY) {
+		backout_join(pthread, curthread);
 	} else {
 		ret = 0;
 		tmp = pthread->ret;