git: 9f78c837d94f - main - check_cancel: when in_sigsuspend, send SIGCANCEL unconditionally

[Konstantin Belousov]

The branch main has been updated by kib:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=9f78c837d94f73f1485e2ce012a8e64197dae9d5

commit 9f78c837d94f73f1485e2ce012a8e64197dae9d5
Author:     Konstantin Belousov <k...@freebsd.org>
AuthorDate: 2024-12-24 00:08:17 +0000
Commit:     Konstantin Belousov <k...@freebsd.org>
CommitDate: 2024-12-28 17:01:58 +0000

    check_cancel: when in_sigsuspend, send SIGCANCEL unconditionally
    
    not only when check_cancel is called from the signal handler.
    _thr_wake() is not enough to get the sigsuspend(2) syscall out of the
    loop, since it only terminates sleep when an unblocked signal is
    delivered.
    
    PR:     283101
    In collaboration with:  pho
    Reviewed by:    markj
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D48200
---
 lib/libthr/thread/thr_sig.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/libthr/thread/thr_sig.c b/lib/libthr/thread/thr_sig.c
index e69641d8e1b5..c5ee5aa8423b 100644
--- a/lib/libthr/thread/thr_sig.c
+++ b/lib/libthr/thread/thr_sig.c
@@ -353,9 +353,11 @@ check_cancel(struct pthread *curthread, ucontext_t *ucp)
         *    on getting a signal before it agrees to return.
         */
        if (curthread->cancel_point) {
-               if (curthread->in_sigsuspend && ucp != NULL) {
-                       SIGADDSET(ucp->uc_sigmask, SIGCANCEL);
-                       curthread->unblock_sigcancel = 1;
+               if (curthread->in_sigsuspend) {
+                       if (ucp != NULL) {
+                               SIGADDSET(ucp->uc_sigmask, SIGCANCEL);
+                               curthread->unblock_sigcancel = 1;
+                       }
                        _thr_send_sig(curthread, SIGCANCEL);
                } else
                        thr_wake(curthread->tid);