Move a KERNEL_ASSERT_LOCKED() from single_thread_clear() to cursig().

Ze big lock is currently necessary to ensure that two sibling threads
are not racing against each other when processing signals.  However it
is not strickly necessary to unpark sibling threads.

ok claudio@

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index d4f87e7..a0933d9 100644 (file)
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: kern_sig.c,v 1.275 2021/03/08 10:12:05 mpi Exp $      */
+/*     $OpenBSD: kern_sig.c,v 1.276 2021/03/08 10:54:53 mpi Exp $      */
 /*     $NetBSD: kern_sig.c,v 1.54 1996/04/22 01:38:32 christos Exp $   */
 
 /*
@@ -1182,6 +1182,8 @@ cursig(struct proc *p)
        int dolock = (p->p_flag & P_SINTR) == 0;
        int s;
 
+       KERNEL_ASSERT_LOCKED();
+
        sigpending = (p->p_siglist | pr->ps_siglist);
        if (sigpending == 0)
                return 0;
@@ -1225,11 +1227,7 @@ cursig(struct proc *p)
                        if (dolock)
                                SCHED_UNLOCK(s);
 
-                       if (dolock)
-                               KERNEL_LOCK();
                        single_thread_clear(p, 0);
-                       if (dolock)
-                               KERNEL_UNLOCK();
 
                        /*
                         * If we are no longer being traced, or the parent
@@ -2124,7 +2122,6 @@ single_thread_clear(struct proc *p, int flag)
 
        KASSERT(pr->ps_single == p);
        KASSERT(curproc == p);
-       KERNEL_ASSERT_LOCKED();
 
        SCHED_LOCK(s);
        pr->ps_single = NULL;