svn commit: r367829 - head/sys/kern

[Mateusz Guzik]

Author: mjg
Date: Thu Nov 19 04:27:51 2020
New Revision: 367829
URL: https://svnweb.freebsd.org/changeset/base/367829

Log:
  smp: fix smp_rendezvous_cpus_retry usage before smp starts
  
  Since none of the other CPUs are running there is nobody to clear their
  entries and the routine spins indefinitely.

Modified:
  head/sys/kern/subr_smp.c

Modified: head/sys/kern/subr_smp.c
==============================================================================
--- head/sys/kern/subr_smp.c	Thu Nov 19 03:59:21 2020	(r367828)
+++ head/sys/kern/subr_smp.c	Thu Nov 19 04:27:51 2020	(r367829)
@@ -896,6 +896,21 @@ smp_rendezvous_cpus_retry(cpuset_t map,
 	int cpu;
 
 	/*
+	 * Only one CPU to execute on.
+	 */
+	if (!smp_started) {
+		spinlock_enter();
+		if (setup_func != NULL)
+			setup_func(arg);
+		if (action_func != NULL)
+			action_func(arg);
+		if (teardown_func != NULL)
+			teardown_func(arg);
+		spinlock_exit();
+		return;
+	}
+
+	/*
 	 * Execute an action on all specified CPUs while retrying until they
 	 * all acknowledge completion.
 	 */