arm64: smp: fix smp_send_stop() behaviour

[linux.git] / arch / arm64 / kernel / smp.c

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index d4ed9a19d8fe7f8a63946edbfb934bbe8d58a442..e4dc241c5a8e8e4af45d5c3bcefbbfc83255a167 100644 (file)
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -958,11 +958,22 @@ void tick_broadcast(const struct cpumask *mask)
 }
 #endif
 
+/*
+ * The number of CPUs online, not counting this CPU (which may not be
+ * fully online and so not counted in num_online_cpus()).
+ */
+static inline unsigned int num_other_online_cpus(void)
+{
+       unsigned int this_cpu_online = cpu_online(smp_processor_id());
+
+       return num_online_cpus() - this_cpu_online;
+}
+
 void smp_send_stop(void)
 {
        unsigned long timeout;
 
-       if (num_online_cpus() > 1) {
+       if (num_other_online_cpus()) {
                cpumask_t mask;
 
                cpumask_copy(&mask, cpu_online_mask);
@@ -975,10 +986,10 @@ void smp_send_stop(void)
 
        /* Wait up to one second for other CPUs to stop */
        timeout = USEC_PER_SEC;
-       while (num_online_cpus() > 1 && timeout--)
+       while (num_other_online_cpus() && timeout--)
                udelay(1);
 
-       if (num_online_cpus() > 1)
+       if (num_other_online_cpus())
                pr_warn("SMP: failed to stop secondary CPUs %*pbl\n",
                        cpumask_pr_args(cpu_online_mask));