powerpc/smp: add generic_set_cpu_up() to set cpu_state as CPU_UP_PREPARE
In the case of cpu hotplug, the cpu_state should be set to CPU_UP_PREPARE
when kicking cpu. Otherwise, the cpu_state is always CPU_DEAD after
calling generic_set_cpu_dead(), which makes the delay in generic_cpu_die()
not happen.
Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 8d4214a..a51ed20 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -102,7 +102,7 @@
* Ok it's not there, so it might be soft-unplugged, let's
* try to bring it back
*/
- per_cpu(cpu_state, nr) = CPU_UP_PREPARE;
+ generic_set_cpu_up(nr);
smp_wmb();
smp_send_reschedule(nr);
#endif /* CONFIG_HOTPLUG_CPU */
@@ -413,6 +413,16 @@
per_cpu(cpu_state, cpu) = CPU_DEAD;
}
+/*
+ * The cpu_state should be set to CPU_UP_PREPARE in kick_cpu(), otherwise
+ * the cpu_state is always CPU_DEAD after calling generic_set_cpu_dead(),
+ * which makes the delay in generic_cpu_die() not happen.
+ */
+void generic_set_cpu_up(unsigned int cpu)
+{
+ per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
+}
+
int generic_check_cpu_restart(unsigned int cpu)
{
return per_cpu(cpu_state, cpu) == CPU_UP_PREPARE;