cpu/hotplug: Handle early registration gracefully
We switched the hotplug machinery to smpboot threads. Early registration of
hotplug callbacks, i.e. from do_pre_smp_initcalls(), happens before the
threads are initialized. Instead of moving the thread init, we simply handle
it in the hotplug code itself and invoke the function directly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153332.896450738@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 7b61887..fe71ce4 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -517,6 +517,13 @@
if (!cpu_online(cpu))
return 0;
+ /*
+ * If we are up and running, use the hotplug thread. For early calls
+ * we invoke the thread function directly.
+ */
+ if (!st->thread)
+ return cpuhp_invoke_callback(cpu, state, cb);
+
st->cb_state = state;
st->cb = cb;
/*
