[PATCH 2/2] kernel/smp: Tell the user we're bringing up secondary CPUs

From: Michael Ellerman
Date: Thu Oct 13 2016 - 04:55:59 EST

Currently we don't print anything before starting to bring up secondary
CPUs. This can be confusing if it takes a long time to bring up the
secondaries, or if the kernel crashes while doing so and produces no
further output.

On x86 they work around this by detecting when the first secondary CPU
comes up and printing a message (see announce_cpu()). But doing it in
smp_init() is simpler and works for all arches.

Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
kernel/smp.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/smp.c b/kernel/smp.c
index 6f5696d260c8..6d9af104de37 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -552,6 +552,8 @@ void __init smp_init(void)

+ pr_info("smp: Bringing up secondary CPUs ...\n");
/* FIXME: This should be done in userspace --RR */
for_each_present_cpu(cpu) {
if (num_online_cpus() >= setup_max_cpus)