x86: improve UP kernel when CPU-hotplug and SMP is enabled
authorThomas Gleixner <tglx@linutronix.de>
Sun, 5 Oct 2008 14:52:24 +0000 (16:52 +0200)
committerIngo Molnar <mingo@elte.hu>
Mon, 13 Oct 2008 08:33:46 +0000 (10:33 +0200)
commit649c6653fa94ec8f3ea32b19c97b790ec4e8e4ac
treea6c3c0f48147ebcd9eca8d5e0e188f36477705e9
parent8a541665b9063c5006b370d4488cf9f6beb6083f
x86: improve UP kernel when CPU-hotplug and SMP is enabled

num_possible_cpus() can be > 1 when disabled CPUs have been accounted.

Disabled CPUs are not in the cpu_present_map, so we can use
num_present_cpus() as a safe indicator to switch to UP alternatives.

Reported-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/alternative.c