diff options
| author |   Thomas Gleixner <tglx@linutronix.de> | 2008-10-05 16:52:24 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@elte.hu> | 2008-10-13 10:33:46 +0200 |
| commit | 649c6653fa94ec8f3ea32b19c97b790ec4e8e4ac (patch) | |
| tree | a6c3c0f48147ebcd9eca8d5e0e188f36477705e9 /arch | |
| parent | dumpstack: x86: various small unification steps (diff) | |
| download | linux-dev-649c6653fa94ec8f3ea32b19c97b790ec4e8e4ac.tar.xz linux-dev-649c6653fa94ec8f3ea32b19c97b790ec4e8e4ac.zip | |
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>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/alternative.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index fb04e49776ba..a84ac7b570e6 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -444,7 +444,7 @@ void __init alternative_instructions(void) _text, _etext); /* Only switch to UP mode if we don't immediately boot others */ - if (num_possible_cpus() == 1 || setup_max_cpus <= 1) + if (num_present_cpus() == 1 || setup_max_cpus <= 1) alternatives_smp_switch(0); } #endif |