diff options
Diffstat (limited to 'arch/x86/kernel/smpboot.c')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index be9466788043..1a9941b11150 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1252,6 +1252,15 @@ void __init native_smp_cpus_done(unsigned int max_cpus) check_nmi_watchdog(); } +static int __initdata setup_possible_cpus = -1; +static int __init _setup_possible_cpus(char *str) +{ + get_option(&str, &setup_possible_cpus); + return 0; +} +early_param("possible_cpus", _setup_possible_cpus); + + /* * cpu_possible_map should be static, it cannot change as cpu's * are onlined, or offlined. The reason is per-cpu data-structures @@ -1264,7 +1273,7 @@ void __init native_smp_cpus_done(unsigned int max_cpus) * * Three ways to find out the number of additional hotplug CPUs: * - If the BIOS specified disabled CPUs in ACPI/mptables use that. - * - The user can overwrite it with additional_cpus=NUM + * - The user can overwrite it with possible_cpus=NUM * - Otherwise don't reserve additional CPUs. * We do this because additional CPUs waste a lot of memory. * -AK @@ -1277,9 +1286,17 @@ __init void prefill_possible_map(void) if (!num_processors) num_processors = 1; - possible = num_processors + disabled_cpus; - if (possible > NR_CPUS) - possible = NR_CPUS; + if (setup_possible_cpus == -1) + possible = num_processors + disabled_cpus; + else + possible = setup_possible_cpus; + + if (possible > CONFIG_NR_CPUS) { + printk(KERN_WARNING + "%d Processors exceeds NR_CPUS limit of %d\n", + possible, CONFIG_NR_CPUS); + possible = CONFIG_NR_CPUS; + } printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n", possible, max_t(int, possible - num_processors, 0)); |