From 2b633e3fac5efada088b57d31e65401f22bcc18f Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 10 Feb 2010 01:20:37 -0800 Subject: smp: Use nr_cpus= to set nr_cpu_ids early On x86, before prefill_possible_map(), nr_cpu_ids will be NR_CPUS aka CONFIG_NR_CPUS. Add nr_cpus= to set nr_cpu_ids. so we can simulate cpus <=8 are installed on normal config. -v2: accordging to Christoph, acpi_numa_init should use nr_cpu_ids in stead of NR_CPUS. -v3: add doc in kernel-parameters.txt according to Andrew. Signed-off-by: Yinghai Lu LKML-Reference: <1265793639-15071-34-git-send-email-yinghai@kernel.org> Acked-by: Linus Torvalds Signed-off-by: H. Peter Anvin Cc: Tony Luck --- arch/x86/kernel/smpboot.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/smpboot.c') diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 678d0b8c26f3..eff2fe175422 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1213,11 +1213,12 @@ __init void prefill_possible_map(void) total_cpus = max_t(int, possible, num_processors + disabled_cpus); - if (possible > CONFIG_NR_CPUS) { + /* nr_cpu_ids could be reduced via nr_cpus= */ + if (possible > nr_cpu_ids) { printk(KERN_WARNING "%d Processors exceeds NR_CPUS limit of %d\n", - possible, CONFIG_NR_CPUS); - possible = CONFIG_NR_CPUS; + possible, nr_cpu_ids); + possible = nr_cpu_ids; } printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n", -- cgit v1.2.3