From 44dbcc93ab67145bf8ebe3e91123303443c4a3bf Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Fri, 22 Apr 2016 12:25:35 +0100 Subject: [PATCH] arm64: Fix behavior of maxcpus=N maxcpu=n sets the number of CPUs activated at boot time to a max of n, but allowing the remaining CPUs to be brought up later if the user decides to do so. However, on arm64 due to various reasons, we disallowed hotplugging CPUs beyond n, by marking them not present. Now that we have checks in place to make sure the hotplugged CPUs have compatible features with system and requires no new errata, relax the restriction. Cc: Will Deacon Cc: Mark Rutland Cc: James Morse Reviewed-by: Catalin Marinas Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon --- arch/arm64/kernel/smp.c | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index fef2e7337fc7..dc9647521c59 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -689,33 +689,18 @@ void __init smp_init_cpus(void) void __init smp_prepare_cpus(unsigned int max_cpus) { int err; - unsigned int cpu, ncores = num_possible_cpus(); + unsigned int cpu; init_cpu_topology(); smp_store_cpu_info(smp_processor_id()); - /* - * are we trying to boot more cores than exist? - */ - if (max_cpus > ncores) - max_cpus = ncores; - - /* Don't bother if we're effectively UP */ - if (max_cpus <= 1) - return; - /* * Initialise the present map (which describes the set of CPUs * actually populated at the present time) and release the * secondaries from the bootloader. - * - * Make sure we online at most (max_cpus - 1) additional CPUs. */ - max_cpus--; for_each_possible_cpu(cpu) { - if (max_cpus == 0) - break; if (cpu == smp_processor_id()) continue; @@ -728,7 +713,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus) continue; set_cpu_present(cpu, true); - max_cpus--; } } -- 2.20.1