[PATCH] arm64: Support hard limit of cpu count by nr_cpus
From: Kefeng Wang <hidden>
Date: 2016-08-05 06:03:55
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
Enable the hard limit of cpu count by nr_cpus on arm64. The code is borrowed from MIPS. Reported-by: Shiyuan Hu <redacted> Signed-off-by: Kefeng Wang <redacted> --- arch/arm64/kernel/setup.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 536dce2..597b777 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c@@ -224,6 +224,21 @@ static void __init request_standard_resources(void) u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; +static void __init prefill_possible_map(void) +{ + int i, possible = num_possible_cpus(); + + if (possible > nr_cpu_ids) + possible = nr_cpu_ids; + + for (i = 0; i < possible; i++) + set_cpu_possible(i, true); + for (; i < NR_CPUS; i++) + set_cpu_possible(i, false); + + nr_cpu_ids = possible; +} + void __init setup_arch(char **cmdline_p) { pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id());
@@ -285,6 +300,7 @@ void __init setup_arch(char **cmdline_p) cpu_read_bootcpu_ops(); smp_init_cpus(); smp_build_mpidr_hash(); + prefill_possible_map(); #ifdef CONFIG_VT #if defined(CONFIG_VGA_CONSOLE)
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1.7.12.4