From ab3d26500547369c24a6c1c31725fd2841a57d0c Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Wed, 24 Apr 2019 14:47:59 -0700 Subject: [PATCH] RISC-V: Implement nosmp commandline option. nosmp command line option sets max_cpus to zero. No secondary harts will boot if this is enabled. But present cpu mask will still point to all possible masks. Fix present cpu mask for nosmp usecase. Signed-off-by: Atish Patra Reviewed-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/smpboot.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c index eb533b5c2c8c..a8ad200581aa 100644 --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -47,6 +47,17 @@ void __init smp_prepare_boot_cpu(void) void __init smp_prepare_cpus(unsigned int max_cpus) { + int cpuid; + + /* This covers non-smp usecase mandated by "nosmp" option */ + if (max_cpus == 0) + return; + + for_each_possible_cpu(cpuid) { + if (cpuid == smp_processor_id()) + continue; + set_cpu_present(cpuid, true); + } } void __init setup_smp(void) @@ -74,7 +85,6 @@ void __init setup_smp(void) cpuid_to_hartid_map(cpuid) = hart; set_cpu_possible(cpuid, true); - set_cpu_present(cpuid, true); cpuid++; } -- 2.30.2