[PATCH v2 4/4] RISC-V: Support nr_cpus command line option.

From: Atish Patra
Date: Wed Apr 10 2019 - 19:05:05 EST


If nr_cpus command line option is set, maximum possible cpu should be
set to that value.

Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
---
arch/riscv/kernel/smpboot. | 0
arch/riscv/kernel/smpboot.c | 10 +++++++++-
2 files changed, 9 insertions(+), 1 deletion(-)
create mode 100644 arch/riscv/kernel/smpboot.

diff --git a/arch/riscv/kernel/smpboot. b/arch/riscv/kernel/smpboot.
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index a8ad200581aa..7a0b62252524 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -84,11 +84,19 @@ void __init setup_smp(void)
}

cpuid_to_hartid_map(cpuid) = hart;
- set_cpu_possible(cpuid, true);
cpuid++;
}

BUG_ON(!found_boot_cpu);
+
+ if (cpuid > nr_cpu_ids)
+ pr_warn("Total number of cpus [%d] is greater than nr_cpus option value [%d]\n",
+ cpuid, nr_cpu_ids);
+
+ for (cpuid = 1; cpuid < nr_cpu_ids; cpuid++) {
+ if (cpuid_to_hartid_map(cpuid) != INVALID_HARTID)
+ set_cpu_possible(cpuid, true);
+ }
}

int __cpu_up(unsigned int cpu, struct task_struct *tidle)
--
2.21.0