From a3313375e88e0075b9048eba15e5eb4dbf93f60e Mon Sep 17 00:00:00 2001 From: Yunhui Cui Date: Mon, 3 Mar 2025 16:34:24 +0800 Subject: [PATCH] riscv: print hartid on bringup Firmware randomly releases cores, so CPU numbers don't linearly map to hartids. When the system has an exception, we care more about hartids. Adding "dyndbg="file smpboot.c +p" loglevel=8" to the cmdline can output the hartid. Signed-off-by: Yunhui Cui Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20250303083424.14309-1-cuiyunhui@bytedance.com Signed-off-by: Alexandre Ghiti --- arch/riscv/kernel/smp.c | 2 ++ arch/riscv/kernel/smpboot.c | 4 ++++ 2 files changed, 6 insertions(+) diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c index d58b5e7512861..e650dec448176 100644 --- a/arch/riscv/kernel/smp.c +++ b/arch/riscv/kernel/smp.c @@ -48,6 +48,8 @@ EXPORT_SYMBOL_GPL(__cpuid_to_hartid_map); void __init smp_setup_processor_id(void) { cpuid_to_hartid_map(0) = boot_cpu_hartid; + + pr_info("Booting Linux on hartid %lu\n", boot_cpu_hartid); } static DEFINE_PER_CPU_READ_MOSTLY(int, ipi_dummy_dev); diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c index e36d20205bd7d..601a321e0f176 100644 --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -231,6 +231,10 @@ asmlinkage __visible void smp_callin(void) riscv_ipi_enable(); numa_add_cpu(curr_cpuid); + + pr_debug("CPU%u: Booted secondary hartid %lu\n", curr_cpuid, + cpuid_to_hartid_map(curr_cpuid)); + set_cpu_online(curr_cpuid, true); /* -- 2.47.2