From 3908ba2e0b2476e2ec13e15967bf6a37e449f2af Mon Sep 17 00:00:00 2001 From: Nick Hu Date: Wed, 17 Jul 2024 11:17:14 +0800 Subject: [PATCH] RISC-V: Enable the IPI before workqueue_online_cpu() Sometimes the hotplug cpu stalls at the arch_cpu_idle() for a while after workqueue_online_cpu(). When cpu stalls at the idle loop, the reschedule IPI is pending. However the enable bit is not enabled yet so the cpu stalls at WFI until watchdog timeout. Therefore enable the IPI before the workqueue_online_cpu() to fix the issue. Fixes: 63c5484e7495 ("workqueue: Add multiple affinity scopes and interface to select them") Signed-off-by: Nick Hu Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20240717031714.1946036-1-nick.hu@sifive.com Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/sbi-ipi.c | 2 +- include/linux/cpuhotplug.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/sbi-ipi.c b/arch/riscv/kernel/sbi-ipi.c index 1026e22955cc..0cc5559c08d8 100644 --- a/arch/riscv/kernel/sbi-ipi.c +++ b/arch/riscv/kernel/sbi-ipi.c @@ -71,7 +71,7 @@ void __init sbi_ipi_init(void) * the masking/unmasking of virtual IPIs is done * via generic IPI-Mux */ - cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + cpuhp_setup_state(CPUHP_AP_IRQ_RISCV_SBI_IPI_STARTING, "irqchip/sbi-ipi:starting", sbi_ipi_starting_cpu, NULL); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 51ba681b915a..e30d93b807d5 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -148,6 +148,7 @@ enum cpuhp_state { CPUHP_AP_IRQ_LOONGARCH_STARTING, CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING, CPUHP_AP_IRQ_RISCV_IMSIC_STARTING, + CPUHP_AP_IRQ_RISCV_SBI_IPI_STARTING, CPUHP_AP_ARM_MVEBU_COHERENCY, CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING, CPUHP_AP_PERF_X86_STARTING,