Use NMI instead of IPI for CPU stop if RISC-V SSE NMI is supported.
Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
---
arch/riscv/include/asm/smp.h | 2 ++
arch/riscv/kernel/smp.c | 10 +++++++---
drivers/firmware/riscv/riscv_sse_nmi.c | 1 +
3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index f53f1f0e7aa9e..e01ea962adfc4 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -63,6 +63,8 @@ static inline void cpu_crash_stop(unsigned int cpu, struct pt_regs *regs)
}
#endif
+void cpu_stop(void);
+
/* Secondary hart entry */
asmlinkage void smp_callin(void);
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 1b8cf986abbd0..bca95ec0b0f74 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -69,7 +69,7 @@ int riscv_hartid_to_cpuid(unsigned long hartid)
return -ENOENT;
}
-static void ipi_stop(void)
+void cpu_stop(void)
{
set_cpu_online(smp_processor_id(), false);
while (1)
@@ -127,7 +127,7 @@ static irqreturn_t handle_IPI(int irq, void *data)
generic_smp_call_function_interrupt();
break;
case IPI_CPU_STOP:
- ipi_stop();
+ cpu_stop();
break;
case IPI_CPU_CRASH_STOP:
cpu_crash_stop(cpu, get_irq_regs());
@@ -259,7 +259,11 @@ void smp_send_stop(void)
if (system_state <= SYSTEM_RUNNING)
pr_crit("SMP: stopping secondary CPUs\n");
- send_ipi_mask(&mask, IPI_CPU_STOP);
+
+ if (!nmi_support())
+ send_ipi_mask(&mask, IPI_CPU_STOP);
+ else
+ send_nmi_mask(&mask, LOCAL_NMI_CRASH);
}
/* Wait up to one second for other CPUs to stop */
diff --git a/drivers/firmware/riscv/riscv_sse_nmi.c b/drivers/firmware/riscv/riscv_sse_nmi.c
index add028efd25a0..02e2de2bb70f7 100644
--- a/drivers/firmware/riscv/riscv_sse_nmi.c
+++ b/drivers/firmware/riscv/riscv_sse_nmi.c
@@ -58,6 +58,7 @@ static int local_nmi_handler(u32 evt, void *arg, struct pt_regs *regs)
type = atomic_read(this_cpu_ptr(&local_nmi));
NMI_HANDLE(LOCAL_NMI_CRASH, cpu_crash_stop, cpu, regs);
+ NMI_HANDLE(LOCAL_NMI_STOP, cpu_stop);
atomic_andnot(type, this_cpu_ptr(&local_nmi));
--
2.39.5