[PATCH v3 7/8] riscv: smp: kgdb: use NMI for CPU roundup

Yunhui Cui posted 8 patches 4 days, 9 hours ago
[PATCH v3 7/8] riscv: smp: kgdb: use NMI for CPU roundup
Posted by Yunhui Cui 4 days, 9 hours ago
Use NMI for kgdb CPU roundup if RISC-V SSE NMI is available.

Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
---
 arch/riscv/kernel/smp.c                | 5 ++++-
 drivers/firmware/riscv/riscv_sse_nmi.c | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 6d9a67c2c2a6e..84436e348b6ea 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -368,7 +368,10 @@ void kgdb_roundup_cpus(void)
 		if (cpu == this_cpu)
 			continue;
 
-		send_ipi_single(cpu, IPI_KGDB_ROUNDUP);
+		if (!nmi_support())
+			send_ipi_single(cpu, IPI_KGDB_ROUNDUP);
+		else
+			send_nmi_single(cpu, LOCAL_NMI_KGDB);
 	}
 }
 #endif
diff --git a/drivers/firmware/riscv/riscv_sse_nmi.c b/drivers/firmware/riscv/riscv_sse_nmi.c
index a138d6bdbc0d1..85aa65f31943b 100644
--- a/drivers/firmware/riscv/riscv_sse_nmi.c
+++ b/drivers/firmware/riscv/riscv_sse_nmi.c
@@ -3,6 +3,7 @@
 #define pr_fmt(fmt) "SSE NMI: " fmt
 
 #include <linux/atomic.h>
+#include <linux/kgdb.h>
 #include <linux/nmi.h>
 #include <linux/riscv_sbi_sse.h>
 #include <linux/riscv_sse_nmi.h>
@@ -61,6 +62,7 @@ static int local_nmi_handler(u32 evt, void *arg, struct pt_regs *regs)
 	NMI_HANDLE(LOCAL_NMI_CRASH, cpu_crash_stop, cpu, regs);
 	NMI_HANDLE(LOCAL_NMI_STOP, cpu_stop);
 	NMI_HANDLE(LOCAL_NMI_BACKTRACE, nmi_cpu_backtrace, regs);
+	NMI_HANDLE(LOCAL_NMI_KGDB, kgdb_nmicallback, cpu, regs);
 
 	atomic_andnot(type, this_cpu_ptr(&local_nmi));
 
-- 
2.39.5