[PATCH v8 04/10] nmi: backtrace: Allow runtime arch specific override
From: Douglas Anderson
Date: Wed Apr 19 2023 - 18:57:25 EST
From: Sumit Garg <sumit.garg@xxxxxxxxxx>
Add a boolean return to arch_trigger_cpumask_backtrace() to support a
use-case where a particular architecture detects at runtime if it supports
NMI backtrace or it would like to fallback to default implementation using
SMP cross-calls.
Currently such an architecture example is arm64 supporting pseudo NMIs
feature which is only available on platforms which have support for GICv3
or later version.
Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
Tested-by: Chen-Yu Tsai <wens@xxxxxxxx>
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
Changes in v8:
- Add loongarch support, too
arch/arm/include/asm/irq.h | 2 +-
arch/arm/kernel/smp.c | 3 ++-
arch/loongarch/include/asm/irq.h | 2 +-
arch/loongarch/kernel/process.c | 3 ++-
arch/mips/include/asm/irq.h | 2 +-
arch/mips/kernel/process.c | 3 ++-
arch/powerpc/include/asm/nmi.h | 2 +-
arch/powerpc/kernel/stacktrace.c | 3 ++-
arch/sparc/include/asm/irq_64.h | 2 +-
arch/sparc/kernel/process_64.c | 4 +++-
arch/x86/include/asm/irq.h | 2 +-
arch/x86/kernel/apic/hw_nmi.c | 3 ++-
include/linux/nmi.h | 12 ++++--------
13 files changed, 23 insertions(+), 20 deletions(-)
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index a7c2337b0c7d..e6b62c7d6f0e 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -32,7 +32,7 @@ void init_IRQ(void);
#ifdef CONFIG_SMP
#include <linux/cpumask.h>
-extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask,
+extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
#endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 0b8c25763adc..acb97d9219b1 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -849,7 +849,8 @@ static void raise_nmi(cpumask_t *mask)
__ipi_send_mask(ipi_desc[IPI_CPU_BACKTRACE], mask);
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_nmi);
+ return true;
}
diff --git a/arch/loongarch/include/asm/irq.h b/arch/loongarch/include/asm/irq.h
index a115e8999c69..c7a152d6bf0c 100644
--- a/arch/loongarch/include/asm/irq.h
+++ b/arch/loongarch/include/asm/irq.h
@@ -40,7 +40,7 @@ void spurious_interrupt(void);
#define NR_IRQS_LEGACY 16
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
-void arch_trigger_cpumask_backtrace(const struct cpumask *mask, bool exclude_self);
+bool arch_trigger_cpumask_backtrace(const struct cpumask *mask, bool exclude_self);
#define MAX_IO_PICS 2
#define NR_IRQS (64 + (256 * MAX_IO_PICS))
diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c
index fa2443c7afb2..8f7f818f5c4e 100644
--- a/arch/loongarch/kernel/process.c
+++ b/arch/loongarch/kernel/process.c
@@ -339,9 +339,10 @@ static void raise_backtrace(cpumask_t *mask)
}
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace);
+ return true;
}
#ifdef CONFIG_64BIT
diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h
index 44f9824c1d8c..daf16173486a 100644
--- a/arch/mips/include/asm/irq.h
+++ b/arch/mips/include/asm/irq.h
@@ -77,7 +77,7 @@ extern int cp0_fdc_irq;
extern int get_c0_fdc_int(void);
-void arch_trigger_cpumask_backtrace(const struct cpumask *mask,
+bool arch_trigger_cpumask_backtrace(const struct cpumask *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 093dbbd6b843..7d538571830a 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -750,9 +750,10 @@ static void raise_backtrace(cpumask_t *mask)
}
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace);
+ return true;
}
int mips_get_process_fp_mode(struct task_struct *task)
diff --git a/arch/powerpc/include/asm/nmi.h b/arch/powerpc/include/asm/nmi.h
index c3c7adef74de..135f65adcf63 100644
--- a/arch/powerpc/include/asm/nmi.h
+++ b/arch/powerpc/include/asm/nmi.h
@@ -12,7 +12,7 @@ static inline void watchdog_nmi_set_timeout_pct(u64 pct) {}
#endif
#ifdef CONFIG_NMI_IPI
-extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask,
+extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
#endif
diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
index 5de8597eaab8..0fee4bded7ba 100644
--- a/arch/powerpc/kernel/stacktrace.c
+++ b/arch/powerpc/kernel/stacktrace.c
@@ -221,8 +221,9 @@ static void raise_backtrace_ipi(cpumask_t *mask)
}
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace_ipi);
+ return true;
}
#endif /* defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_NMI_IPI) */
diff --git a/arch/sparc/include/asm/irq_64.h b/arch/sparc/include/asm/irq_64.h
index 154df2cf19f4..00a0051a9da0 100644
--- a/arch/sparc/include/asm/irq_64.h
+++ b/arch/sparc/include/asm/irq_64.h
@@ -87,7 +87,7 @@ static inline unsigned long get_softint(void)
return retval;
}
-void arch_trigger_cpumask_backtrace(const struct cpumask *mask,
+bool arch_trigger_cpumask_backtrace(const struct cpumask *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index 91c2b8124527..f9aea1df3adf 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -236,7 +236,7 @@ static void __global_reg_poll(struct global_reg_snapshot *gp)
}
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
struct thread_info *tp = current_thread_info();
struct pt_regs *regs = get_irq_regs();
@@ -291,6 +291,8 @@ void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
+
+ return true;
}
#ifdef CONFIG_MAGIC_SYSRQ
diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index 768aa234cbb4..f731638cc38e 100644
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -43,7 +43,7 @@ extern void init_ISA_irqs(void);
extern void __init init_IRQ(void);
#ifdef CONFIG_X86_LOCAL_APIC
-void arch_trigger_cpumask_backtrace(const struct cpumask *mask,
+bool arch_trigger_cpumask_backtrace(const struct cpumask *mask,
bool exclude_self);
#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c
index 34a992e275ef..e7dcd28bc824 100644
--- a/arch/x86/kernel/apic/hw_nmi.c
+++ b/arch/x86/kernel/apic/hw_nmi.c
@@ -34,10 +34,11 @@ static void nmi_raise_cpu_backtrace(cpumask_t *mask)
apic->send_IPI_mask(mask, NMI_VECTOR);
}
-void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
{
nmi_trigger_cpumask_backtrace(mask, exclude_self,
nmi_raise_cpu_backtrace);
+ return true;
}
static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index 048c0b9aa623..7d8a77cd1e03 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -145,26 +145,22 @@ static inline void touch_nmi_watchdog(void)
#ifdef arch_trigger_cpumask_backtrace
static inline bool trigger_all_cpu_backtrace(void)
{
- arch_trigger_cpumask_backtrace(cpu_online_mask, false);
- return true;
+ return arch_trigger_cpumask_backtrace(cpu_online_mask, false);
}
static inline bool trigger_allbutself_cpu_backtrace(void)
{
- arch_trigger_cpumask_backtrace(cpu_online_mask, true);
- return true;
+ return arch_trigger_cpumask_backtrace(cpu_online_mask, true);
}
static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
{
- arch_trigger_cpumask_backtrace(mask, false);
- return true;
+ return arch_trigger_cpumask_backtrace(mask, false);
}
static inline bool trigger_single_cpu_backtrace(int cpu)
{
- arch_trigger_cpumask_backtrace(cpumask_of(cpu), false);
- return true;
+ return arch_trigger_cpumask_backtrace(cpumask_of(cpu), false);
}
/* generic implementation */
--
2.40.0.634.g4ca3ef3211-goog