From: Daniel Thompson <daniel.thompson@linaro.org>
To: linux-arm-kernel@lists.infradead.org
Cc: Daniel Thompson <daniel.thompson@linaro.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
linux-kernel@vger.kernel.org, patches@linaro.org,
linaro-kernel@lists.linaro.org,
John Stultz <john.stultz@linaro.org>,
Sumit Semwal <sumit.semwal@linaro.org>,
Marc Zyngier <marc.zyngier@arm.com>,
Andrew Thoelke <andrew.thoelke@arm.com>,
Dave Martin <dave.martin@arm.com>,
Russell King <rmk+kernel@arm.linux.org.uk>
Subject: [RFC PATCH v2 2/7] arm64: Add support for on-demand backtrace of other CPUs
Date: Mon, 14 Sep 2015 14:26:16 +0100 [thread overview]
Message-ID: <1442237181-17064-3-git-send-email-daniel.thompson@linaro.org> (raw)
In-Reply-To: <1442237181-17064-1-git-send-email-daniel.thompson@linaro.org>
Currently arm64 has no implementation of arch_trigger_all_cpu_backtace.
The patch provides one using library code recently added by Russell King
for for the majority of the implementation. Currently this is realized
using regular irqs but could, in the future, be implemented using
NMI-like mechanisms.
Note: There is a small (and nasty) change to the generic code to ensure
good stack traces. The generic code currently assumes that
show_regs() will include a stack trace but arch/arm64 does not do
this so we must add extra code here. Ideas on a better approach
here would be very welcome (is there any appetite to change arm64
show_regs() or should we just tease out the dump code into a
callback?).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm64/include/asm/hardirq.h | 2 +-
arch/arm64/include/asm/irq.h | 3 +++
arch/arm64/kernel/smp.c | 26 ++++++++++++++++++++++++++
lib/nmi_backtrace.c | 8 ++++++--
4 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h
index 2bb7009bdac7..0af4cdb4b5a9 100644
--- a/arch/arm64/include/asm/hardirq.h
+++ b/arch/arm64/include/asm/hardirq.h
@@ -20,7 +20,7 @@
#include <linux/threads.h>
#include <asm/irq.h>
-#define NR_IPI 5
+#define NR_IPI 6
typedef struct {
unsigned int __softirq_pending;
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index bbb251b14746..6b2724b2a803 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -21,4 +21,7 @@ static inline void acpi_irq_init(void)
}
#define acpi_irq_init acpi_irq_init
+extern void arch_trigger_all_cpu_backtrace(bool);
+#define arch_trigger_all_cpu_backtrace(x) arch_trigger_all_cpu_backtrace(x)
+
#endif
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index dbdaacddd9a5..0f37a33499e2 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -37,6 +37,7 @@
#include <linux/completion.h>
#include <linux/of.h>
#include <linux/irq_work.h>
+#include <linux/nmi.h>
#include <asm/alternative.h>
#include <asm/atomic.h>
@@ -70,6 +71,7 @@ enum ipi_msg_type {
IPI_CPU_STOP,
IPI_TIMER,
IPI_IRQ_WORK,
+ IPI_CPU_BACKTRACE,
};
/*
@@ -623,6 +625,7 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = {
S(IPI_CPU_STOP, "CPU stop interrupts"),
S(IPI_TIMER, "Timer broadcast interrupts"),
S(IPI_IRQ_WORK, "IRQ work interrupts"),
+ S(IPI_CPU_BACKTRACE, "backtrace interrupts"),
};
static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
@@ -743,6 +746,12 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
break;
#endif
+ case IPI_CPU_BACKTRACE:
+ irq_enter();
+ nmi_cpu_backtrace(regs);
+ irq_exit();
+ break;
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
break;
@@ -794,3 +803,20 @@ int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
+
+static void raise_nmi(cpumask_t *mask)
+{
+ /*
+ * Generate the backtrace directly if we are running in a
+ * calling context that is not preemptible by the backtrace IPI.
+ */
+ if (cpumask_test_cpu(smp_processor_id(), mask) && irqs_disabled())
+ nmi_cpu_backtrace(NULL);
+
+ smp_cross_call(mask, IPI_CPU_BACKTRACE);
+}
+
+void arch_trigger_all_cpu_backtrace(bool include_self)
+{
+ nmi_trigger_all_cpu_backtrace(include_self, raise_nmi);
+}
diff --git a/lib/nmi_backtrace.c b/lib/nmi_backtrace.c
index be0466a80d0b..29f7c4585f7f 100644
--- a/lib/nmi_backtrace.c
+++ b/lib/nmi_backtrace.c
@@ -149,10 +149,14 @@ bool nmi_cpu_backtrace(struct pt_regs *regs)
/* Replace printk to write into the NMI seq */
this_cpu_write(printk_func, nmi_vprintk);
pr_warn("NMI backtrace for cpu %d\n", cpu);
- if (regs)
+ if (regs) {
show_regs(regs);
- else
+#ifdef CONFIG_ARM64
+ show_stack(NULL, NULL);
+#endif
+ } else {
dump_stack();
+ }
this_cpu_write(printk_func, printk_func_save);
cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
--
2.4.3
WARNING: multiple messages have this Message-ID (diff)
From: daniel.thompson@linaro.org (Daniel Thompson)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH v2 2/7] arm64: Add support for on-demand backtrace of other CPUs
Date: Mon, 14 Sep 2015 14:26:16 +0100 [thread overview]
Message-ID: <1442237181-17064-3-git-send-email-daniel.thompson@linaro.org> (raw)
In-Reply-To: <1442237181-17064-1-git-send-email-daniel.thompson@linaro.org>
Currently arm64 has no implementation of arch_trigger_all_cpu_backtace.
The patch provides one using library code recently added by Russell King
for for the majority of the implementation. Currently this is realized
using regular irqs but could, in the future, be implemented using
NMI-like mechanisms.
Note: There is a small (and nasty) change to the generic code to ensure
good stack traces. The generic code currently assumes that
show_regs() will include a stack trace but arch/arm64 does not do
this so we must add extra code here. Ideas on a better approach
here would be very welcome (is there any appetite to change arm64
show_regs() or should we just tease out the dump code into a
callback?).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm64/include/asm/hardirq.h | 2 +-
arch/arm64/include/asm/irq.h | 3 +++
arch/arm64/kernel/smp.c | 26 ++++++++++++++++++++++++++
lib/nmi_backtrace.c | 8 ++++++--
4 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h
index 2bb7009bdac7..0af4cdb4b5a9 100644
--- a/arch/arm64/include/asm/hardirq.h
+++ b/arch/arm64/include/asm/hardirq.h
@@ -20,7 +20,7 @@
#include <linux/threads.h>
#include <asm/irq.h>
-#define NR_IPI 5
+#define NR_IPI 6
typedef struct {
unsigned int __softirq_pending;
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index bbb251b14746..6b2724b2a803 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -21,4 +21,7 @@ static inline void acpi_irq_init(void)
}
#define acpi_irq_init acpi_irq_init
+extern void arch_trigger_all_cpu_backtrace(bool);
+#define arch_trigger_all_cpu_backtrace(x) arch_trigger_all_cpu_backtrace(x)
+
#endif
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index dbdaacddd9a5..0f37a33499e2 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -37,6 +37,7 @@
#include <linux/completion.h>
#include <linux/of.h>
#include <linux/irq_work.h>
+#include <linux/nmi.h>
#include <asm/alternative.h>
#include <asm/atomic.h>
@@ -70,6 +71,7 @@ enum ipi_msg_type {
IPI_CPU_STOP,
IPI_TIMER,
IPI_IRQ_WORK,
+ IPI_CPU_BACKTRACE,
};
/*
@@ -623,6 +625,7 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = {
S(IPI_CPU_STOP, "CPU stop interrupts"),
S(IPI_TIMER, "Timer broadcast interrupts"),
S(IPI_IRQ_WORK, "IRQ work interrupts"),
+ S(IPI_CPU_BACKTRACE, "backtrace interrupts"),
};
static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
@@ -743,6 +746,12 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
break;
#endif
+ case IPI_CPU_BACKTRACE:
+ irq_enter();
+ nmi_cpu_backtrace(regs);
+ irq_exit();
+ break;
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
break;
@@ -794,3 +803,20 @@ int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
+
+static void raise_nmi(cpumask_t *mask)
+{
+ /*
+ * Generate the backtrace directly if we are running in a
+ * calling context that is not preemptible by the backtrace IPI.
+ */
+ if (cpumask_test_cpu(smp_processor_id(), mask) && irqs_disabled())
+ nmi_cpu_backtrace(NULL);
+
+ smp_cross_call(mask, IPI_CPU_BACKTRACE);
+}
+
+void arch_trigger_all_cpu_backtrace(bool include_self)
+{
+ nmi_trigger_all_cpu_backtrace(include_self, raise_nmi);
+}
diff --git a/lib/nmi_backtrace.c b/lib/nmi_backtrace.c
index be0466a80d0b..29f7c4585f7f 100644
--- a/lib/nmi_backtrace.c
+++ b/lib/nmi_backtrace.c
@@ -149,10 +149,14 @@ bool nmi_cpu_backtrace(struct pt_regs *regs)
/* Replace printk to write into the NMI seq */
this_cpu_write(printk_func, nmi_vprintk);
pr_warn("NMI backtrace for cpu %d\n", cpu);
- if (regs)
+ if (regs) {
show_regs(regs);
- else
+#ifdef CONFIG_ARM64
+ show_stack(NULL, NULL);
+#endif
+ } else {
dump_stack();
+ }
this_cpu_write(printk_func, printk_func_save);
cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
--
2.4.3
next prev parent reply other threads:[~2015-09-14 13:26 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-14 13:26 [RFC PATCH v2 0/7] Pseudo-NMI for arm64 using ICC_PMR_EL1 (GICv3) Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-14 13:26 ` [RFC PATCH v2 1/7] irqchip: gic-v3: Reset BPR during initialization Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson [this message]
2015-09-14 13:26 ` [RFC PATCH v2 2/7] arm64: Add support for on-demand backtrace of other CPUs Daniel Thompson
2015-09-14 13:26 ` [RFC PATCH v2 3/7] arm64: alternative: Apply alternatives early in boot process Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-16 13:05 ` Will Deacon
2015-09-16 13:05 ` Will Deacon
2015-09-16 15:51 ` Daniel Thompson
2015-09-16 15:51 ` Daniel Thompson
2015-09-16 16:24 ` Will Deacon
2015-09-16 16:24 ` Will Deacon
2015-09-17 13:25 ` Daniel Thompson
2015-09-17 13:25 ` Daniel Thompson
2015-09-17 14:01 ` Will Deacon
2015-09-17 14:01 ` Will Deacon
2015-09-17 15:28 ` Daniel Thompson
2015-09-17 15:28 ` Daniel Thompson
2015-09-17 15:43 ` Will Deacon
2015-09-17 15:43 ` Will Deacon
2015-09-14 13:26 ` [RFC PATCH v2 4/7] arm64: irqflags: Reorder the fiq & async macros Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-14 13:26 ` [RFC PATCH v2 5/7] arm64: irqflags: Use ICC sysregs to implement IRQ masking Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-14 13:26 ` [RFC PATCH v2 6/7] arm64: Implement IPI_CPU_BACKTRACE using pseudo-NMIs Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-14 13:26 ` [RFC PATCH v2 7/7] arm64: irqflags: Automatically identify I bit mis-management Daniel Thompson
2015-09-14 13:26 ` Daniel Thompson
2015-09-18 5:11 ` [RFC PATCH v2 0/7] Pseudo-NMI for arm64 using ICC_PMR_EL1 (GICv3) Jon Masters
2015-09-18 5:11 ` Jon Masters
2015-09-18 11:23 ` Daniel Thompson
2015-09-18 11:23 ` Daniel Thompson
2015-09-22 18:08 ` 答复: " Dingtianhong
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