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-rw-r--r--kernel/trace/trace_preemptirq.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c
new file mode 100644
index 000000000..1e130da1b
--- /dev/null
+++ b/kernel/trace/trace_preemptirq.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * preemptoff and irqoff tracepoints
+ *
+ * Copyright (C) Joel Fernandes (Google) <joel@joelfernandes.org>
+ */
+
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/ftrace.h>
+#include <linux/kprobes.h>
+#include "trace.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/preemptirq.h>
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+/* Per-cpu variable to prevent redundant calls when IRQs already off */
+static DEFINE_PER_CPU(int, tracing_irq_cpu);
+
+/*
+ * Like trace_hardirqs_on() but without the lockdep invocation. This is
+ * used in the low level entry code where the ordering vs. RCU is important
+ * and lockdep uses a staged approach which splits the lockdep hardirq
+ * tracking into a RCU on and a RCU off section.
+ */
+void trace_hardirqs_on_prepare(void)
+{
+ if (this_cpu_read(tracing_irq_cpu)) {
+ if (!in_nmi())
+ trace_irq_enable(CALLER_ADDR0, CALLER_ADDR1);
+ tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1);
+ this_cpu_write(tracing_irq_cpu, 0);
+ }
+}
+EXPORT_SYMBOL(trace_hardirqs_on_prepare);
+NOKPROBE_SYMBOL(trace_hardirqs_on_prepare);
+
+void trace_hardirqs_on(void)
+{
+ if (this_cpu_read(tracing_irq_cpu)) {
+ if (!in_nmi())
+ trace_irq_enable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
+ tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1);
+ this_cpu_write(tracing_irq_cpu, 0);
+ }
+
+ lockdep_hardirqs_on_prepare();
+ lockdep_hardirqs_on(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_on);
+NOKPROBE_SYMBOL(trace_hardirqs_on);
+
+/*
+ * Like trace_hardirqs_off() but without the lockdep invocation. This is
+ * used in the low level entry code where the ordering vs. RCU is important
+ * and lockdep uses a staged approach which splits the lockdep hardirq
+ * tracking into a RCU on and a RCU off section.
+ */
+void trace_hardirqs_off_finish(void)
+{
+ if (!this_cpu_read(tracing_irq_cpu)) {
+ this_cpu_write(tracing_irq_cpu, 1);
+ tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
+ if (!in_nmi())
+ trace_irq_disable(CALLER_ADDR0, CALLER_ADDR1);
+ }
+
+}
+EXPORT_SYMBOL(trace_hardirqs_off_finish);
+NOKPROBE_SYMBOL(trace_hardirqs_off_finish);
+
+void trace_hardirqs_off(void)
+{
+ lockdep_hardirqs_off(CALLER_ADDR0);
+
+ if (!this_cpu_read(tracing_irq_cpu)) {
+ this_cpu_write(tracing_irq_cpu, 1);
+ tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
+ if (!in_nmi())
+ trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
+ }
+}
+EXPORT_SYMBOL(trace_hardirqs_off);
+NOKPROBE_SYMBOL(trace_hardirqs_off);
+
+__visible void trace_hardirqs_on_caller(unsigned long caller_addr)
+{
+ if (this_cpu_read(tracing_irq_cpu)) {
+ if (!in_nmi())
+ trace_irq_enable_rcuidle(CALLER_ADDR0, caller_addr);
+ tracer_hardirqs_on(CALLER_ADDR0, caller_addr);
+ this_cpu_write(tracing_irq_cpu, 0);
+ }
+
+ lockdep_hardirqs_on_prepare();
+ lockdep_hardirqs_on(caller_addr);
+}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+NOKPROBE_SYMBOL(trace_hardirqs_on_caller);
+
+__visible void trace_hardirqs_off_caller(unsigned long caller_addr)
+{
+ lockdep_hardirqs_off(caller_addr);
+
+ if (!this_cpu_read(tracing_irq_cpu)) {
+ this_cpu_write(tracing_irq_cpu, 1);
+ tracer_hardirqs_off(CALLER_ADDR0, caller_addr);
+ if (!in_nmi())
+ trace_irq_disable_rcuidle(CALLER_ADDR0, caller_addr);
+ }
+}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+NOKPROBE_SYMBOL(trace_hardirqs_off_caller);
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+#ifdef CONFIG_TRACE_PREEMPT_TOGGLE
+
+void trace_preempt_on(unsigned long a0, unsigned long a1)
+{
+ if (!in_nmi())
+ trace_preempt_enable_rcuidle(a0, a1);
+ tracer_preempt_on(a0, a1);
+}
+
+void trace_preempt_off(unsigned long a0, unsigned long a1)
+{
+ if (!in_nmi())
+ trace_preempt_disable_rcuidle(a0, a1);
+ tracer_preempt_off(a0, a1);
+}
+#endif