Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / kernel / trace / trace_sched_switch.c

diff --git a/kernel/kernel/trace/trace_sched_switch.c b/kernel/kernel/trace/trace_sched_switch.c
new file mode 100644 (file)
index 0000000..419ca37
--- /dev/null
+++ b/kernel/kernel/trace/trace_sched_switch.c
@@ -0,0 +1,101 @@
+/*
+ * trace context switch
+ *
+ * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <trace/events/sched.h>
+
+#include "trace.h"
+
+static int                     sched_ref;
+static DEFINE_MUTEX(sched_register_mutex);
+
+static void
+probe_sched_switch(void *ignore, struct task_struct *prev, struct task_struct *next)
+{
+       if (unlikely(!sched_ref))
+               return;
+
+       tracing_record_cmdline(prev);
+       tracing_record_cmdline(next);
+}
+
+static void
+probe_sched_wakeup(void *ignore, struct task_struct *wakee, int success)
+{
+       if (unlikely(!sched_ref))
+               return;
+
+       tracing_record_cmdline(current);
+}
+
+static int tracing_sched_register(void)
+{
+       int ret;
+
+       ret = register_trace_sched_wakeup(probe_sched_wakeup, NULL);
+       if (ret) {
+               pr_info("wakeup trace: Couldn't activate tracepoint"
+                       " probe to kernel_sched_wakeup\n");
+               return ret;
+       }
+
+       ret = register_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
+       if (ret) {
+               pr_info("wakeup trace: Couldn't activate tracepoint"
+                       " probe to kernel_sched_wakeup_new\n");
+               goto fail_deprobe;
+       }
+
+       ret = register_trace_sched_switch(probe_sched_switch, NULL);
+       if (ret) {
+               pr_info("sched trace: Couldn't activate tracepoint"
+                       " probe to kernel_sched_switch\n");
+               goto fail_deprobe_wake_new;
+       }
+
+       return ret;
+fail_deprobe_wake_new:
+       unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
+fail_deprobe:
+       unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
+       return ret;
+}
+
+static void tracing_sched_unregister(void)
+{
+       unregister_trace_sched_switch(probe_sched_switch, NULL);
+       unregister_trace_sched_wakeup_new(probe_sched_wakeup, NULL);
+       unregister_trace_sched_wakeup(probe_sched_wakeup, NULL);
+}
+
+static void tracing_start_sched_switch(void)
+{
+       mutex_lock(&sched_register_mutex);
+       if (!(sched_ref++))
+               tracing_sched_register();
+       mutex_unlock(&sched_register_mutex);
+}
+
+static void tracing_stop_sched_switch(void)
+{
+       mutex_lock(&sched_register_mutex);
+       if (!(--sched_ref))
+               tracing_sched_unregister();
+       mutex_unlock(&sched_register_mutex);
+}
+
+void tracing_start_cmdline_record(void)
+{
+       tracing_start_sched_switch();
+}
+
+void tracing_stop_cmdline_record(void)
+{
+       tracing_stop_sched_switch();
+}