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Diffstat (limited to 'arch/x86/oprofile/nmi_timer_int.c')
-rw-r--r--arch/x86/oprofile/nmi_timer_int.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/x86/oprofile/nmi_timer_int.c b/arch/x86/oprofile/nmi_timer_int.c
new file mode 100644
index 000000000000..1418e36ae7ab
--- /dev/null
+++ b/arch/x86/oprofile/nmi_timer_int.c
@@ -0,0 +1,69 @@
+/**
+ * @file nmi_timer_int.c
+ *
+ * @remark Copyright 2003 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author Zwane Mwaikambo <zwane@linuxpower.ca>
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/oprofile.h>
+#include <linux/rcupdate.h>
+#include <linux/kdebug.h>
+
+#include <asm/nmi.h>
+#include <asm/apic.h>
+#include <asm/ptrace.h>
+
+static int profile_timer_exceptions_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct die_args *args = (struct die_args *)data;
+ int ret = NOTIFY_DONE;
+
+ switch(val) {
+ case DIE_NMI:
+ oprofile_add_sample(args->regs, 0);
+ ret = NOTIFY_STOP;
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+static struct notifier_block profile_timer_exceptions_nb = {
+ .notifier_call = profile_timer_exceptions_notify,
+ .next = NULL,
+ .priority = 0
+};
+
+static int timer_start(void)
+{
+ if (register_die_notifier(&profile_timer_exceptions_nb))
+ return 1;
+ return 0;
+}
+
+
+static void timer_stop(void)
+{
+ unregister_die_notifier(&profile_timer_exceptions_nb);
+ synchronize_sched(); /* Allow already-started NMIs to complete. */
+}
+
+
+int __init op_nmi_timer_init(struct oprofile_operations * ops)
+{
+ if ((nmi_watchdog != NMI_IO_APIC) || (atomic_read(&nmi_active) <= 0))
+ return -ENODEV;
+
+ ops->start = timer_start;
+ ops->stop = timer_stop;
+ ops->cpu_type = "timer";
+ printk(KERN_INFO "oprofile: using NMI timer interrupt.\n");
+ return 0;
+}