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Diffstat (limited to 'drivers/oprofile/timer_int.c')
-rw-r--r--drivers/oprofile/timer_int.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/oprofile/timer_int.c b/drivers/oprofile/timer_int.c
new file mode 100644
index 000000000..bdef916e5
--- /dev/null
+++ b/drivers/oprofile/timer_int.c
@@ -0,0 +1,120 @@
+/**
+ * @file timer_int.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/smp.h>
+#include <linux/oprofile.h>
+#include <linux/profile.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/hrtimer.h>
+#include <asm/irq_regs.h>
+#include <asm/ptrace.h>
+
+#include "oprof.h"
+
+static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
+static int ctr_running;
+
+static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
+{
+ oprofile_add_sample(get_irq_regs(), 0);
+ hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
+ return HRTIMER_RESTART;
+}
+
+static void __oprofile_hrtimer_start(void *unused)
+{
+ struct hrtimer *hrtimer = this_cpu_ptr(&oprofile_hrtimer);
+
+ if (!ctr_running)
+ return;
+
+ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer->function = oprofile_hrtimer_notify;
+
+ hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
+ HRTIMER_MODE_REL_PINNED);
+}
+
+static int oprofile_hrtimer_start(void)
+{
+ get_online_cpus();
+ ctr_running = 1;
+ on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
+ put_online_cpus();
+ return 0;
+}
+
+static void __oprofile_hrtimer_stop(int cpu)
+{
+ struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
+
+ if (!ctr_running)
+ return;
+
+ hrtimer_cancel(hrtimer);
+}
+
+static void oprofile_hrtimer_stop(void)
+{
+ int cpu;
+
+ get_online_cpus();
+ for_each_online_cpu(cpu)
+ __oprofile_hrtimer_stop(cpu);
+ ctr_running = 0;
+ put_online_cpus();
+}
+
+static int oprofile_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ long cpu = (long) hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ smp_call_function_single(cpu, __oprofile_hrtimer_start,
+ NULL, 1);
+ break;
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ __oprofile_hrtimer_stop(cpu);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __refdata oprofile_cpu_notifier = {
+ .notifier_call = oprofile_cpu_notify,
+};
+
+static int oprofile_hrtimer_setup(void)
+{
+ return register_hotcpu_notifier(&oprofile_cpu_notifier);
+}
+
+static void oprofile_hrtimer_shutdown(void)
+{
+ unregister_hotcpu_notifier(&oprofile_cpu_notifier);
+}
+
+int oprofile_timer_init(struct oprofile_operations *ops)
+{
+ ops->create_files = NULL;
+ ops->setup = oprofile_hrtimer_setup;
+ ops->shutdown = oprofile_hrtimer_shutdown;
+ ops->start = oprofile_hrtimer_start;
+ ops->stop = oprofile_hrtimer_stop;
+ ops->cpu_type = "timer";
+ printk(KERN_INFO "oprofile: using timer interrupt.\n");
+ return 0;
+}