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-rw-r--r--drivers/oprofile/oprof.c286
1 files changed, 286 insertions, 0 deletions
diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c
new file mode 100644
index 000000000..ed2c3ec07
--- /dev/null
+++ b/drivers/oprofile/oprof.c
@@ -0,0 +1,286 @@
+/**
+ * @file oprof.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/oprofile.h>
+#include <linux/moduleparam.h>
+#include <linux/workqueue.h>
+#include <linux/time.h>
+#include <linux/mutex.h>
+
+#include "oprof.h"
+#include "event_buffer.h"
+#include "cpu_buffer.h"
+#include "buffer_sync.h"
+#include "oprofile_stats.h"
+
+struct oprofile_operations oprofile_ops;
+
+unsigned long oprofile_started;
+unsigned long oprofile_backtrace_depth;
+static unsigned long is_setup;
+static DEFINE_MUTEX(start_mutex);
+
+/* timer
+ 0 - use performance monitoring hardware if available
+ 1 - use the timer int mechanism regardless
+ */
+static int timer = 0;
+
+int oprofile_setup(void)
+{
+ int err;
+
+ mutex_lock(&start_mutex);
+
+ if ((err = alloc_cpu_buffers()))
+ goto out;
+
+ if ((err = alloc_event_buffer()))
+ goto out1;
+
+ if (oprofile_ops.setup && (err = oprofile_ops.setup()))
+ goto out2;
+
+ /* Note even though this starts part of the
+ * profiling overhead, it's necessary to prevent
+ * us missing task deaths and eventually oopsing
+ * when trying to process the event buffer.
+ */
+ if (oprofile_ops.sync_start) {
+ int sync_ret = oprofile_ops.sync_start();
+ switch (sync_ret) {
+ case 0:
+ goto post_sync;
+ case 1:
+ goto do_generic;
+ case -1:
+ goto out3;
+ default:
+ goto out3;
+ }
+ }
+do_generic:
+ if ((err = sync_start()))
+ goto out3;
+
+post_sync:
+ is_setup = 1;
+ mutex_unlock(&start_mutex);
+ return 0;
+
+out3:
+ if (oprofile_ops.shutdown)
+ oprofile_ops.shutdown();
+out2:
+ free_event_buffer();
+out1:
+ free_cpu_buffers();
+out:
+ mutex_unlock(&start_mutex);
+ return err;
+}
+
+#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
+
+static void switch_worker(struct work_struct *work);
+static DECLARE_DELAYED_WORK(switch_work, switch_worker);
+
+static void start_switch_worker(void)
+{
+ if (oprofile_ops.switch_events)
+ schedule_delayed_work(&switch_work, oprofile_time_slice);
+}
+
+static void stop_switch_worker(void)
+{
+ cancel_delayed_work_sync(&switch_work);
+}
+
+static void switch_worker(struct work_struct *work)
+{
+ if (oprofile_ops.switch_events())
+ return;
+
+ atomic_inc(&oprofile_stats.multiplex_counter);
+ start_switch_worker();
+}
+
+/* User inputs in ms, converts to jiffies */
+int oprofile_set_timeout(unsigned long val_msec)
+{
+ int err = 0;
+ unsigned long time_slice;
+
+ mutex_lock(&start_mutex);
+
+ if (oprofile_started) {
+ err = -EBUSY;
+ goto out;
+ }
+
+ if (!oprofile_ops.switch_events) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ time_slice = msecs_to_jiffies(val_msec);
+ if (time_slice == MAX_JIFFY_OFFSET) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ oprofile_time_slice = time_slice;
+
+out:
+ mutex_unlock(&start_mutex);
+ return err;
+
+}
+
+#else
+
+static inline void start_switch_worker(void) { }
+static inline void stop_switch_worker(void) { }
+
+#endif
+
+/* Actually start profiling (echo 1>/dev/oprofile/enable) */
+int oprofile_start(void)
+{
+ int err = -EINVAL;
+
+ mutex_lock(&start_mutex);
+
+ if (!is_setup)
+ goto out;
+
+ err = 0;
+
+ if (oprofile_started)
+ goto out;
+
+ oprofile_reset_stats();
+
+ if ((err = oprofile_ops.start()))
+ goto out;
+
+ start_switch_worker();
+
+ oprofile_started = 1;
+out:
+ mutex_unlock(&start_mutex);
+ return err;
+}
+
+
+/* echo 0>/dev/oprofile/enable */
+void oprofile_stop(void)
+{
+ mutex_lock(&start_mutex);
+ if (!oprofile_started)
+ goto out;
+ oprofile_ops.stop();
+ oprofile_started = 0;
+
+ stop_switch_worker();
+
+ /* wake up the daemon to read what remains */
+ wake_up_buffer_waiter();
+out:
+ mutex_unlock(&start_mutex);
+}
+
+
+void oprofile_shutdown(void)
+{
+ mutex_lock(&start_mutex);
+ if (oprofile_ops.sync_stop) {
+ int sync_ret = oprofile_ops.sync_stop();
+ switch (sync_ret) {
+ case 0:
+ goto post_sync;
+ case 1:
+ goto do_generic;
+ default:
+ goto post_sync;
+ }
+ }
+do_generic:
+ sync_stop();
+post_sync:
+ if (oprofile_ops.shutdown)
+ oprofile_ops.shutdown();
+ is_setup = 0;
+ free_event_buffer();
+ free_cpu_buffers();
+ mutex_unlock(&start_mutex);
+}
+
+int oprofile_set_ulong(unsigned long *addr, unsigned long val)
+{
+ int err = -EBUSY;
+
+ mutex_lock(&start_mutex);
+ if (!oprofile_started) {
+ *addr = val;
+ err = 0;
+ }
+ mutex_unlock(&start_mutex);
+
+ return err;
+}
+
+static int timer_mode;
+
+static int __init oprofile_init(void)
+{
+ int err;
+
+ /* always init architecture to setup backtrace support */
+ timer_mode = 0;
+ err = oprofile_arch_init(&oprofile_ops);
+ if (!err) {
+ if (!timer && !oprofilefs_register())
+ return 0;
+ oprofile_arch_exit();
+ }
+
+ /* setup timer mode: */
+ timer_mode = 1;
+ /* no nmi timer mode if oprofile.timer is set */
+ if (timer || op_nmi_timer_init(&oprofile_ops)) {
+ err = oprofile_timer_init(&oprofile_ops);
+ if (err)
+ return err;
+ }
+
+ return oprofilefs_register();
+}
+
+
+static void __exit oprofile_exit(void)
+{
+ oprofilefs_unregister();
+ if (!timer_mode)
+ oprofile_arch_exit();
+}
+
+
+module_init(oprofile_init);
+module_exit(oprofile_exit);
+
+module_param_named(timer, timer, int, 0644);
+MODULE_PARM_DESC(timer, "force use of timer interrupt");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("John Levon <levon@movementarian.org>");
+MODULE_DESCRIPTION("OProfile system profiler");