#include <linux/init.h>
#include <linux/oprofile.h>
#include <linux/moduleparam.h>
-#include <linux/workqueue.h>
-#include <linux/time.h>
#include <asm/mutex.h>
#include "oprof.h"
#include "buffer_sync.h"
#include "oprofile_stats.h"
-static unsigned long is_setup;
-static void switch_worker(struct work_struct *work);
-static DECLARE_DELAYED_WORK(switch_work, switch_worker);
-static DEFINE_MUTEX(start_mutex);
-
struct oprofile_operations oprofile_ops;
-unsigned long timeout_jiffies;
unsigned long oprofile_started;
unsigned long backtrace_depth;
-/* Multiplexing defaults at 1 msec*/
+static unsigned long is_setup;
+static DEFINE_MUTEX(start_mutex);
/* timer
0 - use performance monitoring hardware if available
int oprofile_setup(void)
{
int err;
-
+
mutex_lock(&start_mutex);
if ((err = alloc_cpu_buffers()))
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
is_setup = 1;
mutex_unlock(&start_mutex);
return 0;
-
+
out3:
if (oprofile_ops.shutdown)
oprofile_ops.shutdown();
return err;
}
-static void start_switch_worker(void)
-{
- schedule_delayed_work(&switch_work, timeout_jiffies);
-}
-
-static void switch_worker(struct work_struct *work)
-{
- if (!oprofile_ops.switch_events())
- start_switch_worker();
-}
/* 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;
-
+ err = 0;
+
if (oprofile_started)
goto out;
-
+
oprofile_reset_stats();
if ((err = oprofile_ops.start()))
goto out;
- if (oprofile_ops.switch_events)
- start_switch_worker();
-
oprofile_started = 1;
out:
mutex_unlock(&start_mutex);
return err;
}
-
+
/* echo 0>/dev/oprofile/enable */
void oprofile_stop(void)
{
goto out;
oprofile_ops.stop();
oprofile_started = 0;
- cancel_delayed_work_sync(&switch_work);
/* wake up the daemon to read what remains */
wake_up_buffer_waiter();
out:
mutex_unlock(&start_mutex);
}
-/* User inputs in ms, converts to jiffies */
-int oprofile_set_timeout(unsigned long val_msec)
-{
- int err = 0;
-
- mutex_lock(&start_mutex);
-
- if (oprofile_started) {
- err = -EBUSY;
- goto out;
- }
-
- if (!oprofile_ops.switch_events) {
- err = -EINVAL;
- goto out;
- }
-
- timeout_jiffies = msecs_to_jiffies(val_msec);
- if (timeout_jiffies == MAX_JIFFY_OFFSET)
- timeout_jiffies = msecs_to_jiffies(1);
-
-out:
- mutex_unlock(&start_mutex);
- return err;
-
-}
int oprofile_set_backtrace(unsigned long val)
{
return err;
}
-static void __init oprofile_switch_timer_init(void)
-{
- timeout_jiffies = msecs_to_jiffies(1);
-}
-
static int __init oprofile_init(void)
{
int err;
- oprofile_switch_timer_init();
err = oprofile_arch_init(&oprofile_ops);
if (err < 0 || timer) {
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");