drivers/oprofile/event_buffer.h

   1 /**
   2  * @file event_buffer.h
   3  *
   4  * @remark Copyright 2002 OProfile authors
   5  * @remark Read the file COPYING
   6  *
   7  * @author John Levon <levon@movementarian.org>
   8  */
   9
  10 #ifndef EVENT_BUFFER_H
  11 #define EVENT_BUFFER_H
  12
  13 #include <linux/types.h>
  14 #include <asm/semaphore.h>
  15
  16 int alloc_event_buffer(void);
  17
  18 void free_event_buffer(void);
  19
  20 /* wake up the process sleeping on the event file */
  21 void wake_up_buffer_waiter(void);
  22
  23 /* Each escaped entry is prefixed by ESCAPE_CODE
  24  * then one of the following codes, then the
  25  * relevant data.
  26  */
  27 #define ESCAPE_CODE                     ~0UL
  28 #define CTX_SWITCH_CODE                 1
  29 #define CPU_SWITCH_CODE                 2
  30 #define COOKIE_SWITCH_CODE              3
  31 #define KERNEL_ENTER_SWITCH_CODE        4
  32 #define KERNEL_EXIT_SWITCH_CODE         5
  33 #define MODULE_LOADED_CODE              6
  34 #define CTX_TGID_CODE                   7
  35 #define TRACE_BEGIN_CODE                8
  36 #define TRACE_END_CODE                  9
  37
  38 #define INVALID_COOKIE ~0UL
  39 #define NO_COOKIE 0UL
  40
  41 /* add data to the event buffer */
  42 void add_event_entry(unsigned long data);
  43
  44 extern struct file_operations event_buffer_fops;
  45
  46 /* mutex between sync_cpu_buffers() and the
  47  * file reading code.
  48  */
  49 extern struct semaphore buffer_sem;
  50
  51 #endif /* EVENT_BUFFER_H */