drivers/oprofile/cpu_buffer.h

   1 /**
   2  * @file cpu_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 OPROFILE_CPU_BUFFER_H
  11 #define OPROFILE_CPU_BUFFER_H
  12
  13 #include <linux/types.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/cache.h>
  17
  18 struct task_struct;
  19
  20 int alloc_cpu_buffers(void);
  21 void free_cpu_buffers(void);
  22
  23 void start_cpu_work(void);
  24 void end_cpu_work(void);
  25
  26 /* CPU buffer is composed of such entries (which are
  27  * also used for context switch notes)
  28  */
  29 struct op_sample {
  30         unsigned long eip;
  31         unsigned long event;
  32 };
  33
  34 struct oprofile_cpu_buffer {
  35         volatile unsigned long head_pos;
  36         volatile unsigned long tail_pos;
  37         unsigned long buffer_size;
  38         struct task_struct * last_task;
  39         int last_is_kernel;
  40         int tracing;
  41         struct op_sample * buffer;
  42         unsigned long sample_received;
  43         unsigned long sample_lost_overflow;
  44         unsigned long backtrace_aborted;
  45         int cpu;
  46         struct work_struct work;
  47 } ____cacheline_aligned;
  48
  49 extern struct oprofile_cpu_buffer cpu_buffer[];
  50
  51 void cpu_buffer_reset(struct oprofile_cpu_buffer * cpu_buf);
  52
  53 /* transient events for the CPU buffer -> event buffer */
  54 #define CPU_IS_KERNEL 1
  55 #define CPU_TRACE_BEGIN 2
  56
  57 #endif /* OPROFILE_CPU_BUFFER_H */