blob: 31478c0cff87ff2f0ab19b47fef4c94f8588fc22 [file] [log] [blame]
* @file cpu_buffer.h
* @remark Copyright 2002-2009 OProfile authors
* @remark Read the file COPYING
* @author John Levon <>
* @author Robert Richter <>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/ring_buffer.h>
struct task_struct;
int alloc_cpu_buffers(void);
void free_cpu_buffers(void);
void start_cpu_work(void);
void end_cpu_work(void);
void flush_cpu_work(void);
/* CPU buffer is composed of such entries (which are
* also used for context switch notes)
struct op_sample {
unsigned long eip;
unsigned long event;
unsigned long data[];
struct op_entry;
struct oprofile_cpu_buffer {
unsigned long buffer_size;
struct task_struct *last_task;
int last_is_kernel;
int tracing;
unsigned long sample_received;
unsigned long sample_lost_overflow;
unsigned long backtrace_aborted;
unsigned long sample_invalid_eip;
int cpu;
struct delayed_work work;
DECLARE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
* Resets the cpu buffer to a sane state.
* reset these to invalid values; the next sample collected will
* populate the buffer with proper values to initialize the buffer
static inline void op_cpu_buffer_reset(int cpu)
struct oprofile_cpu_buffer *cpu_buf = &per_cpu(op_cpu_buffer, cpu);
cpu_buf->last_is_kernel = -1;
cpu_buf->last_task = NULL;
* op_cpu_buffer_add_data() and op_cpu_buffer_write_commit() may be
* called only if op_cpu_buffer_write_reserve() did not return NULL or
* entry->event != NULL, otherwise entry->size or entry->event will be
* used uninitialized.
struct op_sample
*op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
int op_cpu_buffer_write_commit(struct op_entry *entry);
struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu);
unsigned long op_cpu_buffer_entries(int cpu);
/* returns the remaining free size of data in the entry */
static inline
int op_cpu_buffer_add_data(struct op_entry *entry, unsigned long val)
if (!entry->size)
return 0;
*entry->data = val;
return entry->size;
/* returns the size of data in the entry */
static inline
int op_cpu_buffer_get_size(struct op_entry *entry)
return entry->size;
/* returns 0 if empty or the size of data including the current value */
static inline
int op_cpu_buffer_get_data(struct op_entry *entry, unsigned long *val)
int size = entry->size;
if (!size)
return 0;
*val = *entry->data;
return size;
/* extra data flags */
#define KERNEL_CTX_SWITCH (1UL << 0)
#define IS_KERNEL (1UL << 1)
#define TRACE_BEGIN (1UL << 2)
#define USER_CTX_SWITCH (1UL << 3)