blob: aacb0f0bc56682d37aca262f0d72ad135fb7cedc [file] [log] [blame]
/**
* @file cpu_buffer.h
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#ifndef OPROFILE_CPU_BUFFER_H
#define OPROFILE_CPU_BUFFER_H
#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);
/* CPU buffer is composed of such entries (which are
* also used for context switch notes)
*/
struct op_sample {
unsigned long eip;
unsigned long event;
};
struct op_entry {
struct ring_buffer_event *event;
struct op_sample *sample;
unsigned long irq_flags;
};
struct oprofile_cpu_buffer {
volatile unsigned long head_pos;
volatile unsigned long tail_pos;
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;
};
extern struct ring_buffer *op_ring_buffer_read;
extern struct ring_buffer *op_ring_buffer_write;
DECLARE_PER_CPU(struct oprofile_cpu_buffer, 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 cpu_buffer_reset(int cpu)
{
struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu);
cpu_buf->last_is_kernel = -1;
cpu_buf->last_task = NULL;
}
static inline int cpu_buffer_write_entry(struct op_entry *entry)
{
entry->event = ring_buffer_lock_reserve(op_ring_buffer_write,
sizeof(struct op_sample),
&entry->irq_flags);
if (entry->event)
entry->sample = ring_buffer_event_data(entry->event);
else
entry->sample = NULL;
if (!entry->sample)
return -ENOMEM;
return 0;
}
static inline int cpu_buffer_write_commit(struct op_entry *entry)
{
return ring_buffer_unlock_commit(op_ring_buffer_write, entry->event,
entry->irq_flags);
}
static inline struct op_sample *cpu_buffer_read_entry(int cpu)
{
struct ring_buffer_event *e;
e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
if (e)
return ring_buffer_event_data(e);
if (ring_buffer_swap_cpu(op_ring_buffer_read,
op_ring_buffer_write,
cpu))
return NULL;
e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
if (e)
return ring_buffer_event_data(e);
return NULL;
}
/* "acquire" as many cpu buffer slots as we can */
static inline unsigned long cpu_buffer_entries(int cpu)
{
return ring_buffer_entries_cpu(op_ring_buffer_read, cpu)
+ ring_buffer_entries_cpu(op_ring_buffer_write, cpu);
}
/* transient events for the CPU buffer -> event buffer */
#define CPU_IS_KERNEL 1
#define CPU_TRACE_BEGIN 2
#define IBS_FETCH_BEGIN 3
#define IBS_OP_BEGIN 4
#endif /* OPROFILE_CPU_BUFFER_H */