linux/drivers/oprofile/cpu_buffer.h
Tejun Heo b3e9f672b6 percpu: make percpu symbols in oprofile unique
This patch updates percpu related symbols in oprofile such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* drivers/oprofile/cpu_buffer.c: s/cpu_buffer/op_cpu_buffer/

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Robert Richter <robert.richter@amd.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-10-29 22:34:13 +09:00

121 lines
2.8 KiB
C

/**
* @file cpu_buffer.h
*
* @remark Copyright 2002-2009 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
* @author Robert Richter <robert.richter@amd.com>
*/
#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;
unsigned long data[0];
};
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;
entry->size--;
entry->data++;
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;
entry->size--;
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)
#endif /* OPROFILE_CPU_BUFFER_H */