swh:1:snp:3c665ee4f67729f27f2e40193ab88e7298cf0fef
Tip revision: 3b2f64d00c46e1e4e9bd0bb9bb12619adac27a4b authored by Linus Torvalds on 21 July 2013, 19:05:29 UTC
Linux 3.11-rc2
Linux 3.11-rc2
Tip revision: 3b2f64d
perfmon.c
/**
* @file perfmon.c
*
* @remark Copyright 2003 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#include <linux/kernel.h>
#include <linux/oprofile.h>
#include <linux/sched.h>
#include <asm/perfmon.h>
#include <asm/ptrace.h>
#include <asm/errno.h>
static int allow_ints;
static int
perfmon_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg,
struct pt_regs *regs, unsigned long stamp)
{
int event = arg->pmd_eventid;
arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1;
/* the owner of the oprofile event buffer may have exited
* without perfmon being shutdown (e.g. SIGSEGV)
*/
if (allow_ints)
oprofile_add_sample(regs, event);
return 0;
}
static int perfmon_start(void)
{
allow_ints = 1;
return 0;
}
static void perfmon_stop(void)
{
allow_ints = 0;
}
#define OPROFILE_FMT_UUID { \
0x77, 0x7a, 0x6e, 0x61, 0x20, 0x65, 0x73, 0x69, 0x74, 0x6e, 0x72, 0x20, 0x61, 0x65, 0x0a, 0x6c }
static pfm_buffer_fmt_t oprofile_fmt = {
.fmt_name = "oprofile_format",
.fmt_uuid = OPROFILE_FMT_UUID,
.fmt_handler = perfmon_handler,
};
static char *get_cpu_type(void)
{
__u8 family = local_cpu_data->family;
switch (family) {
case 0x07:
return "ia64/itanium";
case 0x1f:
return "ia64/itanium2";
default:
return "ia64/ia64";
}
}
/* all the ops are handled via userspace for IA64 perfmon */
static int using_perfmon;
int perfmon_init(struct oprofile_operations *ops)
{
int ret = pfm_register_buffer_fmt(&oprofile_fmt);
if (ret)
return -ENODEV;
ops->cpu_type = get_cpu_type();
ops->start = perfmon_start;
ops->stop = perfmon_stop;
using_perfmon = 1;
printk(KERN_INFO "oprofile: using perfmon.\n");
return 0;
}
void perfmon_exit(void)
{
if (!using_perfmon)
return;
pfm_unregister_buffer_fmt(oprofile_fmt.fmt_uuid);
}