LXR linux/arch/ia64/oprofile/perfmon.c

   1/**
   2 * @file perfmon.c
   3 *
   4 * @remark Copyright 2003 OProfile authors
   5 * @remark Read the file COPYING
   6 *
   7 * @author John Levon <levon@movementarian.org>
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/oprofile.h>
  12#include <linux/sched.h>
  13#include <asm/perfmon.h>
  14#include <asm/ptrace.h>
  15#include <asm/errno.h>
  16
  17static int allow_ints;
  18
  19static int
  20perfmon_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg,
  21                struct pt_regs *regs, unsigned long stamp)
  22{
  23        int event = arg->pmd_eventid;
  24 
  25        arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1;
  26
  27        /* the owner of the oprofile event buffer may have exited
  28         * without perfmon being shutdown (e.g. SIGSEGV)
  29         */
  30        if (allow_ints)
  31                oprofile_add_sample(regs, event);
  32        return 0;
  33}
  34
  35
  36static int perfmon_start(void)
  37{
  38        allow_ints = 1;
  39        return 0;
  40}
  41
  42
  43static void perfmon_stop(void)
  44{
  45        allow_ints = 0;
  46}
  47
  48
  49#define OPROFILE_FMT_UUID { \
  50        0x77, 0x7a, 0x6e, 0x61, 0x20, 0x65, 0x73, 0x69, 0x74, 0x6e, 0x72, 0x20, 0x61, 0x65, 0x0a, 0x6c }
  51
  52static pfm_buffer_fmt_t oprofile_fmt = {
  53        .fmt_name           = "oprofile_format",
  54        .fmt_uuid           = OPROFILE_FMT_UUID,
  55        .fmt_handler        = perfmon_handler,
  56};
  57
  58
  59static char *get_cpu_type(void)
  60{
  61        __u8 family = local_cpu_data->family;
  62
  63        switch (family) {
  64                case 0x07:
  65                        return "ia64/itanium";
  66                case 0x1f:
  67                        return "ia64/itanium2";
  68                default:
  69                        return "ia64/ia64";
  70        }
  71}
  72
  73
  74/* all the ops are handled via userspace for IA64 perfmon */
  75
  76static int using_perfmon;
  77
  78int perfmon_init(struct oprofile_operations *ops)
  79{
  80        int ret = pfm_register_buffer_fmt(&oprofile_fmt);
  81        if (ret)
  82                return -ENODEV;
  83
  84        ops->cpu_type = get_cpu_type();
  85        ops->start = perfmon_start;
  86        ops->stop = perfmon_stop;
  87        using_perfmon = 1;
  88        printk(KERN_INFO "oprofile: using perfmon.\n");
  89        return 0;
  90}
  91
  92
  93void perfmon_exit(void)
  94{
  95        if (!using_perfmon)
  96                return;
  97
  98        pfm_unregister_buffer_fmt(oprofile_fmt.fmt_uuid);
  99}
 100