LXR linux/arch/x86/oprofile/init.c

   1/**
   2 * @file init.c
   3 *
   4 * @remark Copyright 2002 OProfile authors
   5 * @remark Read the file COPYING
   6 *
   7 * @author John Levon <levon@movementarian.org>
   8 */
   9
  10#include <linux/oprofile.h>
  11#include <linux/init.h>
  12#include <linux/errno.h>
  13
  14/*
  15 * We support CPUs that have performance counters like the Pentium Pro
  16 * with the NMI mode driver.
  17 */
  18
  19extern int op_nmi_init(struct oprofile_operations *ops);
  20extern int op_nmi_timer_init(struct oprofile_operations *ops);
  21extern void op_nmi_exit(void);
  22extern void x86_backtrace(struct pt_regs * const regs, unsigned int depth);
  23
  24static int nmi_timer;
  25
  26int __init oprofile_arch_init(struct oprofile_operations *ops)
  27{
  28        int ret;
  29
  30        ret = -ENODEV;
  31
  32#ifdef CONFIG_X86_LOCAL_APIC
  33        ret = op_nmi_init(ops);
  34#endif
  35        nmi_timer = (ret != 0);
  36#ifdef CONFIG_X86_IO_APIC
  37        if (nmi_timer)
  38                ret = op_nmi_timer_init(ops);
  39#endif
  40        ops->backtrace = x86_backtrace;
  41
  42        return ret;
  43}
  44
  45
  46void oprofile_arch_exit(void)
  47{
  48#ifdef CONFIG_X86_LOCAL_APIC
  49        if (!nmi_timer)
  50                op_nmi_exit();
  51#endif
  52}
  53