kernel/linux/arch/arm/oprofile/common.c

   1 /**
   2  * @file common.c
   3  *
   4  * @remark Copyright 2004 Oprofile Authors
   5  * @remark Read the file COPYING
   6  *
   7  * @author Zwane Mwaikambo
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/oprofile.h>
  12 #include <linux/errno.h>
  13 #include <asm/semaphore.h>
  14
  15 #include "op_counter.h"
  16 #include "op_arm_model.h"
  17
  18 static struct op_arm_model_spec *pmu_model;
  19 static int pmu_enabled;
  20 static struct semaphore pmu_sem;
  21
  22 static int pmu_start(void);
  23 static int pmu_setup(void);
  24 static void pmu_stop(void);
  25 static int pmu_create_files(struct super_block *, struct dentry *);
  26
  27 static struct oprofile_operations pmu_ops = {
  28         .create_files   = pmu_create_files,
  29         .setup          = pmu_setup,
  30         .shutdown       = pmu_stop,
  31         .start          = pmu_start,
  32         .stop           = pmu_stop,
  33 };
  34
  35 #ifdef CONFIG_PM
  36 static struct sys_device device_oprofile = {
  37         .id             = 0,
  38         .cls            = &oprofile_sysclass,
  39 };
  40
  41 static int __init init_driverfs(void)
  42 {
  43         int ret;
  44
  45         if (!(ret = sysdev_class_register(&oprofile_sysclass)))
  46                 ret = sys_device_register(&device_oprofile);
  47
  48         return ret;
  49 }
  50
  51 static void __exit exit_driverfs(void)
  52 {
  53         sys_device_unregister(&device_oprofile);
  54         sysdev_class_unregister(&oprofile_sysclass);
  55 }
  56 #else
  57 #define init_driverfs() do { } while (0)
  58 #define exit_driverfs() do { } while (0)
  59 #endif /* CONFIG_PM */
  60
  61 struct op_counter_config counter_config[OP_MAX_COUNTER];
  62
  63 static int pmu_create_files(struct super_block *sb, struct dentry *root)
  64 {
  65         unsigned int i;
  66
  67         for (i = 0; i < pmu_model->num_counters; i++) {
  68                 struct dentry *dir;
  69                 char buf[2];
  70
  71                 snprintf(buf, sizeof buf, "%d", i);
  72                 dir = oprofilefs_mkdir(sb, root, buf);
  73                 oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
  74                 oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
  75                 oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
  76                 oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
  77                 oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
  78                 oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
  79         }
  80
  81         return 0;
  82 }
  83
  84 static int pmu_setup(void)
  85 {
  86         int ret;
  87
  88         spin_lock(&oprofilefs_lock);
  89         ret = pmu_model->setup_ctrs();
  90         spin_unlock(&oprofilefs_lock);
  91         return ret;
  92 }
  93
  94 static int pmu_start(void)
  95 {
  96         int ret = -EBUSY;
  97
  98         down(&pmu_sem);
  99         if (!pmu_enabled) {
 100                 ret = pmu_model->start();
 101                 pmu_enabled = !ret;
 102         }
 103         up(&pmu_sem);
 104         return ret;
 105 }
 106
 107 static void pmu_stop(void)
 108 {
 109         down(&pmu_sem);
 110         if (pmu_enabled)
 111                 pmu_model->stop();
 112         pmu_enabled = 0;
 113         up(&pmu_sem);
 114 }
 115
 116 int __init pmu_init(struct oprofile_operations **ops, struct op_arm_model_spec *spec)
 117 {
 118         init_MUTEX(&pmu_sem);
 119
 120         if (spec->init() < 0)
 121                 return -ENODEV;
 122
 123         pmu_model = spec;
 124         init_driverfs();
 125         *ops = &pmu_ops;
 126         pmu_ops.cpu_type = pmu_model->name;
 127         printk(KERN_INFO "oprofile: using %s PMU\n", spec->name);
 128         return 0;
 129 }
 130
 131 void pmu_exit(void)
 132 {
 133         if (pmu_model) {
 134                 exit_driverfs();
 135                 pmu_model = NULL;
 136         }
 137 }
 138