4  * @remark Copyright 2002-2008 OProfile authors
 
   5  * @remark Read the file COPYING
 
   7  * @author John Levon <levon@movementarian.org>
 
   8  * @author Robert Richter <robert.richter@amd.com>
 
  11 #include <linux/init.h>
 
  12 #include <linux/notifier.h>
 
  13 #include <linux/smp.h>
 
  14 #include <linux/oprofile.h>
 
  15 #include <linux/sysdev.h>
 
  16 #include <linux/slab.h>
 
  17 #include <linux/moduleparam.h>
 
  18 #include <linux/kdebug.h>
 
  19 #include <linux/cpu.h>
 
  24 #include "op_counter.h"
 
  25 #include "op_x86_model.h"
 
  27 static struct op_x86_model_spec const *model;
 
  28 static DEFINE_PER_CPU(struct op_msrs, cpu_msrs);
 
  29 static DEFINE_PER_CPU(unsigned long, saved_lvtpc);
 
  31 /* 0 == registered but off, 1 == registered and on */
 
  32 static int nmi_enabled = 0;
 
  34 static int profile_exceptions_notify(struct notifier_block *self,
 
  35                                      unsigned long val, void *data)
 
  37         struct die_args *args = (struct die_args *)data;
 
  38         int ret = NOTIFY_DONE;
 
  39         int cpu = smp_processor_id();
 
  43                 if (model->check_ctrs(args->regs, &per_cpu(cpu_msrs, cpu)))
 
  52 static void nmi_cpu_save_registers(struct op_msrs *msrs)
 
  54         unsigned int const nr_ctrs = model->num_counters;
 
  55         unsigned int const nr_ctrls = model->num_controls;
 
  56         struct op_msr *counters = msrs->counters;
 
  57         struct op_msr *controls = msrs->controls;
 
  60         for (i = 0; i < nr_ctrs; ++i) {
 
  61                 if (counters[i].addr) {
 
  62                         rdmsr(counters[i].addr,
 
  63                                 counters[i].saved.low,
 
  64                                 counters[i].saved.high);
 
  68         for (i = 0; i < nr_ctrls; ++i) {
 
  69                 if (controls[i].addr) {
 
  70                         rdmsr(controls[i].addr,
 
  71                                 controls[i].saved.low,
 
  72                                 controls[i].saved.high);
 
  77 static void nmi_save_registers(void *dummy)
 
  79         int cpu = smp_processor_id();
 
  80         struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
 
  81         nmi_cpu_save_registers(msrs);
 
  84 static void free_msrs(void)
 
  87         for_each_possible_cpu(i) {
 
  88                 kfree(per_cpu(cpu_msrs, i).counters);
 
  89                 per_cpu(cpu_msrs, i).counters = NULL;
 
  90                 kfree(per_cpu(cpu_msrs, i).controls);
 
  91                 per_cpu(cpu_msrs, i).controls = NULL;
 
  95 static int allocate_msrs(void)
 
  98         size_t controls_size = sizeof(struct op_msr) * model->num_controls;
 
  99         size_t counters_size = sizeof(struct op_msr) * model->num_counters;
 
 102         for_each_possible_cpu(i) {
 
 103                 per_cpu(cpu_msrs, i).counters = kmalloc(counters_size,
 
 105                 if (!per_cpu(cpu_msrs, i).counters) {
 
 109                 per_cpu(cpu_msrs, i).controls = kmalloc(controls_size,
 
 111                 if (!per_cpu(cpu_msrs, i).controls) {
 
 123 static void nmi_cpu_setup(void *dummy)
 
 125         int cpu = smp_processor_id();
 
 126         struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
 
 127         spin_lock(&oprofilefs_lock);
 
 128         model->setup_ctrs(msrs);
 
 129         spin_unlock(&oprofilefs_lock);
 
 130         per_cpu(saved_lvtpc, cpu) = apic_read(APIC_LVTPC);
 
 131         apic_write(APIC_LVTPC, APIC_DM_NMI);
 
 134 static struct notifier_block profile_exceptions_nb = {
 
 135         .notifier_call = profile_exceptions_notify,
 
 140 static int nmi_setup(void)
 
 145         if (!allocate_msrs())
 
 148         err = register_die_notifier(&profile_exceptions_nb);
 
 154         /* We need to serialize save and setup for HT because the subset
 
 155          * of msrs are distinct for save and setup operations
 
 158         /* Assume saved/restored counters are the same on all CPUs */
 
 159         model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
 
 160         for_each_possible_cpu(cpu) {
 
 162                         memcpy(per_cpu(cpu_msrs, cpu).counters,
 
 163                                 per_cpu(cpu_msrs, 0).counters,
 
 164                                 sizeof(struct op_msr) * model->num_counters);
 
 166                         memcpy(per_cpu(cpu_msrs, cpu).controls,
 
 167                                 per_cpu(cpu_msrs, 0).controls,
 
 168                                 sizeof(struct op_msr) * model->num_controls);
 
 172         on_each_cpu(nmi_save_registers, NULL, 1);
 
 173         on_each_cpu(nmi_cpu_setup, NULL, 1);
 
 178 static void nmi_restore_registers(struct op_msrs *msrs)
 
 180         unsigned int const nr_ctrs = model->num_counters;
 
 181         unsigned int const nr_ctrls = model->num_controls;
 
 182         struct op_msr *counters = msrs->counters;
 
 183         struct op_msr *controls = msrs->controls;
 
 186         for (i = 0; i < nr_ctrls; ++i) {
 
 187                 if (controls[i].addr) {
 
 188                         wrmsr(controls[i].addr,
 
 189                                 controls[i].saved.low,
 
 190                                 controls[i].saved.high);
 
 194         for (i = 0; i < nr_ctrs; ++i) {
 
 195                 if (counters[i].addr) {
 
 196                         wrmsr(counters[i].addr,
 
 197                                 counters[i].saved.low,
 
 198                                 counters[i].saved.high);
 
 203 static void nmi_cpu_shutdown(void *dummy)
 
 206         int cpu = smp_processor_id();
 
 207         struct op_msrs *msrs = &__get_cpu_var(cpu_msrs);
 
 209         /* restoring APIC_LVTPC can trigger an apic error because the delivery
 
 210          * mode and vector nr combination can be illegal. That's by design: on
 
 211          * power on apic lvt contain a zero vector nr which are legal only for
 
 212          * NMI delivery mode. So inhibit apic err before restoring lvtpc
 
 214         v = apic_read(APIC_LVTERR);
 
 215         apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
 
 216         apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu));
 
 217         apic_write(APIC_LVTERR, v);
 
 218         nmi_restore_registers(msrs);
 
 221 static void nmi_shutdown(void)
 
 223         struct op_msrs *msrs;
 
 226         on_each_cpu(nmi_cpu_shutdown, NULL, 1);
 
 227         unregister_die_notifier(&profile_exceptions_nb);
 
 228         msrs = &get_cpu_var(cpu_msrs);
 
 229         model->shutdown(msrs);
 
 231         put_cpu_var(cpu_msrs);
 
 234 static void nmi_cpu_start(void *dummy)
 
 236         struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
 
 240 static int nmi_start(void)
 
 242         on_each_cpu(nmi_cpu_start, NULL, 1);
 
 246 static void nmi_cpu_stop(void *dummy)
 
 248         struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
 
 252 static void nmi_stop(void)
 
 254         on_each_cpu(nmi_cpu_stop, NULL, 1);
 
 257 struct op_counter_config counter_config[OP_MAX_COUNTER];
 
 259 static int nmi_create_files(struct super_block *sb, struct dentry *root)
 
 263         for (i = 0; i < model->num_counters; ++i) {
 
 267                 /* quick little hack to _not_ expose a counter if it is not
 
 268                  * available for use.  This should protect userspace app.
 
 269                  * NOTE:  assumes 1:1 mapping here (that counters are organized
 
 270                  *        sequentially in their struct assignment).
 
 272                 if (unlikely(!avail_to_resrv_perfctr_nmi_bit(i)))
 
 275                 snprintf(buf,  sizeof(buf), "%d", i);
 
 276                 dir = oprofilefs_mkdir(sb, root, buf);
 
 277                 oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
 
 278                 oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
 
 279                 oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
 
 280                 oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
 
 281                 oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
 
 282                 oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
 
 289 static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
 
 292         int cpu = (unsigned long)data;
 
 294         case CPU_DOWN_FAILED:
 
 296                 smp_call_function_single(cpu, nmi_cpu_start, NULL, 0);
 
 298         case CPU_DOWN_PREPARE:
 
 299                 smp_call_function_single(cpu, nmi_cpu_stop, NULL, 1);
 
 305 static struct notifier_block oprofile_cpu_nb = {
 
 306         .notifier_call = oprofile_cpu_notifier
 
 312 static int nmi_suspend(struct sys_device *dev, pm_message_t state)
 
 314         /* Only one CPU left, just stop that one */
 
 315         if (nmi_enabled == 1)
 
 320 static int nmi_resume(struct sys_device *dev)
 
 322         if (nmi_enabled == 1)
 
 327 static struct sysdev_class oprofile_sysclass = {
 
 329         .resume         = nmi_resume,
 
 330         .suspend        = nmi_suspend,
 
 333 static struct sys_device device_oprofile = {
 
 335         .cls    = &oprofile_sysclass,
 
 338 static int __init init_sysfs(void)
 
 342         error = sysdev_class_register(&oprofile_sysclass);
 
 344                 error = sysdev_register(&device_oprofile);
 
 348 static void exit_sysfs(void)
 
 350         sysdev_unregister(&device_oprofile);
 
 351         sysdev_class_unregister(&oprofile_sysclass);
 
 355 #define init_sysfs() do { } while (0)
 
 356 #define exit_sysfs() do { } while (0)
 
 357 #endif /* CONFIG_PM */
 
 360 module_param(p4force, int, 0);
 
 362 static int __init p4_init(char **cpu_type)
 
 364         __u8 cpu_model = boot_cpu_data.x86_model;
 
 366         if (!p4force && (cpu_model > 6 || cpu_model == 5))
 
 370         *cpu_type = "i386/p4";
 
 374         switch (smp_num_siblings) {
 
 376                 *cpu_type = "i386/p4";
 
 381                 *cpu_type = "i386/p4-ht";
 
 382                 model = &op_p4_ht2_spec;
 
 387         printk(KERN_INFO "oprofile: P4 HyperThreading detected with > 2 threads\n");
 
 388         printk(KERN_INFO "oprofile: Reverting to timer mode.\n");
 
 392 static int __init ppro_init(char **cpu_type)
 
 394         __u8 cpu_model = boot_cpu_data.x86_model;
 
 398                 *cpu_type = "i386/ppro";
 
 401                 *cpu_type = "i386/pii";
 
 404                 *cpu_type = "i386/piii";
 
 407                 *cpu_type = "i386/p6_mobile";
 
 410                 *cpu_type = "i386/p6";
 
 413                 *cpu_type = "i386/core";
 
 416                 *cpu_type = "i386/core_2";
 
 423         model = &op_ppro_spec;
 
 427 static int __init arch_perfmon_init(char **cpu_type)
 
 429         if (!cpu_has_arch_perfmon)
 
 431         *cpu_type = "i386/arch_perfmon";
 
 432         model = &op_arch_perfmon_spec;
 
 433         arch_perfmon_setup_counters();
 
 437 /* in order to get sysfs right */
 
 438 static int using_nmi;
 
 440 int __init op_nmi_init(struct oprofile_operations *ops)
 
 442         __u8 vendor = boot_cpu_data.x86_vendor;
 
 443         __u8 family = boot_cpu_data.x86;
 
 444         char *cpu_type = NULL;
 
 452                 /* Needs to be at least an Athlon (or hammer in 32bit mode) */
 
 458                         model = &op_amd_spec;
 
 459                         cpu_type = "i386/athlon";
 
 462                         model = &op_amd_spec;
 
 463                         /* Actually it could be i386/hammer too, but give
 
 464                          user space an consistent name. */
 
 465                         cpu_type = "x86-64/hammer";
 
 468                         model = &op_amd_spec;
 
 469                         cpu_type = "x86-64/family10";
 
 472                         model = &op_amd_spec;
 
 473                         cpu_type = "x86-64/family11h";
 
 478         case X86_VENDOR_INTEL:
 
 485                         /* A P6-class processor */
 
 487                         ppro_init(&cpu_type);
 
 494                 if (!cpu_type && !arch_perfmon_init(&cpu_type))
 
 503         register_cpu_notifier(&oprofile_cpu_nb);
 
 505         /* default values, can be overwritten by model */
 
 506         ops->create_files = nmi_create_files;
 
 507         ops->setup = nmi_setup;
 
 508         ops->shutdown = nmi_shutdown;
 
 509         ops->start = nmi_start;
 
 510         ops->stop = nmi_stop;
 
 511         ops->cpu_type = cpu_type;
 
 514                 ret = model->init(ops);
 
 520         printk(KERN_INFO "oprofile: using NMI interrupt.\n");
 
 524 void op_nmi_exit(void)
 
 529                 unregister_cpu_notifier(&oprofile_cpu_nb);