linux/arch/x86/oprofile/nmi_int.c
Mike Travis d18d00f5db x86: oprofile: remove NR_CPUS arrays in arch/x86/oprofile/nmi_int.c
Change the following arrays sized by NR_CPUS to be PERCPU variables:

	static struct op_msrs cpu_msrs[NR_CPUS];
	static unsigned long saved_lvtpc[NR_CPUS];

Also some minor complaints from checkpatch.pl fixed.

Based on:
	git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
	git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86.git

All changes were transparent except for:

 static void nmi_shutdown(void)
 {
+	struct op_msrs *msrs = &__get_cpu_var(cpu_msrs);
 	nmi_enabled = 0;
 	on_each_cpu(nmi_cpu_shutdown, NULL, 0, 1);
 	unregister_die_notifier(&profile_exceptions_nb);
-	model->shutdown(cpu_msrs);
+	model->shutdown(msrs);
 	free_msrs();
 }

The existing code passed a reference to cpu 0's instance of struct op_msrs
to model->shutdown, whilst the other functions are passed a reference to
<this cpu's> instance of a struct op_msrs.  This seemed to be a bug to me
even though as long as cpu 0 and <this cpu> are of the same type it would
have the same effect...?

Cc: Philippe Elie <phil.el@wanadoo.fr>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19 19:44:58 +02:00

467 lines
10 KiB
C

/**
* @file nmi_int.c
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/smp.h>
#include <linux/oprofile.h>
#include <linux/sysdev.h>
#include <linux/slab.h>
#include <linux/moduleparam.h>
#include <linux/kdebug.h>
#include <asm/nmi.h>
#include <asm/msr.h>
#include <asm/apic.h>
#include "op_counter.h"
#include "op_x86_model.h"
static struct op_x86_model_spec const *model;
static DEFINE_PER_CPU(struct op_msrs, cpu_msrs);
static DEFINE_PER_CPU(unsigned long, saved_lvtpc);
static int nmi_start(void);
static void nmi_stop(void);
/* 0 == registered but off, 1 == registered and on */
static int nmi_enabled = 0;
#ifdef CONFIG_PM
static int nmi_suspend(struct sys_device *dev, pm_message_t state)
{
if (nmi_enabled == 1)
nmi_stop();
return 0;
}
static int nmi_resume(struct sys_device *dev)
{
if (nmi_enabled == 1)
nmi_start();
return 0;
}
static struct sysdev_class oprofile_sysclass = {
.name = "oprofile",
.resume = nmi_resume,
.suspend = nmi_suspend,
};
static struct sys_device device_oprofile = {
.id = 0,
.cls = &oprofile_sysclass,
};
static int __init init_sysfs(void)
{
int error;
error = sysdev_class_register(&oprofile_sysclass);
if (!error)
error = sysdev_register(&device_oprofile);
return error;
}
static void exit_sysfs(void)
{
sysdev_unregister(&device_oprofile);
sysdev_class_unregister(&oprofile_sysclass);
}
#else
#define init_sysfs() do { } while (0)
#define exit_sysfs() do { } while (0)
#endif /* CONFIG_PM */
static int profile_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
{
struct die_args *args = (struct die_args *)data;
int ret = NOTIFY_DONE;
int cpu = smp_processor_id();
switch (val) {
case DIE_NMI:
if (model->check_ctrs(args->regs, &per_cpu(cpu_msrs, cpu)))
ret = NOTIFY_STOP;
break;
default:
break;
}
return ret;
}
static void nmi_cpu_save_registers(struct op_msrs *msrs)
{
unsigned int const nr_ctrs = model->num_counters;
unsigned int const nr_ctrls = model->num_controls;
struct op_msr *counters = msrs->counters;
struct op_msr *controls = msrs->controls;
unsigned int i;
for (i = 0; i < nr_ctrs; ++i) {
if (counters[i].addr) {
rdmsr(counters[i].addr,
counters[i].saved.low,
counters[i].saved.high);
}
}
for (i = 0; i < nr_ctrls; ++i) {
if (controls[i].addr) {
rdmsr(controls[i].addr,
controls[i].saved.low,
controls[i].saved.high);
}
}
}
static void nmi_save_registers(void *dummy)
{
int cpu = smp_processor_id();
struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
nmi_cpu_save_registers(msrs);
}
static void free_msrs(void)
{
int i;
for_each_possible_cpu(i) {
kfree(per_cpu(cpu_msrs, i).counters);
per_cpu(cpu_msrs, i).counters = NULL;
kfree(per_cpu(cpu_msrs, i).controls);
per_cpu(cpu_msrs, i).controls = NULL;
}
}
static int allocate_msrs(void)
{
int success = 1;
size_t controls_size = sizeof(struct op_msr) * model->num_controls;
size_t counters_size = sizeof(struct op_msr) * model->num_counters;
int i;
for_each_possible_cpu(i) {
per_cpu(cpu_msrs, i).counters = kmalloc(counters_size,
GFP_KERNEL);
if (!per_cpu(cpu_msrs, i).counters) {
success = 0;
break;
}
per_cpu(cpu_msrs, i).controls = kmalloc(controls_size,
GFP_KERNEL);
if (!per_cpu(cpu_msrs, i).controls) {
success = 0;
break;
}
}
if (!success)
free_msrs();
return success;
}
static void nmi_cpu_setup(void *dummy)
{
int cpu = smp_processor_id();
struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
spin_lock(&oprofilefs_lock);
model->setup_ctrs(msrs);
spin_unlock(&oprofilefs_lock);
per_cpu(saved_lvtpc, cpu) = apic_read(APIC_LVTPC);
apic_write(APIC_LVTPC, APIC_DM_NMI);
}
static struct notifier_block profile_exceptions_nb = {
.notifier_call = profile_exceptions_notify,
.next = NULL,
.priority = 0
};
static int nmi_setup(void)
{
int err = 0;
int cpu;
if (!allocate_msrs())
return -ENOMEM;
err = register_die_notifier(&profile_exceptions_nb);
if (err) {
free_msrs();
return err;
}
/* We need to serialize save and setup for HT because the subset
* of msrs are distinct for save and setup operations
*/
/* Assume saved/restored counters are the same on all CPUs */
model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
for_each_possible_cpu(cpu) {
if (cpu != 0) {
memcpy(per_cpu(cpu_msrs, cpu).counters,
per_cpu(cpu_msrs, 0).counters,
sizeof(struct op_msr) * model->num_counters);
memcpy(per_cpu(cpu_msrs, cpu).controls,
per_cpu(cpu_msrs, 0).controls,
sizeof(struct op_msr) * model->num_controls);
}
}
on_each_cpu(nmi_save_registers, NULL, 0, 1);
on_each_cpu(nmi_cpu_setup, NULL, 0, 1);
nmi_enabled = 1;
return 0;
}
static void nmi_restore_registers(struct op_msrs *msrs)
{
unsigned int const nr_ctrs = model->num_counters;
unsigned int const nr_ctrls = model->num_controls;
struct op_msr *counters = msrs->counters;
struct op_msr *controls = msrs->controls;
unsigned int i;
for (i = 0; i < nr_ctrls; ++i) {
if (controls[i].addr) {
wrmsr(controls[i].addr,
controls[i].saved.low,
controls[i].saved.high);
}
}
for (i = 0; i < nr_ctrs; ++i) {
if (counters[i].addr) {
wrmsr(counters[i].addr,
counters[i].saved.low,
counters[i].saved.high);
}
}
}
static void nmi_cpu_shutdown(void *dummy)
{
unsigned int v;
int cpu = smp_processor_id();
struct op_msrs *msrs = &__get_cpu_var(cpu_msrs);
/* restoring APIC_LVTPC can trigger an apic error because the delivery
* mode and vector nr combination can be illegal. That's by design: on
* power on apic lvt contain a zero vector nr which are legal only for
* NMI delivery mode. So inhibit apic err before restoring lvtpc
*/
v = apic_read(APIC_LVTERR);
apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu));
apic_write(APIC_LVTERR, v);
nmi_restore_registers(msrs);
}
static void nmi_shutdown(void)
{
struct op_msrs *msrs = &__get_cpu_var(cpu_msrs);
nmi_enabled = 0;
on_each_cpu(nmi_cpu_shutdown, NULL, 0, 1);
unregister_die_notifier(&profile_exceptions_nb);
model->shutdown(msrs);
free_msrs();
}
static void nmi_cpu_start(void *dummy)
{
struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
model->start(msrs);
}
static int nmi_start(void)
{
on_each_cpu(nmi_cpu_start, NULL, 0, 1);
return 0;
}
static void nmi_cpu_stop(void *dummy)
{
struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
model->stop(msrs);
}
static void nmi_stop(void)
{
on_each_cpu(nmi_cpu_stop, NULL, 0, 1);
}
struct op_counter_config counter_config[OP_MAX_COUNTER];
static int nmi_create_files(struct super_block *sb, struct dentry *root)
{
unsigned int i;
for (i = 0; i < model->num_counters; ++i) {
struct dentry *dir;
char buf[4];
/* quick little hack to _not_ expose a counter if it is not
* available for use. This should protect userspace app.
* NOTE: assumes 1:1 mapping here (that counters are organized
* sequentially in their struct assignment).
*/
if (unlikely(!avail_to_resrv_perfctr_nmi_bit(i)))
continue;
snprintf(buf, sizeof(buf), "%d", i);
dir = oprofilefs_mkdir(sb, root, buf);
oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
}
return 0;
}
static int p4force;
module_param(p4force, int, 0);
static int __init p4_init(char **cpu_type)
{
__u8 cpu_model = boot_cpu_data.x86_model;
if (!p4force && (cpu_model > 6 || cpu_model == 5))
return 0;
#ifndef CONFIG_SMP
*cpu_type = "i386/p4";
model = &op_p4_spec;
return 1;
#else
switch (smp_num_siblings) {
case 1:
*cpu_type = "i386/p4";
model = &op_p4_spec;
return 1;
case 2:
*cpu_type = "i386/p4-ht";
model = &op_p4_ht2_spec;
return 1;
}
#endif
printk(KERN_INFO "oprofile: P4 HyperThreading detected with > 2 threads\n");
printk(KERN_INFO "oprofile: Reverting to timer mode.\n");
return 0;
}
static int __init ppro_init(char **cpu_type)
{
__u8 cpu_model = boot_cpu_data.x86_model;
if (cpu_model == 14)
*cpu_type = "i386/core";
else if (cpu_model == 15 || cpu_model == 23)
*cpu_type = "i386/core_2";
else if (cpu_model > 0xd)
return 0;
else if (cpu_model == 9) {
*cpu_type = "i386/p6_mobile";
} else if (cpu_model > 5) {
*cpu_type = "i386/piii";
} else if (cpu_model > 2) {
*cpu_type = "i386/pii";
} else {
*cpu_type = "i386/ppro";
}
model = &op_ppro_spec;
return 1;
}
/* in order to get sysfs right */
static int using_nmi;
int __init op_nmi_init(struct oprofile_operations *ops)
{
__u8 vendor = boot_cpu_data.x86_vendor;
__u8 family = boot_cpu_data.x86;
char *cpu_type;
if (!cpu_has_apic)
return -ENODEV;
switch (vendor) {
case X86_VENDOR_AMD:
/* Needs to be at least an Athlon (or hammer in 32bit mode) */
switch (family) {
default:
return -ENODEV;
case 6:
model = &op_athlon_spec;
cpu_type = "i386/athlon";
break;
case 0xf:
model = &op_athlon_spec;
/* Actually it could be i386/hammer too, but give
user space an consistent name. */
cpu_type = "x86-64/hammer";
break;
case 0x10:
model = &op_athlon_spec;
cpu_type = "x86-64/family10";
break;
}
break;
case X86_VENDOR_INTEL:
switch (family) {
/* Pentium IV */
case 0xf:
if (!p4_init(&cpu_type))
return -ENODEV;
break;
/* A P6-class processor */
case 6:
if (!ppro_init(&cpu_type))
return -ENODEV;
break;
default:
return -ENODEV;
}
break;
default:
return -ENODEV;
}
init_sysfs();
using_nmi = 1;
ops->create_files = nmi_create_files;
ops->setup = nmi_setup;
ops->shutdown = nmi_shutdown;
ops->start = nmi_start;
ops->stop = nmi_stop;
ops->cpu_type = cpu_type;
printk(KERN_INFO "oprofile: using NMI interrupt.\n");
return 0;
}
void op_nmi_exit(void)
{
if (using_nmi)
exit_sysfs();
}