/*
* @file op_model_ppro.h
* Family 6 perfmon and architectural perfmon MSR operations
*
* @remark Copyright 2002 OProfile authors
* @remark Copyright 2008 Intel Corporation
* @remark Read the file COPYING
*
* @author John Levon
* @author Philippe Elie
* @author Graydon Hoare
* @author Andi Kleen
*/
#include <linux/oprofile.h>
#include <linux/slab.h>
#include <asm/ptrace.h>
#include <asm/msr.h>
#include <asm/apic.h>
#include <asm/nmi.h>
#include <asm/intel_arch_perfmon.h>
#include "op_x86_model.h"
#include "op_counter.h"
static int num_counters = 2;
static int counter_width = 32;
#define CTR_IS_RESERVED(msrs, c) (msrs->counters[(c)].addr ? 1 : 0)
#define CTR_OVERFLOWED(n) (!((n) & (1ULL<<(counter_width-1))))
#define CTRL_IS_RESERVED(msrs, c) (msrs->controls[(c)].addr ? 1 : 0)
#define CTRL_READ(l, h, msrs, c) do {rdmsr((msrs->controls[(c)].addr), (l), (h)); } while (0)
#define CTRL_WRITE(l, h, msrs, c) do {wrmsr((msrs->controls[(c)].addr), (l), (h)); } while (0)
#define CTRL_SET_ACTIVE(n) (n |= (1<<22))
#define CTRL_SET_INACTIVE(n) (n &= ~(1<<22))
#define CTRL_CLEAR(x) (x &= (1<<21))
#define CTRL_SET_ENABLE(val) (val |= 1<<20)
#define CTRL_SET_USR(val, u) (val |= ((u & 1) << 16))
#define CTRL_SET_KERN(val, k) (val |= ((k & 1) << 17))
#define CTRL_SET_UM(val, m) (val |= (m << 8))
#define CTRL_SET_EVENT(val, e) (val |= e)
static u64 *reset_value;
static void ppro_fill_in_addresses(struct op_msrs * const msrs)
{
int i;
for (i = 0; i < num_counters; i++) {
if (reserve_perfctr_nmi(MSR_P6_PERFCTR0 + i))
msrs->counters[i].addr = MSR_P6_PERFCTR0 + i;
else
msrs->counters[i].addr = 0;
}
for (i = 0; i < num_counters; i++) {
if (reserve_evntsel_nmi(MSR_P6_EVNTSEL0 + i))
msrs->controls[i].addr = MSR_P6_EVNTSEL0 + i;
else
msrs->controls[i].addr = 0;
}
}
static void ppro_setup_ctrs(struct op_msrs const * const msrs)
{
unsigned int low, high;
int i;
if (!reset_value) {
reset_value = kmalloc(sizeof(reset_value[0]) * num_counters,
GFP_ATOMIC);
if (!reset_value)
return;
}
if (cpu_has_arch_perfmon) {
union cpuid10_eax eax;
eax.full = cpuid_eax(0xa);
if (counter_width < eax.split.bit_width)
counter_width = eax.split.bit_width;
}
/* clear all counters */
for (i = 0 ; i < num_counters; ++i) {
if (unlikely(!CTRL_IS_RESERVED(msrs, i)))
continue;
CTRL_READ(low, high, msrs, i);
CTRL_CLEAR(low);
CTRL_WRITE(low, high, msrs, i);
}
/* avoid a false detection of ctr overflows in NMI handler */
for (i = 0; i < num_counters; ++i) {
if (unlikely(!CTR_IS_RESERVED(msrs, i)))
continue;
wrmsrl(msrs->counters[i].addr, -1LL);
}
/* enable active counters */
for (i = 0; i < num_counters; ++i) {
if ((counter_config[i].enabled) && (CTR_IS_RESERVED(msrs, i))) {
reset_value[i] = counter_config[i].count;
wrmsrl(msrs->counters[i].addr, -reset_value[i]);
CTRL_READ(low, high, msrs, i);
CTRL_CLEAR(low);
CTRL_SET_ENABLE(low);
CTRL_SET_USR(low, counter_config[i].user);
CTRL_SET_KERN(low, counter_config[i].kernel);
CTRL_SET_UM(low, counter_config[i].unit_mask);
CTRL_SET_EVENT(low, counter_config[i].event);
CTRL_WRITE(low, high, msrs, i);
} else {
reset_value[i] = 0;
}
}
}
static int ppro_check_ctrs(struct pt_regs * const regs,
struct op_msrs const * const msrs)
{
u64 val;
int i;
for (i = 0 ; i < num_counters; ++i) {
if (!reset_value[i])
continue;
rdmsrl(msrs->counters[i].addr, val);
if (CTR_OVERFLOWED(val)) {
oprofile_add_sample(regs, i);
wrmsrl(msrs->counters[i].addr, -reset_value[i]);
}
}
/* Only P6 based Pentium M need to re-unmask the apic vector but it
* doesn't hurt other P6 variant */
apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED);
/* We can't work out if we really handled an interrupt. We
* might have caught a *second* counter just after overflowing
* the interrupt for this counter then arrives
* and we don't find a counter that's overflowed, so we
* would return 0 and get dazed + confused. Instead we always
* assume we found an overflow. This sucks.
*/
return 1;
}
static void ppro_start(struct op_msrs const * const msrs)
{
unsigned int low, high;
int i;
for (i = 0; i < num_counters; ++i) {
if (reset_value[i]) {
CTRL_READ(low, high, msrs, i);
CTRL_SET_ACTIVE(low);
CTRL_WRITE(low, high, msrs, i);
}
}
}
static void ppro_stop(struct op_msrs const * const msrs)
{
unsigned int low, high;
int i;
for (i = 0; i < num_counters; ++i) {
if (!reset_value[i])
continue;
CTRL_READ(low, high, msrs, i);
CTRL_SET_INACTIVE(low);
CTRL_WRITE(low, high, msrs, i);
}
}
static void ppro_shutdown(struct op_msrs const * const msrs)
{
int i;
for (i = 0 ; i < num_counters ; ++i) {
if (CTR_IS_RESERVED(msrs, i))
release_perfctr_nmi(MSR_P6_PERFCTR0 + i);
}
for (i = 0 ; i < num_counters ; ++i) {
if (CTRL_IS_RESERVED(msrs, i))
release_evntsel_nmi(MSR_P6_EVNTSEL0 + i);
}
if (reset_value) {
kfree(reset_value);
reset_value = NULL;
}
}
struct op_x86_model_spec op_ppro_spec = {
.num_counters = 2, /* can be overriden */
.num_controls = 2, /* dito */
.fill_in_addresses = &ppro_fill_in_addresses,
.setup_ctrs = &ppro_setup_ctrs,
.check_ctrs = &ppro_check_ctrs,
.start = &ppro_start,
.stop = &ppro_stop,
.shutdown = &ppro_shutdown
};
/*
* Architectural performance monitoring.
*
* Newer Intel CPUs (Core1+) have support for architectural
* events described in CPUID 0xA. See the IA32 SDM Vol3b.18 for details.
* The advantage of this is that it can be done without knowing about
* the specific CPU.
*/
void arch_perfmon_setup_counters(void)
{
union cpuid10_eax eax;
eax.full = cpuid_eax(0xa);
/* Workaround for BIOS bugs in 6/15. Taken from perfmon2 */
if (eax.split.version_id == 0 && current_cpu_data.x86 == 6 &&
current_cpu_data.x86_model == 15) {
eax.split.version_id = 2;
eax.split.num_counters = 2;
eax.split.bit_width = 40;
}
num_counters = eax.split.num_counters;
op_arch_perfmon_spec.num_counters = num_counters;
op_arch_perfmon_spec.num_controls = num_counters;
op_ppro_spec.num_counters = num_counters;
op_ppro_spec.num_controls = num_counters;
}
struct op_x86_model_spec op_arch_perfmon_spec = {
/* num_counters/num_controls filled in at runtime */
.fill_in_addresses = &ppro_fill_in_addresses,
/* user space does the cpuid check for available events */
.setup_ctrs = &ppro_setup_ctrs,
.check_ctrs = &ppro_check_ctrs,
.start = &ppro_start,
.stop = &ppro_stop,
.shutdown = &ppro_shutdown
};
