swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Tip revision: 0e81a8ae37687845f7cdfa2adce14ea6a5f1dd34 authored by Linus Torvalds on 01 April 2008, 19:44:26 UTC
Linux 2.6.25-rc8
Linux 2.6.25-rc8
Tip revision: 0e81a8a
op_model_ppro.c
/**
* @file op_model_ppro.h
* pentium pro / P6 model-specific MSR operations
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon
* @author Philippe Elie
* @author Graydon Hoare
*/
#include <linux/oprofile.h>
#include <asm/ptrace.h>
#include <asm/msr.h>
#include <asm/apic.h>
#include <asm/nmi.h>
#include "op_x86_model.h"
#include "op_counter.h"
#define NUM_COUNTERS 2
#define NUM_CONTROLS 2
#define CTR_IS_RESERVED(msrs,c) (msrs->counters[(c)].addr ? 1 : 0)
#define CTR_READ(l,h,msrs,c) do {rdmsr(msrs->counters[(c)].addr, (l), (h));} while (0)
#define CTR_32BIT_WRITE(l,msrs,c) \
do {wrmsr(msrs->counters[(c)].addr, -(u32)(l), 0);} while (0)
#define CTR_OVERFLOWED(n) (!((n) & (1U<<31)))
#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 unsigned long reset_value[NUM_COUNTERS];
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_CONTROLS; 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;
/* clear all counters */
for (i = 0 ; i < NUM_CONTROLS; ++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;
CTR_32BIT_WRITE(1, msrs, i);
}
/* 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;
CTR_32BIT_WRITE(counter_config[i].count, msrs, 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)
{
unsigned int low, high;
int i;
for (i = 0 ; i < NUM_COUNTERS; ++i) {
if (!reset_value[i])
continue;
CTR_READ(low, high, msrs, i);
if (CTR_OVERFLOWED(low)) {
oprofile_add_sample(regs, i);
CTR_32BIT_WRITE(reset_value[i], msrs, 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_CONTROLS ; ++i) {
if (CTRL_IS_RESERVED(msrs,i))
release_evntsel_nmi(MSR_P6_EVNTSEL0 + i);
}
}
struct op_x86_model_spec const op_ppro_spec = {
.num_counters = NUM_COUNTERS,
.num_controls = NUM_CONTROLS,
.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
};