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x86, perfcounters: prepare for fixed-mode PMCs

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Impact: refactor the x86 code for fixed-mode PMCs

Extend the data structures and rename the existing facilities
to allow for a 'generic' versus 'fixed' counter distinction.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar
2008-12-17 09:09:13 +01:00
parent 5c167b8585
commit eb2b861810
3 changed files with 38 additions and 27 deletions
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11
arch/x86/include/asm/perf_counter.h
View File

@@ -1,6 +1,13 @@
#ifndef _ASM_X86_PERF_COUNTER_H #ifndef _ASM_X86_PERF_COUNTER_H
#define _ASM_X86_PERF_COUNTER_H #define _ASM_X86_PERF_COUNTER_H
/*
* Performance counter hw details:
*/
#define X86_PMC_MAX_GENERIC 8
#define X86_PMC_MAX_FIXED 3
#define MSR_ARCH_PERFMON_PERFCTR0 0xc1 #define MSR_ARCH_PERFMON_PERFCTR0 0xc1
#define MSR_ARCH_PERFMON_PERFCTR1 0xc2 #define MSR_ARCH_PERFMON_PERFCTR1 0xc2
@@ -20,6 +27,10 @@
#define ARCH_PERFMON_BRANCH_MISSES_RETIRED 6 #define ARCH_PERFMON_BRANCH_MISSES_RETIRED 6
/*
* Intel "Architectural Performance Monitoring" CPUID
* detection/enumeration details:
*/
union cpuid10_eax { union cpuid10_eax {
struct { struct {
unsigned int version_id:8; unsigned int version_id:8;

53
arch/x86/kernel/cpu/perf_counter.c
View File

@@ -27,13 +27,12 @@ static bool perf_counters_initialized __read_mostly;
static int nr_hw_counters __read_mostly; static int nr_hw_counters __read_mostly;
static u32 perf_counter_mask __read_mostly; static u32 perf_counter_mask __read_mostly;
/* No support for fixed function counters yet */
#define MAX_HW_COUNTERS 8
struct cpu_hw_counters { struct cpu_hw_counters {
struct perf_counter *counters[MAX_HW_COUNTERS]; struct perf_counter *generic[X86_PMC_MAX_GENERIC];
unsigned long used[BITS_TO_LONGS(MAX_HW_COUNTERS)]; unsigned long used[BITS_TO_LONGS(X86_PMC_MAX_GENERIC)];
struct perf_counter *fixed[X86_PMC_MAX_FIXED];
unsigned long used_fixed[BITS_TO_LONGS(X86_PMC_MAX_FIXED)];
}; };
/* /*
@@ -185,7 +184,7 @@ void hw_perf_restore(u64 ctrl)
EXPORT_SYMBOL_GPL(hw_perf_restore); EXPORT_SYMBOL_GPL(hw_perf_restore);
static inline void static inline void
__x86_perf_counter_disable(struct perf_counter *counter, __pmc_generic_disable(struct perf_counter *counter,
struct hw_perf_counter *hwc, unsigned int idx) struct hw_perf_counter *hwc, unsigned int idx)
{ {
int err; int err;
@@ -193,7 +192,7 @@ __x86_perf_counter_disable(struct perf_counter *counter,
err = wrmsr_safe(hwc->config_base + idx, hwc->config, 0); err = wrmsr_safe(hwc->config_base + idx, hwc->config, 0);
} }
static DEFINE_PER_CPU(u64, prev_left[MAX_HW_COUNTERS]); static DEFINE_PER_CPU(u64, prev_left[X86_PMC_MAX_GENERIC]);
/* /*
* Set the next IRQ period, based on the hwc->period_left value. * Set the next IRQ period, based on the hwc->period_left value.
@@ -231,7 +230,7 @@ __hw_perf_counter_set_period(struct perf_counter *counter,
} }
static void static void
__x86_perf_counter_enable(struct perf_counter *counter, __pmc_generic_enable(struct perf_counter *counter,
struct hw_perf_counter *hwc, int idx) struct hw_perf_counter *hwc, int idx)
{ {
wrmsr(hwc->config_base + idx, wrmsr(hwc->config_base + idx,
@@ -241,7 +240,7 @@ __x86_perf_counter_enable(struct perf_counter *counter,
/* /*
* Find a PMC slot for the freshly enabled / scheduled in counter: * Find a PMC slot for the freshly enabled / scheduled in counter:
*/ */
static void x86_perf_counter_enable(struct perf_counter *counter) static void pmc_generic_enable(struct perf_counter *counter)
{ {
struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters); struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
struct hw_perf_counter *hwc = &counter->hw; struct hw_perf_counter *hwc = &counter->hw;
@@ -256,12 +255,12 @@ static void x86_perf_counter_enable(struct perf_counter *counter)
perf_counters_lapic_init(hwc->nmi); perf_counters_lapic_init(hwc->nmi);
__x86_perf_counter_disable(counter, hwc, idx); __pmc_generic_disable(counter, hwc, idx);
cpuc->counters[idx] = counter; cpuc->generic[idx] = counter;
__hw_perf_counter_set_period(counter, hwc, idx); __hw_perf_counter_set_period(counter, hwc, idx);
__x86_perf_counter_enable(counter, hwc, idx); __pmc_generic_enable(counter, hwc, idx);
} }
void perf_counter_print_debug(void) void perf_counter_print_debug(void)
@@ -301,16 +300,16 @@ void perf_counter_print_debug(void)
local_irq_enable(); local_irq_enable();
} }
static void x86_perf_counter_disable(struct perf_counter *counter) static void pmc_generic_disable(struct perf_counter *counter)
{ {
struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters); struct cpu_hw_counters *cpuc = &__get_cpu_var(cpu_hw_counters);
struct hw_perf_counter *hwc = &counter->hw; struct hw_perf_counter *hwc = &counter->hw;
unsigned int idx = hwc->idx; unsigned int idx = hwc->idx;
__x86_perf_counter_disable(counter, hwc, idx); __pmc_generic_disable(counter, hwc, idx);
clear_bit(idx, cpuc->used); clear_bit(idx, cpuc->used);
cpuc->counters[idx] = NULL; cpuc->generic[idx] = NULL;
/* /*
* Drain the remaining delta count out of a counter * Drain the remaining delta count out of a counter
@@ -349,7 +348,7 @@ static void perf_save_and_restart(struct perf_counter *counter)
__hw_perf_counter_set_period(counter, hwc, idx); __hw_perf_counter_set_period(counter, hwc, idx);
if (pmc_ctrl & ARCH_PERFMON_EVENTSEL0_ENABLE) if (pmc_ctrl & ARCH_PERFMON_EVENTSEL0_ENABLE)
__x86_perf_counter_enable(counter, hwc, idx); __pmc_generic_enable(counter, hwc, idx);
} }
static void static void
@@ -392,7 +391,7 @@ static void __smp_perf_counter_interrupt(struct pt_regs *regs, int nmi)
again: again:
ack = status; ack = status;
for_each_bit(bit, (unsigned long *) &status, nr_hw_counters) { for_each_bit(bit, (unsigned long *) &status, nr_hw_counters) {
struct perf_counter *counter = cpuc->counters[bit]; struct perf_counter *counter = cpuc->generic[bit];
clear_bit(bit, (unsigned long *) &status); clear_bit(bit, (unsigned long *) &status);
if (!counter) if (!counter)
@@ -412,7 +411,7 @@ again:
} }
/* /*
* From NMI context we cannot call into the scheduler to * From NMI context we cannot call into the scheduler to
* do a task wakeup - but we mark these counters as * do a task wakeup - but we mark these generic as
* wakeup_pending and initate a wakeup callback: * wakeup_pending and initate a wakeup callback:
*/ */
if (nmi) { if (nmi) {
@@ -462,7 +461,7 @@ void perf_counter_notify(struct pt_regs *regs)
cpuc = &per_cpu(cpu_hw_counters, cpu); cpuc = &per_cpu(cpu_hw_counters, cpu);
for_each_bit(bit, cpuc->used, nr_hw_counters) { for_each_bit(bit, cpuc->used, nr_hw_counters) {
struct perf_counter *counter = cpuc->counters[bit]; struct perf_counter *counter = cpuc->generic[bit];
if (!counter) if (!counter)
continue; continue;
@@ -539,10 +538,10 @@ void __init init_hw_perf_counters(void)
printk(KERN_INFO "... version: %d\n", eax.split.version_id); printk(KERN_INFO "... version: %d\n", eax.split.version_id);
printk(KERN_INFO "... num_counters: %d\n", eax.split.num_counters); printk(KERN_INFO "... num_counters: %d\n", eax.split.num_counters);
nr_hw_counters = eax.split.num_counters; nr_hw_counters = eax.split.num_counters;
if (nr_hw_counters > MAX_HW_COUNTERS) { if (nr_hw_counters > X86_PMC_MAX_GENERIC) {
nr_hw_counters = MAX_HW_COUNTERS; nr_hw_counters = X86_PMC_MAX_GENERIC;
WARN(1, KERN_ERR "hw perf counters %d > max(%d), clipping!", WARN(1, KERN_ERR "hw perf counters %d > max(%d), clipping!",
nr_hw_counters, MAX_HW_COUNTERS); nr_hw_counters, X86_PMC_MAX_GENERIC);
} }
perf_counter_mask = (1 << nr_hw_counters) - 1; perf_counter_mask = (1 << nr_hw_counters) - 1;
perf_max_counters = nr_hw_counters; perf_max_counters = nr_hw_counters;
@@ -556,15 +555,15 @@ void __init init_hw_perf_counters(void)
register_die_notifier(&perf_counter_nmi_notifier); register_die_notifier(&perf_counter_nmi_notifier);
} }
static void x86_perf_counter_read(struct perf_counter *counter) static void pmc_generic_read(struct perf_counter *counter)
{ {
x86_perf_counter_update(counter, &counter->hw, counter->hw.idx); x86_perf_counter_update(counter, &counter->hw, counter->hw.idx);
} }
static const struct hw_perf_counter_ops x86_perf_counter_ops = { static const struct hw_perf_counter_ops x86_perf_counter_ops = {
.hw_perf_counter_enable = x86_perf_counter_enable, .hw_perf_counter_enable = pmc_generic_enable,
.hw_perf_counter_disable = x86_perf_counter_disable, .hw_perf_counter_disable = pmc_generic_disable,
.hw_perf_counter_read = x86_perf_counter_read, .hw_perf_counter_read = pmc_generic_read,
}; };
const struct hw_perf_counter_ops * const struct hw_perf_counter_ops *

1
include/linux/perf_counter.h
View File

@@ -14,6 +14,7 @@
#define _LINUX_PERF_COUNTER_H #define _LINUX_PERF_COUNTER_H
#include <asm/atomic.h> #include <asm/atomic.h>
#include <asm/perf_counter.h>
#include <linux/list.h> #include <linux/list.h>
#include <linux/mutex.h> #include <linux/mutex.h>