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OpenCloudOS-Kernel/arch/arm64/kernel/perf_event.c

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/*
* PMU support
*
* Copyright (C) 2012 ARM Limited
* Author: Will Deacon <will.deacon@arm.com>
*
* This code is based heavily on the ARMv7 perf event code.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#define pr_fmt(fmt) "hw perfevents: " fmt
#include <linux/bitmap.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <asm/cputype.h>
#include <asm/irq.h>
#include <asm/irq_regs.h>
#include <asm/pmu.h>
#include <asm/stacktrace.h>
/*
* ARMv8 supports a maximum of 32 events.
* The cycle counter is included in this total.
*/
#define ARMPMU_MAX_HWEVENTS 32
static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events);
static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask);
static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
/* Set at runtime when we know what CPU type we are. */
static struct arm_pmu *cpu_pmu;
int
armpmu_get_max_events(void)
{
int max_events = 0;
if (cpu_pmu != NULL)
max_events = cpu_pmu->num_events;
return max_events;
}
EXPORT_SYMBOL_GPL(armpmu_get_max_events);
int perf_num_counters(void)
{
return armpmu_get_max_events();
}
EXPORT_SYMBOL_GPL(perf_num_counters);
#define HW_OP_UNSUPPORTED 0xFFFF
#define C(_x) \
PERF_COUNT_HW_CACHE_##_x
#define CACHE_OP_UNSUPPORTED 0xFFFF
static int
armpmu_map_cache_event(const unsigned (*cache_map)
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX],
u64 config)
{
unsigned int cache_type, cache_op, cache_result, ret;
cache_type = (config >> 0) & 0xff;
if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
return -EINVAL;
cache_op = (config >> 8) & 0xff;
if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
return -EINVAL;
cache_result = (config >> 16) & 0xff;
if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
return -EINVAL;
ret = (int)(*cache_map)[cache_type][cache_op][cache_result];
if (ret == CACHE_OP_UNSUPPORTED)
return -ENOENT;
return ret;
}
static int
armpmu_map_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
{
int mapping = (*event_map)[config];
return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
}
static int
armpmu_map_raw_event(u32 raw_event_mask, u64 config)
{
return (int)(config & raw_event_mask);
}
static int map_cpu_event(struct perf_event *event,
const unsigned (*event_map)[PERF_COUNT_HW_MAX],
const unsigned (*cache_map)
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX],
u32 raw_event_mask)
{
u64 config = event->attr.config;
switch (event->attr.type) {
case PERF_TYPE_HARDWARE:
return armpmu_map_event(event_map, config);
case PERF_TYPE_HW_CACHE:
return armpmu_map_cache_event(cache_map, config);
case PERF_TYPE_RAW:
return armpmu_map_raw_event(raw_event_mask, config);
}
return -ENOENT;
}
int
armpmu_event_set_period(struct perf_event *event,
struct hw_perf_event *hwc,
int idx)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
s64 left = local64_read(&hwc->period_left);
s64 period = hwc->sample_period;
int ret = 0;
if (unlikely(left <= -period)) {
left = period;
local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (unlikely(left <= 0)) {
left += period;
local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (left > (s64)armpmu->max_period)
left = armpmu->max_period;
local64_set(&hwc->prev_count, (u64)-left);
armpmu->write_counter(idx, (u64)(-left) & 0xffffffff);
perf_event_update_userpage(event);
return ret;
}
u64
armpmu_event_update(struct perf_event *event,
struct hw_perf_event *hwc,
int idx)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
u64 delta, prev_raw_count, new_raw_count;
again:
prev_raw_count = local64_read(&hwc->prev_count);
new_raw_count = armpmu->read_counter(idx);
if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count)
goto again;
delta = (new_raw_count - prev_raw_count) & armpmu->max_period;
local64_add(delta, &event->count);
local64_sub(delta, &hwc->period_left);
return new_raw_count;
}
static void
armpmu_read(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
/* Don't read disabled counters! */
if (hwc->idx < 0)
return;
armpmu_event_update(event, hwc, hwc->idx);
}
static void
armpmu_stop(struct perf_event *event, int flags)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
/*
* ARM pmu always has to update the counter, so ignore
* PERF_EF_UPDATE, see comments in armpmu_start().
*/
if (!(hwc->state & PERF_HES_STOPPED)) {
armpmu->disable(hwc, hwc->idx);
barrier(); /* why? */
armpmu_event_update(event, hwc, hwc->idx);
hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
}
}
static void
armpmu_start(struct perf_event *event, int flags)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
/*
* ARM pmu always has to reprogram the period, so ignore
* PERF_EF_RELOAD, see the comment below.
*/
if (flags & PERF_EF_RELOAD)
WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
hwc->state = 0;
/*
* Set the period again. Some counters can't be stopped, so when we
* were stopped we simply disabled the IRQ source and the counter
* may have been left counting. If we don't do this step then we may
* get an interrupt too soon or *way* too late if the overflow has
* happened since disabling.
*/
armpmu_event_set_period(event, hwc, hwc->idx);
armpmu->enable(hwc, hwc->idx);
}
static void
armpmu_del(struct perf_event *event, int flags)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct pmu_hw_events *hw_events = armpmu->get_hw_events();
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
WARN_ON(idx < 0);
armpmu_stop(event, PERF_EF_UPDATE);
hw_events->events[idx] = NULL;
clear_bit(idx, hw_events->used_mask);
perf_event_update_userpage(event);
}
static int
armpmu_add(struct perf_event *event, int flags)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct pmu_hw_events *hw_events = armpmu->get_hw_events();
struct hw_perf_event *hwc = &event->hw;
int idx;
int err = 0;
perf_pmu_disable(event->pmu);
/* If we don't have a space for the counter then finish early. */
idx = armpmu->get_event_idx(hw_events, hwc);
if (idx < 0) {
err = idx;
goto out;
}
/*
* If there is an event in the counter we are going to use then make
* sure it is disabled.
*/
event->hw.idx = idx;
armpmu->disable(hwc, idx);
hw_events->events[idx] = event;
hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
if (flags & PERF_EF_START)
armpmu_start(event, PERF_EF_RELOAD);
/* Propagate our changes to the userspace mapping. */
perf_event_update_userpage(event);
out:
perf_pmu_enable(event->pmu);
return err;
}
static int
validate_event(struct pmu_hw_events *hw_events,
struct perf_event *event)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event fake_event = event->hw;
struct pmu *leader_pmu = event->group_leader->pmu;
if (event->pmu != leader_pmu || event->state <= PERF_EVENT_STATE_OFF)
return 1;
return armpmu->get_event_idx(hw_events, &fake_event) >= 0;
}
static int
validate_group(struct perf_event *event)
{
struct perf_event *sibling, *leader = event->group_leader;
struct pmu_hw_events fake_pmu;
DECLARE_BITMAP(fake_used_mask, ARMPMU_MAX_HWEVENTS);
/*
* Initialise the fake PMU. We only need to populate the
* used_mask for the purposes of validation.
*/
memset(fake_used_mask, 0, sizeof(fake_used_mask));
fake_pmu.used_mask = fake_used_mask;
if (!validate_event(&fake_pmu, leader))
return -EINVAL;
list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
if (!validate_event(&fake_pmu, sibling))
return -EINVAL;
}
if (!validate_event(&fake_pmu, event))
return -EINVAL;
return 0;
}
static void
armpmu_release_hardware(struct arm_pmu *armpmu)
{
int i, irq, irqs;
struct platform_device *pmu_device = armpmu->plat_device;
irqs = min(pmu_device->num_resources, num_possible_cpus());
for (i = 0; i < irqs; ++i) {
if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs))
continue;
irq = platform_get_irq(pmu_device, i);
if (irq >= 0)
free_irq(irq, armpmu);
}
}
static int
armpmu_reserve_hardware(struct arm_pmu *armpmu)
{
int i, err, irq, irqs;
struct platform_device *pmu_device = armpmu->plat_device;
if (!pmu_device) {
pr_err("no PMU device registered\n");
return -ENODEV;
}
irqs = min(pmu_device->num_resources, num_possible_cpus());
if (irqs < 1) {
pr_err("no irqs for PMUs defined\n");
return -ENODEV;
}
for (i = 0; i < irqs; ++i) {
err = 0;
irq = platform_get_irq(pmu_device, i);
if (irq < 0)
continue;
/*
* If we have a single PMU interrupt that we can't shift,
* assume that we're running on a uniprocessor machine and
* continue. Otherwise, continue without this interrupt.
*/
if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
irq, i);
continue;
}
err = request_irq(irq, armpmu->handle_irq,
IRQF_NOBALANCING,
"arm-pmu", armpmu);
if (err) {
pr_err("unable to request IRQ%d for ARM PMU counters\n",
irq);
armpmu_release_hardware(armpmu);
return err;
}
cpumask_set_cpu(i, &armpmu->active_irqs);
}
return 0;
}
static void
hw_perf_event_destroy(struct perf_event *event)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
atomic_t *active_events = &armpmu->active_events;
struct mutex *pmu_reserve_mutex = &armpmu->reserve_mutex;
if (atomic_dec_and_mutex_lock(active_events, pmu_reserve_mutex)) {
armpmu_release_hardware(armpmu);
mutex_unlock(pmu_reserve_mutex);
}
}
static int
event_requires_mode_exclusion(struct perf_event_attr *attr)
{
return attr->exclude_idle || attr->exclude_user ||
attr->exclude_kernel || attr->exclude_hv;
}
static int
__hw_perf_event_init(struct perf_event *event)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int mapping, err;
mapping = armpmu->map_event(event);
if (mapping < 0) {
pr_debug("event %x:%llx not supported\n", event->attr.type,
event->attr.config);
return mapping;
}
/*
* We don't assign an index until we actually place the event onto
* hardware. Use -1 to signify that we haven't decided where to put it
* yet. For SMP systems, each core has it's own PMU so we can't do any
* clever allocation or constraints checking at this point.
*/
hwc->idx = -1;
hwc->config_base = 0;
hwc->config = 0;
hwc->event_base = 0;
/*
* Check whether we need to exclude the counter from certain modes.
*/
if ((!armpmu->set_event_filter ||
armpmu->set_event_filter(hwc, &event->attr)) &&
event_requires_mode_exclusion(&event->attr)) {
pr_debug("ARM performance counters do not support mode exclusion\n");
return -EPERM;
}
/*
* Store the event encoding into the config_base field.
*/
hwc->config_base |= (unsigned long)mapping;
if (!hwc->sample_period) {
/*
* For non-sampling runs, limit the sample_period to half
* of the counter width. That way, the new counter value
* is far less likely to overtake the previous one unless
* you have some serious IRQ latency issues.
*/
hwc->sample_period = armpmu->max_period >> 1;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
}
err = 0;
if (event->group_leader != event) {
err = validate_group(event);
if (err)
return -EINVAL;
}
return err;
}
static int armpmu_event_init(struct perf_event *event)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
int err = 0;
atomic_t *active_events = &armpmu->active_events;
if (armpmu->map_event(event) == -ENOENT)
return -ENOENT;
event->destroy = hw_perf_event_destroy;
if (!atomic_inc_not_zero(active_events)) {
mutex_lock(&armpmu->reserve_mutex);
if (atomic_read(active_events) == 0)
err = armpmu_reserve_hardware(armpmu);
if (!err)
atomic_inc(active_events);
mutex_unlock(&armpmu->reserve_mutex);
}
if (err)
return err;
err = __hw_perf_event_init(event);
if (err)
hw_perf_event_destroy(event);
return err;
}
static void armpmu_enable(struct pmu *pmu)
{
struct arm_pmu *armpmu = to_arm_pmu(pmu);
struct pmu_hw_events *hw_events = armpmu->get_hw_events();
int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
if (enabled)
armpmu->start();
}
static void armpmu_disable(struct pmu *pmu)
{
struct arm_pmu *armpmu = to_arm_pmu(pmu);
armpmu->stop();
}
static void __init armpmu_init(struct arm_pmu *armpmu)
{
atomic_set(&armpmu->active_events, 0);
mutex_init(&armpmu->reserve_mutex);
armpmu->pmu = (struct pmu) {
.pmu_enable = armpmu_enable,
.pmu_disable = armpmu_disable,
.event_init = armpmu_event_init,
.add = armpmu_add,
.del = armpmu_del,
.start = armpmu_start,
.stop = armpmu_stop,
.read = armpmu_read,
};
}
int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type)
{
armpmu_init(armpmu);
return perf_pmu_register(&armpmu->pmu, name, type);
}
/*
* ARMv8 PMUv3 Performance Events handling code.
* Common event types.
*/
enum armv8_pmuv3_perf_types {
/* Required events. */
ARMV8_PMUV3_PERFCTR_PMNC_SW_INCR = 0x00,
ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL = 0x03,
ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS = 0x04,
ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED = 0x10,
ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES = 0x11,
ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED = 0x12,
/* At least one of the following is required. */
ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED = 0x08,
ARMV8_PMUV3_PERFCTR_OP_SPEC = 0x1B,
/* Common architectural events. */
ARMV8_PMUV3_PERFCTR_MEM_READ = 0x06,
ARMV8_PMUV3_PERFCTR_MEM_WRITE = 0x07,
ARMV8_PMUV3_PERFCTR_EXC_TAKEN = 0x09,
ARMV8_PMUV3_PERFCTR_EXC_EXECUTED = 0x0A,
ARMV8_PMUV3_PERFCTR_CID_WRITE = 0x0B,
ARMV8_PMUV3_PERFCTR_PC_WRITE = 0x0C,
ARMV8_PMUV3_PERFCTR_PC_IMM_BRANCH = 0x0D,
ARMV8_PMUV3_PERFCTR_PC_PROC_RETURN = 0x0E,
ARMV8_PMUV3_PERFCTR_MEM_UNALIGNED_ACCESS = 0x0F,
ARMV8_PMUV3_PERFCTR_TTBR_WRITE = 0x1C,
/* Common microarchitectural events. */
ARMV8_PMUV3_PERFCTR_L1_ICACHE_REFILL = 0x01,
ARMV8_PMUV3_PERFCTR_ITLB_REFILL = 0x02,
ARMV8_PMUV3_PERFCTR_DTLB_REFILL = 0x05,
ARMV8_PMUV3_PERFCTR_MEM_ACCESS = 0x13,
ARMV8_PMUV3_PERFCTR_L1_ICACHE_ACCESS = 0x14,
ARMV8_PMUV3_PERFCTR_L1_DCACHE_WB = 0x15,
ARMV8_PMUV3_PERFCTR_L2_CACHE_ACCESS = 0x16,
ARMV8_PMUV3_PERFCTR_L2_CACHE_REFILL = 0x17,
ARMV8_PMUV3_PERFCTR_L2_CACHE_WB = 0x18,
ARMV8_PMUV3_PERFCTR_BUS_ACCESS = 0x19,
ARMV8_PMUV3_PERFCTR_MEM_ERROR = 0x1A,
ARMV8_PMUV3_PERFCTR_BUS_CYCLES = 0x1D,
};
/* PMUv3 HW events mapping. */
static const unsigned armv8_pmuv3_perf_map[PERF_COUNT_HW_MAX] = {
[PERF_COUNT_HW_CPU_CYCLES] = ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES,
[PERF_COUNT_HW_INSTRUCTIONS] = ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED,
[PERF_COUNT_HW_CACHE_REFERENCES] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
[PERF_COUNT_HW_CACHE_MISSES] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = HW_OP_UNSUPPORTED,
[PERF_COUNT_HW_BRANCH_MISSES] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
[PERF_COUNT_HW_BUS_CYCLES] = HW_OP_UNSUPPORTED,
[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = HW_OP_UNSUPPORTED,
[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = HW_OP_UNSUPPORTED,
};
static const unsigned armv8_pmuv3_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
[C(L1D)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
[C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
[C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(L1I)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(ITLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(BPU)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
[C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
[C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(NODE)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
};
/*
* Perf Events' indices
*/
#define ARMV8_IDX_CYCLE_COUNTER 0
#define ARMV8_IDX_COUNTER0 1
#define ARMV8_IDX_COUNTER_LAST (ARMV8_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)
#define ARMV8_MAX_COUNTERS 32
#define ARMV8_COUNTER_MASK (ARMV8_MAX_COUNTERS - 1)
/*
* ARMv8 low level PMU access
*/
/*
* Perf Event to low level counters mapping
*/
#define ARMV8_IDX_TO_COUNTER(x) \
(((x) - ARMV8_IDX_COUNTER0) & ARMV8_COUNTER_MASK)
/*
* Per-CPU PMCR: config reg
*/
#define ARMV8_PMCR_E (1 << 0) /* Enable all counters */
#define ARMV8_PMCR_P (1 << 1) /* Reset all counters */
#define ARMV8_PMCR_C (1 << 2) /* Cycle counter reset */
#define ARMV8_PMCR_D (1 << 3) /* CCNT counts every 64th cpu cycle */
#define ARMV8_PMCR_X (1 << 4) /* Export to ETM */
#define ARMV8_PMCR_DP (1 << 5) /* Disable CCNT if non-invasive debug*/
#define ARMV8_PMCR_N_SHIFT 11 /* Number of counters supported */
#define ARMV8_PMCR_N_MASK 0x1f
#define ARMV8_PMCR_MASK 0x3f /* Mask for writable bits */
/*
* PMOVSR: counters overflow flag status reg
*/
#define ARMV8_OVSR_MASK 0xffffffff /* Mask for writable bits */
#define ARMV8_OVERFLOWED_MASK ARMV8_OVSR_MASK
/*
* PMXEVTYPER: Event selection reg
*/
#define ARMV8_EVTYPE_MASK 0xc00000ff /* Mask for writable bits */
#define ARMV8_EVTYPE_EVENT 0xff /* Mask for EVENT bits */
/*
* Event filters for PMUv3
*/
#define ARMV8_EXCLUDE_EL1 (1 << 31)
#define ARMV8_EXCLUDE_EL0 (1 << 30)
#define ARMV8_INCLUDE_EL2 (1 << 27)
static inline u32 armv8pmu_pmcr_read(void)
{
u32 val;
asm volatile("mrs %0, pmcr_el0" : "=r" (val));
return val;
}
static inline void armv8pmu_pmcr_write(u32 val)
{
val &= ARMV8_PMCR_MASK;
isb();
asm volatile("msr pmcr_el0, %0" :: "r" (val));
}
static inline int armv8pmu_has_overflowed(u32 pmovsr)
{
return pmovsr & ARMV8_OVERFLOWED_MASK;
}
static inline int armv8pmu_counter_valid(int idx)
{
return idx >= ARMV8_IDX_CYCLE_COUNTER && idx <= ARMV8_IDX_COUNTER_LAST;
}
static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
{
int ret = 0;
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u checking wrong counter %d overflow status\n",
smp_processor_id(), idx);
} else {
counter = ARMV8_IDX_TO_COUNTER(idx);
ret = pmnc & BIT(counter);
}
return ret;
}
static inline int armv8pmu_select_counter(int idx)
{
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u selecting wrong PMNC counter %d\n",
smp_processor_id(), idx);
return -EINVAL;
}
counter = ARMV8_IDX_TO_COUNTER(idx);
asm volatile("msr pmselr_el0, %0" :: "r" (counter));
isb();
return idx;
}
static inline u32 armv8pmu_read_counter(int idx)
{
u32 value = 0;
if (!armv8pmu_counter_valid(idx))
pr_err("CPU%u reading wrong counter %d\n",
smp_processor_id(), idx);
else if (idx == ARMV8_IDX_CYCLE_COUNTER)
asm volatile("mrs %0, pmccntr_el0" : "=r" (value));
else if (armv8pmu_select_counter(idx) == idx)
asm volatile("mrs %0, pmxevcntr_el0" : "=r" (value));
return value;
}
static inline void armv8pmu_write_counter(int idx, u32 value)
{
if (!armv8pmu_counter_valid(idx))
pr_err("CPU%u writing wrong counter %d\n",
smp_processor_id(), idx);
else if (idx == ARMV8_IDX_CYCLE_COUNTER)
asm volatile("msr pmccntr_el0, %0" :: "r" (value));
else if (armv8pmu_select_counter(idx) == idx)
asm volatile("msr pmxevcntr_el0, %0" :: "r" (value));
}
static inline void armv8pmu_write_evtype(int idx, u32 val)
{
if (armv8pmu_select_counter(idx) == idx) {
val &= ARMV8_EVTYPE_MASK;
asm volatile("msr pmxevtyper_el0, %0" :: "r" (val));
}
}
static inline int armv8pmu_enable_counter(int idx)
{
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u enabling wrong PMNC counter %d\n",
smp_processor_id(), idx);
return -EINVAL;
}
counter = ARMV8_IDX_TO_COUNTER(idx);
asm volatile("msr pmcntenset_el0, %0" :: "r" (BIT(counter)));
return idx;
}
static inline int armv8pmu_disable_counter(int idx)
{
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u disabling wrong PMNC counter %d\n",
smp_processor_id(), idx);
return -EINVAL;
}
counter = ARMV8_IDX_TO_COUNTER(idx);
asm volatile("msr pmcntenclr_el0, %0" :: "r" (BIT(counter)));
return idx;
}
static inline int armv8pmu_enable_intens(int idx)
{
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
smp_processor_id(), idx);
return -EINVAL;
}
counter = ARMV8_IDX_TO_COUNTER(idx);
asm volatile("msr pmintenset_el1, %0" :: "r" (BIT(counter)));
return idx;
}
static inline int armv8pmu_disable_intens(int idx)
{
u32 counter;
if (!armv8pmu_counter_valid(idx)) {
pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
smp_processor_id(), idx);
return -EINVAL;
}
counter = ARMV8_IDX_TO_COUNTER(idx);
asm volatile("msr pmintenclr_el1, %0" :: "r" (BIT(counter)));
isb();
/* Clear the overflow flag in case an interrupt is pending. */
asm volatile("msr pmovsclr_el0, %0" :: "r" (BIT(counter)));
isb();
return idx;
}
static inline u32 armv8pmu_getreset_flags(void)
{
u32 value;
/* Read */
asm volatile("mrs %0, pmovsclr_el0" : "=r" (value));
/* Write to clear flags */
value &= ARMV8_OVSR_MASK;
asm volatile("msr pmovsclr_el0, %0" :: "r" (value));
return value;
}
static void armv8pmu_enable_event(struct hw_perf_event *hwc, int idx)
{
unsigned long flags;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
/*
* Enable counter and interrupt, and set the counter to count
* the event that we're interested in.
*/
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/*
* Disable counter
*/
armv8pmu_disable_counter(idx);
/*
* Set event (if destined for PMNx counters).
*/
armv8pmu_write_evtype(idx, hwc->config_base);
/*
* Enable interrupt for this counter
*/
armv8pmu_enable_intens(idx);
/*
* Enable counter
*/
armv8pmu_enable_counter(idx);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static void armv8pmu_disable_event(struct hw_perf_event *hwc, int idx)
{
unsigned long flags;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
/*
* Disable counter and interrupt
*/
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/*
* Disable counter
*/
armv8pmu_disable_counter(idx);
/*
* Disable interrupt for this counter
*/
armv8pmu_disable_intens(idx);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
{
u32 pmovsr;
struct perf_sample_data data;
struct pmu_hw_events *cpuc;
struct pt_regs *regs;
int idx;
/*
* Get and reset the IRQ flags
*/
pmovsr = armv8pmu_getreset_flags();
/*
* Did an overflow occur?
*/
if (!armv8pmu_has_overflowed(pmovsr))
return IRQ_NONE;
/*
* Handle the counter(s) overflow(s)
*/
regs = get_irq_regs();
cpuc = &__get_cpu_var(cpu_hw_events);
for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
/* Ignore if we don't have an event. */
if (!event)
continue;
/*
* We have a single interrupt for all counters. Check that
* each counter has overflowed before we process it.
*/
if (!armv8pmu_counter_has_overflowed(pmovsr, idx))
continue;
hwc = &event->hw;
armpmu_event_update(event, hwc, idx);
perf_sample_data_init(&data, 0, hwc->last_period);
if (!armpmu_event_set_period(event, hwc, idx))
continue;
if (perf_event_overflow(event, &data, regs))
cpu_pmu->disable(hwc, idx);
}
/*
* Handle the pending perf events.
*
* Note: this call *must* be run with interrupts disabled. For
* platforms that can have the PMU interrupts raised as an NMI, this
* will not work.
*/
irq_work_run();
return IRQ_HANDLED;
}
static void armv8pmu_start(void)
{
unsigned long flags;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/* Enable all counters */
armv8pmu_pmcr_write(armv8pmu_pmcr_read() | ARMV8_PMCR_E);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static void armv8pmu_stop(void)
{
unsigned long flags;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/* Disable all counters */
armv8pmu_pmcr_write(armv8pmu_pmcr_read() & ~ARMV8_PMCR_E);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc,
struct hw_perf_event *event)
{
int idx;
unsigned long evtype = event->config_base & ARMV8_EVTYPE_EVENT;
/* Always place a cycle counter into the cycle counter. */
if (evtype == ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES) {
if (test_and_set_bit(ARMV8_IDX_CYCLE_COUNTER, cpuc->used_mask))
return -EAGAIN;
return ARMV8_IDX_CYCLE_COUNTER;
}
/*
* For anything other than a cycle counter, try and use
* the events counters
*/
for (idx = ARMV8_IDX_COUNTER0; idx < cpu_pmu->num_events; ++idx) {
if (!test_and_set_bit(idx, cpuc->used_mask))
return idx;
}
/* The counters are all in use. */
return -EAGAIN;
}
/*
* Add an event filter to a given event. This will only work for PMUv2 PMUs.
*/
static int armv8pmu_set_event_filter(struct hw_perf_event *event,
struct perf_event_attr *attr)
{
unsigned long config_base = 0;
if (attr->exclude_idle)
return -EPERM;
if (attr->exclude_user)
config_base |= ARMV8_EXCLUDE_EL0;
if (attr->exclude_kernel)
config_base |= ARMV8_EXCLUDE_EL1;
if (!attr->exclude_hv)
config_base |= ARMV8_INCLUDE_EL2;
/*
* Install the filter into config_base as this is used to
* construct the event type.
*/
event->config_base = config_base;
return 0;
}
static void armv8pmu_reset(void *info)
{
u32 idx, nb_cnt = cpu_pmu->num_events;
/* The counter and interrupt enable registers are unknown at reset. */
for (idx = ARMV8_IDX_CYCLE_COUNTER; idx < nb_cnt; ++idx)
armv8pmu_disable_event(NULL, idx);
/* Initialize & Reset PMNC: C and P bits. */
armv8pmu_pmcr_write(ARMV8_PMCR_P | ARMV8_PMCR_C);
/* Disable access from userspace. */
asm volatile("msr pmuserenr_el0, %0" :: "r" (0));
}
static int armv8_pmuv3_map_event(struct perf_event *event)
{
return map_cpu_event(event, &armv8_pmuv3_perf_map,
&armv8_pmuv3_perf_cache_map, 0xFF);
}
static struct arm_pmu armv8pmu = {
.handle_irq = armv8pmu_handle_irq,
.enable = armv8pmu_enable_event,
.disable = armv8pmu_disable_event,
.read_counter = armv8pmu_read_counter,
.write_counter = armv8pmu_write_counter,
.get_event_idx = armv8pmu_get_event_idx,
.start = armv8pmu_start,
.stop = armv8pmu_stop,
.reset = armv8pmu_reset,
.max_period = (1LLU << 32) - 1,
};
static u32 __init armv8pmu_read_num_pmnc_events(void)
{
u32 nb_cnt;
/* Read the nb of CNTx counters supported from PMNC */
nb_cnt = (armv8pmu_pmcr_read() >> ARMV8_PMCR_N_SHIFT) & ARMV8_PMCR_N_MASK;
/* Add the CPU cycles counter and return */
return nb_cnt + 1;
}
static struct arm_pmu *__init armv8_pmuv3_pmu_init(void)
{
armv8pmu.name = "arm/armv8-pmuv3";
armv8pmu.map_event = armv8_pmuv3_map_event;
armv8pmu.num_events = armv8pmu_read_num_pmnc_events();
armv8pmu.set_event_filter = armv8pmu_set_event_filter;
return &armv8pmu;
}
/*
* Ensure the PMU has sane values out of reset.
* This requires SMP to be available, so exists as a separate initcall.
*/
static int __init
cpu_pmu_reset(void)
{
if (cpu_pmu && cpu_pmu->reset)
return on_each_cpu(cpu_pmu->reset, NULL, 1);
return 0;
}
arch_initcall(cpu_pmu_reset);
/*
* PMU platform driver and devicetree bindings.
*/
static struct of_device_id armpmu_of_device_ids[] = {
{.compatible = "arm,armv8-pmuv3"},
{},
};
static int armpmu_device_probe(struct platform_device *pdev)
{
if (!cpu_pmu)
return -ENODEV;
cpu_pmu->plat_device = pdev;
return 0;
}
static struct platform_driver armpmu_driver = {
.driver = {
.name = "arm-pmu",
.of_match_table = armpmu_of_device_ids,
},
.probe = armpmu_device_probe,
};
static int __init register_pmu_driver(void)
{
return platform_driver_register(&armpmu_driver);
}
device_initcall(register_pmu_driver);
static struct pmu_hw_events *armpmu_get_cpu_events(void)
{
return &__get_cpu_var(cpu_hw_events);
}
static void __init cpu_pmu_init(struct arm_pmu *armpmu)
{
int cpu;
for_each_possible_cpu(cpu) {
struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu);
events->events = per_cpu(hw_events, cpu);
events->used_mask = per_cpu(used_mask, cpu);
raw_spin_lock_init(&events->pmu_lock);
}
armpmu->get_hw_events = armpmu_get_cpu_events;
}
static int __init init_hw_perf_events(void)
{
u64 dfr = read_cpuid(ID_AA64DFR0_EL1);
switch ((dfr >> 8) & 0xf) {
case 0x1: /* PMUv3 */
cpu_pmu = armv8_pmuv3_pmu_init();
break;
}
if (cpu_pmu) {
pr_info("enabled with %s PMU driver, %d counters available\n",
cpu_pmu->name, cpu_pmu->num_events);
cpu_pmu_init(cpu_pmu);
armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
} else {
pr_info("no hardware support available\n");
}
return 0;
}
early_initcall(init_hw_perf_events);
/*
* Callchain handling code.
*/
struct frame_tail {
struct frame_tail __user *fp;
unsigned long lr;
} __attribute__((packed));
/*
* Get the return address for a single stackframe and return a pointer to the
* next frame tail.
*/
static struct frame_tail __user *
user_backtrace(struct frame_tail __user *tail,
struct perf_callchain_entry *entry)
{
struct frame_tail buftail;
unsigned long err;
/* Also check accessibility of one struct frame_tail beyond */
if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
return NULL;
pagefault_disable();
err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
pagefault_enable();
if (err)
return NULL;
perf_callchain_store(entry, buftail.lr);
/*
* Frame pointers should strictly progress back up the stack
* (towards higher addresses).
*/
if (tail >= buftail.fp)
return NULL;
return buftail.fp;
}
void perf_callchain_user(struct perf_callchain_entry *entry,
struct pt_regs *regs)
{
struct frame_tail __user *tail;
if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
/* We don't support guest os callchain now */
return;
}
tail = (struct frame_tail __user *)regs->regs[29];
while (entry->nr < PERF_MAX_STACK_DEPTH &&
tail && !((unsigned long)tail & 0xf))
tail = user_backtrace(tail, entry);
}
/*
* Gets called by walk_stackframe() for every stackframe. This will be called
* whist unwinding the stackframe and is like a subroutine return so we use
* the PC.
*/
static int callchain_trace(struct stackframe *frame, void *data)
{
struct perf_callchain_entry *entry = data;
perf_callchain_store(entry, frame->pc);
return 0;
}
void perf_callchain_kernel(struct perf_callchain_entry *entry,
struct pt_regs *regs)
{
struct stackframe frame;
if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
/* We don't support guest os callchain now */
return;
}
frame.fp = regs->regs[29];
frame.sp = regs->sp;
frame.pc = regs->pc;
walk_stackframe(&frame, callchain_trace, entry);
}
unsigned long perf_instruction_pointer(struct pt_regs *regs)
{
if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
return perf_guest_cbs->get_guest_ip();
return instruction_pointer(regs);
}
unsigned long perf_misc_flags(struct pt_regs *regs)
{
int misc = 0;
if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
if (perf_guest_cbs->is_user_mode())
misc |= PERF_RECORD_MISC_GUEST_USER;
else
misc |= PERF_RECORD_MISC_GUEST_KERNEL;
} else {
if (user_mode(regs))
misc |= PERF_RECORD_MISC_USER;
else
misc |= PERF_RECORD_MISC_KERNEL;
}
return misc;
}
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