diff options
Diffstat (limited to 'arch/riscv/kernel/perf_event.c')
| -rw-r--r-- | arch/riscv/kernel/perf_event.c | 485 |
1 files changed, 0 insertions, 485 deletions
diff --git a/arch/riscv/kernel/perf_event.c b/arch/riscv/kernel/perf_event.c deleted file mode 100644 index c835f0362d94..000000000000 --- a/arch/riscv/kernel/perf_event.c +++ /dev/null @@ -1,485 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> - * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar - * Copyright (C) 2009 Jaswinder Singh Rajput - * Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter - * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra - * Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com> - * Copyright (C) 2009 Google, Inc., Stephane Eranian - * Copyright 2014 Tilera Corporation. All Rights Reserved. - * Copyright (C) 2018 Andes Technology Corporation - * - * Perf_events support for RISC-V platforms. - * - * Since the spec. (as of now, Priv-Spec 1.10) does not provide enough - * functionality for perf event to fully work, this file provides - * the very basic framework only. - * - * For platform portings, please check Documentations/riscv/pmu.txt. - * - * The Copyright line includes x86 and tile ones. - */ - -#include <linux/kprobes.h> -#include <linux/kernel.h> -#include <linux/kdebug.h> -#include <linux/mutex.h> -#include <linux/bitmap.h> -#include <linux/irq.h> -#include <linux/perf_event.h> -#include <linux/atomic.h> -#include <linux/of.h> -#include <asm/perf_event.h> - -static const struct riscv_pmu *riscv_pmu __read_mostly; -static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events); - -/* - * Hardware & cache maps and their methods - */ - -static const int riscv_hw_event_map[] = { - [PERF_COUNT_HW_CPU_CYCLES] = RISCV_PMU_CYCLE, - [PERF_COUNT_HW_INSTRUCTIONS] = RISCV_PMU_INSTRET, - [PERF_COUNT_HW_CACHE_REFERENCES] = RISCV_OP_UNSUPP, - [PERF_COUNT_HW_CACHE_MISSES] = RISCV_OP_UNSUPP, - [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = RISCV_OP_UNSUPP, - [PERF_COUNT_HW_BRANCH_MISSES] = RISCV_OP_UNSUPP, - [PERF_COUNT_HW_BUS_CYCLES] = RISCV_OP_UNSUPP, -}; - -#define C(x) PERF_COUNT_HW_CACHE_##x -static const int riscv_cache_event_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)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, - [C(L1I)] = { - [C(OP_READ)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, - [C(LL)] = { - [C(OP_READ)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, - [C(DTLB)] = { - [C(OP_READ)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, - [C(ITLB)] = { - [C(OP_READ)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, - [C(BPU)] = { - [C(OP_READ)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_WRITE)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - [C(OP_PREFETCH)] = { - [C(RESULT_ACCESS)] = RISCV_OP_UNSUPP, - [C(RESULT_MISS)] = RISCV_OP_UNSUPP, - }, - }, -}; - -static int riscv_map_hw_event(u64 config) -{ - if (config >= riscv_pmu->max_events) - return -EINVAL; - - return riscv_pmu->hw_events[config]; -} - -static int riscv_map_cache_decode(u64 config, unsigned int *type, - unsigned int *op, unsigned int *result) -{ - return -ENOENT; -} - -static int riscv_map_cache_event(u64 config) -{ - unsigned int type, op, result; - int err = -ENOENT; - int code; - - err = riscv_map_cache_decode(config, &type, &op, &result); - if (!riscv_pmu->cache_events || err) - return err; - - if (type >= PERF_COUNT_HW_CACHE_MAX || - op >= PERF_COUNT_HW_CACHE_OP_MAX || - result >= PERF_COUNT_HW_CACHE_RESULT_MAX) - return -EINVAL; - - code = (*riscv_pmu->cache_events)[type][op][result]; - if (code == RISCV_OP_UNSUPP) - return -EINVAL; - - return code; -} - -/* - * Low-level functions: reading/writing counters - */ - -static inline u64 read_counter(int idx) -{ - u64 val = 0; - - switch (idx) { - case RISCV_PMU_CYCLE: - val = csr_read(CSR_CYCLE); - break; - case RISCV_PMU_INSTRET: - val = csr_read(CSR_INSTRET); - break; - default: - WARN_ON_ONCE(idx < 0 || idx > RISCV_MAX_COUNTERS); - return -EINVAL; - } - - return val; -} - -static inline void write_counter(int idx, u64 value) -{ - /* currently not supported */ - WARN_ON_ONCE(1); -} - -/* - * pmu->read: read and update the counter - * - * Other architectures' implementation often have a xxx_perf_event_update - * routine, which can return counter values when called in the IRQ, but - * return void when being called by the pmu->read method. - */ -static void riscv_pmu_read(struct perf_event *event) -{ - struct hw_perf_event *hwc = &event->hw; - u64 prev_raw_count, new_raw_count; - u64 oldval; - int idx = hwc->idx; - u64 delta; - - do { - prev_raw_count = local64_read(&hwc->prev_count); - new_raw_count = read_counter(idx); - - oldval = local64_cmpxchg(&hwc->prev_count, prev_raw_count, - new_raw_count); - } while (oldval != prev_raw_count); - - /* - * delta is the value to update the counter we maintain in the kernel. - */ - delta = (new_raw_count - prev_raw_count) & - ((1ULL << riscv_pmu->counter_width) - 1); - local64_add(delta, &event->count); - /* - * Something like local64_sub(delta, &hwc->period_left) here is - * needed if there is an interrupt for perf. - */ -} - -/* - * State transition functions: - * - * stop()/start() & add()/del() - */ - -/* - * pmu->stop: stop the counter - */ -static void riscv_pmu_stop(struct perf_event *event, int flags) -{ - struct hw_perf_event *hwc = &event->hw; - - WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED); - hwc->state |= PERF_HES_STOPPED; - - if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) { - riscv_pmu->pmu->read(event); - hwc->state |= PERF_HES_UPTODATE; - } -} - -/* - * pmu->start: start the event. - */ -static void riscv_pmu_start(struct perf_event *event, int flags) -{ - struct hw_perf_event *hwc = &event->hw; - - if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED))) - return; - - if (flags & PERF_EF_RELOAD) { - WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE)); - - /* - * Set the counter to the period to the next interrupt here, - * if you have any. - */ - } - - hwc->state = 0; - perf_event_update_userpage(event); - - /* - * Since we cannot write to counters, this serves as an initialization - * to the delta-mechanism in pmu->read(); otherwise, the delta would be - * wrong when pmu->read is called for the first time. - */ - local64_set(&hwc->prev_count, read_counter(hwc->idx)); -} - -/* - * pmu->add: add the event to PMU. - */ -static int riscv_pmu_add(struct perf_event *event, int flags) -{ - struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct hw_perf_event *hwc = &event->hw; - - if (cpuc->n_events == riscv_pmu->num_counters) - return -ENOSPC; - - /* - * We don't have general conunters, so no binding-event-to-counter - * process here. - * - * Indexing using hwc->config generally not works, since config may - * contain extra information, but here the only info we have in - * hwc->config is the event index. - */ - hwc->idx = hwc->config; - cpuc->events[hwc->idx] = event; - cpuc->n_events++; - - hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED; - - if (flags & PERF_EF_START) - riscv_pmu->pmu->start(event, PERF_EF_RELOAD); - - return 0; -} - -/* - * pmu->del: delete the event from PMU. - */ -static void riscv_pmu_del(struct perf_event *event, int flags) -{ - struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct hw_perf_event *hwc = &event->hw; - - cpuc->events[hwc->idx] = NULL; - cpuc->n_events--; - riscv_pmu->pmu->stop(event, PERF_EF_UPDATE); - perf_event_update_userpage(event); -} - -/* - * Interrupt: a skeletion for reference. - */ - -static DEFINE_MUTEX(pmc_reserve_mutex); - -static irqreturn_t riscv_base_pmu_handle_irq(int irq_num, void *dev) -{ - return IRQ_NONE; -} - -static int reserve_pmc_hardware(void) -{ - int err = 0; - - mutex_lock(&pmc_reserve_mutex); - if (riscv_pmu->irq >= 0 && riscv_pmu->handle_irq) { - err = request_irq(riscv_pmu->irq, riscv_pmu->handle_irq, - IRQF_PERCPU, "riscv-base-perf", NULL); - } - mutex_unlock(&pmc_reserve_mutex); - - return err; -} - -static void release_pmc_hardware(void) -{ - mutex_lock(&pmc_reserve_mutex); - if (riscv_pmu->irq >= 0) - free_irq(riscv_pmu->irq, NULL); - mutex_unlock(&pmc_reserve_mutex); -} - -/* - * Event Initialization/Finalization - */ - -static atomic_t riscv_active_events = ATOMIC_INIT(0); - -static void riscv_event_destroy(struct perf_event *event) -{ - if (atomic_dec_return(&riscv_active_events) == 0) - release_pmc_hardware(); -} - -static int riscv_event_init(struct perf_event *event) -{ - struct perf_event_attr *attr = &event->attr; - struct hw_perf_event *hwc = &event->hw; - int err; - int code; - - if (atomic_inc_return(&riscv_active_events) == 1) { - err = reserve_pmc_hardware(); - - if (err) { - pr_warn("PMC hardware not available\n"); - atomic_dec(&riscv_active_events); - return -EBUSY; - } - } - - switch (event->attr.type) { - case PERF_TYPE_HARDWARE: - code = riscv_pmu->map_hw_event(attr->config); - break; - case PERF_TYPE_HW_CACHE: - code = riscv_pmu->map_cache_event(attr->config); - break; - case PERF_TYPE_RAW: - return -EOPNOTSUPP; - default: - return -ENOENT; - } - - event->destroy = riscv_event_destroy; - if (code < 0) { - event->destroy(event); - return code; - } - - /* - * idx is set to -1 because the index of a general event should not be - * decided until binding to some counter in pmu->add(). - * - * But since we don't have such support, later in pmu->add(), we just - * use hwc->config as the index instead. - */ - hwc->config = code; - hwc->idx = -1; - - return 0; -} - -/* - * Initialization - */ - -static struct pmu min_pmu = { - .name = "riscv-base", - .event_init = riscv_event_init, - .add = riscv_pmu_add, - .del = riscv_pmu_del, - .start = riscv_pmu_start, - .stop = riscv_pmu_stop, - .read = riscv_pmu_read, -}; - -static const struct riscv_pmu riscv_base_pmu = { - .pmu = &min_pmu, - .max_events = ARRAY_SIZE(riscv_hw_event_map), - .map_hw_event = riscv_map_hw_event, - .hw_events = riscv_hw_event_map, - .map_cache_event = riscv_map_cache_event, - .cache_events = &riscv_cache_event_map, - .counter_width = 63, - .num_counters = RISCV_BASE_COUNTERS + 0, - .handle_irq = &riscv_base_pmu_handle_irq, - - /* This means this PMU has no IRQ. */ - .irq = -1, -}; - -static const struct of_device_id riscv_pmu_of_ids[] = { - {.compatible = "riscv,base-pmu", .data = &riscv_base_pmu}, - { /* sentinel value */ } -}; - -static int __init init_hw_perf_events(void) -{ - struct device_node *node = of_find_node_by_type(NULL, "pmu"); - const struct of_device_id *of_id; - - riscv_pmu = &riscv_base_pmu; - - if (node) { - of_id = of_match_node(riscv_pmu_of_ids, node); - - if (of_id) - riscv_pmu = of_id->data; - of_node_put(node); - } - - perf_pmu_register(riscv_pmu->pmu, "cpu", PERF_TYPE_RAW); - return 0; -} -arch_initcall(init_hw_perf_events); |