diff options
| -rw-r--r-- | Documentation/perf/qcom_l3_pmu.txt | 25 | ||||
| -rw-r--r-- | drivers/perf/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/perf/Makefile | 1 | ||||
| -rw-r--r-- | drivers/perf/qcom_l3_pmu.c | 849 | ||||
| -rw-r--r-- | include/linux/cpuhotplug.h | 1 |
5 files changed, 886 insertions, 0 deletions
diff --git a/Documentation/perf/qcom_l3_pmu.txt b/Documentation/perf/qcom_l3_pmu.txt new file mode 100644 index 000000000000..96b3a9444a0d --- /dev/null +++ b/Documentation/perf/qcom_l3_pmu.txt @@ -0,0 +1,25 @@ +Qualcomm Datacenter Technologies L3 Cache Performance Monitoring Unit (PMU) +=========================================================================== + +This driver supports the L3 cache PMUs found in Qualcomm Datacenter Technologies +Centriq SoCs. The L3 cache on these SOCs is composed of multiple slices, shared +by all cores within a socket. Each slice is exposed as a separate uncore perf +PMU with device name l3cache_<socket>_<instance>. User space is responsible +for aggregating across slices. + +The driver provides a description of its available events and configuration +options in sysfs, see /sys/devices/l3cache*. Given that these are uncore PMUs +the driver also exposes a "cpumask" sysfs attribute which contains a mask +consisting of one CPU per socket which will be used to handle all the PMU +events on that socket. + +The hardware implements 32bit event counters and has a flat 8bit event space +exposed via the "event" format attribute. In addition to the 32bit physical +counters the driver supports virtual 64bit hardware counters by using hardware +counter chaining. This feature is exposed via the "lc" (long counter) format +flag. E.g.: + + perf stat -e l3cache_0_0/read-miss,lc/ + +Given that these are uncore PMUs the driver does not support sampling, therefore +"perf record" will not work. Per-task perf sessions are not supported. diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig index 93651907874f..c436e0d303e7 100644 --- a/drivers/perf/Kconfig +++ b/drivers/perf/Kconfig @@ -21,6 +21,16 @@ config QCOM_L2_PMU Adds the L2 cache PMU into the perf events subsystem for monitoring L2 cache events. +config QCOM_L3_PMU + bool "Qualcomm Technologies L3-cache PMU" + depends on ARCH_QCOM && ARM64 && PERF_EVENTS && ACPI + select QCOM_IRQ_COMBINER + help + Provides support for the L3 cache performance monitor unit (PMU) + in Qualcomm Technologies processors. + Adds the L3 cache PMU into the perf events subsystem for + monitoring L3 cache events. + config XGENE_PMU depends on PERF_EVENTS && ARCH_XGENE bool "APM X-Gene SoC PMU" diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile index ef24833c94a8..ef0c6b210345 100644 --- a/drivers/perf/Makefile +++ b/drivers/perf/Makefile @@ -1,3 +1,4 @@ obj-$(CONFIG_ARM_PMU) += arm_pmu.o obj-$(CONFIG_QCOM_L2_PMU) += qcom_l2_pmu.o +obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o diff --git a/drivers/perf/qcom_l3_pmu.c b/drivers/perf/qcom_l3_pmu.c new file mode 100644 index 000000000000..7f6b62b29e9d --- /dev/null +++ b/drivers/perf/qcom_l3_pmu.c @@ -0,0 +1,849 @@ +/* + * Driver for the L3 cache PMUs in Qualcomm Technologies chips. + * + * The driver supports a distributed cache architecture where the overall + * cache for a socket is comprised of multiple slices each with its own PMU. + * Access to each individual PMU is provided even though all CPUs share all + * the slices. User space needs to aggregate to individual counts to provide + * a global picture. + * + * See Documentation/perf/qcom_l3_pmu.txt for more details. + * + * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only 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. + */ + +#include <linux/acpi.h> +#include <linux/bitops.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/perf_event.h> +#include <linux/platform_device.h> + +/* + * General constants + */ + +/* Number of counters on each PMU */ +#define L3_NUM_COUNTERS 8 +/* Mask for the event type field within perf_event_attr.config and EVTYPE reg */ +#define L3_EVTYPE_MASK 0xFF +/* + * Bit position of the 'long counter' flag within perf_event_attr.config. + * Reserve some space between the event type and this flag to allow expansion + * in the event type field. + */ +#define L3_EVENT_LC_BIT 32 + +/* + * Register offsets + */ + +/* Perfmon registers */ +#define L3_HML3_PM_CR 0x000 +#define L3_HML3_PM_EVCNTR(__cntr) (0x420 + ((__cntr) & 0x7) * 8) +#define L3_HML3_PM_CNTCTL(__cntr) (0x120 + ((__cntr) & 0x7) * 8) +#define L3_HML3_PM_EVTYPE(__cntr) (0x220 + ((__cntr) & 0x7) * 8) +#define L3_HML3_PM_FILTRA 0x300 +#define L3_HML3_PM_FILTRB 0x308 +#define L3_HML3_PM_FILTRC 0x310 +#define L3_HML3_PM_FILTRAM 0x304 +#define L3_HML3_PM_FILTRBM 0x30C +#define L3_HML3_PM_FILTRCM 0x314 + +/* Basic counter registers */ +#define L3_M_BC_CR 0x500 +#define L3_M_BC_SATROLL_CR 0x504 +#define L3_M_BC_CNTENSET 0x508 +#define L3_M_BC_CNTENCLR 0x50C +#define L3_M_BC_INTENSET 0x510 +#define L3_M_BC_INTENCLR 0x514 +#define L3_M_BC_GANG 0x718 +#define L3_M_BC_OVSR 0x740 +#define L3_M_BC_IRQCTL 0x96C + +/* + * Bit field definitions + */ + +/* L3_HML3_PM_CR */ +#define PM_CR_RESET (0) + +/* L3_HML3_PM_XCNTCTL/L3_HML3_PM_CNTCTLx */ +#define PMCNT_RESET (0) + +/* L3_HML3_PM_EVTYPEx */ +#define EVSEL(__val) ((__val) & L3_EVTYPE_MASK) + +/* Reset value for all the filter registers */ +#define PM_FLTR_RESET (0) + +/* L3_M_BC_CR */ +#define BC_RESET (1UL << 1) +#define BC_ENABLE (1UL << 0) + +/* L3_M_BC_SATROLL_CR */ +#define BC_SATROLL_CR_RESET (0) + +/* L3_M_BC_CNTENSET */ +#define PMCNTENSET(__cntr) (1UL << ((__cntr) & 0x7)) + +/* L3_M_BC_CNTENCLR */ +#define PMCNTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) +#define BC_CNTENCLR_RESET (0xFF) + +/* L3_M_BC_INTENSET */ +#define PMINTENSET(__cntr) (1UL << ((__cntr) & 0x7)) + +/* L3_M_BC_INTENCLR */ +#define PMINTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) +#define BC_INTENCLR_RESET (0xFF) + +/* L3_M_BC_GANG */ +#define GANG_EN(__cntr) (1UL << ((__cntr) & 0x7)) +#define BC_GANG_RESET (0) + +/* L3_M_BC_OVSR */ +#define PMOVSRCLR(__cntr) (1UL << ((__cntr) & 0x7)) +#define PMOVSRCLR_RESET (0xFF) + +/* L3_M_BC_IRQCTL */ +#define PMIRQONMSBEN(__cntr) (1UL << ((__cntr) & 0x7)) +#define BC_IRQCTL_RESET (0x0) + +/* + * Events + */ + +#define L3_EVENT_CYCLES 0x01 +#define L3_EVENT_READ_HIT 0x20 +#define L3_EVENT_READ_MISS 0x21 +#define L3_EVENT_READ_HIT_D 0x22 +#define L3_EVENT_READ_MISS_D 0x23 +#define L3_EVENT_WRITE_HIT 0x24 +#define L3_EVENT_WRITE_MISS 0x25 + +/* + * Decoding of settings from perf_event_attr + * + * The config format for perf events is: + * - config: bits 0-7: event type + * bit 32: HW counter size requested, 0: 32 bits, 1: 64 bits + */ + +static inline u32 get_event_type(struct perf_event *event) +{ + return (event->attr.config) & L3_EVTYPE_MASK; +} + +static inline bool event_uses_long_counter(struct perf_event *event) +{ + return !!(event->attr.config & BIT_ULL(L3_EVENT_LC_BIT)); +} + +static inline int event_num_counters(struct perf_event *event) +{ + return event_uses_long_counter(event) ? 2 : 1; +} + +/* + * Main PMU, inherits from the core perf PMU type + */ +struct l3cache_pmu { + struct pmu pmu; + struct hlist_node node; + void __iomem *regs; + struct perf_event *events[L3_NUM_COUNTERS]; + unsigned long used_mask[BITS_TO_LONGS(L3_NUM_COUNTERS)]; + cpumask_t cpumask; +}; + +#define to_l3cache_pmu(p) (container_of(p, struct l3cache_pmu, pmu)) + +/* + * Type used to group hardware counter operations + * + * Used to implement two types of hardware counters, standard (32bits) and + * long (64bits). The hardware supports counter chaining which we use to + * implement long counters. This support is exposed via the 'lc' flag field + * in perf_event_attr.config. + */ +struct l3cache_event_ops { + /* Called to start event monitoring */ + void (*start)(struct perf_event *event); + /* Called to stop event monitoring */ + void (*stop)(struct perf_event *event, int flags); + /* Called to update the perf_event */ + void (*update)(struct perf_event *event); +}; + +/* + * Implementation of long counter operations + * + * 64bit counters are implemented by chaining two of the 32bit physical + * counters. The PMU only supports chaining of adjacent even/odd pairs + * and for simplicity the driver always configures the odd counter to + * count the overflows of the lower-numbered even counter. Note that since + * the resulting hardware counter is 64bits no IRQs are required to maintain + * the software counter which is also 64bits. + */ + +static void qcom_l3_cache__64bit_counter_start(struct perf_event *event) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 evsel = get_event_type(event); + u32 gang; + + /* Set the odd counter to count the overflows of the even counter */ + gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); + gang |= GANG_EN(idx + 1); + writel_relaxed(gang, l3pmu->regs + L3_M_BC_GANG); + + /* Initialize the hardware counters and reset prev_count*/ + local64_set(&event->hw.prev_count, 0); + writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); + writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); + + /* + * Set the event types, the upper half must use zero and the lower + * half the actual event type + */ + writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(idx + 1)); + writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); + + /* Finally, enable the counters */ + writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx + 1)); + writel_relaxed(PMCNTENSET(idx + 1), l3pmu->regs + L3_M_BC_CNTENSET); + writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); + writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); +} + +static void qcom_l3_cache__64bit_counter_stop(struct perf_event *event, + int flags) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); + + /* Disable the counters */ + writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); + writel_relaxed(PMCNTENCLR(idx + 1), l3pmu->regs + L3_M_BC_CNTENCLR); + + /* Disable chaining */ + writel_relaxed(gang & ~GANG_EN(idx + 1), l3pmu->regs + L3_M_BC_GANG); +} + +static void qcom_l3_cache__64bit_counter_update(struct perf_event *event) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 hi, lo; + u64 prev, new; + + do { + prev = local64_read(&event->hw.prev_count); + do { + hi = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); + lo = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); + } while (hi != readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1))); + new = ((u64)hi << 32) | lo; + } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); + + local64_add(new - prev, &event->count); +} + +static const struct l3cache_event_ops event_ops_long = { + .start = qcom_l3_cache__64bit_counter_start, + .stop = qcom_l3_cache__64bit_counter_stop, + .update = qcom_l3_cache__64bit_counter_update, +}; + +/* + * Implementation of standard counter operations + * + * 32bit counters use a single physical counter and a hardware feature that + * asserts the overflow IRQ on the toggling of the most significant bit in + * the counter. This feature allows the counters to be left free-running + * without needing the usual reprogramming required to properly handle races + * during concurrent calls to update. + */ + +static void qcom_l3_cache__32bit_counter_start(struct perf_event *event) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 evsel = get_event_type(event); + u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); + + /* Set the counter to assert the overflow IRQ on MSB toggling */ + writel_relaxed(irqctl | PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); + + /* Initialize the hardware counter and reset prev_count*/ + local64_set(&event->hw.prev_count, 0); + writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); + + /* Set the event type */ + writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); + + /* Enable interrupt generation by this counter */ + writel_relaxed(PMINTENSET(idx), l3pmu->regs + L3_M_BC_INTENSET); + + /* Finally, enable the counter */ + writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); + writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); +} + +static void qcom_l3_cache__32bit_counter_stop(struct perf_event *event, + int flags) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); + + /* Disable the counter */ + writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); + + /* Disable interrupt generation by this counter */ + writel_relaxed(PMINTENCLR(idx), l3pmu->regs + L3_M_BC_INTENCLR); + + /* Set the counter to not assert the overflow IRQ on MSB toggling */ + writel_relaxed(irqctl & ~PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); +} + +static void qcom_l3_cache__32bit_counter_update(struct perf_event *event) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + int idx = event->hw.idx; + u32 prev, new; + + do { + prev = local64_read(&event->hw.prev_count); + new = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); + } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); + + local64_add(new - prev, &event->count); +} + +static const struct l3cache_event_ops event_ops_std = { + .start = qcom_l3_cache__32bit_counter_start, + .stop = qcom_l3_cache__32bit_counter_stop, + .update = qcom_l3_cache__32bit_counter_update, +}; + +/* Retrieve the appropriate operations for the given event */ +static +const struct l3cache_event_ops *l3cache_event_get_ops(struct perf_event *event) +{ + if (event_uses_long_counter(event)) + return &event_ops_long; + else + return &event_ops_std; +} + +/* + * Top level PMU functions. + */ + +static inline void qcom_l3_cache__init(struct l3cache_pmu *l3pmu) +{ + int i; + + writel_relaxed(BC_RESET, l3pmu->regs + L3_M_BC_CR); + + /* + * Use writel for the first programming command to ensure the basic + * counter unit is stopped before proceeding + */ + writel(BC_SATROLL_CR_RESET, l3pmu->regs + L3_M_BC_SATROLL_CR); + + writel_relaxed(BC_CNTENCLR_RESET, l3pmu->regs + L3_M_BC_CNTENCLR); + writel_relaxed(BC_INTENCLR_RESET, l3pmu->regs + L3_M_BC_INTENCLR); + writel_relaxed(PMOVSRCLR_RESET, l3pmu->regs + L3_M_BC_OVSR); + writel_relaxed(BC_GANG_RESET, l3pmu->regs + L3_M_BC_GANG); + writel_relaxed(BC_IRQCTL_RESET, l3pmu->regs + L3_M_BC_IRQCTL); + writel_relaxed(PM_CR_RESET, l3pmu->regs + L3_HML3_PM_CR); + + for (i = 0; i < L3_NUM_COUNTERS; ++i) { + writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(i)); + writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(i)); + } + + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRA); + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRAM); + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRB); + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRBM); + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRC); + writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRCM); + + /* + * Use writel here to ensure all programming commands are done + * before proceeding + */ + writel(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); +} + +static irqreturn_t qcom_l3_cache__handle_irq(int irq_num, void *data) +{ + struct l3cache_pmu *l3pmu = data; + /* Read the overflow status register */ + long status = readl_relaxed(l3pmu->regs + L3_M_BC_OVSR); + int idx; + + if (status == 0) + return IRQ_NONE; + + /* Clear the bits we read on the overflow status register */ + writel_relaxed(status, l3pmu->regs + L3_M_BC_OVSR); + + for_each_set_bit(idx, &status, L3_NUM_COUNTERS) { + struct perf_event *event; + const struct l3cache_event_ops *ops; + + event = l3pmu->events[idx]; + if (!event) + continue; + + /* + * Since the IRQ is not enabled for events using long counters + * we should never see one of those here, however, be consistent + * and use the ops indirections like in the other operations. + */ + + ops = l3cache_event_get_ops(event); + ops->update(event); + } + + return IRQ_HANDLED; +} + +/* + * Implementation of abstract pmu functionality required by + * the core perf events code. + */ + +static void qcom_l3_cache__pmu_enable(struct pmu *pmu) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); + + /* Ensure the other programming commands are observed before enabling */ + wmb(); + + writel_relaxed(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); +} + +static void qcom_l3_cache__pmu_disable(struct pmu *pmu) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); + + writel_relaxed(0, l3pmu->regs + L3_M_BC_CR); + + /* Ensure the basic counter unit is stopped before proceeding */ + wmb(); +} + +/* + * We must NOT create groups containing events from multiple hardware PMUs, + * although mixing different software and hardware PMUs is allowed. + */ +static bool qcom_l3_cache__validate_event_group(struct perf_event *event) +{ + struct perf_event *leader = event->group_leader; + struct perf_event *sibling; + int counters = 0; + + if (leader->pmu != event->pmu && !is_software_event(leader)) + return false; + + counters = event_num_counters(event); + counters += event_num_counters(leader); + + list_for_each_entry(sibling, &leader->sibling_list, group_entry) { + if (is_software_event(sibling)) + continue; + if (sibling->pmu != event->pmu) + return false; + counters += event_num_counters(sibling); + } + + /* + * If the group requires more counters than the HW has, it + * cannot ever be scheduled. + */ + return counters <= L3_NUM_COUNTERS; +} + +static int qcom_l3_cache__event_init(struct perf_event *event) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + + /* + * Is the event for this PMU? + */ + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* + * There are no per-counter mode filters in the PMU. + */ + if (event->attr.exclude_user || event->attr.exclude_kernel || + event->attr.exclude_hv || event->attr.exclude_idle) + return -EINVAL; + + /* + * Sampling not supported since these events are not core-attributable. + */ + if (hwc->sample_period) + return -EINVAL; + + /* + * Task mode not available, we run the counters as socket counters, + * not attributable to any CPU and therefore cannot attribute per-task. + */ + if (event->cpu < 0) + return -EINVAL; + + /* Validate the group */ + if (!qcom_l3_cache__validate_event_group(event)) + return -EINVAL; + + hwc->idx = -1; + + /* + * Many perf core operations (eg. events rotation) operate on a + * single CPU context. This is obvious for CPU PMUs, where one + * expects the same sets of events being observed on all CPUs, + * but can lead to issues for off-core PMUs, like this one, where + * each event could be theoretically assigned to a different CPU. + * To mitigate this, we enforce CPU assignment to one designated + * processor (the one described in the "cpumask" attribute exported + * by the PMU device). perf user space tools honor this and avoid + * opening more than one copy of the events. + */ + event->cpu = cpumask_first(&l3pmu->cpumask); + + return 0; +} + +static void qcom_l3_cache__event_start(struct perf_event *event, int flags) +{ + struct hw_perf_event *hwc = &event->hw; + const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); + + hwc->state = 0; + ops->start(event); +} + +static void qcom_l3_cache__event_stop(struct perf_event *event, int flags) +{ + struct hw_perf_event *hwc = &event->hw; + const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); + + if (hwc->state & PERF_HES_STOPPED) + return; + + ops->stop(event, flags); + if (flags & PERF_EF_UPDATE) + ops->update(event); + hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; +} + +static int qcom_l3_cache__event_add(struct perf_event *event, int flags) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + int order = event_uses_long_counter(event) ? 1 : 0; + int idx; + + /* + * Try to allocate a counter. + */ + idx = bitmap_find_free_region(l3pmu->used_mask, L3_NUM_COUNTERS, order); + if (idx < 0) + /* The counters are all in use. */ + return -EAGAIN; + + hwc->idx = idx; + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; + l3pmu->events[idx] = event; + + if (flags & PERF_EF_START) + qcom_l3_cache__event_start(event, 0); + + /* Propagate changes to the userspace mapping. */ + perf_event_update_userpage(event); + + return 0; +} + +static void qcom_l3_cache__event_del(struct perf_event *event, int flags) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + int order = event_uses_long_counter(event) ? 1 : 0; + + /* Stop and clean up */ + qcom_l3_cache__event_stop(event, flags | PERF_EF_UPDATE); + l3pmu->events[hwc->idx] = NULL; + bitmap_release_region(l3pmu->used_mask, hwc->idx, order); + + /* Propagate changes to the userspace mapping. */ + perf_event_update_userpage(event); +} + +static void qcom_l3_cache__event_read(struct perf_event *event) +{ + const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); + + ops->update(event); +} + +/* + * Add sysfs attributes + * + * We export: + * - formats, used by perf user space and other tools to configure events + * - events, used by perf user space and other tools to create events + * symbolically, e.g.: + * perf stat -a -e l3cache_0_0/event=read-miss/ ls + * perf stat -a -e l3cache_0_0/event=0x21/ ls + * - cpumask, used by perf user space and other tools to know on which CPUs + * to open the events + */ + +/* formats */ + +static ssize_t l3cache_pmu_format_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_ext_attribute *eattr; + + eattr = container_of(attr, struct dev_ext_attribute, attr); + return sprintf(buf, "%s\n", (char *) eattr->var); +} + +#define L3CACHE_PMU_FORMAT_ATTR(_name, _config) \ + (&((struct dev_ext_attribute[]) { \ + { .attr = __ATTR(_name, 0444, l3cache_pmu_format_show, NULL), \ + .var = (void *) _config, } \ + })[0].attr.attr) + +static struct attribute *qcom_l3_cache_pmu_formats[] = { + L3CACHE_PMU_FORMAT_ATTR(event, "config:0-7"), + L3CACHE_PMU_FORMAT_ATTR(lc, "config:" __stringify(L3_EVENT_LC_BIT)), + NULL, +}; + +static struct attribute_group qcom_l3_cache_pmu_format_group = { + .name = "format", + .attrs = qcom_l3_cache_pmu_formats, +}; + +/* events */ + +static ssize_t l3cache_pmu_event_show(struct device *dev, + struct device_attribute *attr, char *page) +{ + struct perf_pmu_events_attr *pmu_attr; + + pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); + return sprintf(page, "event=0x%02llx\n", pmu_attr->id); +} + +#define L3CACHE_EVENT_ATTR(_name, _id) \ + (&((struct perf_pmu_events_attr[]) { \ + { .attr = __ATTR(_name, 0444, l3cache_pmu_event_show, NULL), \ + .id = _id, } \ + })[0].attr.attr) + +static struct attribute *qcom_l3_cache_pmu_events[] = { + L3CACHE_EVENT_ATTR(cycles, L3_EVENT_CYCLES), + L3CACHE_EVENT_ATTR(read-hit, L3_EVENT_READ_HIT), + L3CACHE_EVENT_ATTR(read-miss, L3_EVENT_READ_MISS), + L3CACHE_EVENT_ATTR(read-hit-d-side, L3_EVENT_READ_HIT_D), + L3CACHE_EVENT_ATTR(read-miss-d-side, L3_EVENT_READ_MISS_D), + L3CACHE_EVENT_ATTR(write-hit, L3_EVENT_WRITE_HIT), + L3CACHE_EVENT_ATTR(write-miss, L3_EVENT_WRITE_MISS), + NULL +}; + +static struct attribute_group qcom_l3_cache_pmu_events_group = { + .name = "events", + .attrs = qcom_l3_cache_pmu_events, +}; + +/* cpumask */ + +static ssize_t qcom_l3_cache_pmu_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct l3cache_pmu *l3pmu = to_l3cache_pmu(dev_get_drvdata(dev)); + + return cpumap_print_to_pagebuf(true, buf, &l3pmu->cpumask); +} + +static DEVICE_ATTR(cpumask, 0444, qcom_l3_cache_pmu_cpumask_show, NULL); + +static struct attribute *qcom_l3_cache_pmu_cpumask_attrs[] = { + &dev_attr_cpumask.attr, + NULL, +}; + +static struct attribute_group qcom_l3_cache_pmu_cpumask_attr_group = { + .attrs = qcom_l3_cache_pmu_cpumask_attrs, +}; + +/* + * Per PMU device attribute groups + */ +static const struct attribute_group *qcom_l3_cache_pmu_attr_grps[] = { + &qcom_l3_cache_pmu_format_group, + &qcom_l3_cache_pmu_events_group, + &qcom_l3_cache_pmu_cpumask_attr_group, + NULL, +}; + +/* + * Probing functions and data. + */ + +static int qcom_l3_cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node) +{ + struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); + + /* If there is not a CPU/PMU association pick this CPU */ + if (cpumask_empty(&l3pmu->cpumask)) + cpumask_set_cpu(cpu, &l3pmu->cpumask); + + return 0; +} + +static int qcom_l3_cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node) +{ + struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); + unsigned int target; + + if (!cpumask_test_and_clear_cpu(cpu, &l3pmu->cpumask)) + return 0; + target = cpumask_any_but(cpu_online_mask, cpu); + if (target >= nr_cpu_ids) + return 0; + perf_pmu_migrate_context(&l3pmu->pmu, cpu, target); + cpumask_set_cpu(target, &l3pmu->cpumask); + return 0; +} + +static int qcom_l3_cache_pmu_probe(struct platform_device *pdev) +{ + struct l3cache_pmu *l3pmu; + struct acpi_device *acpi_dev; + struct resource *memrc; + int ret; + char *name; + + /* Initialize the PMU data structures */ + + acpi_dev = ACPI_COMPANION(&pdev->dev); + if (!acpi_dev) + return -ENODEV; + + l3pmu = devm_kzalloc(&pdev->dev, sizeof(*l3pmu), GFP_KERNEL); + name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "l3cache_%s_%s", + acpi_dev->parent->pnp.unique_id, acpi_dev->pnp.unique_id); + if (!l3pmu || !name) + return -ENOMEM; + + l3pmu->pmu = (struct pmu) { + .task_ctx_nr = perf_invalid_context, + + .pmu_enable = qcom_l3_cache__pmu_enable, + .pmu_disable = qcom_l3_cache__pmu_disable, + .event_init = qcom_l3_cache__event_init, + .add = qcom_l3_cache__event_add, + .del = qcom_l3_cache__event_del, + .start = qcom_l3_cache__event_start, + .stop = qcom_l3_cache__event_stop, + .read = qcom_l3_cache__event_read, + + .attr_groups = qcom_l3_cache_pmu_attr_grps, + }; + + memrc = platform_get_resource(pdev, IORESOURCE_MEM, 0); + l3pmu->regs = devm_ioremap_resource(&pdev->dev, memrc); + if (IS_ERR(l3pmu->regs)) { + dev_err(&pdev->dev, "Can't map PMU @%pa\n", &memrc->start); + return PTR_ERR(l3pmu->regs); + } + + qcom_l3_cache__init(l3pmu); + + ret = platform_get_irq(pdev, 0); + if (ret <= 0) + return ret; + + ret = devm_request_irq(&pdev->dev, ret, qcom_l3_cache__handle_irq, 0, + name, l3pmu); + if (ret) { + dev_err(&pdev->dev, "Request for IRQ failed for slice @%pa\n", + &memrc->start); + return ret; + } + + /* Add this instance to the list used by the offline callback */ + ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, &l3pmu->node); + if (ret) { + dev_err(&pdev->dev, "Error %d registering hotplug", ret); + return ret; + } + + ret = perf_pmu_register(&l3pmu->pmu, name, -1); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to register L3 cache PMU (%d)\n", ret); + return ret; + } + + dev_info(&pdev->dev, "Registered %s, type: %d\n", name, l3pmu->pmu.type); + + return 0; +} + +static const struct acpi_device_id qcom_l3_cache_pmu_acpi_match[] = { + { "QCOM8081", }, + { } +}; +MODULE_DEVICE_TABLE(acpi, qcom_l3_cache_pmu_acpi_match); + +static struct platform_driver qcom_l3_cache_pmu_driver = { + .driver = { + .name = "qcom-l3cache-pmu", + .acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match), + }, + .probe = qcom_l3_cache_pmu_probe, +}; + +static int __init register_qcom_l3_cache_pmu_driver(void) +{ + int ret; + + /* Install a hook to update the reader CPU in case it goes offline */ + ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, + "perf/qcom/l3cache:online", + qcom_l3_cache_pmu_online_cpu, + qcom_l3_cache_pmu_offline_cpu); + if (ret) + return ret; + + return platform_driver_register(&qcom_l3_cache_pmu_driver); +} +device_initcall(register_qcom_l3_cache_pmu_driver); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 62d240e962f0..cfcfab37d9c4 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -137,6 +137,7 @@ enum cpuhp_state { CPUHP_AP_PERF_ARM_CCN_ONLINE, CPUHP_AP_PERF_ARM_L2X0_ONLINE, CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE, + CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, CPUHP_AP_WORKQUEUE_ONLINE, CPUHP_AP_RCUTREE_ONLINE, CPUHP_AP_ONLINE_DYN, |