Re: [PATCH v9 2/2] ThunderX2, perf : Add Cavium ThunderX2 SoC UNCORE PMU driver
From: Suzuki K Poulose
Date: Thu Dec 06 2018 - 04:25:07 EST
Hi Ganpat,
On 05/12/2018 10:59, Kulkarni, Ganapatrao wrote:
This patch adds a perf driver for the PMU UNCORE devices DDR4 Memory
Controller(DMC) and Level 3 Cache(L3C). Each PMU supports up to 4
counters. All counters lack overflow interrupt and are
sampled periodically.
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxx>
---
drivers/perf/Kconfig | 9 +
drivers/perf/Makefile | 1 +
drivers/perf/thunderx2_pmu.c | 861 +++++++++++++++++++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
4 files changed, 872 insertions(+)
create mode 100644 drivers/perf/thunderx2_pmu.c
--- /dev/null
+++ b/drivers/perf/thunderx2_pmu.c
@@ -0,0 +1,861 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CAVIUM THUNDERX2 SoC PMU UNCORE
+ * Copyright (C) 2018 Cavium Inc.
+ * Author: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxx>
+ */
+
+#include <linux/acpi.h>
+#include <linux/cpuhotplug.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+
+/* Each ThunderX2(TX2) Socket has a L3C and DMC UNCORE PMU device.
+ * Each UNCORE PMU device consists of 4 independent programmable counters.
+ * Counters are 32 bit and do not support overflow interrupt,
+ * they need to be sampled before overflow(i.e, at every 2 seconds).
+ */
+
+#define TX2_PMU_MAX_COUNTERS 4
+#define TX2_PMU_DMC_CHANNELS 8
+#define TX2_PMU_L3_TILES 16
+
+#define TX2_PMU_HRTIMER_INTERVAL (2 * NSEC_PER_SEC)
+#define GET_EVENTID(ev) ((ev->hw.config) & 0x1f)
+#define GET_COUNTERID(ev) ((ev->hw.idx) & 0x3)
+ /* 1 byte per counter(4 counters).
+ * Event id is encoded in bits [5:1] of a byte,
+ */
+#define DMC_EVENT_CFG(idx, val) ((val) << (((idx) * 8) + 1))
+
+#define L3C_COUNTER_CTL 0xA8
+#define L3C_COUNTER_DATA 0xAC
+#define DMC_COUNTER_CTL 0x234
+#define DMC_COUNTER_DATA 0x240
+
+/* L3C event IDs */
+#define L3_EVENT_READ_REQ 0xD
+#define L3_EVENT_WRITEBACK_REQ 0xE
+#define L3_EVENT_INV_N_WRITE_REQ 0xF
+#define L3_EVENT_INV_REQ 0x10
+#define L3_EVENT_EVICT_REQ 0x13
+#define L3_EVENT_INV_N_WRITE_HIT 0x14
+#define L3_EVENT_INV_HIT 0x15
+#define L3_EVENT_READ_HIT 0x17
+#define L3_EVENT_MAX 0x18
+
+/* DMC event IDs */
+#define DMC_EVENT_COUNT_CYCLES 0x1
+#define DMC_EVENT_WRITE_TXNS 0xB
+#define DMC_EVENT_DATA_TRANSFERS 0xD
+#define DMC_EVENT_READ_TXNS 0xF
+#define DMC_EVENT_MAX 0x10
+
+enum tx2_uncore_type {
+ PMU_TYPE_L3C,
+ PMU_TYPE_DMC,
+ PMU_TYPE_INVALID,
+};
+
+/*
+ * pmu on each socket has 2 uncore devices(dmc and l3c),
+ * each device has 4 counters.
+ */
+struct tx2_uncore_pmu {
+ struct hlist_node hpnode;
+ struct list_head entry;
+ struct pmu pmu;
+ char *name;
+ int node;
+ int cpu;
+ u32 max_counters;
+ u32 prorate_factor;
+ u32 max_events;
+ u64 hrtimer_interval;
minor nit:
The alignment of the fields are pretty inconsistent. e.g,
u32 is followed by tabs and the rest are not. Please keep it
consistent.
+ void __iomem *base;
+ DECLARE_BITMAP(active_counters, TX2_PMU_MAX_COUNTERS);
+ struct perf_event *events[TX2_PMU_MAX_COUNTERS];
+ struct device *dev;
+ struct hrtimer hrtimer;
+ const struct attribute_group **attr_groups;
+ enum tx2_uncore_type type;
+ void (*init_cntr_base)(struct perf_event *event,
+ struct tx2_uncore_pmu *tx2_pmu);
+ void (*stop_event)(struct perf_event *event);
+ void (*start_event)(struct perf_event *event, int flags);
+};
+
+static LIST_HEAD(tx2_pmus);
+
+static inline struct tx2_uncore_pmu *pmu_to_tx2_pmu(struct pmu *pmu)
+{
+ return container_of(pmu, struct tx2_uncore_pmu, pmu);
+}
+
+PMU_FORMAT_ATTR(event, "config:0-4");
+
+static struct attribute *l3c_pmu_format_attrs[] = {
+ &format_attr_event.attr,
+ NULL,
+};
+
+static struct attribute *dmc_pmu_format_attrs[] = {
+ &format_attr_event.attr,
+ NULL,
+};
+
+static const struct attribute_group l3c_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = l3c_pmu_format_attrs,
+};
+
+static const struct attribute_group dmc_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = dmc_pmu_format_attrs,
+};
+
+/*
+ * sysfs event attributes
+ */
+static ssize_t tx2_pmu_event_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, "event=0x%lx\n", (unsigned long) eattr->var);
+}
+
+#define TX2_EVENT_ATTR(name, config) \
+ PMU_EVENT_ATTR(name, tx2_pmu_event_attr_##name, \
+ config, tx2_pmu_event_show)
+
+TX2_EVENT_ATTR(read_request, L3_EVENT_READ_REQ);
+TX2_EVENT_ATTR(writeback_request, L3_EVENT_WRITEBACK_REQ);
+TX2_EVENT_ATTR(inv_nwrite_request, L3_EVENT_INV_N_WRITE_REQ);
+TX2_EVENT_ATTR(inv_request, L3_EVENT_INV_REQ);
+TX2_EVENT_ATTR(evict_request, L3_EVENT_EVICT_REQ);
+TX2_EVENT_ATTR(inv_nwrite_hit, L3_EVENT_INV_N_WRITE_HIT);
+TX2_EVENT_ATTR(inv_hit, L3_EVENT_INV_HIT);
+TX2_EVENT_ATTR(read_hit, L3_EVENT_READ_HIT);
+
+static struct attribute *l3c_pmu_events_attrs[] = {
+ &tx2_pmu_event_attr_read_request.attr.attr,
+ &tx2_pmu_event_attr_writeback_request.attr.attr,
+ &tx2_pmu_event_attr_inv_nwrite_request.attr.attr,
+ &tx2_pmu_event_attr_inv_request.attr.attr,
+ &tx2_pmu_event_attr_evict_request.attr.attr,
+ &tx2_pmu_event_attr_inv_nwrite_hit.attr.attr,
+ &tx2_pmu_event_attr_inv_hit.attr.attr,
+ &tx2_pmu_event_attr_read_hit.attr.attr,
+ NULL,
+};
+
+TX2_EVENT_ATTR(cnt_cycles, DMC_EVENT_COUNT_CYCLES);
+TX2_EVENT_ATTR(write_txns, DMC_EVENT_WRITE_TXNS);
+TX2_EVENT_ATTR(data_transfers, DMC_EVENT_DATA_TRANSFERS);
+TX2_EVENT_ATTR(read_txns, DMC_EVENT_READ_TXNS);
+
+static struct attribute *dmc_pmu_events_attrs[] = {
+ &tx2_pmu_event_attr_cnt_cycles.attr.attr,
+ &tx2_pmu_event_attr_write_txns.attr.attr,
+ &tx2_pmu_event_attr_data_transfers.attr.attr,
+ &tx2_pmu_event_attr_read_txns.attr.attr,
+ NULL,
+};
+
+static const struct attribute_group l3c_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = l3c_pmu_events_attrs,
+};
+
+static const struct attribute_group dmc_pmu_events_attr_group = {
+ .name = "events",
+ .attrs = dmc_pmu_events_attrs,
+};
+
+/*
+ * sysfs cpumask attributes
+ */
+static ssize_t cpumask_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tx2_uncore_pmu *tx2_pmu;
+
+ tx2_pmu = pmu_to_tx2_pmu(dev_get_drvdata(dev));
+ return cpumap_print_to_pagebuf(true, buf, cpumask_of(tx2_pmu->cpu));
+}
+static DEVICE_ATTR_RO(cpumask);
+
+static struct attribute *tx2_pmu_cpumask_attrs[] = {
+ &dev_attr_cpumask.attr,
+ NULL,
+};
+
+static const struct attribute_group pmu_cpumask_attr_group = {
+ .attrs = tx2_pmu_cpumask_attrs,
+};
+
+/*
+ * Per PMU device attribute groups
+ */
+static const struct attribute_group *l3c_pmu_attr_groups[] = {
+ &l3c_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &l3c_pmu_events_attr_group,
+ NULL
+};
+
+static const struct attribute_group *dmc_pmu_attr_groups[] = {
+ &dmc_pmu_format_attr_group,
+ &pmu_cpumask_attr_group,
+ &dmc_pmu_events_attr_group,
+ NULL
+};
+
+static inline u32 reg_readl(unsigned long addr)
+{
+ return readl((void __iomem *)addr);
+}
+
+static inline void reg_writel(u32 val, unsigned long addr)
+{
+ writel(val, (void __iomem *)addr);
+}
+
+static int alloc_counter(struct tx2_uncore_pmu *tx2_pmu)
+{
+ int counter;
+
+ counter = find_first_zero_bit(tx2_pmu->active_counters,
+ tx2_pmu->max_counters);
+ if (counter == tx2_pmu->max_counters)
+ return -ENOSPC;
+
+ set_bit(counter, tx2_pmu->active_counters);
+ return counter;
+}
+
+static inline void free_counter(struct tx2_uncore_pmu *tx2_pmu, int counter)
+{
+ clear_bit(counter, tx2_pmu->active_counters);
+}
+
+static void init_cntr_base_l3c(struct perf_event *event,
+ struct tx2_uncore_pmu *tx2_pmu)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ /* counter ctrl/data reg offset at 8 */
+ hwc->config_base = (unsigned long)tx2_pmu->base
+ + L3C_COUNTER_CTL + (8 * GET_COUNTERID(event));
+ hwc->event_base = (unsigned long)tx2_pmu->base
+ + L3C_COUNTER_DATA + (8 * GET_COUNTERID(event));
+}
+
+static void init_cntr_base_dmc(struct perf_event *event,
+ struct tx2_uncore_pmu *tx2_pmu)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ hwc->config_base = (unsigned long)tx2_pmu->base
+ + DMC_COUNTER_CTL;
+ /* counter data reg offset at 0xc */
+ hwc->event_base = (unsigned long)tx2_pmu->base
+ + DMC_COUNTER_DATA + (0xc * GET_COUNTERID(event));
+}
+
+static void uncore_start_event_l3c(struct perf_event *event, int flags)
+{
+ u32 val;
+ struct hw_perf_event *hwc = &event->hw;
+
+ /* event id encoded in bits [07:03] */
+ val = GET_EVENTID(event) << 3;
+ reg_writel(val, hwc->config_base);
+ local64_set(&hwc->prev_count, 0);
+ reg_writel(0, hwc->event_base);
+}
+
+static inline void uncore_stop_event_l3c(struct perf_event *event)
+{
+ reg_writel(0, event->hw.config_base);
+}
+
+static void uncore_start_event_dmc(struct perf_event *event, int flags)
+{
+ u32 val;
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = GET_COUNTERID(event);
+ int event_id = GET_EVENTID(event);
+
+ /* enable and start counters.
+ * 8 bits for each counter, bits[05:01] of a counter to set event type.
+ */
+ val = reg_readl(hwc->config_base);
+ val &= ~DMC_EVENT_CFG(idx, 0x1f);
+ val |= DMC_EVENT_CFG(idx, event_id);
+ reg_writel(val, hwc->config_base);
+ local64_set(&hwc->prev_count, 0);
+ reg_writel(0, hwc->event_base);
+}
+
+static void uncore_stop_event_dmc(struct perf_event *event)
+{
+ u32 val;
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = GET_COUNTERID(event);
+
+ /* clear event type(bits[05:01]) to stop counter */
+ val = reg_readl(hwc->config_base);
+ val &= ~DMC_EVENT_CFG(idx, 0x1f);
+ reg_writel(val, hwc->config_base);
+}
+
+static void tx2_uncore_event_update(struct perf_event *event)
+{
+ s64 prev, delta, new = 0;
+ struct hw_perf_event *hwc = &event->hw;
+ struct tx2_uncore_pmu *tx2_pmu;
+ enum tx2_uncore_type type;
+ u32 prorate_factor;
+
+ tx2_pmu = pmu_to_tx2_pmu(event->pmu);
+ type = tx2_pmu->type;
+ prorate_factor = tx2_pmu->prorate_factor;
+
+ new = reg_readl(hwc->event_base);
+ prev = local64_xchg(&hwc->prev_count, new);
+
+ /* handles rollover of 32 bit counter */
+ delta = (u32)(((1UL << 32) - prev) + new);
+
+ /* DMC event data_transfers granularity is 16 Bytes, convert it to 64 */
+ if (type == PMU_TYPE_DMC &&
+ GET_EVENTID(event) == DMC_EVENT_DATA_TRANSFERS)
+ delta = delta/4;
+
+ /* L3C and DMC has 16 and 8 interleave channels respectively.
+ * The sampled value is for channel 0 and multiplied with
+ * prorate_factor to get the count for a device.
+ */
+ local64_add(delta * prorate_factor, &event->count);
+}
+
+enum tx2_uncore_type get_tx2_pmu_type(struct acpi_device *adev)
+{
+ int i = 0;
+ struct acpi_tx2_pmu_device {
+ __u8 id[ACPI_ID_LEN];
+ enum tx2_uncore_type type;
+ } devices[] = {
+ {"CAV901D", PMU_TYPE_L3C},
+ {"CAV901F", PMU_TYPE_DMC},
+ {"", PMU_TYPE_INVALID}
+ };
+
+ while (devices[i].type != PMU_TYPE_INVALID) {
+ if (!strcmp(acpi_device_hid(adev), devices[i].id))
+ break;
+ i++;
+ }
+
+ return devices[i].type;
+}
+
+static bool tx2_uncore_validate_event(struct pmu *pmu,
+ struct perf_event *event, int *counters)
+{
+ if (is_software_event(event))
+ return true;
+ /* Reject groups spanning multiple HW PMUs. */
+ if (event->pmu != pmu)
+ return false;
+
+ *counters = *counters + 1;
+ return true;
nit: alignment.
Otherwise looks good to me.
FWIW, with the above nits fixed:
Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>