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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /arch/powerpc/perf/hv-gpci.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/perf/hv-gpci.c')
-rw-r--r-- | arch/powerpc/perf/hv-gpci.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/arch/powerpc/perf/hv-gpci.c b/arch/powerpc/perf/hv-gpci.c new file mode 100644 index 000000000..28b770bbc --- /dev/null +++ b/arch/powerpc/perf/hv-gpci.c @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Hypervisor supplied "gpci" ("get performance counter info") performance + * counter support + * + * Author: Cody P Schafer <cody@linux.vnet.ibm.com> + * Copyright 2014 IBM Corporation. + */ + +#define pr_fmt(fmt) "hv-gpci: " fmt + +#include <linux/init.h> +#include <linux/perf_event.h> +#include <asm/firmware.h> +#include <asm/hvcall.h> +#include <asm/io.h> + +#include "hv-gpci.h" +#include "hv-common.h" + +/* + * Example usage: + * perf stat -e 'hv_gpci/counter_info_version=3,offset=0,length=8, + * secondary_index=0,starting_index=0xffffffff,request=0x10/' ... + */ + +/* u32 */ +EVENT_DEFINE_RANGE_FORMAT(request, config, 0, 31); +/* u32 */ +/* + * Note that starting_index, phys_processor_idx, sibling_part_id, + * hw_chip_id, partition_id all refer to the same bit range. They + * are basically aliases for the starting_index. The specific alias + * used depends on the event. See REQUEST_IDX_KIND in hv-gpci-requests.h + */ +EVENT_DEFINE_RANGE_FORMAT(starting_index, config, 32, 63); +EVENT_DEFINE_RANGE_FORMAT_LITE(phys_processor_idx, config, 32, 63); +EVENT_DEFINE_RANGE_FORMAT_LITE(sibling_part_id, config, 32, 63); +EVENT_DEFINE_RANGE_FORMAT_LITE(hw_chip_id, config, 32, 63); +EVENT_DEFINE_RANGE_FORMAT_LITE(partition_id, config, 32, 63); + +/* u16 */ +EVENT_DEFINE_RANGE_FORMAT(secondary_index, config1, 0, 15); +/* u8 */ +EVENT_DEFINE_RANGE_FORMAT(counter_info_version, config1, 16, 23); +/* u8, bytes of data (1-8) */ +EVENT_DEFINE_RANGE_FORMAT(length, config1, 24, 31); +/* u32, byte offset */ +EVENT_DEFINE_RANGE_FORMAT(offset, config1, 32, 63); + +static cpumask_t hv_gpci_cpumask; + +static struct attribute *format_attrs[] = { + &format_attr_request.attr, + &format_attr_starting_index.attr, + &format_attr_phys_processor_idx.attr, + &format_attr_sibling_part_id.attr, + &format_attr_hw_chip_id.attr, + &format_attr_partition_id.attr, + &format_attr_secondary_index.attr, + &format_attr_counter_info_version.attr, + + &format_attr_offset.attr, + &format_attr_length.attr, + NULL, +}; + +static struct attribute_group format_group = { + .name = "format", + .attrs = format_attrs, +}; + +static struct attribute_group event_group = { + .name = "events", + /* .attrs is set in init */ +}; + +#define HV_CAPS_ATTR(_name, _format) \ +static ssize_t _name##_show(struct device *dev, \ + struct device_attribute *attr, \ + char *page) \ +{ \ + struct hv_perf_caps caps; \ + unsigned long hret = hv_perf_caps_get(&caps); \ + if (hret) \ + return -EIO; \ + \ + return sprintf(page, _format, caps._name); \ +} \ +static struct device_attribute hv_caps_attr_##_name = __ATTR_RO(_name) + +static ssize_t kernel_version_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + return sprintf(page, "0x%x\n", COUNTER_INFO_VERSION_CURRENT); +} + +static ssize_t cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return cpumap_print_to_pagebuf(true, buf, &hv_gpci_cpumask); +} + +static DEVICE_ATTR_RO(kernel_version); +static DEVICE_ATTR_RO(cpumask); + +HV_CAPS_ATTR(version, "0x%x\n"); +HV_CAPS_ATTR(ga, "%d\n"); +HV_CAPS_ATTR(expanded, "%d\n"); +HV_CAPS_ATTR(lab, "%d\n"); +HV_CAPS_ATTR(collect_privileged, "%d\n"); + +static struct attribute *interface_attrs[] = { + &dev_attr_kernel_version.attr, + &hv_caps_attr_version.attr, + &hv_caps_attr_ga.attr, + &hv_caps_attr_expanded.attr, + &hv_caps_attr_lab.attr, + &hv_caps_attr_collect_privileged.attr, + NULL, +}; + +static struct attribute *cpumask_attrs[] = { + &dev_attr_cpumask.attr, + NULL, +}; + +static struct attribute_group cpumask_attr_group = { + .attrs = cpumask_attrs, +}; + +static struct attribute_group interface_group = { + .name = "interface", + .attrs = interface_attrs, +}; + +static const struct attribute_group *attr_groups[] = { + &format_group, + &event_group, + &interface_group, + &cpumask_attr_group, + NULL, +}; + +static DEFINE_PER_CPU(char, hv_gpci_reqb[HGPCI_REQ_BUFFER_SIZE]) __aligned(sizeof(uint64_t)); + +static unsigned long single_gpci_request(u32 req, u32 starting_index, + u16 secondary_index, u8 version_in, u32 offset, u8 length, + u64 *value) +{ + unsigned long ret; + size_t i; + u64 count; + struct hv_gpci_request_buffer *arg; + + arg = (void *)get_cpu_var(hv_gpci_reqb); + memset(arg, 0, HGPCI_REQ_BUFFER_SIZE); + + arg->params.counter_request = cpu_to_be32(req); + arg->params.starting_index = cpu_to_be32(starting_index); + arg->params.secondary_index = cpu_to_be16(secondary_index); + arg->params.counter_info_version_in = version_in; + + ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO, + virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE); + if (ret) { + pr_devel("hcall failed: 0x%lx\n", ret); + goto out; + } + + /* + * we verify offset and length are within the zeroed buffer at event + * init. + */ + count = 0; + for (i = offset; i < offset + length; i++) + count |= (u64)(arg->bytes[i]) << ((length - 1 - (i - offset)) * 8); + + *value = count; +out: + put_cpu_var(hv_gpci_reqb); + return ret; +} + +static u64 h_gpci_get_value(struct perf_event *event) +{ + u64 count; + unsigned long ret = single_gpci_request(event_get_request(event), + event_get_starting_index(event), + event_get_secondary_index(event), + event_get_counter_info_version(event), + event_get_offset(event), + event_get_length(event), + &count); + if (ret) + return 0; + return count; +} + +static void h_gpci_event_update(struct perf_event *event) +{ + s64 prev; + u64 now = h_gpci_get_value(event); + prev = local64_xchg(&event->hw.prev_count, now); + local64_add(now - prev, &event->count); +} + +static void h_gpci_event_start(struct perf_event *event, int flags) +{ + local64_set(&event->hw.prev_count, h_gpci_get_value(event)); +} + +static void h_gpci_event_stop(struct perf_event *event, int flags) +{ + h_gpci_event_update(event); +} + +static int h_gpci_event_add(struct perf_event *event, int flags) +{ + if (flags & PERF_EF_START) + h_gpci_event_start(event, flags); + + return 0; +} + +static int h_gpci_event_init(struct perf_event *event) +{ + u64 count; + u8 length; + + /* Not our event */ + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* config2 is unused */ + if (event->attr.config2) { + pr_devel("config2 set when reserved\n"); + return -EINVAL; + } + + /* no branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + + length = event_get_length(event); + if (length < 1 || length > 8) { + pr_devel("length invalid\n"); + return -EINVAL; + } + + /* last byte within the buffer? */ + if ((event_get_offset(event) + length) > HGPCI_MAX_DATA_BYTES) { + pr_devel("request outside of buffer: %zu > %zu\n", + (size_t)event_get_offset(event) + length, + HGPCI_MAX_DATA_BYTES); + return -EINVAL; + } + + /* check if the request works... */ + if (single_gpci_request(event_get_request(event), + event_get_starting_index(event), + event_get_secondary_index(event), + event_get_counter_info_version(event), + event_get_offset(event), + length, + &count)) { + pr_devel("gpci hcall failed\n"); + return -EINVAL; + } + + return 0; +} + +static struct pmu h_gpci_pmu = { + .task_ctx_nr = perf_invalid_context, + + .name = "hv_gpci", + .attr_groups = attr_groups, + .event_init = h_gpci_event_init, + .add = h_gpci_event_add, + .del = h_gpci_event_stop, + .start = h_gpci_event_start, + .stop = h_gpci_event_stop, + .read = h_gpci_event_update, + .capabilities = PERF_PMU_CAP_NO_EXCLUDE, +}; + +static int ppc_hv_gpci_cpu_online(unsigned int cpu) +{ + if (cpumask_empty(&hv_gpci_cpumask)) + cpumask_set_cpu(cpu, &hv_gpci_cpumask); + + return 0; +} + +static int ppc_hv_gpci_cpu_offline(unsigned int cpu) +{ + int target; + + /* Check if exiting cpu is used for collecting gpci events */ + if (!cpumask_test_and_clear_cpu(cpu, &hv_gpci_cpumask)) + return 0; + + /* Find a new cpu to collect gpci events */ + target = cpumask_last(cpu_active_mask); + + if (target < 0 || target >= nr_cpu_ids) { + pr_err("hv_gpci: CPU hotplug init failed\n"); + return -1; + } + + /* Migrate gpci events to the new target */ + cpumask_set_cpu(target, &hv_gpci_cpumask); + perf_pmu_migrate_context(&h_gpci_pmu, cpu, target); + + return 0; +} + +static int hv_gpci_cpu_hotplug_init(void) +{ + return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE, + "perf/powerpc/hv_gcpi:online", + ppc_hv_gpci_cpu_online, + ppc_hv_gpci_cpu_offline); +} + +static int hv_gpci_init(void) +{ + int r; + unsigned long hret; + struct hv_perf_caps caps; + struct hv_gpci_request_buffer *arg; + + hv_gpci_assert_offsets_correct(); + + if (!firmware_has_feature(FW_FEATURE_LPAR)) { + pr_debug("not a virtualized system, not enabling\n"); + return -ENODEV; + } + + hret = hv_perf_caps_get(&caps); + if (hret) { + pr_debug("could not obtain capabilities, not enabling, rc=%ld\n", + hret); + return -ENODEV; + } + + /* init cpuhotplug */ + r = hv_gpci_cpu_hotplug_init(); + if (r) + return r; + + /* sampling not supported */ + h_gpci_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; + + arg = (void *)get_cpu_var(hv_gpci_reqb); + memset(arg, 0, HGPCI_REQ_BUFFER_SIZE); + + /* + * hcall H_GET_PERF_COUNTER_INFO populates the output + * counter_info_version value based on the system hypervisor. + * Pass the counter request 0x10 corresponds to request type + * 'Dispatch_timebase_by_processor', to get the supported + * counter_info_version. + */ + arg->params.counter_request = cpu_to_be32(0x10); + + r = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO, + virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE); + if (r) { + pr_devel("hcall failed, can't get supported counter_info_version: 0x%x\n", r); + arg->params.counter_info_version_out = 0x8; + } + + /* + * Use counter_info_version_out value to assign + * required hv-gpci event list. + */ + if (arg->params.counter_info_version_out >= 0x8) + event_group.attrs = hv_gpci_event_attrs; + else + event_group.attrs = hv_gpci_event_attrs_v6; + + put_cpu_var(hv_gpci_reqb); + + r = perf_pmu_register(&h_gpci_pmu, h_gpci_pmu.name, -1); + if (r) + return r; + + return 0; +} + +device_initcall(hv_gpci_init); |