diff options
Diffstat (limited to 'tools/perf/util/bpf_kwork_top.c')
| -rw-r--r-- | tools/perf/util/bpf_kwork_top.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/tools/perf/util/bpf_kwork_top.c b/tools/perf/util/bpf_kwork_top.c new file mode 100644 index 000000000000..42897ea22c61 --- /dev/null +++ b/tools/perf/util/bpf_kwork_top.c @@ -0,0 +1,286 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * bpf_kwork_top.c + * + * Copyright (c) 2022 Huawei Inc, Yang Jihong <yangjihong1@huawei.com> + */ + +#include <time.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <unistd.h> + +#include <linux/time64.h> + +#include "util/debug.h" +#include "util/evsel.h" +#include "util/kwork.h" + +#include <bpf/bpf.h> +#include <perf/cpumap.h> + +#include "util/bpf_skel/kwork_top.skel.h" + +/* + * This should be in sync with "util/kwork_top.bpf.c" + */ +#define MAX_COMMAND_LEN 16 + +struct time_data { + __u64 timestamp; +}; + +struct work_data { + __u64 runtime; +}; + +struct task_data { + __u32 tgid; + __u32 is_kthread; + char comm[MAX_COMMAND_LEN]; +}; + +struct work_key { + __u32 type; + __u32 pid; + __u64 task_p; +}; + +struct task_key { + __u32 pid; + __u32 cpu; +}; + +struct kwork_class_bpf { + struct kwork_class *class; + void (*load_prepare)(void); +}; + +static struct kwork_top_bpf *skel; + +void perf_kwork__top_start(void) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC, &ts); + skel->bss->from_timestamp = (u64)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec; + skel->bss->enabled = 1; + pr_debug("perf kwork top start at: %lld\n", skel->bss->from_timestamp); +} + +void perf_kwork__top_finish(void) +{ + struct timespec ts; + + skel->bss->enabled = 0; + clock_gettime(CLOCK_MONOTONIC, &ts); + skel->bss->to_timestamp = (u64)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec; + pr_debug("perf kwork top finish at: %lld\n", skel->bss->to_timestamp); +} + +static void sched_load_prepare(void) +{ + bpf_program__set_autoload(skel->progs.on_switch, true); +} + +static struct kwork_class_bpf kwork_sched_bpf = { + .load_prepare = sched_load_prepare, +}; + +static struct kwork_class_bpf * +kwork_class_bpf_supported_list[KWORK_CLASS_MAX] = { + [KWORK_CLASS_SCHED] = &kwork_sched_bpf, +}; + +static bool valid_kwork_class_type(enum kwork_class_type type) +{ + return type >= 0 && type < KWORK_CLASS_MAX ? true : false; +} + +static int setup_filters(struct perf_kwork *kwork) +{ + u8 val = 1; + int i, nr_cpus, fd; + struct perf_cpu_map *map; + + if (kwork->cpu_list) { + fd = bpf_map__fd(skel->maps.kwork_top_cpu_filter); + if (fd < 0) { + pr_debug("Invalid cpu filter fd\n"); + return -1; + } + + map = perf_cpu_map__new(kwork->cpu_list); + if (!map) { + pr_debug("Invalid cpu_list\n"); + return -1; + } + + nr_cpus = libbpf_num_possible_cpus(); + for (i = 0; i < perf_cpu_map__nr(map); i++) { + struct perf_cpu cpu = perf_cpu_map__cpu(map, i); + + if (cpu.cpu >= nr_cpus) { + perf_cpu_map__put(map); + pr_err("Requested cpu %d too large\n", cpu.cpu); + return -1; + } + bpf_map_update_elem(fd, &cpu.cpu, &val, BPF_ANY); + } + perf_cpu_map__put(map); + + skel->bss->has_cpu_filter = 1; + } + + return 0; +} + +int perf_kwork__top_prepare_bpf(struct perf_kwork *kwork __maybe_unused) +{ + struct bpf_program *prog; + struct kwork_class *class; + struct kwork_class_bpf *class_bpf; + enum kwork_class_type type; + + skel = kwork_top_bpf__open(); + if (!skel) { + pr_debug("Failed to open kwork top skeleton\n"); + return -1; + } + + /* + * set all progs to non-autoload, + * then set corresponding progs according to config + */ + bpf_object__for_each_program(prog, skel->obj) + bpf_program__set_autoload(prog, false); + + list_for_each_entry(class, &kwork->class_list, list) { + type = class->type; + if (!valid_kwork_class_type(type) || + !kwork_class_bpf_supported_list[type]) { + pr_err("Unsupported bpf trace class %s\n", class->name); + goto out; + } + + class_bpf = kwork_class_bpf_supported_list[type]; + class_bpf->class = class; + + if (class_bpf->load_prepare) + class_bpf->load_prepare(); + } + + if (kwork_top_bpf__load(skel)) { + pr_debug("Failed to load kwork top skeleton\n"); + goto out; + } + + if (setup_filters(kwork)) + goto out; + + if (kwork_top_bpf__attach(skel)) { + pr_debug("Failed to attach kwork top skeleton\n"); + goto out; + } + + return 0; + +out: + kwork_top_bpf__destroy(skel); + return -1; +} + +static void read_task_info(struct kwork_work *work) +{ + int fd; + struct task_data data; + struct task_key key = { + .pid = work->id, + .cpu = work->cpu, + }; + + fd = bpf_map__fd(skel->maps.kwork_top_tasks); + if (fd < 0) { + pr_debug("Invalid top tasks map fd\n"); + return; + } + + if (!bpf_map_lookup_elem(fd, &key, &data)) { + work->tgid = data.tgid; + work->is_kthread = data.is_kthread; + work->name = strdup(data.comm); + } +} +static int add_work(struct perf_kwork *kwork, struct work_key *key, + struct work_data *data, int cpu) +{ + struct kwork_class_bpf *bpf_trace; + struct kwork_work *work; + struct kwork_work tmp = { + .id = key->pid, + .cpu = cpu, + .name = NULL, + }; + enum kwork_class_type type = key->type; + + if (!valid_kwork_class_type(type)) { + pr_debug("Invalid class type %d to add work\n", type); + return -1; + } + + bpf_trace = kwork_class_bpf_supported_list[type]; + tmp.class = bpf_trace->class; + + work = perf_kwork_add_work(kwork, tmp.class, &tmp); + if (!work) + return -1; + + work->total_runtime = data->runtime; + read_task_info(work); + + return 0; +} + +int perf_kwork__top_read_bpf(struct perf_kwork *kwork) +{ + int i, fd, nr_cpus; + struct work_data *data; + struct work_key key, prev; + + fd = bpf_map__fd(skel->maps.kwork_top_works); + if (fd < 0) { + pr_debug("Invalid top runtime fd\n"); + return -1; + } + + nr_cpus = libbpf_num_possible_cpus(); + data = calloc(nr_cpus, sizeof(struct work_data)); + if (!data) + return -1; + + memset(&prev, 0, sizeof(prev)); + while (!bpf_map_get_next_key(fd, &prev, &key)) { + if ((bpf_map_lookup_elem(fd, &key, data)) != 0) { + pr_debug("Failed to lookup top elem\n"); + return -1; + } + + for (i = 0; i < nr_cpus; i++) { + if (data[i].runtime == 0) + continue; + + if (add_work(kwork, &key, &data[i], i)) + return -1; + } + prev = key; + } + free(data); + + return 0; +} + +void perf_kwork__top_cleanup_bpf(void) +{ + kwork_top_bpf__destroy(skel); +} |