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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /tools/perf/util/bpf_counter_cgroup.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/perf/util/bpf_counter_cgroup.c')
-rw-r--r-- | tools/perf/util/bpf_counter_cgroup.c | 295 |
1 files changed, 295 insertions, 0 deletions
diff --git a/tools/perf/util/bpf_counter_cgroup.c b/tools/perf/util/bpf_counter_cgroup.c new file mode 100644 index 0000000000..1c82377ed7 --- /dev/null +++ b/tools/perf/util/bpf_counter_cgroup.c @@ -0,0 +1,295 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Copyright (c) 2021 Facebook */ +/* Copyright (c) 2021 Google */ + +#include <assert.h> +#include <limits.h> +#include <unistd.h> +#include <sys/file.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <linux/err.h> +#include <linux/zalloc.h> +#include <linux/perf_event.h> +#include <api/fs/fs.h> +#include <perf/bpf_perf.h> + +#include "affinity.h" +#include "bpf_counter.h" +#include "cgroup.h" +#include "counts.h" +#include "debug.h" +#include "evsel.h" +#include "evlist.h" +#include "target.h" +#include "cpumap.h" +#include "thread_map.h" + +#include "bpf_skel/bperf_cgroup.skel.h" + +static struct perf_event_attr cgrp_switch_attr = { + .type = PERF_TYPE_SOFTWARE, + .config = PERF_COUNT_SW_CGROUP_SWITCHES, + .size = sizeof(cgrp_switch_attr), + .sample_period = 1, + .disabled = 1, +}; + +static struct evsel *cgrp_switch; +static struct bperf_cgroup_bpf *skel; + +#define FD(evt, cpu) (*(int *)xyarray__entry(evt->core.fd, cpu, 0)) + +static int bperf_load_program(struct evlist *evlist) +{ + struct bpf_link *link; + struct evsel *evsel; + struct cgroup *cgrp, *leader_cgrp; + int i, j; + struct perf_cpu cpu; + int total_cpus = cpu__max_cpu().cpu; + int map_size, map_fd; + int prog_fd, err; + + skel = bperf_cgroup_bpf__open(); + if (!skel) { + pr_err("Failed to open cgroup skeleton\n"); + return -1; + } + + skel->rodata->num_cpus = total_cpus; + skel->rodata->num_events = evlist->core.nr_entries / nr_cgroups; + + BUG_ON(evlist->core.nr_entries % nr_cgroups != 0); + + /* we need one copy of events per cpu for reading */ + map_size = total_cpus * evlist->core.nr_entries / nr_cgroups; + bpf_map__set_max_entries(skel->maps.events, map_size); + bpf_map__set_max_entries(skel->maps.cgrp_idx, nr_cgroups); + /* previous result is saved in a per-cpu array */ + map_size = evlist->core.nr_entries / nr_cgroups; + bpf_map__set_max_entries(skel->maps.prev_readings, map_size); + /* cgroup result needs all events (per-cpu) */ + map_size = evlist->core.nr_entries; + bpf_map__set_max_entries(skel->maps.cgrp_readings, map_size); + + set_max_rlimit(); + + err = bperf_cgroup_bpf__load(skel); + if (err) { + pr_err("Failed to load cgroup skeleton\n"); + goto out; + } + + if (cgroup_is_v2("perf_event") > 0) + skel->bss->use_cgroup_v2 = 1; + + err = -1; + + cgrp_switch = evsel__new(&cgrp_switch_attr); + if (evsel__open_per_cpu(cgrp_switch, evlist->core.all_cpus, -1) < 0) { + pr_err("Failed to open cgroup switches event\n"); + goto out; + } + + perf_cpu_map__for_each_cpu(cpu, i, evlist->core.all_cpus) { + link = bpf_program__attach_perf_event(skel->progs.on_cgrp_switch, + FD(cgrp_switch, i)); + if (IS_ERR(link)) { + pr_err("Failed to attach cgroup program\n"); + err = PTR_ERR(link); + goto out; + } + } + + /* + * Update cgrp_idx map from cgroup-id to event index. + */ + cgrp = NULL; + i = 0; + + evlist__for_each_entry(evlist, evsel) { + if (cgrp == NULL || evsel->cgrp == leader_cgrp) { + leader_cgrp = evsel->cgrp; + evsel->cgrp = NULL; + + /* open single copy of the events w/o cgroup */ + err = evsel__open_per_cpu(evsel, evsel->core.cpus, -1); + if (err == 0) + evsel->supported = true; + + map_fd = bpf_map__fd(skel->maps.events); + perf_cpu_map__for_each_cpu(cpu, j, evsel->core.cpus) { + int fd = FD(evsel, j); + __u32 idx = evsel->core.idx * total_cpus + cpu.cpu; + + bpf_map_update_elem(map_fd, &idx, &fd, BPF_ANY); + } + + evsel->cgrp = leader_cgrp; + } + + if (evsel->cgrp == cgrp) + continue; + + cgrp = evsel->cgrp; + + if (read_cgroup_id(cgrp) < 0) { + pr_err("Failed to get cgroup id\n"); + err = -1; + goto out; + } + + map_fd = bpf_map__fd(skel->maps.cgrp_idx); + err = bpf_map_update_elem(map_fd, &cgrp->id, &i, BPF_ANY); + if (err < 0) { + pr_err("Failed to update cgroup index map\n"); + goto out; + } + + i++; + } + + /* + * bperf uses BPF_PROG_TEST_RUN to get accurate reading. Check + * whether the kernel support it + */ + prog_fd = bpf_program__fd(skel->progs.trigger_read); + err = bperf_trigger_reading(prog_fd, 0); + if (err) { + pr_warning("The kernel does not support test_run for raw_tp BPF programs.\n" + "Therefore, --for-each-cgroup might show inaccurate readings\n"); + err = 0; + } + +out: + return err; +} + +static int bperf_cgrp__load(struct evsel *evsel, + struct target *target __maybe_unused) +{ + static bool bperf_loaded = false; + + evsel->bperf_leader_prog_fd = -1; + evsel->bperf_leader_link_fd = -1; + + if (!bperf_loaded && bperf_load_program(evsel->evlist)) + return -1; + + bperf_loaded = true; + /* just to bypass bpf_counter_skip() */ + evsel->follower_skel = (struct bperf_follower_bpf *)skel; + + return 0; +} + +static int bperf_cgrp__install_pe(struct evsel *evsel __maybe_unused, + int cpu __maybe_unused, int fd __maybe_unused) +{ + /* nothing to do */ + return 0; +} + +/* + * trigger the leader prog on each cpu, so the cgrp_reading map could get + * the latest results. + */ +static int bperf_cgrp__sync_counters(struct evlist *evlist) +{ + struct perf_cpu cpu; + int idx; + int prog_fd = bpf_program__fd(skel->progs.trigger_read); + + perf_cpu_map__for_each_cpu(cpu, idx, evlist->core.all_cpus) + bperf_trigger_reading(prog_fd, cpu.cpu); + + return 0; +} + +static int bperf_cgrp__enable(struct evsel *evsel) +{ + if (evsel->core.idx) + return 0; + + bperf_cgrp__sync_counters(evsel->evlist); + + skel->bss->enabled = 1; + return 0; +} + +static int bperf_cgrp__disable(struct evsel *evsel) +{ + if (evsel->core.idx) + return 0; + + bperf_cgrp__sync_counters(evsel->evlist); + + skel->bss->enabled = 0; + return 0; +} + +static int bperf_cgrp__read(struct evsel *evsel) +{ + struct evlist *evlist = evsel->evlist; + int total_cpus = cpu__max_cpu().cpu; + struct perf_counts_values *counts; + struct bpf_perf_event_value *values; + int reading_map_fd, err = 0; + + if (evsel->core.idx) + return 0; + + bperf_cgrp__sync_counters(evsel->evlist); + + values = calloc(total_cpus, sizeof(*values)); + if (values == NULL) + return -ENOMEM; + + reading_map_fd = bpf_map__fd(skel->maps.cgrp_readings); + + evlist__for_each_entry(evlist, evsel) { + __u32 idx = evsel->core.idx; + int i; + struct perf_cpu cpu; + + err = bpf_map_lookup_elem(reading_map_fd, &idx, values); + if (err) { + pr_err("bpf map lookup failed: idx=%u, event=%s, cgrp=%s\n", + idx, evsel__name(evsel), evsel->cgrp->name); + goto out; + } + + perf_cpu_map__for_each_cpu(cpu, i, evsel->core.cpus) { + counts = perf_counts(evsel->counts, i, 0); + counts->val = values[cpu.cpu].counter; + counts->ena = values[cpu.cpu].enabled; + counts->run = values[cpu.cpu].running; + } + } + +out: + free(values); + return err; +} + +static int bperf_cgrp__destroy(struct evsel *evsel) +{ + if (evsel->core.idx) + return 0; + + bperf_cgroup_bpf__destroy(skel); + evsel__delete(cgrp_switch); // it'll destroy on_switch progs too + + return 0; +} + +struct bpf_counter_ops bperf_cgrp_ops = { + .load = bperf_cgrp__load, + .enable = bperf_cgrp__enable, + .disable = bperf_cgrp__disable, + .read = bperf_cgrp__read, + .install_pe = bperf_cgrp__install_pe, + .destroy = bperf_cgrp__destroy, +}; |