Re: [PATCH v5 1/6] perf cpumap: Switch to using perf_cpu_map API

From: Arnaldo Carvalho de Melo
Date: Thu May 05 2022 - 13:39:36 EST


Em Wed, May 04, 2022 at 10:44:42AM -0700, Namhyung Kim escreveu:
> Hi Ian,
>
> On Mon, May 2, 2022 at 9:18 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
> >
> > Switch some raw accesses to the cpu map to using the library API. This
> > can help with reference count checking. Some BPF cases switch from index
> > to CPU for consistency, this shouldn't matter as the CPU map is full.
> >
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
>
> Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks, applied.

- Arnaldo


> Thanks,
> Namhyung
>
>
> > ---
> > tools/perf/builtin-record.c | 13 +++++----
> > tools/perf/util/bpf_counter_cgroup.c | 42 +++++++++++++---------------
> > 2 files changed, 26 insertions(+), 29 deletions(-)
> >
> > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> > index 069825c48d40..a5cf6a99d67f 100644
> > --- a/tools/perf/builtin-record.c
> > +++ b/tools/perf/builtin-record.c
> > @@ -1011,7 +1011,7 @@ static int record__thread_data_init_maps(struct record_thread *thread_data, stru
> >
> > for (m = 0, tm = 0; m < nr_mmaps && tm < thread_data->nr_mmaps; m++) {
> > if (cpu_map__is_dummy(cpus) ||
> > - test_bit(cpus->map[m].cpu, thread_data->mask->maps.bits)) {
> > + test_bit(perf_cpu_map__cpu(cpus, m).cpu, thread_data->mask->maps.bits)) {
> > if (thread_data->maps) {
> > thread_data->maps[tm] = &mmap[m];
> > pr_debug2("thread_data[%p]: cpu%d: maps[%d] -> mmap[%d]\n",
> > @@ -3331,13 +3331,14 @@ struct option *record_options = __record_options;
> >
> > static void record__mmap_cpu_mask_init(struct mmap_cpu_mask *mask, struct perf_cpu_map *cpus)
> > {
> > - int c;
> > + struct perf_cpu cpu;
> > + int idx;
> >
> > if (cpu_map__is_dummy(cpus))
> > return;
> >
> > - for (c = 0; c < cpus->nr; c++)
> > - set_bit(cpus->map[c].cpu, mask->bits);
> > + perf_cpu_map__for_each_cpu(cpu, idx, cpus)
> > + set_bit(cpu.cpu, mask->bits);
> > }
> >
> > static int record__mmap_cpu_mask_init_spec(struct mmap_cpu_mask *mask, const char *mask_spec)
> > @@ -3404,8 +3405,8 @@ static int record__init_thread_cpu_masks(struct record *rec, struct perf_cpu_map
> > pr_debug("nr_threads: %d\n", rec->nr_threads);
> >
> > for (t = 0; t < rec->nr_threads; t++) {
> > - set_bit(cpus->map[t].cpu, rec->thread_masks[t].maps.bits);
> > - set_bit(cpus->map[t].cpu, rec->thread_masks[t].affinity.bits);
> > + set_bit(perf_cpu_map__cpu(cpus, t).cpu, rec->thread_masks[t].maps.bits);
> > + set_bit(perf_cpu_map__cpu(cpus, t).cpu, rec->thread_masks[t].affinity.bits);
> > if (verbose) {
> > pr_debug("thread_masks[%d]: ", t);
> > mmap_cpu_mask__scnprintf(&rec->thread_masks[t].maps, "maps");
> > diff --git a/tools/perf/util/bpf_counter_cgroup.c b/tools/perf/util/bpf_counter_cgroup.c
> > index ac60c08e8e2a..63b9db657442 100644
> > --- a/tools/perf/util/bpf_counter_cgroup.c
> > +++ b/tools/perf/util/bpf_counter_cgroup.c
> > @@ -46,8 +46,8 @@ static int bperf_load_program(struct evlist *evlist)
> > struct bpf_link *link;
> > struct evsel *evsel;
> > struct cgroup *cgrp, *leader_cgrp;
> > - __u32 i, cpu;
> > - __u32 nr_cpus = evlist->core.all_cpus->nr;
> > + int i, j;
> > + struct perf_cpu cpu;
> > int total_cpus = cpu__max_cpu().cpu;
> > int map_size, map_fd;
> > int prog_fd, err;
> > @@ -93,9 +93,9 @@ static int bperf_load_program(struct evlist *evlist)
> > goto out;
> > }
> >
> > - for (i = 0; i < nr_cpus; i++) {
> > + 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));
> > + FD(cgrp_switch, cpu.cpu));
> > if (IS_ERR(link)) {
> > pr_err("Failed to attach cgroup program\n");
> > err = PTR_ERR(link);
> > @@ -122,10 +122,9 @@ static int bperf_load_program(struct evlist *evlist)
> > }
> >
> > map_fd = bpf_map__fd(skel->maps.events);
> > - for (cpu = 0; cpu < nr_cpus; cpu++) {
> > - int fd = FD(evsel, cpu);
> > - __u32 idx = evsel->core.idx * total_cpus +
> > - evlist->core.all_cpus->map[cpu].cpu;
> > + perf_cpu_map__for_each_cpu(cpu, j, evlist->core.all_cpus) {
> > + int fd = FD(evsel, cpu.cpu);
> > + __u32 idx = evsel->core.idx * total_cpus + cpu.cpu;
> >
> > err = bpf_map_update_elem(map_fd, &idx, &fd,
> > BPF_ANY);
> > @@ -207,14 +206,12 @@ static int bperf_cgrp__install_pe(struct evsel *evsel __maybe_unused,
> > */
> > static int bperf_cgrp__sync_counters(struct evlist *evlist)
> > {
> > - int i, cpu;
> > - int nr_cpus = evlist->core.all_cpus->nr;
> > + struct perf_cpu cpu;
> > + int idx;
> > int prog_fd = bpf_program__fd(skel->progs.trigger_read);
> >
> > - for (i = 0; i < nr_cpus; i++) {
> > - cpu = evlist->core.all_cpus->map[i].cpu;
> > - bperf_trigger_reading(prog_fd, cpu);
> > - }
> > + perf_cpu_map__for_each_cpu(cpu, idx, evlist->core.all_cpus)
> > + bperf_trigger_reading(prog_fd, cpu.cpu);
> >
> > return 0;
> > }
> > @@ -244,12 +241,10 @@ static int bperf_cgrp__disable(struct evsel *evsel)
> > static int bperf_cgrp__read(struct evsel *evsel)
> > {
> > struct evlist *evlist = evsel->evlist;
> > - int i, cpu, nr_cpus = evlist->core.all_cpus->nr;
> > int total_cpus = cpu__max_cpu().cpu;
> > struct perf_counts_values *counts;
> > struct bpf_perf_event_value *values;
> > int reading_map_fd, err = 0;
> > - __u32 idx;
> >
> > if (evsel->core.idx)
> > return 0;
> > @@ -263,7 +258,10 @@ static int bperf_cgrp__read(struct evsel *evsel)
> > reading_map_fd = bpf_map__fd(skel->maps.cgrp_readings);
> >
> > evlist__for_each_entry(evlist, evsel) {
> > - idx = evsel->core.idx;
> > + __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",
> > @@ -271,13 +269,11 @@ static int bperf_cgrp__read(struct evsel *evsel)
> > goto out;
> > }
> >
> > - for (i = 0; i < nr_cpus; i++) {
> > - cpu = evlist->core.all_cpus->map[i].cpu;
> > -
> > + perf_cpu_map__for_each_cpu(cpu, i, evlist->core.all_cpus) {
> > counts = perf_counts(evsel->counts, i, 0);
> > - counts->val = values[cpu].counter;
> > - counts->ena = values[cpu].enabled;
> > - counts->run = values[cpu].running;
> > + counts->val = values[cpu.cpu].counter;
> > + counts->ena = values[cpu.cpu].enabled;
> > + counts->run = values[cpu.cpu].running;
> > }
> > }
> >
> > --
> > 2.36.0.464.gb9c8b46e94-goog
> >

--

- Arnaldo