Re: [PATCH v4 02/48] perf stat: Add aggr creators that are passed a cpu.

From: Ian Rogers
Date: Tue Jan 11 2022 - 14:36:18 EST


On Tue, Jan 11, 2022 at 11:33 AM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Tue, Jan 04, 2022 at 10:13:05PM -0800, Ian Rogers escreveu:
> > The cpu_map and index can get confused. Add variants of the cpu_map__get
> > routines that are passed a cpu. Make the existing cpu_map__get routines
> > use the new functions with a view to remove them when no longer used.
> >
> > Reviewed-by: James Clark <james.clark@xxxxxxx>
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
> > tools/perf/util/cpumap.c | 79 +++++++++++++++++++++++-----------------
> > tools/perf/util/cpumap.h | 6 ++-
> > 2 files changed, 51 insertions(+), 34 deletions(-)
> >
> > diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c
> > index 87d3eca9b872..49fba2c53822 100644
> > --- a/tools/perf/util/cpumap.c
> > +++ b/tools/perf/util/cpumap.c
> > @@ -128,21 +128,23 @@ int cpu_map__get_socket_id(int cpu)
> > return ret ?: value;
> > }
> >
> > -struct aggr_cpu_id cpu_map__get_socket(struct perf_cpu_map *map, int idx,
> > - void *data __maybe_unused)
> > +struct aggr_cpu_id cpu_map__get_socket_aggr_by_cpu(int cpu, void *data __maybe_unused)
> > {
> > - int cpu;
> > struct aggr_cpu_id id = cpu_map__empty_aggr_cpu_id();
> >
> > - if (idx > map->nr)
> > - return id;
> > -
> > - cpu = map->map[idx];
> > -
> > id.socket = cpu_map__get_socket_id(cpu);
> > return id;
> > }
> >
> > +struct aggr_cpu_id cpu_map__get_socket(struct perf_cpu_map *map, int idx,
> > + void *data)
> > +{
> > + if (idx < 0 || idx > map->nr)
> > + return cpu_map__empty_aggr_cpu_id();
> > +
> > + return cpu_map__get_socket_aggr_by_cpu(map->map[idx], data);
> > +}
> > +
>
>
> This 'idx < 0' wasn't in the original code nor is described in the
> comment log message, please avoid doing this, this may be harmless or
> even a good hardening, but either way would be interesting to have it in
> a separate patch. This eases review as in the end this code is just a
> refactoring, moving things around but in the end should be equivalent code.
>
> There are a few more, please consider this and if you agree, to speed
> things up I can make the changes here, if I think this won't fallout in
> changes to subsequent patches touching this area.
>
> - Arnaldo

Fwiw, there's the same issue in cpu_map__get_die that's also in
cpu_map__get_core, but weirdly not copied into cpu_map__get_node. As
these functions are removed later I think doing nothing is best here.

Thanks,
Ian

> > static int cmp_aggr_cpu_id(const void *a_pointer, const void *b_pointer)
> > {
> > struct aggr_cpu_id *a = (struct aggr_cpu_id *)a_pointer;
> > @@ -200,15 +202,10 @@ int cpu_map__get_die_id(int cpu)
> > return ret ?: value;
> > }
> >
> > -struct aggr_cpu_id cpu_map__get_die(struct perf_cpu_map *map, int idx, void *data)
> > +struct aggr_cpu_id cpu_map__get_die_aggr_by_cpu(int cpu, void *data)
> > {
> > - int cpu, die;
> > - struct aggr_cpu_id id = cpu_map__empty_aggr_cpu_id();
> > -
> > - if (idx > map->nr)
> > - return id;
> > -
> > - cpu = map->map[idx];
> > + struct aggr_cpu_id id;
> > + int die;
> >
> > die = cpu_map__get_die_id(cpu);
> > /* There is no die_id on legacy system. */
> > @@ -220,7 +217,7 @@ struct aggr_cpu_id cpu_map__get_die(struct perf_cpu_map *map, int idx, void *dat
> > * with the socket ID and then add die to
> > * make a unique ID.
> > */
> > - id = cpu_map__get_socket(map, idx, data);
> > + id = cpu_map__get_socket_aggr_by_cpu(cpu, data);
> > if (cpu_map__aggr_cpu_id_is_empty(id))
> > return id;
> >
> > @@ -228,6 +225,15 @@ struct aggr_cpu_id cpu_map__get_die(struct perf_cpu_map *map, int idx, void *dat
> > return id;
> > }
> >
> > +struct aggr_cpu_id cpu_map__get_die(struct perf_cpu_map *map, int idx,
> > + void *data)
> > +{
> > + if (idx < 0 || idx > map->nr)
> > + return cpu_map__empty_aggr_cpu_id();
>
> Ditto
>
> > +
> > + return cpu_map__get_die_aggr_by_cpu(map->map[idx], data);
> > +}
> > +
> > int cpu_map__get_core_id(int cpu)
> > {
> > int value, ret = cpu__get_topology_int(cpu, "core_id", &value);
> > @@ -239,20 +245,13 @@ int cpu_map__get_node_id(int cpu)
> > return cpu__get_node(cpu);
> > }
> >
> > -struct aggr_cpu_id cpu_map__get_core(struct perf_cpu_map *map, int idx, void *data)
> > +struct aggr_cpu_id cpu_map__get_core_aggr_by_cpu(int cpu, void *data)
> > {
> > - int cpu;
> > - struct aggr_cpu_id id = cpu_map__empty_aggr_cpu_id();
> > -
> > - if (idx > map->nr)
> > - return id;
> > -
> > - cpu = map->map[idx];
> > -
> > - cpu = cpu_map__get_core_id(cpu);
> > + struct aggr_cpu_id id;
> > + int core = cpu_map__get_core_id(cpu);
> >
> > /* cpu_map__get_die returns a struct with socket and die set*/
> > - id = cpu_map__get_die(map, idx, data);
> > + id = cpu_map__get_die_aggr_by_cpu(cpu, data);
> > if (cpu_map__aggr_cpu_id_is_empty(id))
> > return id;
> >
> > @@ -260,19 +259,33 @@ struct aggr_cpu_id cpu_map__get_core(struct perf_cpu_map *map, int idx, void *da
> > * core_id is relative to socket and die, we need a global id.
> > * So we combine the result from cpu_map__get_die with the core id
> > */
> > - id.core = cpu;
> > + id.core = core;
> > return id;
> > +
> > }
> >
> > -struct aggr_cpu_id cpu_map__get_node(struct perf_cpu_map *map, int idx, void *data __maybe_unused)
> > +struct aggr_cpu_id cpu_map__get_core(struct perf_cpu_map *map, int idx, void *data)
> > +{
> > + if (idx < 0 || idx > map->nr)
> > + return cpu_map__empty_aggr_cpu_id();
>
> Ditto
>
> > +
> > + return cpu_map__get_core_aggr_by_cpu(map->map[idx], data);
> > +}
> > +
> > +struct aggr_cpu_id cpu_map__get_node_aggr_by_cpu(int cpu, void *data __maybe_unused)
> > {
> > struct aggr_cpu_id id = cpu_map__empty_aggr_cpu_id();
> >
> > + id.node = cpu_map__get_node_id(cpu);
> > + return id;
> > +}
> > +
> > +struct aggr_cpu_id cpu_map__get_node(struct perf_cpu_map *map, int idx, void *data)
> > +{
> > if (idx < 0 || idx >= map->nr)
> > - return id;
> > + return cpu_map__empty_aggr_cpu_id();
> >
> > - id.node = cpu_map__get_node_id(map->map[idx]);
> > - return id;
> > + return cpu_map__get_node_aggr_by_cpu(map->map[idx], data);
> > }
> >
> > int cpu_map__build_socket_map(struct perf_cpu_map *cpus, struct cpu_aggr_map **sockp)
> > diff --git a/tools/perf/util/cpumap.h b/tools/perf/util/cpumap.h
> > index a27eeaf086e8..c62d67704425 100644
> > --- a/tools/perf/util/cpumap.h
> > +++ b/tools/perf/util/cpumap.h
> > @@ -31,13 +31,17 @@ size_t cpu_map__snprint(struct perf_cpu_map *map, char *buf, size_t size);
> > size_t cpu_map__snprint_mask(struct perf_cpu_map *map, char *buf, size_t size);
> > size_t cpu_map__fprintf(struct perf_cpu_map *map, FILE *fp);
> > int cpu_map__get_socket_id(int cpu);
> > +struct aggr_cpu_id cpu_map__get_socket_aggr_by_cpu(int cpu, void *data);
> > struct aggr_cpu_id cpu_map__get_socket(struct perf_cpu_map *map, int idx, void *data);
> > int cpu_map__get_die_id(int cpu);
> > +struct aggr_cpu_id cpu_map__get_die_aggr_by_cpu(int cpu, void *data);
> > struct aggr_cpu_id cpu_map__get_die(struct perf_cpu_map *map, int idx, void *data);
> > int cpu_map__get_core_id(int cpu);
> > +struct aggr_cpu_id cpu_map__get_core_aggr_by_cpu(int cpu, void *data);
> > struct aggr_cpu_id cpu_map__get_core(struct perf_cpu_map *map, int idx, void *data);
> > int cpu_map__get_node_id(int cpu);
> > -struct aggr_cpu_id cpu_map__get_node(struct perf_cpu_map *map, int idx, void *data);
> > +struct aggr_cpu_id cpu_map__get_node_aggr_by_cpu(int cpu, void *data);
> > +struct aggr_cpu_id cpu_map__get_node(struct perf_cpu_map *map, int idx, void *data);
> > int cpu_map__build_socket_map(struct perf_cpu_map *cpus, struct cpu_aggr_map **sockp);
> > int cpu_map__build_die_map(struct perf_cpu_map *cpus, struct cpu_aggr_map **diep);
> > int cpu_map__build_core_map(struct perf_cpu_map *cpus, struct cpu_aggr_map **corep);
> > --
> > 2.34.1.448.ga2b2bfdf31-goog
>
> --
>
> - Arnaldo