Re: [PATCH v2 0/7] Copy hashmap to tools/perf/util, use in perf expr

[Andrii Nakryiko]

On Fri, May 15, 2020 at 10:01 AM Arnaldo Carvalho de Melo
<arnaldo.melo@xxxxxxxxx> wrote:
>
> Em Fri, May 15, 2020 at 09:50:00AM -0700, Ian Rogers escreveu:
> > Perf's expr code currently builds an array of strings then removes
> > duplicates. The array is larger than necessary and has recently been
> > increased in size. When this was done it was commented that a hashmap
> > would be preferable.
> >
> > libbpf has a hashmap but libbpf isn't currently required to build
> > perf. To satisfy various concerns this change copies libbpf's hashmap
> > into tools/perf/util, it then adds a check in perf that the two are in
> > sync.
> >
> > Andrii's patch to hashmap from bpf-next is brought into this set to
> > fix issues with hashmap__clear.
> >
> > Two minor changes to libbpf's hashmap are made that remove an unused
> > dependency and fix a compiler warning.
>
> Andrii/Alexei/Daniel, what do you think about me merging these fixes in my
> perf-tools-next branch?

I'm ok with the idea, but it's up to maintainers to coordinate this :)

>
> - Arnaldo
>
> > Two perf test changes are also brought in as they need refactoring to
> > account for the expr API change and it is expected they will land
> > ahead of this.
> > https://lore.kernel.org/lkml/20200513062236.854-2-irogers@xxxxxxxxxx/
> >
> > Tested with 'perf test' and 'make -C tools/perf build-test'.
> >
> > The hashmap change was originally part of an RFC:
> > https://lore.kernel.org/lkml/20200508053629.210324-1-irogers@xxxxxxxxxx/
> >
> > v2. moves hashmap into tools/perf/util rather than libapi, to allow
> > hashmap's libbpf symbols to be visible when built statically for
> > testing.
> >
> > Andrii Nakryiko (1):
> >   libbpf: Fix memory leak and possible double-free in hashmap__clear
> >
> > Ian Rogers (6):
> >   libbpf hashmap: Remove unused #include
> >   libbpf hashmap: Fix signedness warnings
> >   tools lib/api: Copy libbpf hashmap to tools/perf/util
> >   perf test: Provide a subtest callback to ask for the reason for
> >     skipping a subtest
> >   perf test: Improve pmu event metric testing
> >   perf expr: Migrate expr ids table to a hashmap
> >
> >  tools/lib/bpf/hashmap.c         |  10 +-
> >  tools/lib/bpf/hashmap.h         |   1 -
> >  tools/perf/check-headers.sh     |   4 +
> >  tools/perf/tests/builtin-test.c |  18 ++-
> >  tools/perf/tests/expr.c         |  40 +++---
> >  tools/perf/tests/pmu-events.c   | 169 ++++++++++++++++++++++-
> >  tools/perf/tests/tests.h        |   4 +
> >  tools/perf/util/Build           |   4 +
> >  tools/perf/util/expr.c          | 129 +++++++++--------
> >  tools/perf/util/expr.h          |  26 ++--
> >  tools/perf/util/expr.y          |  22 +--
> >  tools/perf/util/hashmap.c       | 238 ++++++++++++++++++++++++++++++++
> >  tools/perf/util/hashmap.h       | 177 ++++++++++++++++++++++++
> >  tools/perf/util/metricgroup.c   |  87 ++++++------
> >  tools/perf/util/stat-shadow.c   |  49 ++++---
> >  15 files changed, 798 insertions(+), 180 deletions(-)
> >  create mode 100644 tools/perf/util/hashmap.c
> >  create mode 100644 tools/perf/util/hashmap.h
> >
> > --
> > 2.26.2.761.g0e0b3e54be-goog
> >
>
> --
>
> - Arnaldo