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

From: Arnaldo Carvalho de Melo
Date: Fri May 15 2020 - 13:00:42 EST


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?

- 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