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

From: Arnaldo Carvalho de Melo <[email-masked]>
Date: Fri, 15 May 2020 14:00:36 -0300

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/[email-masked]/
> 
> 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/[email-masked]/
> 
> 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