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. 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/ v3. addresses review feedback from Andrii Nakryiko <andriin@xxxxxx> and Jiri Olsa <jolsa@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 | 44 +++--- 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 | 92 ++++++------ tools/perf/util/stat-shadow.c | 49 ++++--- 15 files changed, 798 insertions(+), 189 deletions(-) create mode 100644 tools/perf/util/hashmap.c create mode 100644 tools/perf/util/hashmap.h -- 2.26.2.761.g0e0b3e54be-goog
