Re: [PATCH V3 00/10] perf tools: Fix test "perf probe of function from different CU"

[James Clark <james.clark@linaro.org>]

On 10/07/2024 8:39 am, Chaitanya S Prakash wrote:
> Gentle ping, are there any updates on the string clean up patch set?
> 
> On 6/1/24 18:29, Chaitanya S Prakash wrote:
>> From: Chaitanya S Prakash <chaitanyas.prakash@arm.com>
>>
>> Perf treated all files beginning with "/tmp/perf-" as a map file despite
>> them always ending in ".map", this caused the test "perf probe of
>> function from different CU" to fail when Perf was built with NO_DWARF=1.
>> As the file was parsed as a map file, the probe...--funcs command output
>> garbage values instead of listing the functions in the binary. After
>> fixing the issue an additional check to test the output of the
>> probe...--funcs command has been added.
>>
>> Additionally, various functions within the codebase have been refactored
>> and restructured. The definition of str_has_suffix() has been adopted
>> from tools/bpf/bpftool/gen.c and added to tools/lib/string.c in an
>> attempt to make the function more generic. The implementation has been
>> retained but the return values have been modified to resemble that of
>> str_has_prefix(), i.e., return strlen(suffix) on success and 0 on
>> failure. In light of the new addition, "ends_with()", a locally defined
>> function used for checking if a string had a given suffix has been
>> deleted and str_has_suffix() has replaced its usage. A call to
>> strtailcmp() has also been replaced as str_has_suffix() seemed more
>> suited for that particular use case.
>>
>> Finally str_has_prefix() is adopted from the kernel and is added to
>> tools/lib/string.c, following which strstarts() is deleted and its use
>> has been replaced with str_has_prefix().
>>
>> This patch series has been tested on 6.10-rc1 mainline kernel, both on
>> arm64 and x86 platforms.
>>
>> Changes in V3:
>>
>> - Patch adding configs required by "perf probe of function from different
>>    CU" was originally part of the series but has been merged in 6.10-rc1.
>>    
>> https://github.com/torvalds/linux/commit/6b718ac6874c2233b8dec369a8a377d6c5b638e6
>>
>> - Restructure patches according to the maintainer trees.
>> - Add explanation for why '| grep "foo"' is used.
>> - Fix build errors for when perf is built with LLVM=1.
>>
>> Changes in V2:
>> https://lore.kernel.org/all/20240408062230.1949882-1-ChaitanyaS.Prakash@arm.com/
>>
>> - Add str_has_suffix() and str_has_prefix() to tools/lib/string.c
>> - Delete ends_with() and replace its usage with str_has_suffix()
>> - Replace an instance of strtailcmp() with str_has_suffix()
>> - Delete strstarts() from tools/include/linux/string.h and replace its
>>    usage with str_has_prefix()
>>
>> Changes in V1:
>> https://lore.kernel.org/all/20240220042957.2022391-1-ChaitanyaS.Prakash@arm.com/
>>
>> Cc: Josh Poimboeuf <jpoimboe@kernel.org>
>> Cc: Peter Zijlstra <peterz@infradead.org>
>> Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
>> Cc: Mike Leach <mike.leach@linaro.org>
>> Cc: James Clark <james.clark@arm.com>
>> Cc: John Garry <john.g.garry@oracle.com>
>> Cc: Will Deacon <will@kernel.org>
>> Cc: Leo Yan <leo.yan@linaro.org>
>> Cc: Ingo Molnar <mingo@redhat.com>
>> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
>> Cc: Namhyung Kim <namhyung@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
>> Cc: Jiri Olsa <jolsa@kernel.org>
>> Cc: Ian Rogers <irogers@google.com>
>> Cc: Adrian Hunter <adrian.hunter@intel.com>
>> Cc: Chenyuan Mi <cymi20@fudan.edu.cn>
>> Cc: Masami Hiramatsu <mhiramat@kernel.org>
>> Cc: Ravi Bangoria <ravi.bangoria@amd.com>
>> Cc: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
>> Cc: Colin Ian King <colin.i.king@gmail.com>
>> Cc: Changbin Du <changbin.du@huawei.com>
>> Cc: Kan Liang <kan.liang@linux.intel.com>
>> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>> Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
>> Cc: Alexey Dobriyan <adobriyan@gmail.com>
>> Cc: Georg Müller <georgmueller@gmx.net>
>> Cc: Liam Howlett <liam.howlett@oracle.com>
>> Cc: bpf@vger.kernel.org
>> Cc: coresight@lists.linaro.org
>> Cc: linux-arm-kernel@lists.infradead.org
>> Cc: linux-kernel@vger.kernel.org
>> Cc: linux-perf-users@vger.kernel.org
>>
>> Chaitanya S Prakash (10):
>>    tools lib: adopt str_has_suffix() from bpftool/gen.c

LGTM,

Reviewed-by: James Clark <james.clark@arm.com>

The below commit looked like it could be prone to an off by one error 
but I debugged it to confirm that it's ok:

>>    perf util: Delete ends_with() and replace its use with
>>      str_has_suffix()

>>    perf util: Replace an instance of strtailcmp() by str_has_suffix()
>>    tools lib: Adopt str_has_prefix() from kernel
>>    libsubcmd: Replace strstarts() usage with str_has_prefix()
>>    objtool: Replace strstarts() usage with str_has_prefix()
>>    perf tools: Replace strstarts() usage with str_has_prefix()
>>    tools lib: Remove strstarts() as all its usecases have been replaced
>>      by str_has_prefix()
>>    perf tools: Only treat files as map files when they have the extension
>>      .map
>>    perf test: Check output of the probe ... --funcs command
>>
>>   tools/include/linux/string.h                  | 12 ++---
>>   tools/lib/string.c                            | 48 +++++++++++++++++++
>>   tools/lib/subcmd/help.c                       |  2 +-
>>   tools/lib/subcmd/parse-options.c              | 18 +++----
>>   tools/objtool/check.c                         |  2 +-
>>   tools/perf/arch/arm/util/pmu.c                |  4 +-
>>   tools/perf/arch/x86/annotate/instructions.c   | 14 +++---
>>   tools/perf/arch/x86/util/env.c                |  2 +-
>>   tools/perf/builtin-c2c.c                      |  4 +-
>>   tools/perf/builtin-config.c                   |  2 +-
>>   tools/perf/builtin-daemon.c                   |  2 +-
>>   tools/perf/builtin-ftrace.c                   |  2 +-
>>   tools/perf/builtin-help.c                     |  6 +--
>>   tools/perf/builtin-kmem.c                     |  2 +-
>>   tools/perf/builtin-kvm.c                      | 14 +++---
>>   tools/perf/builtin-kwork.c                    | 10 ++--
>>   tools/perf/builtin-lock.c                     |  6 +--
>>   tools/perf/builtin-mem.c                      |  4 +-
>>   tools/perf/builtin-sched.c                    |  6 +--
>>   tools/perf/builtin-script.c                   | 30 ++++--------
>>   tools/perf/builtin-stat.c                     |  4 +-
>>   tools/perf/builtin-timechart.c                |  2 +-
>>   tools/perf/builtin-trace.c                    |  6 +--
>>   tools/perf/perf.c                             | 12 ++---
>>   .../shell/test_uprobe_from_different_cu.sh    |  2 +-
>>   tools/perf/tests/symbols.c                    |  2 +-
>>   tools/perf/ui/browser.c                       |  2 +-
>>   tools/perf/ui/browsers/scripts.c              |  2 +-
>>   tools/perf/ui/stdio/hist.c                    |  2 +-
>>   tools/perf/util/amd-sample-raw.c              |  4 +-
>>   tools/perf/util/annotate.c                    |  2 +-
>>   tools/perf/util/callchain.c                   |  2 +-
>>   tools/perf/util/config.c                      | 12 ++---
>>   tools/perf/util/map.c                         |  8 ++--
>>   tools/perf/util/pmus.c                        |  2 +-
>>   tools/perf/util/probe-event.c                 |  2 +-
>>   tools/perf/util/sample-raw.c                  |  2 +-
>>   tools/perf/util/symbol-elf.c                  |  4 +-
>>   tools/perf/util/symbol.c                      |  3 +-
>>   39 files changed, 148 insertions(+), 117 deletions(-)
>>
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