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

From: James Clark
Date: Mon Jul 15 2024 - 05:35:57 EST




On 15/07/2024 10:34 am, James Clark wrote:


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@xxxxxxx>

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@xxxxxxx/

- 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@xxxxxxx/

Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Cc: James Clark <james.clark@xxxxxxx>
Cc: John Garry <john.g.garry@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Chenyuan Mi <cymi20@xxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Ravi Bangoria <ravi.bangoria@xxxxxxx>
Cc: Ahelenia Ziemiańska <nabijaczleweli@xxxxxxxxxxxxxxxxxx>
Cc: Colin Ian King <colin.i.king@xxxxxxxxx>
Cc: Changbin Du <changbin.du@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Athira Rajeev <atrajeev@xxxxxxxxxxxxxxxxxx>
Cc: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Cc: Georg Müller <georgmueller@xxxxxxx>
Cc: Liam Howlett <liam.howlett@xxxxxxxxxx>
Cc: bpf@xxxxxxxxxxxxxxx
Cc: coresight@xxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-perf-users@xxxxxxxxxxxxxxx

Chaitanya S Prakash (10):
   tools lib: adopt str_has_suffix() from bpftool/gen.c

LGTM,

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

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()


There were some trivial merge conflicts though, so I'm not sure if it's worth sending a new version out or not.

   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(-)