Commit Graph

2 Commits

Author SHA1 Message Date
Ian Rogers
07eac17339 perf tests: Fix Python JIT dump profiling test failure
The `python profiling with jitdump` test failed due to:
1. Target PID extraction resolving to duplicate space-separated values,
   which broke the buildid-cache loops.
2. The default workload duration being too short to capture JIT stack
   trampoline samples, resulting in 0 matching JIT symbols.

Fix the PID parsing by sorting and retrieving a unique single-line value.
Implement a robust retry loop starting at 1M python loop iterations and
scaling up to 100M iterations until JIT symbols are successfully captured
and verified.

Fixes: c9cd0c7e52 ("perf test: Add python JIT dump test")
Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-06-30 17:09:13 -07:00
Namhyung Kim
c9cd0c7e52 perf test: Add python JIT dump test
Add a test case for the python interpreter like below so that we can
make sure it won't break again.  To validate the effect of build-ID
generation, it adds and removes the JIT'ed DSOs to/from the build-ID
cache for the test.

  $ perf test -vv jitdump
   84: python profiling with jitdump:
  --- start ---
  test child forked, pid 214316
  Run python with -Xperf_jit
  [ perf record: Woken up 5 times to write data ]
  [ perf record: Captured and wrote 1.180 MB /tmp/__perf_test.perf.data.XbqZNm (140 samples) ]
  Generate JIT-ed DSOs using perf inject
  Add JIT-ed DSOs to the build-ID cache
  Check the symbol containing the script name
  Found 108 matching lines
  Remove JIT-ed DSOs from the build-ID cache
  ---- end(0) ----
   84: python profiling with jitdump                                   : Ok

Cc: Pablo Galindo <pablogsal@gmail.com>
Link: https://docs.python.org/3/howto/perf_profiling.html#how-to-work-without-frame-pointers
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-12-02 16:06:57 -08:00