]> www.infradead.org Git - users/jedix/linux-maple.git/commit
perf arm-spe: Add branch stack
authorLeo Yan <leo.yan@arm.com>
Tue, 4 Mar 2025 11:12:39 +0000 (11:12 +0000)
committerNamhyung Kim <namhyung@kernel.org>
Wed, 5 Mar 2025 17:13:20 +0000 (09:13 -0800)
commit73cb57f56f749ac640b889f076d5db96264020f8
treee70190fe40ff0028ad8872dc6322624c532900a5
parent4a53a67e0eeed768515840f8e3c36dc399663e2a
perf arm-spe: Add branch stack

Although Arm SPE cannot generate continuous branch records, this commit
creates a branch stack with only one branch entry.  A single branch info
can be used for performance optimization.

A branch stack structure is dynamically allocated in the decode queue.
The branch stack and stack flags are synthesized based on branch types
and associated events.

After:

  # perf script --itrace=bl1 -F flags,addr,brstack

  jcc                   ffffc0fad9c6b214 0xffffc0fad9c6b234/0xffffc0fad9c6b214/P/-/-/7/COND/-
  jcc/miss,not_taken/   ffffc0fadaaebb30 0xffffc0fadaaebb2c/0xffffc0fadaaebb30/MN/-/-/7/COND/-
  jmp                   ffffc0fadaaea358 0xffffc0fadaaea5ec/0xffffc0fadaaea358/P/-/-/5//-
  jcc/not_taken/        ffffc0fadaae6494 0xffffc0fadaae6490/0xffffc0fadaae6494/PN/-/-/11/COND/-
  jcc/not_taken/            ffff7f83ab54 0xffff7f83ab50/0xffff7f83ab54/PN/-/-/13/COND/-
  jcc/not_taken/            ffff7f83ab08 0xffff7f83ab04/0xffff7f83ab08/PN/-/-/8/COND/-
  jcc                       ffff7f83aa80 0xffff7f83aa58/0xffff7f83aa80/P/-/-/10/COND/-
  jcc                       ffff7f9a45d0 0xffff7f9a43f0/0xffff7f9a45d0/P/-/-/29/COND/-
  jcc/not_taken/        ffffc0fad9ba6db4 0xffffc0fad9ba6db0/0xffffc0fad9ba6db4/PN/-/-/44/COND/-
  jcc                   ffffc0fadaac2964 0xffffc0fadaac2970/0xffffc0fadaac2964/P/-/-/6/COND/-
  jcc                   ffffc0fad99ddc10 0xffffc0fad99ddc04/0xffffc0fad99ddc10/P/-/-/72/COND/-
  jcc/not_taken/        ffffc0fad9b3f21c 0xffffc0fad9b3f218/0xffffc0fad9b3f21c/PN/-/-/64/COND/-
  jcc                   ffffc0fad9c3b604 0xffffc0fad9c3b5f8/0xffffc0fad9c3b604/P/-/-/13/COND/-
  jcc                   ffffc0fadaad6048 0xffffc0fadaad5f8c/0xffffc0fadaad6048/P/-/-/5/COND/-
  return/miss/              ffff7f84e614 0xffffc0fad98a2274/0xffff7f84e614/M/-/-/13/RET/-
  jcc/not_taken/        ffffc0fadaac4eb4 0xffffc0fadaac4eb0/0xffffc0fadaac4eb4/PN/-/-/5/COND/-
  jmp                       ffff7f8e3130 0xffff7f87555c/0xffff7f8e3130/P/-/-/5//-
  jcc/not_taken/        ffffc0fad9b3d9b0 0xffffc0fad9b3d9ac/0xffffc0fad9b3d9b0/PN/-/-/14/COND/-
  return                ffffc0fad9b91950 0xffffc0fad98c3e28/0xffffc0fad9b91950/P/-/-/12/RET/-

Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Link: https://lore.kernel.org/r/20250304111240.3378214-12-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
tools/perf/util/arm-spe.c