On Tue, Aug 19, 2025 at 05:10:46PM +0100, Daniel P. Berrangé wrote:
> To repeat the start of the commit message in patch 5....
>
> When reviewing tracetool patches it is often very unclear what the
> expected output will be for the generated backends. Compounding
> this is that a default build will only enable the 'log' trace
> backend, so developers won't see generated code for other backends
> without making a special effort. Some backends are also platform
> specific, so can't be enabled in QEMU builds, even though tracetool
> could generate the code.
>
> To address this, introduce a test suite for tracetool which is
> conceptually similar to the qapi-schema test. It is a simple
> python program that runs tracetool and compares the actual output
> to historical reference output kept in git.
>
> This was inspired by noticing the now pointless "__nocheck__"
> method wrapping in the inline probe functions.
>
> Changed in v4:
>
> - Drop patch adding '-' as an output filename for tracetool
> - Rewrite test to always use relative filenames for both
> inputs and outputs
> - Pass python code through 'black'
> - Minor docs punctuation tweak
> - Drop unused python method
>
> Changed in v3:
>
> - Also modify the QAPI schema test to use QEMU_TEST_REGENERATE=1
> env & document / hint this
> - Make tracetool accept '-' as shorthand for stdout to
> avoid relative paths in the reference output
>
> Changed in v2:
>
> - Add tracetool info to docs/devel/testing.rst
>
> Daniel P. Berrangé (7):
> checkpatch: cull trailing '*/' in SPDX check
> tracetool: eliminate trailing whitespace in C format
> tracetool: avoid space after "*" in arg types
> tracetool: include SPDX-License-Identifier in generated files
> tracetool: add test suite for tracetool with reference output
> tracetool: drop the probe "__nocheck__" wrapping
> qapi: switch to use QEMU_TEST_REGENERATE env var
>
> MAINTAINERS | 1 +
> docs/devel/testing/main.rst | 40 +++++++
> scripts/checkpatch.pl | 3 +
> scripts/tracetool/__init__.py | 9 +-
> scripts/tracetool/format/c.py | 3 +-
> scripts/tracetool/format/d.py | 3 +-
> scripts/tracetool/format/h.py | 17 +--
> scripts/tracetool/format/log_stap.py | 1 +
> scripts/tracetool/format/simpletrace_stap.py | 1 +
> scripts/tracetool/format/stap.py | 1 +
> scripts/tracetool/format/ust_events_c.py | 1 +
> scripts/tracetool/format/ust_events_h.py | 1 +
> tests/Makefile.include | 1 +
> tests/meson.build | 1 +
> tests/qapi-schema/test-qapi.py | 7 +-
> tests/tracetool/dtrace.c | 32 ++++++
> tests/tracetool/dtrace.d | 10 ++
> tests/tracetool/dtrace.h | 45 ++++++++
> tests/tracetool/dtrace.log-stap | 15 +++
> tests/tracetool/dtrace.simpletrace-stap | 16 +++
> tests/tracetool/dtrace.stap | 14 +++
> tests/tracetool/ftrace.c | 32 ++++++
> tests/tracetool/ftrace.h | 59 +++++++++++
> tests/tracetool/log.c | 32 ++++++
> tests/tracetool/log.h | 43 ++++++++
> tests/tracetool/meson.build | 25 +++++
> tests/tracetool/simple.c | 61 +++++++++++
> tests/tracetool/simple.h | 40 +++++++
> tests/tracetool/syslog.c | 32 ++++++
> tests/tracetool/syslog.h | 43 ++++++++
> tests/tracetool/trace-events | 5 +
> tests/tracetool/tracetool-test.py | 105 +++++++++++++++++++
> tests/tracetool/ust.c | 32 ++++++
> tests/tracetool/ust.h | 41 ++++++++
> tests/tracetool/ust.ust-events-c | 14 +++
> tests/tracetool/ust.ust-events-h | 56 ++++++++++
> 36 files changed, 821 insertions(+), 21 deletions(-)
> create mode 100644 tests/tracetool/dtrace.c
> create mode 100644 tests/tracetool/dtrace.d
> create mode 100644 tests/tracetool/dtrace.h
> create mode 100644 tests/tracetool/dtrace.log-stap
> create mode 100644 tests/tracetool/dtrace.simpletrace-stap
> create mode 100644 tests/tracetool/dtrace.stap
> create mode 100644 tests/tracetool/ftrace.c
> create mode 100644 tests/tracetool/ftrace.h
> create mode 100644 tests/tracetool/log.c
> create mode 100644 tests/tracetool/log.h
> create mode 100644 tests/tracetool/meson.build
> create mode 100644 tests/tracetool/simple.c
> create mode 100644 tests/tracetool/simple.h
> create mode 100644 tests/tracetool/syslog.c
> create mode 100644 tests/tracetool/syslog.h
> create mode 100644 tests/tracetool/trace-events
> create mode 100755 tests/tracetool/tracetool-test.py
> create mode 100644 tests/tracetool/ust.c
> create mode 100644 tests/tracetool/ust.h
> create mode 100644 tests/tracetool/ust.ust-events-c
> create mode 100644 tests/tracetool/ust.ust-events-h
>
> --
> 2.50.1
>
Thanks, applied to my tracing-next tree:
https://gitlab.com/stefanha/qemu/commits/tracing-next
Stefan