Messages in this thread | | | From | Ian Rogers <> | Date | Tue, 24 May 2022 22:01:01 -0700 | Subject | Re: [PATCH V4 00/15] perf intel-pt: Better support for perf record --cpu |
| |
On Tue, May 24, 2022 at 12:55 AM Adrian Hunter <adrian.hunter@intel.com> wrote: > > Hi > > Here are V4 patches to support capturing Intel PT sideband events such as > mmap, task, context switch, text poke etc, on every CPU even when tracing > selected user_requested_cpus. That is, when using the perf record -C or > --cpu option. > > This is needed for: > 1. text poke: a text poke on any CPU affects all CPUs > 2. tracing user space: a user space process can migrate between CPUs so > mmap events that happen on a different CPU can be needed to decode a > user_requested_cpus CPU. > > For example: > > Trace on CPU 1: > > perf record --kcore -C 1 -e intel_pt// & > > Start a task on CPU 0: > > taskset 0x1 testprog & > > Migrate it to CPU 1: > > taskset -p 0x2 <testprog pid> > > Stop tracing: > > kill %1 > > Prior to these changes there will be errors decoding testprog > in userspace because the comm and mmap events for testprog will not > have been captured. > > There is quite a bit of preparation: > > The first patch is a small Intel PT test for system-wide side band. The > test fails before the patches are applied, passed afterwards. > > perf intel-pt: Add a test for system-wide side band [new in V1] > > The next 5 patches (now already applied) stop auxtrace mixing up mmap idx > between evlist and evsel. That is going to matter when > evlist->all_cpus != evlist->user_requested_cpus != evsel->cpus: > > libperf evsel: Factor out perf_evsel__ioctl() [now applied] > libperf evsel: Add perf_evsel__enable_thread() > perf evlist: Use libperf functions in evlist__enable_event_idx() > perf auxtrace: Move evlist__enable_event_idx() to auxtrace.c > perf auxtrace: Do not mix up mmap idx > > The next 6 patches (first 4 now already applied) stop attempts to auxtrace > mmap when it is not an auxtrace event e.g. when mmapping the CPUs on which > only sideband is captured: > > libperf evlist: Remove ->idx() per_cpu parameter > libperf evlist: Move ->idx() into mmap_per_evsel() > libperf evlist: Add evsel as a parameter to ->idx() > perf auxtrace: Record whether an auxtrace mmap is needed > perf auxctrace: Add mmap_needed to auxtrace_mmap_params > perf auxtrace: Remove auxtrace_mmap_params__set_idx() per_cpu parameter > > The next 5 patches switch to setting up dummy event maps before adding the > evsel so that the evsel is subject to map propagation, primarily to cause > addition of the evsel's CPUs to all_cpus. > > perf evlist: Factor out evlist__dummy_event() > perf evlist: Add evlist__add_system_wide_dummy() > perf record: Use evlist__add_system_wide_dummy() in record__config_text_poke() > perf intel-pt: Use evlist__add_system_wide_dummy() for switch tracking > perf intel-pt: Track sideband system-wide when needed > > The remaining patches make more significant changes. > > First change from using user_requested_cpus to using all_cpus where necessary: > > perf tools: Allow all_cpus to be a superset of user_requested_cpus > > Secondly, mmap all per-thread and all per-cpu events: > > libperf evlist: Allow mixing per-thread and per-cpu mmaps > libperf evlist: Check nr_mmaps is correct [new in V1] > > Stop using system_wide flag for uncore because it will not work anymore: > > perf stat: Add requires_cpu flag for uncore > libperf evsel: Add comments for booleans [new in V1] > > Finally change map propagation so that system-wide events retain their cpus and > (dummy) threads: > > perf tools: Allow system-wide events to keep their own CPUs > perf tools: Allow system-wide events to keep their own threads > > > Changes in V4: > > Added Acked-by: Namhyung Kim <namhyung@kernel.org> > Added a couple Acked-by: Ian Rogers <irogers@google.com>
Would love to see this merged Arnaldo, I can do an:
Acked-by: Ian Rogers <irogers@google.com>
in case it helps you with b4 a little :-)
Thanks, Ian
> perf intel-pt: Add a test for system-wide side band > Put in commit message that test succeeds only after other > patches applied > > libperf evsel: Add perf_evsel__enable_thread() > perf evlist: Use libperf functions in evlist__enable_event_idx() > perf auxtrace: Move evlist__enable_event_idx() to auxtrace.c > perf auxtrace: Do not mix up mmap idx > libperf evlist: Remove ->idx() per_cpu parameter > libperf evlist: Move ->idx() into mmap_per_evsel() > libperf evlist: Add evsel as a parameter to ->idx() > perf auxtrace: Record whether an auxtrace mmap is needed > Omitted because already applied > > libperf evsel: Add comments for booleans > Amended comment about own_cpus > > > Changes in V3: > > perf auxtrace: Add mmap_needed to auxtrace_mmap_params > Amended mmap_needed comment > > perf evlist: Add evlist__add_dummy_on_all_cpus() > Amended comment about all CPUs. > > > Changes in V2: > > Added some Acked-by: Ian Rogers <irogers@google.com> > > libperf evsel: Add perf_evsel__enable_thread() > Use perf_cpu_map__for_each_cpu() > > perf auxtrace: Add mmap_needed to auxtrace_mmap_params > Add documentation comment for mmap_needed > > perf auxtrace: Remove auxtrace_mmap_params__set_idx() per_cpu parameter > Fix missing auxtrace_mmap_params__set_idx change > > libperf evlist: Check nr_mmaps is correct > Remove unused code > > libperf evsel: Add comments for booleans > Amend comments > > perf evlist: Add evlist__add_dummy_on_all_cpus() > Rename evlist__add_system_wide -> evlist__add_on_all_cpus > Changed patch subject accordingly > > perf record: Use evlist__add_dummy_on_all_cpus() in record__config_text_poke() > Rename evlist__add_system_wide -> evlist__add_on_all_cpus > Changed patch subject accordingly > > perf intel-pt: Use evlist__add_dummy_on_all_cpus() for switch tracking > Rename evlist__add_system_wide -> evlist__add_on_all_cpus > Changed patch subject accordingly > > > Changes in V1: > > perf intel-pt: Add a test for system-wide side band > New patch > > libperf evsel: Factor out perf_evsel__ioctl() > Dropped because it has been applied. > > libperf evsel: Add perf_evsel__enable_thread() > Rename variable i -> idx > > perf auxtrace: Do not mix up mmap idx > Rename variable cpu to cpu_map_idx > > perf tools: Allow all_cpus to be a superset of user_requested_cpus > Add Acked-by: Ian Rogers <irogers@google.com> > > libperf evlist: Allow mixing per-thread and per-cpu mmaps > Fix perf_evlist__nr_mmaps() calculation > > libperf evlist: Check nr_mmaps is correct > New patch > > libperf evsel: Add comments for booleans > New patch > > perf tools: Allow system-wide events to keep their own CPUs > perf tools: Allow system-wide events to keep their own threads > > > Adrian Hunter (15): > perf intel-pt: Add a test for system-wide side band > perf auxtrace: Add mmap_needed to auxtrace_mmap_params > perf auxtrace: Remove auxtrace_mmap_params__set_idx() per_cpu parameter > perf evlist: Factor out evlist__dummy_event() > perf evlist: Add evlist__add_dummy_on_all_cpus() > perf record: Use evlist__add_dummy_on_all_cpus() in record__config_text_poke() > perf intel-pt: Use evlist__add_dummy_on_all_cpus() for switch tracking > perf intel-pt: Track sideband system-wide when needed > perf tools: Allow all_cpus to be a superset of user_requested_cpus > libperf evlist: Allow mixing per-thread and per-cpu mmaps > libperf evlist: Check nr_mmaps is correct > perf stat: Add requires_cpu flag for uncore > libperf evsel: Add comments for booleans > perf tools: Allow system-wide events to keep their own CPUs > perf tools: Allow system-wide events to keep their own threads > > tools/lib/perf/evlist.c | 71 ++++++++++++++------------------- > tools/lib/perf/include/internal/evsel.h | 11 +++++ > tools/perf/arch/x86/util/intel-pt.c | 31 ++++++-------- > tools/perf/builtin-record.c | 39 +++++++----------- > tools/perf/builtin-stat.c | 5 +-- > tools/perf/tests/shell/test_intel_pt.sh | 71 +++++++++++++++++++++++++++++++++ > tools/perf/util/auxtrace.c | 15 +++++-- > tools/perf/util/auxtrace.h | 13 ++++-- > tools/perf/util/evlist.c | 61 +++++++++++++++++++++++++--- > tools/perf/util/evlist.h | 5 +++ > tools/perf/util/evsel.c | 1 + > tools/perf/util/mmap.c | 4 +- > tools/perf/util/parse-events.c | 2 +- > 13 files changed, 226 insertions(+), 103 deletions(-) > create mode 100755 tools/perf/tests/shell/test_intel_pt.sh > > > Regards > Adrian
| |