linux/tools/lib/perf/include/internal, branch v6.8

libperf: Lazily allocate/size mmap event copy

2023-11-30T22:25:19Z

The event copy in the mmap is used to have storage to read an event. Not all users of mmaps read the events, such as perf record. The amount of buffer was also statically set to PERF_SAMPLE_MAX_SIZE rather than the amount necessary from the header's event size. Switch to a model where the event_copy is reallocated if too small to the event's size. This adds the potential for the event to move, so if a copy of the event pointer were stored it could be broken. All the current users do: while(event = perf_mmap__read_event()) { ... } and so they would be broken due to the event being overwritten if they had stored the pointer. Manual inspection and address sanitizer testing also shows the event pointer not being stored. Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Jajeev Cc: Changbin Du Cc: Colin Ian King Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez Cc: Guilherme Amadio Cc: Huacai Chen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: K Prateek Nayak Cc: Kajol Jain Cc: Kan Liang Cc: Leo Yan Cc: Li Dong Cc: Liam Howlett Cc: Mark Rutland Cc: Masami Hiramatsu (Google) Cc: Miguel Ojeda Cc: Ming Wang Cc: Nick Terrell Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sandipan Das Cc: Sean Christopherson Cc: Steinar H. Gunderson Cc: Vincent Whitchurch Cc: Wenyu Liu Cc: Yang Jihong Link: https://lore.kernel.org/r/20231127220902.1315692-3-irogers@google.com [ Replace two lines with equivalent zfree(&map->event_copy) ] Signed-off-by: Arnaldo Carvalho de Melo

libperf rc_check: Add RC_CHK_EQUAL

2023-10-25T20:37:22Z

Comparing pointers with reference count checking is tricky to avoid a SEGV. Add a convenience macro to simplify and use. Signed-off-by: Ian Rogers Cc: K Prateek Nayak Cc: Ravi Bangoria Cc: Sandipan Das Cc: Anshuman Khandual Cc: German Gomez Cc: James Clark Cc: Nick Terrell Cc: Sean Christopherson Cc: Changbin Du Cc: liuwenyu Cc: Yang Jihong Cc: Masami Hiramatsu Cc: Miguel Ojeda Cc: Song Liu Cc: Leo Yan Cc: Kajol Jain Cc: Andi Kleen Cc: Kan Liang Cc: Athira Rajeev Cc: Yanteng Si Cc: Liam Howlett Cc: Paolo Bonzini Link: https://lore.kernel.org/r/20231024222353.3024098-5-irogers@google.com Signed-off-by: Namhyung Kim

libperf rc_check: Make implicit enabling work for GCC

2023-10-25T20:36:50Z

Make the implicit REFCOUNT_CHECKING robust to when building with GCC. Fixes: 9be6ab181b7b ("libperf rc_check: Enable implicitly with sanitizers") Signed-off-by: Ian Rogers Cc: K Prateek Nayak Cc: Ravi Bangoria Cc: Sandipan Das Cc: Anshuman Khandual Cc: German Gomez Cc: James Clark Cc: Nick Terrell Cc: Sean Christopherson Cc: Changbin Du Cc: liuwenyu Cc: Yang Jihong Cc: Masami Hiramatsu Cc: Miguel Ojeda Cc: Song Liu Cc: Leo Yan Cc: Kajol Jain Cc: Andi Kleen Cc: Kan Liang Cc: Athira Rajeev Cc: Yanteng Si Cc: Liam Howlett Cc: Paolo Bonzini Link: https://lore.kernel.org/r/20231024222353.3024098-4-irogers@google.com Signed-off-by: Namhyung Kim

perf evlist: Add perf_evlist__go_system_wide() helper

2023-09-12T20:31:22Z

For dummy events that keep tracking, we may need to modify its cpu_maps. For example, change the cpu_maps to record sideband events for all CPUS. Add perf_evlist__go_system_wide() helper to support this scenario. Signed-off-by: Yang Jihong Acked-by: Adrian Hunter Tested-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Andi Kleen Cc: Anshuman Khandual Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Link: https://lore.kernel.org/r/20230904023340.12707-2-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Propagate user CPU maps intersecting core PMU maps

2023-05-27T12:38:39Z

The CPU map for a non-core PMU gives a default CPU value for perf_event_open. For core PMUs the CPU map lists all CPUs the evsel may be opened on. If there are >1 core PMU, the CPU maps will list the CPUs for that core PMU, but the user_requested_cpus may contain CPUs that are invalid for the PMU and cause perf_event_open to fail. To avoid this, when propagating the CPU map for core PMUs intersect it with the CPU map of the PMU (the evsel's "own_cpus"). Add comments to __perf_evlist__propagate_maps to explain its somewhat complex behavior. Fix the related comments for system_wide in struct perf_evsel. Reviewed-by: Kan Liang Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ali Saidi Cc: Athira Rajeev Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Huacai Chen Cc: Ingo Molnar Cc: James Clark Cc: Jing Zhang Cc: Jiri Olsa Cc: John Garry Cc: Kajol Jain Cc: Kang Minchul Cc: Leo Yan Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Mike Leach Cc: Ming Wang Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Rob Herring Cc: Sandipan Das Cc: Sean Christopherson Cc: Suzuki Poulouse Cc: Thomas Richter Cc: Will Deacon Cc: Xing Zhengjun Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20230527072210.2900565-9-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Add is_pmu_core inorder to interpret own_cpus

2023-05-27T12:38:10Z

The behaviour of handling cpu maps varies for core and other PMUs. For core PMUs the cpu map lists all valid CPUs, whereas for other PMUs the map is the default CPU. Add a flag in the evsel to indicate if a PMU is core to help with later interpreting of the cpu maps and populate it when the evsel is created during parsing. When propagating cpu maps, core PMUs should intersect the cpu map of the PMU with the user requested one. Reviewed-by: Kan Liang Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ali Saidi Cc: Athira Rajeev Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Huacai Chen Cc: Ingo Molnar Cc: James Clark Cc: Jing Zhang Cc: Jiri Olsa Cc: John Garry Cc: Kajol Jain Cc: Kang Minchul Cc: Leo Yan Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Mike Leach Cc: Ming Wang Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Rob Herring Cc: Sandipan Das Cc: Sean Christopherson Cc: Suzuki Poulouse Cc: Thomas Richter Cc: Will Deacon Cc: Xing Zhengjun Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20230527072210.2900565-7-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

libperf rc_check: Enable implicitly with sanitizers

2023-04-20T18:12:02Z

If using leak sanitizer then implicitly enable reference count checking. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20230420171812.561603-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf cpumap: Add reference count checking

2023-04-17T19:50:02Z

Enabled when REFCNT_CHECKING is defined. The change adds a memory allocated pointer that is interposed between the reference counted cpu map at a get and freed by a put. The pointer replaces the original perf_cpu_map struct, so use of the perf_cpu_map via APIs remains unchanged. Any use of the cpu map without the API requires two versions, handled via the RC_CHK_ACCESS macro. This change is intended to catch: - use after put: using a cpumap after you have put it will cause a segv. - unbalanced puts: two puts for a get will result in a double free that can be captured and reported by tools like address sanitizer, including with the associated stack traces of allocation and frees. - missing puts: if a put is missing then the get turns into a memory leak that can be reported by leak sanitizer, including the stack trace at the point the get occurs. Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Bayduraev Cc: Andi Kleen Cc: Andrew Morton Cc: Andy Shevchenko Cc: Darren Hart Cc: Davidlohr Bueso Cc: Dmitriy Vyukov Cc: Eric Dumazet Cc: German Gomez Cc: Hao Luo Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Kajol Jain Cc: Kan Liang Cc: Leo Yan Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Miaoqian Lin Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Riccardo Mancini Cc: Shunsuke Nakamura Cc: Song Liu Cc: Stephen Brennan Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Cc: Thomas Richter , Cc: Yury Norov Link: https://lore.kernel.org/lkml/20230407230405.2931830-3-irogers@google.com [ Extracted from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo

libperf: Add reference count checking macros

2023-04-17T18:53:01Z

The macros serve as a way to debug use of a reference counted struct. The macros add a memory allocated pointer that is interposed between the reference counted original struct at a get and freed by a put. The pointer replaces the original struct, so use of the struct name via APIs remains unchanged. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Bayduraev Cc: Andi Kleen Cc: Andrew Morton Cc: Andy Shevchenko Cc: Darren Hart Cc: Davidlohr Bueso Cc: Dmitriy Vyukov Cc: Eric Dumazet Cc: German Gomez Cc: Hao Luo Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Kajol Jain Cc: Kan Liang Cc: Leo Yan Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Miaoqian Lin Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Riccardo Mancini Cc: Shunsuke Nakamura Cc: Song Liu Cc: Stephane Eranian Cc: Stephen Brennan Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Cc: Thomas Richter Cc: Yury Norov Link: http://lore.kernel.org/lkml/20230407230405.2931830-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

libperf: Add perf_cpu_map__refcnt() interanl accessor to use in the maps test

2023-04-17T18:52:36Z

To remove one more direct access to 'struct perf_cpu_map' so that we can intercept accesses to its instantiations and refcount check it to catch use after free, etc. Cc: Adrian Hunter Cc: Alexey Bayduraev Cc: Dmitriy Vyukov Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: Riccardo Mancini Cc: Stephane Eranian Cc: Stephen Brennan Link: https://lore.kernel.org/lkml/ZD1qdYjG+DL6KOfP@kernel.org Signed-off-by: Arnaldo Carvalho de Melo