[PATCH v2 00/10] tools/perf: Adopt kernel compiler-context-analysis.h annotations

[Ian Rogers]

The perf tool previously added Clang thread-safety annotations in
tools/perf/util/mutex.h (GUARDED_BY, LOCKABLE, EXCLUSIVE_LOCK_FUNCTION,
UNLOCK_FUNCTION, etc.). Since then, the Linux kernel has adopted a
unified set of static context analysis macros and attributes in
include/linux/compiler-context-analysis.h (context_lock_struct,
__guarded_by, __acquires, __releases, __must_hold, etc.).

This series makes tools/include/linux/compiler-context-analysis.h
functional by synchronizing it and the required compiler_types.h helpers
with the kernel headers, converts tools/perf from its custom mutex.h
macros to the kernel-style compiler-context-analysis.h annotations, and
expands context analysis coverage across comm, dso/dsos, thread/threads,
config, intel-tpebs, env, and maps. In the process, it fixes an unlocked
__dsos__add() call and TOCTOU race in __machine__addnew_vdso(), avoids
dropping dso__data_open_lock in dso__list_del() under REFCNT_CHECKING,
fixes an unlocked read of tpebs_reader_thread and double-close of
tpebs_cmd.out in intel-tpebs, avoids a potential read-to-write deadlock
in maps__load_first(), and adds a read-lock fast path to
dsos__findnew_id().

v2:
  - Use -c rather than -E when probing for
    -fexperimental-late-parse-attributes in Makefile.config to avoid
    -Werror,-Wunused-command-line-argument (patch 5).
  - Acquire machine->dsos.lock in write mode across duplicate checking,
    dso__set_long_name(), and __dsos__add() in __machine__addnew_vdso()
    (patch 7).
  - Release the REFCNT_CHECKING reference in dso__list_del() without
    dropping dso__data_open_lock, avoiding an unlocked window and AB-BA
    deadlock with dso->lock, and check dso__data(dso)->dso in dso__put()
    (patch 7).
  - Pass tpebs_cmd.out directly to __sample_reader() and set
    tpebs_cmd.out = -1 in evsel__tpebs_open() to avoid a double-close in
    tpebs_stop(), and clarify the config_set_mutex comment (patch 9).
  - Drop maps__lock before calling map__load() in maps__load_first() to
    avoid a read-to-write self-deadlock when loading kernel maps inserts
    additional trampoline maps (patch 10).

Ian Rogers (10):
  compiler-context-analysis: Avoid unused parameter warning in
    _context_unsafe_alias()
  tools headers compiler: Synchronize compiler_types.h with the kernel
    sources
  tools headers: Synchronize linux/compiler-context-analysis.h with the
    kernel sources
  perf mutex: Use kernel style compiler-context-analysis.h annotations
  perf build: Enable additional Clang thread-safety flags
  perf comm: Add __guarded_by annotations to struct comm_strs
  perf dso: Fix unlocked __dsos__add() in vdso and expand lock
    annotations
  perf thread: Expand context analysis annotations to threads and
    namespaces_lock
  perf config, intel-tpebs, env: Add __guarded_by and __must_hold
    annotations
  perf maps: Add context analysis annotations

 include/linux/compiler-context-analysis.h     |   2 +-
 .../include/linux/compiler-context-analysis.h | 518 ++++++++++++++++--
 tools/include/linux/compiler-gcc.h            |  55 +-
 tools/include/linux/compiler.h                |  50 +-
 tools/include/linux/compiler_types.h          | 206 ++++++-
 tools/perf/Makefile.config                    |   5 +-
 tools/perf/builtin-sched.c                    |  16 +-
 tools/perf/builtin-top.c                      |   4 +-
 tools/perf/check-headers.sh                   |   1 +
 tools/perf/tests/dso-data.c                   |   4 +
 tools/perf/util/annotate.c                    |   4 +-
 tools/perf/util/annotate.h                    |   8 +-
 tools/perf/util/bpf-event.h                   |   5 +-
 tools/perf/util/comm.c                        |  10 +-
 tools/perf/util/config.c                      |  43 +-
 tools/perf/util/dso.c                         |  93 ++--
 tools/perf/util/dso.h                         |  12 +-
 tools/perf/util/dsos.c                        |  35 +-
 tools/perf/util/dsos.h                        |  12 +-
 tools/perf/util/env.c                         |   1 +
 tools/perf/util/env.h                         |  19 +-
 tools/perf/util/intel-tpebs.c                 |  98 ++--
 tools/perf/util/libbfd.c                      |   4 +-
 tools/perf/util/maps.c                        | 133 +++--
 tools/perf/util/mutex.c                       |   4 +-
 tools/perf/util/mutex.h                       |  90 +--
 tools/perf/util/rwsem.c                       |   8 +-
 tools/perf/util/rwsem.h                       |  10 +-
 tools/perf/util/thread.c                      |  10 +-
 tools/perf/util/thread.h                      |  30 +-
 tools/perf/util/threads.c                     |   4 +
 tools/perf/util/threads.h                     |   6 +-
 tools/perf/util/vdso.c                        |  17 +-
 33 files changed, 1095 insertions(+), 422 deletions(-)

-- 
2.56.0.385.gd3acb90ef8-goog