kernel/git/stable/linux.git/tools/perf/util/unwind-libunwind-local.c, branch master

perf unwind-libunwind: Remove libunwind-local

2026-05-15T19:19:50+00:00

Local unwinding only works on the machine libunwind is built for, rather than cross platform, the APIs for remote and local unwinding are similar but types like unw_word_t depend on the included header. Place the architecture specific code into the appropriate libunwind-.c file. Put generic code in unwind-libunwind.c and use libunwind-arch to choose the correct implementation based on the thread's e_machine. Structuring the code this way avoids including the unwind-libunwind-local.c for each architecture of remote unwinding. Data is moved into the struct unwind_info to simplify the architecture and generic code, trying to keep as much code as possible generic. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andrew Jones Cc: Athira Rajeev Cc: Dapeng Mi Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Florian Fainelli Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Li Guan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Shimin Guo Cc: Thomas Richter Cc: Tomas Glozar Cc: Will Deacon Signed-off-by: Arnaldo Carvalho de Melo

perf unwind-libunwind: Move flush/finish access out of local

2026-05-15T19:19:50+00:00

Flush and finish access are relatively simple calls into libunwind, move them out struct unwind_libunwind_ops. So that the correct version can be called, add an e_machine variable to maps. This size regression will go away when the unwind_libunwind_ops no longer need stashing in the maps. To set the e_machine up pass it into unwind__prepare_access, which no longer needs to determine the unwind operations based on a map dso because of this. This also means the maps copying code can call unwind__prepare_access once for the e_machine rather than once per map. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andrew Jones Cc: Athira Rajeev Cc: Dapeng Mi Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Florian Fainelli Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Li Guan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Shimin Guo Cc: Thomas Richter Cc: Tomas Glozar Cc: Will Deacon Signed-off-by: Arnaldo Carvalho de Melo

perf unwind-libunwind: Make libunwind register reading cross platform

2026-05-15T19:18:36+00:00

Move the libunwind register to perf register mapping functions in arch/../util/unwind-libunwind.c into a new libunwind-arch directory. Rename the functions to __get_perf_regnum_for_unw_regnum_. Add untested ppc32 and s390 functions. Add a get_perf_regnum_for_unw_regnum function that takes an ELF machine as well as a register number and chooses the appropriate architecture implementation. Split the x86 and powerpc 32 and 64-bit implementations apart so that a single libunwind-.h header is included. Move the e_machine into the unwind_info struct to make it easier to pass. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andrew Jones Cc: Athira Rajeev Cc: Dapeng Mi Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Florian Fainelli Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Li Guan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Shimin Guo Cc: Thomas Richter Cc: Tomas Glozar Cc: Will Deacon [ Map UNW_PPC32_NIP to PERF_REG_POWERPC_NIP like done for 64-bit, pointed out by a local sashiko ] Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Refactor get_entries to allow dynamic libdw/libunwind selection

2026-05-15T11:25:02+00:00

Currently, both libdw and libunwind define 'unwind__get_entries'. This causes a duplicate symbol build failure when both are compiled into perf. This commit refactors the DWARF unwind post-processing to be configurable at runtime via the .perfconfig file option 'unwind.style', or using the argument '--unwind-style' in the commands 'perf report', 'perf script' and 'perf inject', in a similar manner to the addr2line or the disassembler style. The file 'tools/perf/util/unwind.c' adds the top-level dispatch function 'unwind__get_entries'. The backend implementations are renamed to 'libdw__get_entries' and 'libunwind__get_entries'. Both are attempted as fallbacks if not configured, or if the primary backend fails. Fixes: 2e9191573a69ff96 ("perf build: Remove NO_LIBDW_DWARF_UNWIND option") Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andrew Jones Cc: Athira Rajeev Cc: Dapeng Mi Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Florian Fainelli Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: libunwind-devel@nongnu.org Cc: Li Guan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Shimin Guo Cc: Thomas Richter Cc: Tomas Glozar Cc: Will Deacon [ Don't mix declarations and code, move 'entries' variable to the start of scope ] [ Use pr_warning_once() instead of pr_err() in stubs for get_entries(), suggested by a local sashiko instance ] Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use calloc() where applicable

2026-04-09T02:21:05+00:00

Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc() does. In some places where linux/zalloc.h isn't needed, remove it, add when needed and was getting it indirectly. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

perf libunwind: Fix calls to thread__e_machine()

2026-02-12T20:45:22+00:00

Add the missing 'e_flags' option to fix the build. Fixes: 4e66527f8859a661 ("perf thread: Add optional e_flags output argument to thread__e_machine") Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf map_symbol: Switch from holding maps to holding thread

2026-01-23T19:58:39+00:00

maps may belong to >1 thread. In contexts like symbolization information from the thread may be useful, such as the ELF machine. As the maps can be gained from the thread switch from holding maps in struct map_symbol to holding the thread. Holding the maps in addr_location is also redundant, switch this to using thread__maps. Reviewed-by: James Clark Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Athira Rajeev Cc: Bill Wendling Cc: Dr. David Alan Gilbert Cc: Guo Ren Cc: Howard Chu Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Julia Lawall Cc: Justin Stitt Cc: Krzysztof Łopatowski Cc: Leo Yan Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Sergei Trofimovich Cc: Shimin Guo Cc: Suchit Karunakaran Cc: Thomas Falcon Cc: Tianyou Li Cc: Will Deacon Cc: Zecheng Li Signed-off-by: Arnaldo Carvalho de Melo

perf perf_regs: Switch from arch string to int e_machine

2026-01-20T18:43:04+00:00

The arch string requires multiple strcmp to identify things like the IP and SP. Switch to passing in an e_machine that in the bulk of cases is computed using a current thread load. The e_machine also allows identification of 32-bit vs 64-bit processes. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Chun-Tse Shao Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Guo Ren Cc: Haibo Xu Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Krzysztof Łopatowski Cc: Leo Yan Cc: Mark Wielaard Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Sergei Trofimovich Cc: Shimin Guo Cc: Stephen Brennan Cc: Thomas Falcon Cc: Will Deacon [ Include dwarf-regs.h to get conditional defines for EM_CSKY and EM_LOONGARCH, not available in old distros ] Signed-off-by: Arnaldo Carvalho de Melo

perf libunwind arm64: Fix missing close parens in an if statement

2025-04-11T00:51:31+00:00

While testing building with libunwind (using LIBUNWIND=1) in various arches I noticed a problem on arm64, on an rpi5 system, a missing close parens in a change related to dso__data_get_fd() usage, fix it. Fixes: 5ac22c35aa8519f1 ("perf dso: Use lock annotations to fix asan deadlock") Signed-off-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/Z_Z3o8KvB2i5c6ab@x1 Signed-off-by: Namhyung Kim

perf dso: Use lock annotations to fix asan deadlock

2025-03-18T05:07:18+00:00

dso__list_del with address sanitizer and/or reference count checking will call dso__put that can call dso__data_close reentrantly trying to lock the dso__data_open_lock and deadlocking. Switch from pthread mutexes to perf's mutex so that lock checking is performed in debug builds. Add lock annotations that diagnosed the problem. Release the dso__data_open_lock around the dso__put to avoid the deadlock. Change the declaration of dso__data_get_fd to return a boolean, indicating the fd is valid and the lock is held, to make it compatible with the thread safety annotations as a try lock. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250318043151.137973-3-irogers@google.com Signed-off-by: Namhyung Kim