kernel/linux.git/tools/perf/util/dso.c, branch v6.1.168

perf dso: Hold lock when accessing nsinfo

2022-10-04T11:55:20+00:00

There may be threads racing to update dso->nsinfo: https://lore.kernel.org/linux-perf-users/CAP-5=fWZH20L4kv-BwVtGLwR=Em3AOOT+Q4QGivvQuYn5AsPRg@mail.gmail.com/ Holding the dso->lock avoids use-after-free, memory leaks and other such bugs. Apply the fix in: https://lore.kernel.org/linux-perf-users/20211118193714.2293728-1-irogers@google.com/ of there being a missing nsinfo__put now that the accesses are data race free. Fixes test "Lookup mmap thread" when compiled with address sanitizer. Signed-off-by: Ian Rogers Reviewed-by: Adrian Hunter Cc: Alexander Shishkin Cc: Alexandre Truong Cc: Alexey Bayduraev Cc: Andi Kleen Cc: Andres Freund Cc: Andrii Nakryiko Cc: André Almeida Cc: Athira Jajeev Cc: Christophe JAILLET Cc: Colin Ian King Cc: Dario Petrillo Cc: Darren Hart Cc: Dave Marchevsky Cc: Davidlohr Bueso Cc: Fangrui Song Cc: Hewenliang Cc: Ingo Molnar Cc: James Clark Cc: Jason Wang Cc: Jiri Olsa Cc: Kajol Jain Cc: Kim Phillips Cc: Leo Yan Cc: Mark Rutland Cc: Martin Liška Cc: Masami Hiramatsu Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Pavithra Gurushankar Cc: Peter Zijlstra Cc: Quentin Monnet Cc: Ravi Bangoria Cc: Remi Bernon Cc: Riccardo Mancini Cc: Song Liu Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Thomas Richter Cc: Tom Rix Cc: Weiguo Li Cc: Wenyu Liu Cc: William Cohen Cc: Zechuan Chen Cc: bpf@vger.kernel.org Cc: llvm@lists.linux.dev Cc: yaowenbin Link: https://lore.kernel.org/r/20220826164242.43412-15-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Update use of pthread mutex

2022-10-04T11:55:20+00:00

Switch to the use of mutex wrappers that provide better error checking. Signed-off-by: Ian Rogers Reviewed-by: Adrian Hunter Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Alexandre Truong Cc: Alexey Bayduraev Cc: Andi Kleen Cc: Andres Freund Cc: Andrii Nakryiko Cc: André Almeida Cc: Athira Jajeev Cc: Christophe JAILLET Cc: Colin Ian King Cc: Dario Petrillo Cc: Darren Hart Cc: Dave Marchevsky Cc: Davidlohr Bueso Cc: Fangrui Song Cc: Hewenliang Cc: Ingo Molnar Cc: James Clark Cc: Jason Wang Cc: Jiri Olsa Cc: Kajol Jain Cc: Kim Phillips Cc: Leo Yan Cc: Mark Rutland Cc: Martin Liška Cc: Masami Hiramatsu Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Pavithra Gurushankar Cc: Peter Zijlstra Cc: Quentin Monnet Cc: Ravi Bangoria Cc: Remi Bernon Cc: Riccardo Mancini Cc: Song Liu Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Thomas Richter Cc: Tom Rix Cc: Weiguo Li Cc: Wenyu Liu Cc: William Cohen Cc: Zechuan Chen Cc: bpf@vger.kernel.org Cc: llvm@lists.linux.dev Cc: yaowenbin Link: https://lore.kernel.org/r/20220826164242.43412-12-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Try chroot'ed filename when opening dso/symbol

2022-02-10T18:32:25+00:00

Currently it doesn't handle tasks in chroot properly. As filenames in MMAP records base on their root directory, it's different than what perf tool can see from outside. Add filename_with_chroot() helper to deal with those cases. The function returns a new filename only if it's in a different root directory. Since it needs to access /proc for the process, it only works until the task exits. With this change, I can see symbols in my program like below. # perf record -o- chroot myroot myprog 3 | perf report -i- ... # # Overhead Command Shared Object Symbol # ........ ....... ................. ............................. # 99.83% myprog myprog [.] loop 0.04% chroot [kernel.kallsyms] [k] fxregs_fixup 0.04% chroot [kernel.kallsyms] [k] rsm_load_seg_32 ... Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Ian Rogers Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20220202070828.143303-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf bpf: Pull in bpf_program__get_prog_info_linear()

2021-11-01T21:16:40+00:00

To prepare for impending deprecation of libbpf's bpf_program__get_prog_info_linear(), pull in the function and associated helpers into the perf codebase and migrate existing uses to the perf copy. Since libbpf's deprecated definitions will still be visible to perf, it is necessary to rename perf's definitions. Signed-off-by: Dave Marchevsky Acked-by: Andrii Nakryiko Acked-by: Song Liu Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Ingo Molnar Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20211011082031.4148337-4-davemarchevsky@fb.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Allow build-id with trailing zeros

2021-09-11T19:04:47+00:00

Currently perf saves a build-id with size but old versions assumes the size of 20. In case the build-id is less than 20 (like for MD5), it'd fill the rest with 0s. I saw a problem when old version of perf record saved a binary in the build-id cache and new version of perf reads the data. The symbols should be read from the build-id cache (as the path no longer has the same binary) but it failed due to mismatch in the build-id. symsrc__init: build id mismatch for /home/namhyung/.debug/.build-id/53/e4c2f42a4c61a2d632d92a72afa08f00000000/elf. The build-id event in the data has 20 byte build-ids, but it saw a different size (16) when it reads the build-id of the elf file in the build-id cache. $ readelf -n ~/.debug/.build-id/53/e4c2f42a4c61a2d632d92a72afa08f00000000/elf Displaying notes found in: .note.gnu.build-id Owner Data size Description GNU 0x00000010 NT_GNU_BUILD_ID (unique build ID bitstring) Build ID: 53e4c2f42a4c61a2d632d92a72afa08f Let's fix this by allowing trailing zeros if the size is different. Fixes: 39be8d0115b321ed ("perf tools: Pass build_id object to dso__build_id_equal()") Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Ian Rogers Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210910224630.1084877-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Fix memory leak in dso__new_map()

2021-07-15T20:27:52+00:00

ASan reports a memory leak when running: # perf test "65: maps__merge_in". The causes of the leaks are two, this patch addresses only the first one, which is related to dso__new_map(). The bug is that dso__new_map() creates a new dso but never decreases the refcount it gets from creating it. This patch adds the missing dso__put(). Signed-off-by: Riccardo Mancini Fixes: d3a7c489c7fd2463 ("perf tools: Reference count struct dso") Cc: Ian Rogers Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/60bfe0cd06e89e2ca33646eb8468d7f5de2ee597.1626343282.git.rickyman7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add filename__decompress function

2020-11-27T11:36:53+00:00

Factor filename__decompress from decompress_kmodule function. It can decompress files with compressions supported in perf - xz and gz, the support needs to be compiled in. It will to be used in following changes to get build id out of compressed elf objects. Signed-off-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Budankov Cc: Andi Kleen Cc: Ian Rogers Cc: Mark Rutland Cc: Michael Petlan Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20201126170026.2619053-9-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf env: Conditionally compile BPF support code on having HAVE_LIBBPF_SUPPORT

2020-11-04T12:42:41+00:00

If libbpf isn't selected, no need for a bunch of related code, that were not even being used, as code using these perf_env methods was also enclosed in HAVE_LIBBPF_SUPPORT. Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Align buildid list output for short build ids

2020-10-14T14:28:52+00:00

With shorter md5 build ids we need to align their paths properly with other build ids: $ perf buildid-list 17f4e448cc746582ea1881528deb549f7fdb3fd5 [kernel.kallsyms] a50e350e97c43b4708d09bcd85ebfff7 .../tools/perf/buildid-ex-md5 1805c738c8f3ec0f47b7ea09080c28f34d18a82b /usr/lib64/ld-2.31.so $ Signed-off-by: Jiri Olsa Acked-by: Ian Rogers Link: https://lore.kernel.org/r/20201013192441.1299447-9-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Pass build_id object to dso__build_id_equal()

2020-10-14T12:25:36+00:00

Passing build_id object to dso__build_id_equal(), so we can properly check build id with different size than sha1. Signed-off-by: Jiri Olsa Acked-by: Ian Rogers Link: https://lore.kernel.org/r/20201013192441.1299447-7-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo