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author | Namhyung Kim <namhyung@kernel.org> | 2023-12-11 23:05:45 -0800 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2023-12-14 19:08:48 -0300 |
commit | c966d23a351a33f8a977fd7efbb6f467132f7383 (patch) | |
tree | 0e1025b493da6694e8e15f928cc0f650a9f36161 /tools/perf/util/unwind-libdw.c | |
parent | perf genelf: Set ELF program header addresses properly (diff) | |
download | wireguard-linux-c966d23a351a33f8a977fd7efbb6f467132f7383.tar.xz wireguard-linux-c966d23a351a33f8a977fd7efbb6f467132f7383.zip |
perf unwind-libdw: Handle JIT-generated DSOs properly
Usually DSOs are mapped from the beginning of the file, so the base
address of the DSO can be calculated by map->start - map->pgoff.
However, JIT DSOs which are generated by `perf inject -j`, are mapped
only the code segment. This makes unwind-libdw code confusing and
rejects processing unwinds in the JIT DSOs. It should use the map
start address as base for them to fix the confusion.
Fixes: 1fe627da30331024 ("perf unwind: Take pgoff into account when reporting elf to libdwfl")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Pablo Galindo <pablogsal@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231212070547.612536-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/unwind-libdw.c')
-rw-r--r-- | tools/perf/util/unwind-libdw.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c index 8554db3fc0d7..6013335a8dae 100644 --- a/tools/perf/util/unwind-libdw.c +++ b/tools/perf/util/unwind-libdw.c @@ -46,6 +46,7 @@ static int __report_module(struct addr_location *al, u64 ip, { Dwfl_Module *mod; struct dso *dso = NULL; + Dwarf_Addr base; /* * Some callers will use al->sym, so we can't just use the * cheaper thread__find_map() here. @@ -58,13 +59,25 @@ static int __report_module(struct addr_location *al, u64 ip, if (!dso) return 0; + /* + * The generated JIT DSO files only map the code segment without + * ELF headers. Since JIT codes used to be packed in a memory + * segment, calculating the base address using pgoff falls into + * a different code in another DSO. So just use the map->start + * directly to pick the correct one. + */ + if (!strncmp(dso->long_name, "/tmp/jitted-", 12)) + base = map__start(al->map); + else + base = map__start(al->map) - map__pgoff(al->map); + mod = dwfl_addrmodule(ui->dwfl, ip); if (mod) { Dwarf_Addr s; dwfl_module_info(mod, NULL, &s, NULL, NULL, NULL, NULL, NULL); - if (s != map__start(al->map) - map__pgoff(al->map)) - mod = 0; + if (s != base) + mod = NULL; } if (!mod) { @@ -72,14 +85,14 @@ static int __report_module(struct addr_location *al, u64 ip, __symbol__join_symfs(filename, sizeof(filename), dso->long_name); mod = dwfl_report_elf(ui->dwfl, dso->short_name, filename, -1, - map__start(al->map) - map__pgoff(al->map), false); + base, false); } if (!mod) { char filename[PATH_MAX]; if (dso__build_id_filename(dso, filename, sizeof(filename), false)) mod = dwfl_report_elf(ui->dwfl, dso->short_name, filename, -1, - map__start(al->map) - map__pgoff(al->map), false); + base, false); } if (mod) { |