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| author | Masami Hiramatsu <mhiramat@kernel.org> | 2020-11-27 14:48:55 +0900 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-11-27 14:36:15 -0300 |
| commit | a9ffd0484eb4426e6befd07e7be6c01108716302 (patch) | |
| tree | d7a6e0370102541d04c49f0bbde673694311c809 /tools | |
| parent | ab4200c17ba6fe71d2da64317aae8a8aa684624c (diff) | |
| download | linux-a9ffd0484eb4426e6befd07e7be6c01108716302.tar.gz linux-a9ffd0484eb4426e6befd07e7be6c01108716302.tar.bz2 linux-a9ffd0484eb4426e6befd07e7be6c01108716302.zip | |
perf probe: Change function definition check due to broken DWARF
Since some gcc generates a broken DWARF which lacks DW_AT_declaration
attribute from the subprogram DIE of function prototype.
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97060)
So, in addition to the DW_AT_declaration check, we also check the
subprogram DIE has DW_AT_inline or actual entry pc.
Committer testing:
# cat /etc/fedora-release
Fedora release 33 (Thirty Three)
#
Before:
# perf test vfs_getname
78: Use vfs_getname probe to get syscall args filenames : FAILED!
79: Check open filename arg using perf trace + vfs_getname : FAILED!
81: Add vfs_getname probe to get syscall args filenames : FAILED!
#
After:
# perf test vfs_getname
78: Use vfs_getname probe to get syscall args filenames : Ok
79: Check open filename arg using perf trace + vfs_getname : Ok
81: Add vfs_getname probe to get syscall args filenames : Ok
#
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: http://lore.kernel.org/lkml/160645613571.2824037.7441351537890235895.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/dwarf-aux.c | 20 | ||||
| -rw-r--r-- | tools/perf/util/probe-finder.c | 3 |
2 files changed, 19 insertions, 4 deletions
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c index 03c1a39c312a..7b2d471a6419 100644 --- a/tools/perf/util/dwarf-aux.c +++ b/tools/perf/util/dwarf-aux.c @@ -356,9 +356,25 @@ bool die_is_signed_type(Dwarf_Die *tp_die) bool die_is_func_def(Dwarf_Die *dw_die) { Dwarf_Attribute attr; + Dwarf_Addr addr = 0; + + if (dwarf_tag(dw_die) != DW_TAG_subprogram) + return false; + + if (dwarf_attr(dw_die, DW_AT_declaration, &attr)) + return false; - return (dwarf_tag(dw_die) == DW_TAG_subprogram && - dwarf_attr(dw_die, DW_AT_declaration, &attr) == NULL); + /* + * DW_AT_declaration can be lost from function declaration + * by gcc's bug #97060. + * So we need to check this subprogram DIE has DW_AT_inline + * or an entry address. + */ + if (!dwarf_attr(dw_die, DW_AT_inline, &attr) && + die_entrypc(dw_die, &addr) < 0) + return false; + + return true; } /** diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 2c4061035f77..76dd349aa48d 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -1885,8 +1885,7 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data) if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die))) return DWARF_CB_OK; - if (die_is_func_def(sp_die) && - die_match_name(sp_die, lr->function)) { + if (die_match_name(sp_die, lr->function) && die_is_func_def(sp_die)) { lf->fname = dwarf_decl_file(sp_die); dwarf_decl_line(sp_die, &lr->offset); pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset); |