diff options
| author | Dave Martin <dave.martin@linaro.org> | 2010-08-03 11:49:01 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2010-08-03 14:12:09 +0100 |
| commit | 224a2106f63943b3194b2080bdf938ea94fe8d22 (patch) | |
| tree | 40c06c9c792ea564cd13e32a38e57aafdd0c0a30 /tools | |
| parent | 17c507ba926e4272d9ef077b6bfa256b7a85324a (diff) | |
perf symbols: work around incorrect ET_EXEC symbol adjustment
Workaround to adjust .text symbols from ET_EXEC images correctly.
This is not a complete fix, but addresses the common case and does not
create additional assumptions beyond those which perf already makes.
ELF images with a weird link map may still be processed incorrectly
(as at present) -- that will require a separate fix.
The workaround allows correct symbol offsets to be generated for
ET_EXEC executables on systems with separated debug info (where
section sh_offset fields from the debug image may bear no relation to
the layout of the executable image).
The cover note accompanying this patch contains a more detailed
explanation.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/symbol.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index d80346d0d05..c991525908b 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1093,7 +1093,15 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name, "sh_addr: %#Lx sh_offset: %#Lx\n", __func__, (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset); - sym.st_value -= shdr.sh_addr - shdr.sh_offset; + /* Assumptions: + * a) shdr.sh_addr - shdr.sh_offset == + * map->start - map->pgoff + * b) map->pgoff == 0 + * These are true iff we are looking at a function + * symbol in the main executable segment _and_ + * the main executable segment starts at the start of + * the ELF image (normally true). */ + sym.st_value -= map->start; } /* * We need to figure out if the object was created from C++ sources |