[PATCH 17/41] perf tools: Record whether a dso is 64-bit

From: Adrian Hunter
Date: Mon Jul 14 2014 - 06:05:55 EST


Add a flag to 'struct dso' to record if the dso is 64-bit
or not. Update the flag when reading the ELF.

This is needed for instruction decoding. For
example, x86 instruction decoding depends on
whether or not the 64-bit instruction set is
used.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
tools/perf/util/dso.c | 1 +
tools/perf/util/dso.h | 1 +
tools/perf/util/symbol-elf.c | 3 +++
tools/perf/util/symbol-minimal.c | 22 ++++++++++++++++++++++
tools/perf/util/symbol.c | 1 +
tools/perf/util/symbol.h | 1 +
6 files changed, 29 insertions(+)

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 819f104..fc006fe 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -703,6 +703,7 @@ struct dso *dso__new(const char *name)
dso->data.fd = -1;
dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->binary_type = DSO_BINARY_TYPE__NOT_FOUND;
+ dso->is_64_bit = (sizeof(void *) == 8);
dso->loaded = 0;
dso->rel = 0;
dso->sorted_by_name = 0;
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index ad553ba..c239e86 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -90,6 +90,7 @@ struct dso {
u8 annotate_warned:1;
u8 short_name_allocated:1;
u8 long_name_allocated:1;
+ u8 is_64_bit:1;
u8 sorted_by_name;
u8 loaded;
u8 rel;
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 477596c..84f5e2a 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -599,6 +599,8 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
goto out_elf_end;
}

+ ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64);
+
ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab",
NULL);
if (ss->symshdr.sh_type != SHT_SYMTAB)
@@ -699,6 +701,7 @@ int dso__load_sym(struct dso *dso, struct map *map,
bool remap_kernel = false, adjust_kernel_syms = false;

dso->symtab_type = syms_ss->type;
+ dso->is_64_bit = syms_ss->is_64_bit;
dso->rel = syms_ss->ehdr.e_type == ET_REL;

/*
diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c
index bd15f49..101f55d 100644
--- a/tools/perf/util/symbol-minimal.c
+++ b/tools/perf/util/symbol-minimal.c
@@ -288,6 +288,23 @@ int dso__synthesize_plt_symbols(struct dso *dso __maybe_unused,
return 0;
}

+static int fd__is_64_bit(int fd)
+{
+ u8 e_ident[EI_NIDENT];
+
+ if (lseek(fd, 0, SEEK_SET))
+ return -1;
+
+ if (readn(fd, e_ident, sizeof(e_ident)) != sizeof(e_ident))
+ return -1;
+
+ if (memcmp(e_ident, ELFMAG, SELFMAG) ||
+ e_ident[EI_VERSION] != EV_CURRENT)
+ return -1;
+
+ return e_ident[EI_CLASS] == ELFCLASS64;
+}
+
int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
struct symsrc *ss,
struct symsrc *runtime_ss __maybe_unused,
@@ -295,6 +312,11 @@ int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
int kmodule __maybe_unused)
{
unsigned char *build_id[BUILD_ID_SIZE];
+ int ret;
+
+ ret = fd__is_64_bit(ss->fd);
+ if (ret >= 0)
+ dso->is_64_bit = ret;

if (filename__read_build_id(ss->name, build_id, BUILD_ID_SIZE) > 0) {
dso__set_build_id(dso, build_id);
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 7b9096f..be7b0df 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1064,6 +1064,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
&is_64_bit);
if (err)
goto out_err;
+ dso->is_64_bit = is_64_bit;

if (list_empty(&md.maps)) {
err = -EINVAL;
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 615c752..6ba8a22 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -215,6 +215,7 @@ struct symsrc {
GElf_Shdr dynshdr;

bool adjust_symbols;
+ bool is_64_bit;
#endif
};

--
1.8.3.2

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