I.e. we can't handle these two kinds of files in the same way:
1) prelinked system library:
[acme@doppio pahole]$ readelf -s /usr/lib64/libdw-0.141.so | egrep 'FUNC.+GLOBAL.+dwfl_report_elf'
278: 00000030450105a0 261 FUNC GLOBAL DEFAULT 12 dwfl_report_elf@@ELFUTILS_0.122
2) not prelinked library with debug information from a -debuginfo package:
[acme@doppio pahole]$ readelf -s /usr/lib/debug/usr/lib64/libdw-0.141.so.debug | egrep 'FUNC.+GLOBAL.+dwfl_report_elf'
629: 00000000000105a0 261 FUNC GLOBAL DEFAULT 12 dwfl_report_elf
[acme@doppio pahole]$
Now the numbers I got for a pahole perf run are in line with the numbers I get
from oprofile.
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 9c659ef..78c2efd 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -520,7 +520,9 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
nr_syms = shdr.sh_size / shdr.sh_entsize;
memset(&sym, 0, sizeof(sym));
-
+ self->prelinked = elf_section_by_name(elf, &ehdr, &shdr,
+ ".gnu.prelink_undo",
+ NULL) != NULL;
elf_symtab__for_each_symbol(syms, nr_syms, index, sym) {
struct symbol *f;
u64 obj_start;
@@ -535,11 +537,13 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
gelf_getshdr(sec, &shdr);
obj_start = sym.st_value;
- if (verbose >= 2)
- printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
- (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
+ if (self->prelinked) {
+ if (verbose >= 2)
+ printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
+ (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
- sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ }
f = symbol__new(sym.st_value, sym.st_size,
elf_sym__name(&sym, symstrs),
@@ -573,6 +577,8 @@ int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
if (!name)
return -1;
+ self->prelinked = 0;
+
if (strncmp(self->name, "/tmp/perf-", 10) == 0)
return dso__load_perf_map(self, filter, verbose);
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 940b432..9751667 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -20,8 +20,9 @@ struct symbol {
struct dso {
struct list_head node;
struct rb_root syms;
- unsigned int sym_priv_size;
struct symbol *(*find_symbol)(struct dso *, u64 ip);
+ unsigned int sym_priv_size;
+ unsigned char prelinked:1;
char name[0];
};
Commit-ID: f5812a7a336fb952d819e4427b9a2dce02368e82
Gitweb: http://git.kernel.org/tip/f5812a7a336fb952d819e4427b9a2dce02368e82
Author: Arnaldo Carvalho de Melo <[email protected]>
AuthorDate: Tue, 30 Jun 2009 11:43:17 -0300
Committer: Ingo Molnar <[email protected]>
CommitDate: Tue, 30 Jun 2009 17:09:30 +0200
perf_counter tools: Adjust only prelinked symbol's addresses
I.e. we can't handle these two kinds of files in the same way:
1) prelinked system library:
[acme@doppio pahole]$ readelf -s /usr/lib64/libdw-0.141.so | egrep 'FUNC.+GLOBAL.+dwfl_report_elf'
278: 00000030450105a0 261 FUNC GLOBAL DEFAULT 12 dwfl_report_elf@@ELFUTILS_0.122
2) not prelinked library with debug information from a -debuginfo package:
[acme@doppio pahole]$ readelf -s /usr/lib/debug/usr/lib64/libdw-0.141.so.debug | egrep 'FUNC.+GLOBAL.+dwfl_report_elf'
629: 00000000000105a0 261 FUNC GLOBAL DEFAULT 12 dwfl_report_elf
[acme@doppio pahole]$
Now the numbers I got for a pahole perf run are in line with
the numbers I get from oprofile.
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
tools/perf/util/symbol.c | 16 +++++++++++-----
tools/perf/util/symbol.h | 3 ++-
2 files changed, 13 insertions(+), 6 deletions(-)
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 9c659ef..78c2efd 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -520,7 +520,9 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
nr_syms = shdr.sh_size / shdr.sh_entsize;
memset(&sym, 0, sizeof(sym));
-
+ self->prelinked = elf_section_by_name(elf, &ehdr, &shdr,
+ ".gnu.prelink_undo",
+ NULL) != NULL;
elf_symtab__for_each_symbol(syms, nr_syms, index, sym) {
struct symbol *f;
u64 obj_start;
@@ -535,11 +537,13 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
gelf_getshdr(sec, &shdr);
obj_start = sym.st_value;
- if (verbose >= 2)
- printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
- (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
+ if (self->prelinked) {
+ if (verbose >= 2)
+ printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
+ (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
- sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ }
f = symbol__new(sym.st_value, sym.st_size,
elf_sym__name(&sym, symstrs),
@@ -573,6 +577,8 @@ int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
if (!name)
return -1;
+ self->prelinked = 0;
+
if (strncmp(self->name, "/tmp/perf-", 10) == 0)
return dso__load_perf_map(self, filter, verbose);
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 940b432..2c48ace 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -20,8 +20,9 @@ struct symbol {
struct dso {
struct list_head node;
struct rb_root syms;
- unsigned int sym_priv_size;
struct symbol *(*find_symbol)(struct dso *, u64 ip);
+ unsigned int sym_priv_size;
+ unsigned char prelinked;
char name[0];
};