2009-11-16 15:48:17

by Arnaldo Carvalho de Melo

Subject: [PATCH 1/1] perf symbols: Call the symbol filter in dso__synthesize_plt_symbols

From: Arnaldo Carvalho de Melo <[email protected]>

We need to pass the symbol to the filter so that, for instance, 'perf
top' can do filtering and also set the private area it manages, setting
the ->map pointer, etc.

I found this while running 'perf top' on a machine where hits happened
on PLT symbols, where ->map wasn't being set up and segfaults thus
happened.

Cc: Frederic Weisbecker <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/symbol.c | 26 ++++++++++++++++++++------
1 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 9c286db..93e4b52 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -281,6 +281,11 @@ static int kernel_maps__load_all_kallsyms(void)
if (sym == NULL)
goto out_delete_line;

+ /*
+ * We will pass the symbols to the filter later, in
+ * kernel_maps__split_kallsyms, when we have split the
+ * maps per module
+ */
dso__insert_symbol(kernel_map->dso, sym);
}

@@ -555,7 +560,8 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
* And always look at the original dso, not at debuginfo packages, that
* have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
*/
-static int dso__synthesize_plt_symbols(struct dso *self)
+static int dso__synthesize_plt_symbols(struct dso *self, struct map *map,
+ symbol_filter_t filter)
{
uint32_t nr_rel_entries, idx;
GElf_Sym sym;
@@ -643,8 +649,12 @@ static int dso__synthesize_plt_symbols(struct dso *self)
if (!f)
goto out_elf_end;

- dso__insert_symbol(self, f);
- ++nr;
+ if (filter && filter(map, f))
+ symbol__delete(f);
+ else {
+ dso__insert_symbol(self, f);
+ ++nr;
+ }
}
} else if (shdr_rel_plt.sh_type == SHT_REL) {
GElf_Rel pos_mem, *pos;
@@ -661,8 +671,12 @@ static int dso__synthesize_plt_symbols(struct dso *self)
if (!f)
goto out_elf_end;

- dso__insert_symbol(self, f);
- ++nr;
+ if (filter && filter(map, f))
+ symbol__delete(f);
+ else {
+ dso__insert_symbol(self, f);
+ ++nr;
+ }
}
}

@@ -1050,7 +1064,7 @@ compare_build_id:
goto more;

if (ret > 0) {
- int nr_plt = dso__synthesize_plt_symbols(self);
+ int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
if (nr_plt > 0)
ret += nr_plt;
}
--
1.6.2.5

2009-11-16 16:48:17

by Arnaldo Carvalho de Melo

Subject: [tip:perf/core] perf symbols: Call the symbol filter in dso__synthesize_plt_symbols()

Commit-ID: 82164161679c448f33092945ea97cb547a13683a
Gitweb: http://git.kernel.org/tip/82164161679c448f33092945ea97cb547a13683a
Author: Arnaldo Carvalho de Melo <[email protected]>
AuthorDate: Mon, 16 Nov 2009 13:48:11 -0200
Committer: Ingo Molnar <[email protected]>
CommitDate: Mon, 16 Nov 2009 17:29:54 +0100

perf symbols: Call the symbol filter in dso__synthesize_plt_symbols()

We need to pass the symbol to the filter so that, for instance,
'perf top' can do filtering and also set the private area it
manages, setting the ->map pointer, etc.

I found this while running 'perf top' on a machine where hits
happened on PLT symbols, where ->map wasn't being set up and
segfaults thus happened.

Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Peter Zijlstra <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
---
tools/perf/util/symbol.c | 26 ++++++++++++++++++++------
1 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 9c286db..93e4b52 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -281,6 +281,11 @@ static int kernel_maps__load_all_kallsyms(void)
if (sym == NULL)
goto out_delete_line;

+ /*
+ * We will pass the symbols to the filter later, in
+ * kernel_maps__split_kallsyms, when we have split the
+ * maps per module
+ */
dso__insert_symbol(kernel_map->dso, sym);
}

@@ -555,7 +560,8 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
* And always look at the original dso, not at debuginfo packages, that
* have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
*/
-static int dso__synthesize_plt_symbols(struct dso *self)
+static int dso__synthesize_plt_symbols(struct dso *self, struct map *map,
+ symbol_filter_t filter)
{
uint32_t nr_rel_entries, idx;
GElf_Sym sym;
@@ -643,8 +649,12 @@ static int dso__synthesize_plt_symbols(struct dso *self)
if (!f)
goto out_elf_end;

- dso__insert_symbol(self, f);
- ++nr;
+ if (filter && filter(map, f))
+ symbol__delete(f);
+ else {
+ dso__insert_symbol(self, f);
+ ++nr;
+ }
}
} else if (shdr_rel_plt.sh_type == SHT_REL) {
GElf_Rel pos_mem, *pos;
@@ -661,8 +671,12 @@ static int dso__synthesize_plt_symbols(struct dso *self)
if (!f)
goto out_elf_end;

- dso__insert_symbol(self, f);
- ++nr;
+ if (filter && filter(map, f))
+ symbol__delete(f);
+ else {
+ dso__insert_symbol(self, f);
+ ++nr;
+ }
}
}

@@ -1050,7 +1064,7 @@ compare_build_id:
goto more;

if (ret > 0) {
- int nr_plt = dso__synthesize_plt_symbols(self);
+ int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
if (nr_plt > 0)
ret += nr_plt;
}