[PATCH 8/9] perf tools: Implement addr2line directly using libbfd

From: Namhyung Kim
Date: Wed Sep 11 2013 - 01:09:44 EST


From: Roberto Vitillo <ravitillo@xxxxxxx>

When the srcline sort key is used , the external addr2line utility
needs to be run for each hist entry to get the srcline info. This can
consume quite a time if one has a huge perf.data file.

So rather than executing the external utility, implement it internally
and just call it. We can do it since we've linked with libbfd
already.

Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Roberto Agostino Vitillo <ravitillo@xxxxxxx>
[namhyung@xxxxxxxxxx: Use a2l_data struct instead of static globals]
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/config/Makefile | 4 ++
tools/perf/util/srcline.c | 167 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 171 insertions(+)

diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index 214e17e97e5c..128d580ca397 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -396,6 +396,10 @@ else
endif
endif

+ifndef ($(filter -lbfd,$(EXTLIBS)),)
+ CFLAGS += -DLIBBFD_SUPPORT
+endif
+
ifndef NO_STRLCPY
ifeq ($(call try-cc,$(SOURCE_STRLCPY),,-DHAVE_STRLCPY),y)
CFLAGS += -DHAVE_STRLCPY
diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index dcff10bed7da..10983a92bb5e 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -8,6 +8,172 @@
#include "util/util.h"
#include "util/debug.h"

+#ifdef LIBBFD_SUPPORT
+
+/*
+ * Implement addr2line using libbfd.
+ */
+#define PACKAGE "perf"
+#include <bfd.h>
+
+struct a2l_data {
+ const char *input;
+ unsigned long addr;
+
+ bool found;
+ const char *filename;
+ const char *funcname;
+ unsigned line;
+
+ bfd *abfd;
+ asymbol **syms;
+};
+
+static int bfd_error(const char *string)
+{
+ const char *errmsg;
+
+ errmsg = bfd_errmsg(bfd_get_error());
+ fflush(stdout);
+
+ if (string)
+ pr_debug("%s: %s\n", string, errmsg);
+ else
+ pr_debug("%s\n", errmsg);
+
+ return -1;
+}
+
+static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
+{
+ long storage;
+ long symcount;
+ asymbol **syms;
+ bfd_boolean dynamic = FALSE;
+
+ if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
+ return bfd_error(bfd_get_filename(abfd));
+
+ storage = bfd_get_symtab_upper_bound(abfd);
+ if (storage == 0L) {
+ storage = bfd_get_dynamic_symtab_upper_bound(abfd);
+ dynamic = TRUE;
+ }
+ if (storage < 0L)
+ return bfd_error(bfd_get_filename(abfd));
+
+ syms = malloc(storage);
+ if (dynamic)
+ symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
+ else
+ symcount = bfd_canonicalize_symtab(abfd, syms);
+
+ if (symcount < 0) {
+ free(syms);
+ return bfd_error(bfd_get_filename(abfd));
+ }
+
+ a2l->syms = syms;
+ return 0;
+}
+
+static void find_address_in_section(bfd *abfd, asection *section, void *data)
+{
+ bfd_vma pc, vma;
+ bfd_size_type size;
+ struct a2l_data *a2l = data;
+
+ if (a2l->found)
+ return;
+
+ if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0)
+ return;
+
+ pc = a2l->addr;
+ vma = bfd_get_section_vma(abfd, section);
+ size = bfd_get_section_size(section);
+
+ if (pc < vma || pc >= vma + size)
+ return;
+
+ a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
+ &a2l->filename, &a2l->funcname,
+ &a2l->line);
+}
+
+static struct a2l_data *addr2line_init(const char *path)
+{
+ bfd *abfd;
+ struct a2l_data *a2l = NULL;
+
+ abfd = bfd_openr(path, NULL);
+ if (abfd == NULL)
+ return NULL;
+
+ if (!bfd_check_format(abfd, bfd_object))
+ goto out;
+
+ a2l = zalloc(sizeof(*a2l));
+ if (a2l == NULL)
+ goto out;
+
+ a2l->abfd = abfd;
+ a2l->input = strdup(path);
+ if (a2l->input == NULL)
+ goto out;
+
+ if (slurp_symtab(abfd, a2l))
+ goto out;
+
+ return a2l;
+
+out:
+ if (a2l) {
+ free((void *)a2l->input);
+ free(a2l);
+ }
+ bfd_close(abfd);
+ return NULL;
+}
+
+static void addr2line_cleanup(struct a2l_data *a2l)
+{
+ if (a2l->abfd)
+ bfd_close(a2l->abfd);
+ free((void *)a2l->input);
+ free(a2l->syms);
+ free(a2l);
+}
+
+static int addr2line(const char *dso_name, unsigned long addr,
+ char **file, unsigned int *line)
+{
+ int ret = 0;
+ struct a2l_data *a2l;
+
+ a2l = addr2line_init(dso_name);
+ if (a2l == NULL) {
+ pr_warning("addr2line_init failed for %s\n", dso_name);
+ return 0;
+ }
+
+ a2l->addr = addr;
+ bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
+
+ if (a2l->found && a2l->filename) {
+ *file = strdup(a2l->filename);
+ *line = a2l->line;
+
+ if (*file)
+ ret = 1;
+ }
+
+ addr2line_cleanup(a2l);
+ return ret;
+}
+
+#else /* LIBBFD_SUPPORT */
+
static int addr2line(const char *dso_name, unsigned long addr,
char **file, unsigned int *line_nr)
{
@@ -53,6 +219,7 @@ out:
pclose(fp);
return ret;
}
+#endif /* LIBBFD_SUPPORT */

char *get_srcline(struct dso *dso, unsigned long addr)
{
--
1.7.11.7

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