[PATCH v3 6/6] perf symbols: Kill dso__build_id_is_kmod()

From: Namhyung Kim
Date: Wed Jun 07 2017 - 11:40:22 EST


The commit e7ee40475760 ("perf symbols: Fix symbols searching for module
in buildid-cache") added the function to check kernel modules reside in
the build-id cache. This was because there's no way to identify a DSO
which is actually a kernel module. So it searched linkname of the file
and find ".ko" suffix.

But this does not work for compressed kernel modules and now such DSOs
have correct symtab_type now. So no need to check it anymore. This
patch essentially reverts the commit.

Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/build-id.c | 45 ---------------------------------------------
tools/perf/util/build-id.h | 1 -
tools/perf/util/symbol.c | 4 ----
3 files changed, 50 deletions(-)

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 168cc49654e7..e0148b081bdf 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -278,51 +278,6 @@ char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
return bf;
}

-bool dso__build_id_is_kmod(const struct dso *dso, char *bf, size_t size)
-{
- char *id_name = NULL, *ch;
- struct stat sb;
- char sbuild_id[SBUILD_ID_SIZE];
-
- if (!dso->has_build_id)
- goto err;
-
- build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
- id_name = build_id_cache__linkname(sbuild_id, NULL, 0);
- if (!id_name)
- goto err;
- if (access(id_name, F_OK))
- goto err;
- if (lstat(id_name, &sb) == -1)
- goto err;
- if ((size_t)sb.st_size > size - 1)
- goto err;
- if (readlink(id_name, bf, size - 1) < 0)
- goto err;
-
- bf[sb.st_size] = '\0';
-
- /*
- * link should be:
- * ../../lib/modules/4.4.0-rc4/kernel/net/ipv4/netfilter/nf_nat_ipv4.ko/a09fe3eb3147dafa4e3b31dbd6257e4d696bdc92
- */
- ch = strrchr(bf, '/');
- if (!ch)
- goto err;
- if (ch - 3 < bf)
- goto err;
-
- free(id_name);
- return strncmp(".ko", ch - 3, 3) == 0;
-err:
- pr_err("Invalid build id: %s\n", id_name ? :
- dso->long_name ? :
- dso->short_name ? :
- "[unknown]");
- free(id_name);
- return false;
-}
-
#define dsos__for_each_with_build_id(pos, head) \
list_for_each_entry(pos, head, node) \
if (!pos->has_build_id) \
diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h
index 8a89b195c1fc..96690a55c62c 100644
--- a/tools/perf/util/build-id.h
+++ b/tools/perf/util/build-id.h
@@ -17,7 +17,6 @@ char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
size_t size);

char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size);
-bool dso__build_id_is_kmod(const struct dso *dso, char *bf, size_t size);

int build_id__mark_dso_hit(struct perf_tool *tool, union perf_event *event,
struct perf_sample *sample, struct perf_evsel *evsel,
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 8f2b068ff756..e7a98dbd2aed 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1562,10 +1562,6 @@ int dso__load(struct dso *dso, struct map *map)
if (!runtime_ss && syms_ss)
runtime_ss = syms_ss;

- if (syms_ss && syms_ss->type == DSO_BINARY_TYPE__BUILD_ID_CACHE)
- if (dso__build_id_is_kmod(dso, name, PATH_MAX))
- kmod = true;
-
if (syms_ss)
ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
else
--
2.13.0