[PATCH 4.2.y-ckt 164/206] perf test: Ignore kcore files in the "vmlinux matches kallsyms" test

From: Kamal Mostafa
Date: Thu Jun 09 2016 - 17:32:58 EST


4.2.8-ckt12 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

commit 53d0fe68275dbdaf6a532bb4e87f00db5d36c140 upstream.

Before:

# perf test -v kallsyms
<SNIP>
Maps only in vmlinux:
ffffffff81d5e000-ffffffff81ec3ac8 115e000 [kernel].init.text
ffffffff81ec3ac8-ffffffffa0000000 12c3ac8 [kernel].exit.text
ffffffffa0000000-ffffffffa000c000 0 [fjes]
ffffffffa000c000-ffffffffa0017000 0 [video]
ffffffffa0017000-ffffffffa001c000 0 [grace]
<SNIP>
ffffffffa0a7f000-ffffffffa0ba5000 0 [xfs]
ffffffffa0ba5000-ffffffffffffffff 0 [veth]
Maps in vmlinux with a different name in kallsyms:
Maps only in kallsyms:
ffff880000100000-ffff88001000b000 80000103000 [kernel.kallsyms]
ffff88001000b000-ffff880100000000 8001000e000 [kernel.kallsyms]
ffff880100000000-ffffc90000000000 80100003000 [kernel.kallsyms]
<SNIP>
ffffffffa0000000-ffffffffff600000 7fffa0003000 [kernel.kallsyms]
ffffffffff600000-ffffffffffffffff 7fffff603000 [kernel.kallsyms]
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
#

After:

# perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 7058
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.6.0-rc1+/build/vmlinux for symbols
0xffffffff81076870: diff end addr for aesni_gcm_dec v: 0xffffffff810791f2 k: 0xffffffff81076902
0xffffffff81079200: diff end addr for aesni_gcm_enc v: 0xffffffff8107bb03 k: 0xffffffff81079292
0xffffffff8107e8d0: diff end addr for aesni_gcm_enc_avx_gen2 v: 0xffffffff81083e76 k: 0xffffffff8107e943
0xffffffff81083e80: diff end addr for aesni_gcm_dec_avx_gen2 v: 0xffffffff81089611 k: 0xffffffff81083ef3
0xffffffff81089990: diff end addr for aesni_gcm_enc_avx_gen4 v: 0xffffffff8108e7c4 k: 0xffffffff81089a03
0xffffffff8108e7d0: diff end addr for aesni_gcm_dec_avx_gen4 v: 0xffffffff810937ef k: 0xffffffff8108e843
Maps only in vmlinux:
ffffffff81d5e000-ffffffff81ec3ac8 115e000 [kernel].init.text
ffffffff81ec3ac8-ffffffffa0000000 12c3ac8 [kernel].exit.text
Maps in vmlinux with a different name in kallsyms:
Maps only in kallsyms:
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
#

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Fixes: 8e0cf965f95e ("perf symbols: Add support for reading from /proc/kcore")
Link: http://lkml.kernel.org/n/tip-n6vrwt9t89w8k769y349govx@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
tools/perf/tests/vmlinux-kallsyms.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c
index b34c5fc..8de34ea 100644
--- a/tools/perf/tests/vmlinux-kallsyms.c
+++ b/tools/perf/tests/vmlinux-kallsyms.c
@@ -54,8 +54,14 @@ int test__vmlinux_matches_kallsyms(void)
* Step 3:
*
* Load and split /proc/kallsyms into multiple maps, one per module.
+ * Do not use kcore, as this test was designed before kcore support
+ * and has parts that only make sense if using the non-kcore code.
+ * XXX: extend it to stress the kcorre code as well, hint: the list
+ * of modules extracted from /proc/kcore, in its current form, can't
+ * be compacted against the list of modules found in the "vmlinux"
+ * code and with the one got from /proc/modules from the "kallsyms" code.
*/
- if (machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, NULL) <= 0) {
+ if (__machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, true, NULL) <= 0) {
pr_debug("dso__load_kallsyms ");
goto out;
}
--
2.7.4