On 31/07/2013 8:28 p.m., Arnaldo Carvalho de Melo wrote:
Em Wed, Jul 31, 2013 at 11:58:20AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, Jul 31, 2013 at 12:13:50AM +0300, Adrian Hunter escreveu:
> > Using the information in mmap events, perf tools can read object
> > code associated with sampled addresses. A test is added that
> > compares bytes read by perf with the same bytes read using
> > objdump.
>
> investigating...
>
> (gdb) run test 21
> Starting program: /root/bin/perf test 21
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib64/libthread_db.so.1".
> 21: Test object code reading :
> Program received signal SIGSEGV, Segmentation fault.
> 0x000000000045a2d3 in xyarray__entry (xy=0x0, x=0, y=0) at util/xyarray.h:17
> 17 return&xy->contents[x * xy->row_size + y * xy->entry_size];
Still investigating, but the attached patch is needed to handle such
failure cases:
I removed the offending perf_evlist__disable() since it was not needed
anyway. Otherwise the existing error path was simpler so I kept it in V3.
[root@zoo ~]# perf test 21
21: Test object code reading : FAILED!
[root@zoo ~]# perf test -v 21
21: Test object code reading :
--- start ---
Looking at the vmlinux_path (6 entries long)
symsrc__init: cannot get elf header.
Using /lib/modules/3.11.0-rc2+/build/vmlinux for symbols
Parsing event 'cycles'
Parsing event 'cycles:u'
perf_evlist__open failed
---- end ----
Test object code reading: FAILED!
[root@zoo ~]#
- Arnaldo
error_path.patch
diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 7c9437d..9d9b6b5 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -357,7 +357,7 @@ static int do_test_code_reading(void)
ret = machine__create_kernel_maps(machine);
if (ret< 0) {
pr_debug("machine__create_kernel_maps failed\n");
- goto out_err;
+ goto out_machine_exit;
}
/* Load kernel map */
@@ -365,7 +365,7 @@ static int do_test_code_reading(void)
ret = map__load(map, NULL);
if (ret< 0) {
pr_debug("map__load failed\n");
- goto out_err;
+ goto out_destroy_kernel_maps;
}
have_vmlinux = map->dso->symtab_type == DSO_BINARY_TYPE__VMLINUX;
/* No point getting kernel events if there is no vmlinux */
@@ -375,26 +375,26 @@ static int do_test_code_reading(void)
threads = thread_map__new_by_tid(pid);
if (!threads) {
pr_debug("thread_map__new_by_tid failed\n");
- goto out_err;
+ goto out_destroy_kernel_maps;
}
ret = perf_event__synthesize_thread_map(NULL, threads,
perf_event__process, machine);
if (ret< 0) {
pr_debug("perf_event__synthesize_thread_map failed\n");
- goto out_err;
+ goto out_thread_map_delete;
}
thread = machine__findnew_thread(machine, pid);
if (!thread) {
pr_debug("machine__findnew_thread failed\n");
- goto out_err;
+ goto out_thread_map_delete;
}
cpus = cpu_map__new(NULL);
if (!cpus) {
pr_debug("cpu_map__new failed\n");
- goto out_err;
+ goto out_thread_map_delete;
}
while (1) {
@@ -403,7 +403,7 @@ static int do_test_code_reading(void)
evlist = perf_evlist__new();
if (!evlist) {
pr_debug("perf_evlist__new failed\n");
- goto out_err;
+ goto out_cpu_map_delete;
}
perf_evlist__set_maps(evlist, cpus, threads);
@@ -416,7 +416,7 @@ static int do_test_code_reading(void)
ret = parse_events(evlist, str);
if (ret< 0) {
pr_debug("parse_events failed\n");
- goto out_err;
+ goto out_evlist_delete;
}
perf_evlist__config(evlist,&opts);
@@ -435,7 +435,7 @@ static int do_test_code_reading(void)
continue;
}
pr_debug("perf_evlist__open failed\n");
- goto out_err;
+ goto out_evlist_delete;
}
break;
}
@@ -443,7 +443,7 @@ static int do_test_code_reading(void)
ret = perf_evlist__mmap(evlist, UINT_MAX, false);
if (ret< 0) {
pr_debug("perf_evlist__mmap failed\n");
- goto out_err;
+ goto out_evlist_close;
}
perf_evlist__enable(evlist);
@@ -454,7 +454,7 @@ static int do_test_code_reading(void)
ret = process_events(machine, evlist);
if (ret< 0)
- goto out_err;
+ goto out_evlist_munmap;
if (!have_vmlinux)
err = TEST_CODE_READING_NO_VMLINUX;
@@ -462,19 +462,21 @@ static int do_test_code_reading(void)
err = TEST_CODE_READING_NO_ACCESS;
else
err = TEST_CODE_READING_OK;
-out_err:
- if (evlist) {
- perf_evlist__disable(evlist);
- perf_evlist__munmap(evlist);
- perf_evlist__close(evlist);
- perf_evlist__delete(evlist);
- }
- if (cpus)
- cpu_map__delete(cpus);
- if (threads)
- thread_map__delete(threads);
+
+out_evlist_munmap:
+ perf_evlist__munmap(evlist);
+out_evlist_close:
+ perf_evlist__close(evlist);
+out_evlist_delete:
+ perf_evlist__delete(evlist);
+out_cpu_map_delete:
+ cpu_map__delete(cpus);
+out_thread_map_delete:
+ thread_map__delete(threads);
+out_destroy_kernel_maps:
machines__destroy_kernel_maps(&machines);
machine__delete_threads(machine);
+out_machine_exit:
machines__exit(&machines);
return err;
--
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