Re: [PATCH 3/6] perf probe: Add supported type casting of running kernel

Arnaldo Carvalho de Melo
2016-08-23T19:45:54Z

Em Thu, Aug 18, 2016 at 05:58:31PM +0900, Masami Hiramatsu escreveu:
> Add a checking routine what types are supported by the
> running kernel by finding the pattern in
> <debugfs>/tracing/README.

Fails in several distros, I'm fixing it:

# time dm
1 67.863552726 alpine:3.4: Ok
2 26.710853767 android-ndk:r12b-arm: Ok
3 72.985361634 archlinux:latest: Ok
4 19.637909096 centos:5: FAIL
CC /tmp/build/perf/util/probe-event.o
cc1: warnings being treated as errors
util/probe-file.c: In function 'probe_type_is_available':
util/probe-file.c:904: warning: comparison of unsigned expression < 0 is always false
mv: cannot stat `/tmp/build/perf/util/.probe-file.o.tmp': No such file or directory
make[3]: *** [/tmp/build/perf/util/probe-file.o] Error 1
make[3]: *** Waiting for unfinished jobs....
5 28.720326873 centos:6: FAIL
cc1: warnings being treated as errors
util/probe-file.c: In function 'probe_type_is_available':
util/probe-file.c:904: error: comparison of unsigned expression < 0 is always false
mv: cannot stat `/tmp/build/perf/util/.probe-file.o.tmp': No such file or directory
make[3]: *** [/tmp/build/perf/util/probe-file.o] Error 1
make[3]: *** Waiting for unfinished jobs....
6 70.156507794 centos:7: Ok
7 32.013330592 debian:7: FAIL
CC /tmp/build/perf/util/probe-file.o
util/probe-file.c: In function 'probe_type_is_available':
util/probe-file.c:904:2: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits]
cc1: all warnings being treated as errors
mv: cannot stat `/tmp/build/perf/util/.probe-file.o.tmp': No such file or directory
make[3]: *** [/tmp/build/perf/util/probe-file.o] Error 1
make[3]: *** Waiting for unfinished jobs....
8 69.603178590 debian:8: Ok
9 73.783068558 debian:experimental: Ok
10 69.957097133 fedora:20: Ok
11 76.603382387 fedora:21: Ok
12 73.468157842 fedora:22: Ok
13 71.936508182 fedora:23: Ok
14 77.361195679 fedora:24: Ok
15 38.279025856 fedora:24-x-ARC-uClibc: Ok
16 97.249261355 fedora:rawhide: Ok
17 98.245080998 mageia:5: Ok
18 94.932568645 opensuse:13.2: Ok
19 75.037585460 opensuse:42.1: Ok
20 78.874088196 opensuse:tumbleweed: Ok
21 29.516286324 ubuntu:12.04.5: FAIL
CC /tmp/build/perf/util/probe-event.o
util/probe-file.c: In function 'probe_type_is_available':
util/probe-file.c:904:2: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits]
cc1: all warnings being treated as errors
mv: cannot stat `/tmp/build/perf/util/.probe-file.o.tmp': No such file or directory
make[3]: *** [/tmp/build/perf/util/probe-file.o] Error 1
make[3]: *** Waiting for unfinished jobs....
22 67.473466290 ubuntu:14.04.4: Ok
23 70.052930002 ubuntu:15.10: Ok
24 73.910662998 ubuntu:16.04: Ok
25 58.592432948 ubuntu:16.04-x-arm: Ok
26 53.732729132 ubuntu:16.04-x-arm64: Ok
27 53.279460667 ubuntu:16.04-x-powerpc64: Ok
28 53.933970903 ubuntu:16.04-x-powerpc64el: Ok
29 73.724853906 ubuntu:16.10: Ok
30 55.651095622 ubuntu:16.10-x-s390: Ok

> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> tools/perf/util/probe-file.c | 57 ++++++++++++++++++++++++++++++++++++++++
> tools/perf/util/probe-file.h | 10 +++++++
> tools/perf/util/probe-finder.c | 1 +
> 3 files changed, 68 insertions(+)
>
> diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
> index 9aed9c3..552e56b 100644
> --- a/tools/perf/util/probe-file.c
> +++ b/tools/perf/util/probe-file.c
> @@ -855,3 +855,60 @@ int probe_cache__show_all_caches(struct strfilter *filter)
>
> return 0;
> }
> +
> +static struct {
> + const char *pattern;
> + bool avail;
> + bool checked;
> +} probe_type_table[] = {
> +#define DEFINE_TYPE(idx, pat, def_avail) \
> + [idx] = {.pattern = pat, .avail = (def_avail)}
> + DEFINE_TYPE(PROBE_TYPE_U, "* u8/16/32/64,*", true),
> + DEFINE_TYPE(PROBE_TYPE_S, "* s8/16/32/64,*", true),
> + DEFINE_TYPE(PROBE_TYPE_X, "* x8/16/32/64,*", false),
> + DEFINE_TYPE(PROBE_TYPE_STRING, "* string,*", true),
> + DEFINE_TYPE(PROBE_TYPE_BITFIELD,
> + "* b<bit-width>@<bit-offset>/<container-size>", true),
> +};
> +
> +bool probe_type_is_available(enum probe_type type)
> +{
> + FILE *fp;
> + char *buf = NULL;
> + size_t len = 0;
> + bool target_line = false;
> + bool ret = probe_type_table[type].avail;
> +
> + if (type < 0 || type >= PROBE_TYPE_END)
> + return false;
> + /* We don't have to check the type which supported by default */
> + if (ret || probe_type_table[type].checked)
> + return ret;
> +
> + if (asprintf(&buf, "%s/README", tracing_path) < 0)
> + return ret;
> +
> + fp = fopen(buf, "r");
> + if (!fp)
> + goto end;
> +
> + zfree(&buf);
> + while (getline(&buf, &len, fp) > 0 && !ret) {
> + if (!target_line) {
> + target_line = !!strstr(buf, " type: ");
> + if (!target_line)
> + continue;
> + } else if (strstr(buf, "\t ") != buf)
> + break;
> + ret = strglobmatch(buf, probe_type_table[type].pattern);
> + }
> + /* Cache the result */
> + probe_type_table[type].checked = true;
> + probe_type_table[type].avail = ret;
> +
> + fclose(fp);
> +end:
> + free(buf);
> +
> + return ret;
> +}
> diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
> index 9577b5c..eba44c3 100644
> --- a/tools/perf/util/probe-file.h
> +++ b/tools/perf/util/probe-file.h
> @@ -19,6 +19,15 @@ struct probe_cache {
> struct list_head entries;
> };
>
> +enum probe_type {
> + PROBE_TYPE_U = 0,
> + PROBE_TYPE_S,
> + PROBE_TYPE_X,
> + PROBE_TYPE_STRING,
> + PROBE_TYPE_BITFIELD,
> + PROBE_TYPE_END,
> +};
> +
> #define PF_FL_UPROBE 1
> #define PF_FL_RW 2
> #define for_each_probe_cache_entry(entry, pcache) \
> @@ -54,6 +63,7 @@ struct probe_cache_entry *probe_cache__find(struct probe_cache *pcache,
> struct probe_cache_entry *probe_cache__find_by_name(struct probe_cache *pcache,
> const char *group, const char *event);
> int probe_cache__show_all_caches(struct strfilter *filter);
> +bool probe_type_is_available(enum probe_type type);
> #else /* ! HAVE_LIBELF_SUPPORT */
> static inline struct probe_cache *probe_cache__new(const char *tgt __maybe_unused)
> {
> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> index 5c290c6..24dbe23 100644
> --- a/tools/perf/util/probe-finder.c
> +++ b/tools/perf/util/probe-finder.c
> @@ -39,6 +39,7 @@
> #include "util.h"
> #include "symbol.h"
> #include "probe-finder.h"
> +#include "probe-file.h"
>
> /* Kprobe tracer basic type is up to u64 */
> #define MAX_BASIC_TYPE_BITS 64