[PATCH v2 perf,bpf 0/2] show bpf program info from perf.data header

[PATCH v2 perf,bpf 0/2] show bpf program info from perf.data header

[Song Liu]

Changes v1 -> v2:
1. Rebase on top of
  https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/commit/?h=perf/core&id=23265467966555a7c379263369362d576d513643

This set enables printing name, address, and size of bpf programs stored
in perf.data file.

Thanks!

Song Liu (2):
  perf, bpf: refactor perf_event__synthesize_one_bpf_prog()
  perf, bpf: show more BPF program info in print_bpf_prog_info()

 tools/perf/util/bpf-event.c | 102 ++++++++++++++++++++++++++----------
 tools/perf/util/bpf-event.h |  10 +++-
 tools/perf/util/header.c    |   5 +-
 3 files changed, 87 insertions(+), 30 deletions(-)

--
2.17.1

[PATCH v2 perf,bpf 1/2] perf, bpf: refactor perf_event__synthesize_one_bpf_prog()

[Song Liu]

Extract logic to create program names to synthesize_bpf_prog_name(), so
that it can be reused in header.c:print_bpf_prog_info().

This commit doesn't change the behavior.

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/perf/util/bpf-event.c | 62 +++++++++++++++++++++----------------
 1 file changed, 35 insertions(+), 27 deletions(-)

diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index 8fadd0471a9a..b615933c6a8c 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -111,6 +111,38 @@ static int perf_env__fetch_btf(struct perf_env *env,
 	return 0;
 }
 
+static int synthesize_bpf_prog_name(char *buf, int size,
+				    struct bpf_prog_info *info,
+				    struct btf *btf,
+				    u32 sub_id)
+{
+	u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
+	void *func_infos = (void *)(uintptr_t)(info->func_info);
+	u32 sub_prog_cnt = info->nr_jited_ksyms;
+	const struct bpf_func_info *finfo;
+	const char *short_name = NULL;
+	const struct btf_type *t;
+	int name_len;
+
+	name_len = snprintf(buf, size, "bpf_prog_");
+	name_len += snprintf_hex(buf + name_len, size - name_len,
+				 prog_tags[sub_id], BPF_TAG_SIZE);
+	if (btf) {
+		finfo = func_infos + sub_id * info->func_info_rec_size;
+		t = btf__type_by_id(btf, finfo->type_id);
+		short_name = btf__name_by_offset(btf, t->name_off);
+	} else if (sub_id == 0 && sub_prog_cnt == 1) {
+		/* no subprog */
+		if (info->name[0])
+			short_name = info->name;
+	} else
+		short_name = "F";
+	if (short_name)
+		name_len += snprintf(buf + name_len, size - name_len,
+				     "_%s", short_name);
+	return name_len;
+}
+
 /*
  * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
  * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
@@ -135,7 +167,6 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 	struct bpf_prog_info_node *info_node;
 	struct bpf_prog_info *info;
 	struct btf *btf = NULL;
-	bool has_btf = false;
 	struct perf_env *env;
 	u32 sub_prog_cnt, i;
 	int err = 0;
@@ -189,19 +220,13 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 			btf = NULL;
 			goto out;
 		}
-		has_btf = true;
 		perf_env__fetch_btf(env, info->btf_id, btf);
 	}
 
 	/* Synthesize PERF_RECORD_KSYMBOL */
 	for (i = 0; i < sub_prog_cnt; i++) {
-		u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
-		__u32 *prog_lens  = (__u32 *)(uintptr_t)(info->jited_func_lens);
+		__u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
 		__u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
-		void *func_infos  = (void *)(uintptr_t)(info->func_info);
-		const struct bpf_func_info *finfo;
-		const char *short_name = NULL;
-		const struct btf_type *t;
 		int name_len;
 
 		*ksymbol_event = (struct ksymbol_event){
@@ -214,26 +239,9 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 			.ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
 			.flags = 0,
 		};
-		name_len = snprintf(ksymbol_event->name, KSYM_NAME_LEN,
-				    "bpf_prog_");
-		name_len += snprintf_hex(ksymbol_event->name + name_len,
-					 KSYM_NAME_LEN - name_len,
-					 prog_tags[i], BPF_TAG_SIZE);
-		if (has_btf) {
-			finfo = func_infos + i * info->func_info_rec_size;
-			t = btf__type_by_id(btf, finfo->type_id);
-			short_name = btf__name_by_offset(btf, t->name_off);
-		} else if (i == 0 && sub_prog_cnt == 1) {
-			/* no subprog */
-			if (info->name[0])
-				short_name = info->name;
-		} else
-			short_name = "F";
-		if (short_name)
-			name_len += snprintf(ksymbol_event->name + name_len,
-					     KSYM_NAME_LEN - name_len,
-					     "_%s", short_name);
 
+		name_len = synthesize_bpf_prog_name(ksymbol_event->name,
+						    KSYM_NAME_LEN, info, btf, i);
 		ksymbol_event->header.size += PERF_ALIGN(name_len + 1,
 							 sizeof(u64));
 
-- 
2.17.1

[PATCH v2 perf,bpf 2/2] perf, bpf: show more BPF program info in print_bpf_prog_info()

[Song Liu]

This patch enables showing bpf program name, address, and size in the
header.

Before the patch:

  perf report --header-only
  ...
  # bpf_prog_info of id 9
  # bpf_prog_info of id 10
  # bpf_prog_info of id 13

After the patch:

  # bpf_prog_info 9: bpf_prog_7be49e3934a125ba addr 0xffffffffa0024947 size 229
  # bpf_prog_info 10: bpf_prog_2a142ef67aaad174 addr 0xffffffffa007c94d size 229
  # bpf_prog_info 13: bpf_prog_47368425825d7384_task__task_newt addr 0xffffffffa0251137 size 369

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/perf/util/bpf-event.c | 40 +++++++++++++++++++++++++++++++++++++
 tools/perf/util/bpf-event.h | 10 +++++++++-
 tools/perf/util/header.c    |  5 +++--
 3 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index b615933c6a8c..6951712dd19b 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -438,3 +438,43 @@ int bpf_event__add_sb_event(struct perf_evlist **evlist,
 
 	return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env);
 }
+
+void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
+				    struct perf_env *env,
+				    FILE *fp)
+{
+	__u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
+	__u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
+	char name[KSYM_NAME_LEN];
+	struct btf *btf = NULL;
+	u32 sub_prog_cnt, i;
+
+	sub_prog_cnt = info->nr_jited_ksyms;
+	if (sub_prog_cnt != info->nr_prog_tags ||
+	    sub_prog_cnt != info->nr_jited_func_lens)
+		return;
+
+	if (info->btf_id) {
+		struct btf_node *node;
+
+		node = perf_env__find_btf(env, info->btf_id);
+		if (node)
+			btf = btf__new((__u8 *)(node->data),
+				       node->data_size);
+	}
+
+	if (sub_prog_cnt == 1) {
+		synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0);
+		fprintf(fp, "# bpf_prog_info %u: %s addr 0x%llx size %u\n",
+			info->id, name, prog_addrs[0], prog_lens[0]);
+		return;
+	}
+
+	fprintf(fp, "# bpf_prog_info %u:\n", info->id);
+	for (i = 0; i < sub_prog_cnt; i++) {
+		synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i);
+
+		fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n",
+			i, name, prog_addrs[i], prog_lens[i]);
+	}
+}
diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
index 8cb1189149ec..d9cb4170ae79 100644
--- a/tools/perf/util/bpf-event.h
+++ b/tools/perf/util/bpf-event.h
@@ -38,7 +38,9 @@ int perf_event__synthesize_bpf_events(struct perf_session *session,
 				      struct record_opts *opts);
 int bpf_event__add_sb_event(struct perf_evlist **evlist,
 				 struct perf_env *env);
-
+void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
+				    struct perf_env *env,
+				    FILE *fp);
 #else
 static inline int machine__process_bpf_event(struct machine *machine __maybe_unused,
 					     union perf_event *event __maybe_unused,
@@ -61,5 +63,11 @@ static inline int bpf_event__add_sb_event(struct perf_evlist **evlist __maybe_un
 	return 0;
 }
 
+void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
+				    struct perf_env *env,
+				    FILE *fp)
+{
+
+}
 #endif // HAVE_LIBBPF_SUPPORT
 #endif
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 01dda2f65d36..b9e693825873 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1468,8 +1468,9 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
 
 		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
 		next = rb_next(&node->rb_node);
-		fprintf(fp, "# bpf_prog_info of id %u\n",
-			node->info_linear->info.id);
+
+		bpf_event__print_bpf_prog_info(&node->info_linear->info,
+					       env, fp);
 	}
 
 	up_read(&env->bpf_progs.lock);
-- 
2.17.1

Re: [PATCH v2 perf,bpf 2/2] perf, bpf: show more BPF program info in print_bpf_prog_info()

[Arnaldo Carvalho de Melo]

Em Tue, Mar 19, 2019 at 09:54:54AM -0700, Song Liu escreveu:
> This patch enables showing bpf program name, address, and size in the
> header.
> 
> Before the patch:
> 
>   perf report --header-only
>   ...
>   # bpf_prog_info of id 9
>   # bpf_prog_info of id 10
>   # bpf_prog_info of id 13
> 
> After the patch:
> 
>   # bpf_prog_info 9: bpf_prog_7be49e3934a125ba addr 0xffffffffa0024947 size 229
>   # bpf_prog_info 10: bpf_prog_2a142ef67aaad174 addr 0xffffffffa007c94d size 229
>   # bpf_prog_info 13: bpf_prog_47368425825d7384_task__task_newt addr 0xffffffffa0251137 size 369
> index 8cb1189149ec..d9cb4170ae79 100644
> --- a/tools/perf/util/bpf-event.h
> +++ b/tools/perf/util/bpf-event.h
> @@ -38,7 +38,9 @@ int perf_event__synthesize_bpf_events(struct perf_session *session,
>  				      struct record_opts *opts);
>  int bpf_event__add_sb_event(struct perf_evlist **evlist,
>  				 struct perf_env *env);
> -
> +void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
> +				    struct perf_env *env,
> +				    FILE *fp);
>  #else
>  static inline int machine__process_bpf_event(struct machine *machine __maybe_unused,
>  					     union perf_event *event __maybe_unused,
> @@ -61,5 +63,11 @@ static inline int bpf_event__add_sb_event(struct perf_evlist **evlist __maybe_un
>  	return 0;
>  }
>  
> +void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,

Missing static inline here, as well as the __maybe_unused, I'm fixing it

> +				    struct perf_env *env,
> +				    FILE *fp)
> +{
> +
> +}
>  #endif // HAVE_LIBBPF_SUPPORT
>  #endif
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index 01dda2f65d36..b9e693825873 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -1468,8 +1468,9 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
>  
>  		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
>  		next = rb_next(&node->rb_node);
> -		fprintf(fp, "# bpf_prog_info of id %u\n",
> -			node->info_linear->info.id);
> +
> +		bpf_event__print_bpf_prog_info(&node->info_linear->info,
> +					       env, fp);
>  	}
>  
>  	up_read(&env->bpf_progs.lock);
> -- 
> 2.17.1

-- 

- Arnaldo