[v2,perf,bpf,07/11] perf, bpf: save btf in a rbtree in perf_env
diff mbox series

Message ID 20190215000010.2590505-6-songliubraving@fb.com
State Changes Requested
Delegated to: BPF Maintainers
Headers show
Series
  • perf annotation of BPF programs
Related show

Commit Message

Song Liu Feb. 15, 2019, midnight UTC
btf contains information necessary to annotate bpf programs. This patch
saves btf for bpf programs loaded in the system.

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/perf/util/bpf-event.c | 22 +++++++++++++
 tools/perf/util/bpf-event.h |  7 ++++
 tools/perf/util/env.c       | 65 +++++++++++++++++++++++++++++++++++++
 tools/perf/util/env.h       |  3 ++
 4 files changed, 97 insertions(+)

Comments

Arnaldo Carvalho de Melo Feb. 15, 2019, 2:30 p.m. UTC | #1
Em Thu, Feb 14, 2019 at 04:00:08PM -0800, Song Liu escreveu:
> btf contains information necessary to annotate bpf programs. This patch
> saves btf for bpf programs loaded in the system.
> 
> Signed-off-by: Song Liu <songliubraving@fb.com>
> ---
>  tools/perf/util/bpf-event.c | 22 +++++++++++++
>  tools/perf/util/bpf-event.h |  7 ++++
>  tools/perf/util/env.c       | 65 +++++++++++++++++++++++++++++++++++++
>  tools/perf/util/env.h       |  3 ++
>  4 files changed, 97 insertions(+)
> 
> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
> index ead599bc4f4e..37a5b8134e00 100644
> --- a/tools/perf/util/bpf-event.c
> +++ b/tools/perf/util/bpf-event.c
> @@ -30,6 +30,27 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused,
>  	return 0;
>  }
>  
> +static int perf_fetch_btf(struct perf_env *env, u32 btf_id, struct btf *btf)

Please use perf_env__fetch_bpf

> +{
> +	struct btf_node *node;
> +	u32 data_size;
> +	const void *data;
> +
> +	data = btf__get_raw_data(btf, &data_size);
> +
> +	node = malloc(data_size + sizeof(struct btf_node));
> +
> +	if (!node)
> +		return -1;
> +
> +	node->id = btf_id;
> +	node->data_size = data_size;
> +	memcpy(node->data, data, data_size);
> +
> +	perf_env__insert_btf(env, node);

Just like you did above :-)

> +	return 0;
> +}
> +
>  /*
>   * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
>   * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
> @@ -109,6 +130,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
>  			goto out;
>  		}
>  		has_btf = true;
> +		perf_fetch_btf(env, info->btf_id, btf);
>  	}
>  
>  	/* Synthesize PERF_RECORD_KSYMBOL */
> diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
> index 11e6730b6105..60ce24e4e5c6 100644
> --- a/tools/perf/util/bpf-event.h
> +++ b/tools/perf/util/bpf-event.h
> @@ -20,6 +20,13 @@ struct bpf_prog_info_node {
>  	struct rb_node			rb_node;
>  };
>  
> +struct btf_node {
> +	struct rb_node	rb_node;
> +	u32		id;
> +	u32		data_size;
> +	char		data[];
> +};
> +
>  #ifdef HAVE_LIBBPF_SUPPORT
>  int machine__process_bpf_event(struct machine *machine, union perf_event *event,
>  			       struct perf_sample *sample);
> diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
> index 665b6fe3c7b2..6f9e3d4b94bc 100644
> --- a/tools/perf/util/env.c
> +++ b/tools/perf/util/env.c
> @@ -61,6 +61,57 @@ struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
>  	return node;
>  }
>  
> +void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
> +{
> +	struct rb_node *parent = NULL;
> +	__u32 btf_id = btf_node->id;
> +	struct btf_node *node;
> +	struct rb_node **p;
> +
> +	down_write(&env->bpf_info_lock);
> +	p = &env->btfs.rb_node;
> +
> +	while (*p != NULL) {
> +		parent = *p;
> +		node = rb_entry(parent, struct btf_node, rb_node);
> +		if (btf_id < node->id) {
> +			p = &(*p)->rb_left;
> +		} else if (btf_id > node->id) {
> +			p = &(*p)->rb_right;
> +		} else {
> +			pr_debug("duplicated btf %u\n", btf_id);

			goto out:

> +			up_write(&env->bpf_info_lock);
> +			return;
> +		}
> +	}
> +
> +	rb_link_node(&btf_node->rb_node, parent, p);
> +	rb_insert_color(&btf_node->rb_node, &env->btfs);
out:
> +	up_write(&env->bpf_info_lock);
> +}
> +
> +struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
> +{
> +	struct btf_node *node = NULL;
> +	struct rb_node *n;
> +
> +	down_read(&env->bpf_info_lock);
> +	n = env->btfs.rb_node;
> +
> +	while (n) {
> +		node = rb_entry(n, struct btf_node, rb_node);
> +		if (btf_id < node->id)
> +			n = n->rb_left;
> +		else if (btf_id > node->id)
> +			n = n->rb_right;
> +		else
> +			break;
> +	}
> +
> +	up_read(&env->bpf_info_lock);
> +	return node;
> +}
> +
>  /* purge data in bpf_prog_infos tree */
>  static void purge_bpf_info(struct perf_env *env)

The above should've been perf_env__purge_bpf()

>  {
> @@ -80,6 +131,19 @@ static void purge_bpf_info(struct perf_env *env)
>  		rb_erase_init(&node->rb_node, root);
>  		free(node);
>  	}
> +
> +	root = &env->btfs;
> +	next = rb_first(root);
> +
> +	while (next) {
> +		struct btf_node *node;
> +
> +		node = rb_entry(next, struct btf_node, rb_node);
> +		next = rb_next(&node->rb_node);
> +		rb_erase_init(&node->rb_node, root);
> +		free(node);
> +	}
> +
>  	up_write(&env->bpf_info_lock);
>  }
>  
> @@ -117,6 +181,7 @@ void perf_env__exit(struct perf_env *env)
>  static void init_bpf_rb_trees(struct perf_env *env)
>  {
>  	env->bpf_prog_infos = RB_ROOT;
> +	env->btfs = RB_ROOT;
>  	init_rwsem(&env->bpf_info_lock);
>  }
>  
> diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
> index a6d25e91bc98..f0c74255423c 100644
> --- a/tools/perf/util/env.h
> +++ b/tools/perf/util/env.h
> @@ -74,6 +74,7 @@ struct perf_env {
>  	 */
>  	struct rw_semaphore	bpf_info_lock;
>  	struct rb_root		bpf_prog_infos;
> +	struct rb_root		btfs;
>  };
>  
>  extern struct perf_env perf_env;
> @@ -94,4 +95,6 @@ void perf_env__insert_bpf_prog_info(struct perf_env *env,
>  				    struct bpf_prog_info_node *info_node);
>  struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
>  							__u32 prog_id);
> +void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node);
> +struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id);
>  #endif /* __PERF_ENV_H */
> -- 
> 2.17.1

Patch
diff mbox series

diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index ead599bc4f4e..37a5b8134e00 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -30,6 +30,27 @@  int machine__process_bpf_event(struct machine *machine __maybe_unused,
 	return 0;
 }
 
+static int perf_fetch_btf(struct perf_env *env, u32 btf_id, struct btf *btf)
+{
+	struct btf_node *node;
+	u32 data_size;
+	const void *data;
+
+	data = btf__get_raw_data(btf, &data_size);
+
+	node = malloc(data_size + sizeof(struct btf_node));
+
+	if (!node)
+		return -1;
+
+	node->id = btf_id;
+	node->data_size = data_size;
+	memcpy(node->data, data, data_size);
+
+	perf_env__insert_btf(env, node);
+	return 0;
+}
+
 /*
  * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
  * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
@@ -109,6 +130,7 @@  static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 			goto out;
 		}
 		has_btf = true;
+		perf_fetch_btf(env, info->btf_id, btf);
 	}
 
 	/* Synthesize PERF_RECORD_KSYMBOL */
diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
index 11e6730b6105..60ce24e4e5c6 100644
--- a/tools/perf/util/bpf-event.h
+++ b/tools/perf/util/bpf-event.h
@@ -20,6 +20,13 @@  struct bpf_prog_info_node {
 	struct rb_node			rb_node;
 };
 
+struct btf_node {
+	struct rb_node	rb_node;
+	u32		id;
+	u32		data_size;
+	char		data[];
+};
+
 #ifdef HAVE_LIBBPF_SUPPORT
 int machine__process_bpf_event(struct machine *machine, union perf_event *event,
 			       struct perf_sample *sample);
diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 665b6fe3c7b2..6f9e3d4b94bc 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -61,6 +61,57 @@  struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
 	return node;
 }
 
+void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
+{
+	struct rb_node *parent = NULL;
+	__u32 btf_id = btf_node->id;
+	struct btf_node *node;
+	struct rb_node **p;
+
+	down_write(&env->bpf_info_lock);
+	p = &env->btfs.rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		node = rb_entry(parent, struct btf_node, rb_node);
+		if (btf_id < node->id) {
+			p = &(*p)->rb_left;
+		} else if (btf_id > node->id) {
+			p = &(*p)->rb_right;
+		} else {
+			pr_debug("duplicated btf %u\n", btf_id);
+			up_write(&env->bpf_info_lock);
+			return;
+		}
+	}
+
+	rb_link_node(&btf_node->rb_node, parent, p);
+	rb_insert_color(&btf_node->rb_node, &env->btfs);
+	up_write(&env->bpf_info_lock);
+}
+
+struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
+{
+	struct btf_node *node = NULL;
+	struct rb_node *n;
+
+	down_read(&env->bpf_info_lock);
+	n = env->btfs.rb_node;
+
+	while (n) {
+		node = rb_entry(n, struct btf_node, rb_node);
+		if (btf_id < node->id)
+			n = n->rb_left;
+		else if (btf_id > node->id)
+			n = n->rb_right;
+		else
+			break;
+	}
+
+	up_read(&env->bpf_info_lock);
+	return node;
+}
+
 /* purge data in bpf_prog_infos tree */
 static void purge_bpf_info(struct perf_env *env)
 {
@@ -80,6 +131,19 @@  static void purge_bpf_info(struct perf_env *env)
 		rb_erase_init(&node->rb_node, root);
 		free(node);
 	}
+
+	root = &env->btfs;
+	next = rb_first(root);
+
+	while (next) {
+		struct btf_node *node;
+
+		node = rb_entry(next, struct btf_node, rb_node);
+		next = rb_next(&node->rb_node);
+		rb_erase_init(&node->rb_node, root);
+		free(node);
+	}
+
 	up_write(&env->bpf_info_lock);
 }
 
@@ -117,6 +181,7 @@  void perf_env__exit(struct perf_env *env)
 static void init_bpf_rb_trees(struct perf_env *env)
 {
 	env->bpf_prog_infos = RB_ROOT;
+	env->btfs = RB_ROOT;
 	init_rwsem(&env->bpf_info_lock);
 }
 
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index a6d25e91bc98..f0c74255423c 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -74,6 +74,7 @@  struct perf_env {
 	 */
 	struct rw_semaphore	bpf_info_lock;
 	struct rb_root		bpf_prog_infos;
+	struct rb_root		btfs;
 };
 
 extern struct perf_env perf_env;
@@ -94,4 +95,6 @@  void perf_env__insert_bpf_prog_info(struct perf_env *env,
 				    struct bpf_prog_info_node *info_node);
 struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
 							__u32 prog_id);
+void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node);
+struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id);
 #endif /* __PERF_ENV_H */