To coordinate across multiple encoders at collection time, there will be
a need to access the set of encoders. Rework the unused
btf_encoders__*() API to facilitate this.
Committer notes:
Removed btf_encoders__for_each_encoder() duplicate define, pointed out
by Jiri Olsa.
Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Andrii Nakryiko <andrii@xxxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Eduard Zingerman <eddyz87@xxxxxxxxx>
Cc: Hao Luo <haoluo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: John Fastabend <john.fastabend@xxxxxxxxx>
Cc: KP Singh <kpsingh@xxxxxxxxxxxx>
Cc: Kui-Feng Lee <sinquersw@xxxxxxxxx>
Cc: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Stanislav Fomichev <sdf@xxxxxxxxxx>
Cc: Timo Beckers <timo@xxxxxxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Cc: bpf@xxxxxxxxxxxxxxx
---
btf_encoder.c | 36 ++++++++++++++++++++++++++++--------
btf_encoder.h | 6 ------
2 files changed, 28 insertions(+), 14 deletions(-)
diff --git a/btf_encoder.c b/btf_encoder.c
index 71f67ae..74ab61b 100644
--- a/btf_encoder.c
+++ b/btf_encoder.c
@@ -30,6 +30,7 @@
#include <errno.h>
#include <stdint.h>
+#include <pthread.h>
struct elf_function {
const char *name;
@@ -79,19 +80,36 @@ struct btf_encoder {
} functions;
};
-void btf_encoders__add(struct list_head *encoders, struct btf_encoder *encoder)
-{
- list_add_tail(&encoder->node, encoders);
-}
+static LIST_HEAD(encoders);
+static pthread_mutex_t encoders__lock = PTHREAD_MUTEX_INITIALIZER;
+
+/* mutex only needed for add/delete, as this can happen in multiple encoding
+ * threads. Traversal of the list is currently confined to thread collection.
+ */
-struct btf_encoder *btf_encoders__first(struct list_head *encoders)
+#define btf_encoders__for_each_encoder(encoder) \
+ list_for_each_entry(encoder, &encoders, node)
+
+static void btf_encoders__add(struct btf_encoder *encoder)
{
- return list_first_entry(encoders, struct btf_encoder, node);
+ pthread_mutex_lock(&encoders__lock);
+ list_add_tail(&encoder->node, &encoders);
+ pthread_mutex_unlock(&encoders__lock);
}
-struct btf_encoder *btf_encoders__next(struct btf_encoder *encoder)
+static void btf_encoders__delete(struct btf_encoder *encoder)
{
- return list_next_entry(encoder, node);
+ struct btf_encoder *existing = NULL;
+
+ pthread_mutex_lock(&encoders__lock);
+ /* encoder may not have been added to list yet; check. */
+ btf_encoders__for_each_encoder(existing) {
+ if (encoder == existing)
+ break;
+ }
+ if (encoder == existing)
+ list_del(&encoder->node);
+ pthread_mutex_unlock(&encoders__lock);
}
#define PERCPU_SECTION ".data..percpu"
@@ -1505,6 +1523,7 @@ struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filenam
if (encoder->verbose)
printf("File %s:\n", cu->filename);
+ btf_encoders__add(encoder);
}
out:
return encoder;
@@ -1519,6 +1538,7 @@ void btf_encoder__delete(struct btf_encoder *encoder)
if (encoder == NULL)
return;
+ btf_encoders__delete(encoder);
__gobuffer__delete(&encoder->percpu_secinfo);
zfree(&encoder->filename);
btf__free(encoder->btf);
diff --git a/btf_encoder.h b/btf_encoder.h
index a65120c..34516bb 100644
--- a/btf_encoder.h
+++ b/btf_encoder.h
@@ -23,12 +23,6 @@ int btf_encoder__encode(struct btf_encoder *encoder);
int btf_encoder__encode_cu(struct btf_encoder *encoder, struct cu *cu, struct conf_load *conf_load);
-void btf_encoders__add(struct list_head *encoders, struct btf_encoder *encoder);
-
-struct btf_encoder *btf_encoders__first(struct list_head *encoders);
-
-struct btf_encoder *btf_encoders__next(struct btf_encoder *encoder);
-
struct btf *btf_encoder__btf(struct btf_encoder *encoder);
int btf_encoder__add_encoder(struct btf_encoder *encoder, struct btf_encoder *other);
--
2.31.1
