On 5/23/19 9:19 AM, Yonghong Song wrote:
>
>
> On 5/23/19 3:54 AM, Quentin Monnet wrote:
>> libbpf was recently made aware of the log_level attribute for programs,
>> used to specify the level of information expected to be dumped by the
>> verifier.
>>
>> Create an API function to pass additional attributes when loading a
>> bpf_object, so we can set this log_level value in programs when loading
>> them, and so that so that applications relying on libbpf but not calling
> "so that so that" => "so that"
>> bpf_prog_load_xattr() can also use that feature.
>
> Do not fully understand the above statement. From the code below,
> I did not see how the non-zero log_level can be set for bpf_program
> without bpf_prog_load_xattr(). Maybe I miss something?
Looks like next patch uses it when -d is specified.
Probably commit message can be made more clear.
>
>>
>> v2:
>> - We are in a new cycle, bump libbpf extraversion number.
>>
>> Signed-off-by: Quentin Monnet <quentin.monnet@xxxxxxxxxxxxx>
>> Reviewed-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
>> ---
>> tools/lib/bpf/Makefile | 2 +-
>> tools/lib/bpf/libbpf.c | 20 +++++++++++++++++---
>> tools/lib/bpf/libbpf.h | 6 ++++++
>> tools/lib/bpf/libbpf.map | 5 +++++
>> 4 files changed, 29 insertions(+), 4 deletions(-)
>>
>> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
>> index a2aceadf68db..9312066a1ae3 100644
>> --- a/tools/lib/bpf/Makefile
>> +++ b/tools/lib/bpf/Makefile
>> @@ -3,7 +3,7 @@
>> BPF_VERSION = 0
>> BPF_PATCHLEVEL = 0
>> -BPF_EXTRAVERSION = 3
>> +BPF_EXTRAVERSION = 4
>> MAKEFLAGS += --no-print-directory
>> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
>> index 197b574406b3..1c6fb7a3201e 100644
>> --- a/tools/lib/bpf/libbpf.c
>> +++ b/tools/lib/bpf/libbpf.c
>> @@ -2222,7 +2222,7 @@ static bool
>> bpf_program__is_function_storage(struct bpf_program *prog,
>> }
>> static int
>> -bpf_object__load_progs(struct bpf_object *obj)
>> +bpf_object__load_progs(struct bpf_object *obj, int log_level)
>> {
>> size_t i;
>> int err;
>> @@ -2230,6 +2230,7 @@ bpf_object__load_progs(struct bpf_object *obj)
>> for (i = 0; i < obj->nr_programs; i++) {
>> if (bpf_program__is_function_storage(&obj->programs[i], obj))
>> continue;
>> + obj->programs[i].log_level = log_level;
>> err = bpf_program__load(&obj->programs[i],
>> obj->license,
>> obj->kern_version);
>> @@ -2381,10 +2382,14 @@ int bpf_object__unload(struct bpf_object *obj)
>> return 0;
>> }
>> -int bpf_object__load(struct bpf_object *obj)
>> +int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
>> {
>> + struct bpf_object *obj;
>> int err;
>> + if (!attr)
>> + return -EINVAL;
>> + obj = attr->obj;
>> if (!obj)
>> return -EINVAL;
>> @@ -2397,7 +2402,7 @@ int bpf_object__load(struct bpf_object *obj)
>> CHECK_ERR(bpf_object__create_maps(obj), err, out);
>> CHECK_ERR(bpf_object__relocate(obj), err, out);
>> - CHECK_ERR(bpf_object__load_progs(obj), err, out);
>> + CHECK_ERR(bpf_object__load_progs(obj, attr->log_level), err, out);
>> return 0;
>> out:
>> @@ -2406,6 +2411,15 @@ int bpf_object__load(struct bpf_object *obj)
>> return err;
>> }
>> +int bpf_object__load(struct bpf_object *obj)
>> +{
>> + struct bpf_object_load_attr attr = {
>> + .obj = obj,
>> + };
>> +
>> + return bpf_object__load_xattr(&attr);
>> +}
>> +
>> static int check_path(const char *path)
>> {
>> char *cp, errmsg[STRERR_BUFSIZE];
>> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
>> index c5ff00515ce7..e1c748db44f6 100644
>> --- a/tools/lib/bpf/libbpf.h
>> +++ b/tools/lib/bpf/libbpf.h
>> @@ -89,8 +89,14 @@ LIBBPF_API int bpf_object__unpin_programs(struct
>> bpf_object *obj,
>> LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char
>> *path);
>> LIBBPF_API void bpf_object__close(struct bpf_object *object);
>> +struct bpf_object_load_attr {
>> + struct bpf_object *obj;
>> + int log_level;
>> +};
>> +
>> /* Load/unload object into/from kernel */
>> LIBBPF_API int bpf_object__load(struct bpf_object *obj);
>> +LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr
>> *attr);
>> LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
>> LIBBPF_API const char *bpf_object__name(struct bpf_object *obj);
>> LIBBPF_API unsigned int bpf_object__kversion(struct bpf_object *obj);
>> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
>> index 673001787cba..6ce61fa0baf3 100644
>> --- a/tools/lib/bpf/libbpf.map
>> +++ b/tools/lib/bpf/libbpf.map
>> @@ -164,3 +164,8 @@ LIBBPF_0.0.3 {
>> bpf_map_freeze;
>> btf__finalize_data;
>> } LIBBPF_0.0.2;
>> +
>> +LIBBPF_0.0.4 {
>> + global:
>> + bpf_object__load_xattr;
>> +} LIBBPF_0.0.3;
>>
