* [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall
@ 2022-09-24 10:13 Wang Yufen
2022-09-24 10:13 ` [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load) Wang Yufen
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Wang Yufen @ 2022-09-24 10:13 UTC (permalink / raw)
To: quentin, ast, daniel, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
Add auto_attach optional to support one-step load-attach-pin_link.
For example,
$ bpftool prog loadall test.o /sys/fs/bpf/test autoattach
$ bpftool link
26: tracing name test1 tag f0da7d0058c00236 gpl
loaded_at 2022-09-09T21:39:49+0800 uid 0
xlated 88B jited 55B memlock 4096B map_ids 3
btf_id 55
28: kprobe name test3 tag 002ef1bef0723833 gpl
loaded_at 2022-09-09T21:39:49+0800 uid 0
xlated 88B jited 56B memlock 4096B map_ids 3
btf_id 55
57: tracepoint name oncpu tag 7aa55dfbdcb78941 gpl
loaded_at 2022-09-09T21:41:32+0800 uid 0
xlated 456B jited 265B memlock 4096B map_ids 17,13,14,15
btf_id 82
$ bpftool link
1: tracing prog 26
prog_type tracing attach_type trace_fentry
3: perf_event prog 28
10: perf_event prog 57
The autoattach optional can support tracepoints, k(ret)probes,
u(ret)probes.
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
---
v5 -> v6: skip the programs not supporting auto-attach,
and change optional name from "auto_attach" to "autoattach"
v4 -> v5: some formatting nits of doc
v3 -> v4: rename functions, update doc, bash and do_help()
v2 -> v3: switch to extend prog load command instead of extend perf
v2: https://patchwork.kernel.org/project/netdevbpf/patch/20220824033837.458197-1-weiyongjun1@huawei.com/
v1: https://patchwork.kernel.org/project/netdevbpf/patch/20220816151725.153343-1-weiyongjun1@huawei.com/
tools/bpf/bpftool/prog.c | 76 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 74 insertions(+), 2 deletions(-)
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index c81362a001ba..b1cbd06dee19 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -1453,6 +1453,67 @@ get_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
return ret;
}
+static int
+auto_attach_program(struct bpf_program *prog, const char *path)
+{
+ struct bpf_link *link;
+ int err;
+
+ link = bpf_program__attach(prog);
+ if (!link)
+ return -1;
+
+ err = bpf_link__pin(link, path);
+ if (err) {
+ bpf_link__destroy(link);
+ return err;
+ }
+ return 0;
+}
+
+static int pathname_concat(const char *path, const char *name, char *buf)
+{
+ int len;
+
+ len = snprintf(buf, PATH_MAX, "%s/%s", path, name);
+ if (len < 0)
+ return -EINVAL;
+ if (len >= PATH_MAX)
+ return -ENAMETOOLONG;
+
+ return 0;
+}
+
+static int
+auto_attach_programs(struct bpf_object *obj, const char *path)
+{
+ struct bpf_program *prog;
+ char buf[PATH_MAX];
+ int err;
+
+ bpf_object__for_each_program(prog, obj) {
+ err = pathname_concat(path, bpf_program__name(prog), buf);
+ if (err)
+ goto err_unpin_programs;
+
+ err = auto_attach_program(prog, buf);
+ if (err && errno != EOPNOTSUPP)
+ goto err_unpin_programs;
+ }
+
+ return 0;
+
+err_unpin_programs:
+ while ((prog = bpf_object__prev_program(obj, prog))) {
+ if (pathname_concat(path, bpf_program__name(prog), buf))
+ continue;
+
+ bpf_program__unpin(prog, buf);
+ }
+
+ return err;
+}
+
static int load_with_options(int argc, char **argv, bool first_prog_only)
{
enum bpf_prog_type common_prog_type = BPF_PROG_TYPE_UNSPEC;
@@ -1464,6 +1525,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
struct bpf_program *prog = NULL, *pos;
unsigned int old_map_fds = 0;
const char *pinmaps = NULL;
+ bool auto_attach = false;
struct bpf_object *obj;
struct bpf_map *map;
const char *pinfile;
@@ -1583,6 +1645,9 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
goto err_free_reuse_maps;
pinmaps = GET_ARG();
+ } else if (is_prefix(*argv, "autoattach")) {
+ auto_attach = true;
+ NEXT_ARG();
} else {
p_err("expected no more arguments, 'type', 'map' or 'dev', got: '%s'?",
*argv);
@@ -1692,14 +1757,20 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
goto err_close_obj;
}
- err = bpf_obj_pin(bpf_program__fd(prog), pinfile);
+ if (auto_attach)
+ err = auto_attach_program(prog, pinfile);
+ else
+ err = bpf_obj_pin(bpf_program__fd(prog), pinfile);
if (err) {
p_err("failed to pin program %s",
bpf_program__section_name(prog));
goto err_close_obj;
}
} else {
- err = bpf_object__pin_programs(obj, pinfile);
+ if (auto_attach)
+ err = auto_attach_programs(obj, pinfile);
+ else
+ err = bpf_object__pin_programs(obj, pinfile);
if (err) {
p_err("failed to pin all programs");
goto err_close_obj;
@@ -2338,6 +2409,7 @@ static int do_help(int argc, char **argv)
" [type TYPE] [dev NAME] \\\n"
" [map { idx IDX | name NAME } MAP]\\\n"
" [pinmaps MAP_DIR]\n"
+ " [autoattach]\n"
" %1$s %2$s attach PROG ATTACH_TYPE [MAP]\n"
" %1$s %2$s detach PROG ATTACH_TYPE [MAP]\n"
" %1$s %2$s run PROG \\\n"
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load)
2022-09-24 10:13 [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Wang Yufen
@ 2022-09-24 10:13 ` Wang Yufen
2022-09-26 16:20 ` Daniel Borkmann
2022-09-24 10:13 ` [bpf-next v6 3/3] bpftool: Update the bash completion(add " Wang Yufen
2022-09-26 10:46 ` [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Quentin Monnet
2 siblings, 1 reply; 7+ messages in thread
From: Wang Yufen @ 2022-09-24 10:13 UTC (permalink / raw)
To: quentin, ast, daniel, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
Add autoattach optional to prog load|loadall for supporting
one-step load-attach-pin_link.
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
---
tools/bpf/bpftool/Documentation/bpftool-prog.rst | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
index eb1b2a254eb1..2d9f27a0120f 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
@@ -31,7 +31,7 @@ PROG COMMANDS
| **bpftool** **prog dump xlated** *PROG* [{**file** *FILE* | **opcodes** | **visual** | **linum**}]
| **bpftool** **prog dump jited** *PROG* [{**file** *FILE* | **opcodes** | **linum**}]
| **bpftool** **prog pin** *PROG* *FILE*
-| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*]
+| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog tracelog**
@@ -131,7 +131,7 @@ DESCRIPTION
contain a dot character ('.'), which is reserved for future
extensions of *bpffs*.
- **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*]
+ **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
Load bpf program(s) from binary *OBJ* and pin as *PATH*.
**bpftool prog load** pins only the first program from the
*OBJ* as *PATH*. **bpftool prog loadall** pins all programs
@@ -150,6 +150,15 @@ DESCRIPTION
Optional **pinmaps** argument can be provided to pin all
maps under *MAP_DIR* directory.
+ If **autoattach** is specified program will be attached
+ before pin. In that case, only the link (representing the
+ program attached to its hook) is pinned, not the program as
+ such, so the path won't show in "**bpftool prog show -f**",
+ only show in "**bpftool link show -f**". Also, this only works
+ when bpftool (libbpf) is able to infer all necessary information
+ from the objectfile, in particular, it's not supported for all
+ program types.
+
Note: *PATH* must be located in *bpffs* mount. It must not
contain a dot character ('.'), which is reserved for future
extensions of *bpffs*.
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [bpf-next v6 3/3] bpftool: Update the bash completion(add autoattach to prog load)
2022-09-24 10:13 [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Wang Yufen
2022-09-24 10:13 ` [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load) Wang Yufen
@ 2022-09-24 10:13 ` Wang Yufen
2022-09-26 10:46 ` [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Quentin Monnet
2 siblings, 0 replies; 7+ messages in thread
From: Wang Yufen @ 2022-09-24 10:13 UTC (permalink / raw)
To: quentin, ast, daniel, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
Add autoattach optional to prog load|loadall for supporting
one-step load-attach-pin_link.
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
---
tools/bpf/bpftool/bash-completion/bpftool | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index dc1641e3670e..2957b42cab67 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -505,6 +505,7 @@ _bpftool()
_bpftool_once_attr 'type'
_bpftool_once_attr 'dev'
_bpftool_once_attr 'pinmaps'
+ _bpftool_once_attr 'autoattach'
return 0
;;
esac
--
2.25.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall
2022-09-24 10:13 [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Wang Yufen
2022-09-24 10:13 ` [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load) Wang Yufen
2022-09-24 10:13 ` [bpf-next v6 3/3] bpftool: Update the bash completion(add " Wang Yufen
@ 2022-09-26 10:46 ` Quentin Monnet
2022-09-27 11:04 ` wangyufen
2 siblings, 1 reply; 7+ messages in thread
From: Quentin Monnet @ 2022-09-26 10:46 UTC (permalink / raw)
To: Wang Yufen, ast, daniel, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
Sat Sep 24 2022 11:13:48 GMT+0100 (British Summer Time) ~ Wang Yufen
<wangyufen@huawei.com>
> Add auto_attach optional to support one-step load-attach-pin_link.
>
> For example,
> $ bpftool prog loadall test.o /sys/fs/bpf/test autoattach
>
> $ bpftool link
> 26: tracing name test1 tag f0da7d0058c00236 gpl
> loaded_at 2022-09-09T21:39:49+0800 uid 0
> xlated 88B jited 55B memlock 4096B map_ids 3
> btf_id 55
> 28: kprobe name test3 tag 002ef1bef0723833 gpl
> loaded_at 2022-09-09T21:39:49+0800 uid 0
> xlated 88B jited 56B memlock 4096B map_ids 3
> btf_id 55
> 57: tracepoint name oncpu tag 7aa55dfbdcb78941 gpl
> loaded_at 2022-09-09T21:41:32+0800 uid 0
> xlated 456B jited 265B memlock 4096B map_ids 17,13,14,15
> btf_id 82
>
> $ bpftool link
> 1: tracing prog 26
> prog_type tracing attach_type trace_fentry
> 3: perf_event prog 28
> 10: perf_event prog 57
>
> The autoattach optional can support tracepoints, k(ret)probes,
> u(ret)probes.
>
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
> Signed-off-by: Wang Yufen <wangyufen@huawei.com>
> ---
> v5 -> v6: skip the programs not supporting auto-attach,
> and change optional name from "auto_attach" to "autoattach"
> v4 -> v5: some formatting nits of doc
> v3 -> v4: rename functions, update doc, bash and do_help()
> v2 -> v3: switch to extend prog load command instead of extend perf
> v2: https://patchwork.kernel.org/project/netdevbpf/patch/20220824033837.458197-1-weiyongjun1@huawei.com/
> v1: https://patchwork.kernel.org/project/netdevbpf/patch/20220816151725.153343-1-weiyongjun1@huawei.com/
> tools/bpf/bpftool/prog.c | 76 ++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 74 insertions(+), 2 deletions(-)
>
> diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
> index c81362a001ba..b1cbd06dee19 100644
> --- a/tools/bpf/bpftool/prog.c
> +++ b/tools/bpf/bpftool/prog.c
> @@ -1453,6 +1453,67 @@ get_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
> return ret;
> }
>
> +static int
> +auto_attach_program(struct bpf_program *prog, const char *path)
> +{
> + struct bpf_link *link;
> + int err;
> +
> + link = bpf_program__attach(prog);
> + if (!link)
> + return -1;
> +
> + err = bpf_link__pin(link, path);
> + if (err) {
> + bpf_link__destroy(link);
> + return err;
> + }
> + return 0;
> +}
> +
> +static int pathname_concat(const char *path, const char *name, char *buf)
> +{
> + int len;
> +
> + len = snprintf(buf, PATH_MAX, "%s/%s", path, name);
> + if (len < 0)
> + return -EINVAL;
> + if (len >= PATH_MAX)
> + return -ENAMETOOLONG;
> +
> + return 0;
> +}
> +
> +static int
> +auto_attach_programs(struct bpf_object *obj, const char *path)
> +{
> + struct bpf_program *prog;
> + char buf[PATH_MAX];
> + int err;
> +
> + bpf_object__for_each_program(prog, obj) {
> + err = pathname_concat(path, bpf_program__name(prog), buf);
> + if (err)
> + goto err_unpin_programs;
> +
> + err = auto_attach_program(prog, buf);
> + if (err && errno != EOPNOTSUPP)
> + goto err_unpin_programs;
If I read the above correctly, we skip entirely programs that couldn't
be auto-attached. I'm not sure what Andrii had in mind exactly, but it
would make sense to me to fallback to regular program pinning if the
program couldn't be attached/linked, so we still keep it loaded in the
kernel after bpftool exits. Probably with a p_info() message to let
users know?
> + }
> +
> + return 0;
> +
> +err_unpin_programs:
> + while ((prog = bpf_object__prev_program(obj, prog))) {
> + if (pathname_concat(path, bpf_program__name(prog), buf))
> + continue;
> +
> + bpf_program__unpin(prog, buf);
> + }
> +
> + return err;
> +}
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load)
2022-09-24 10:13 ` [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load) Wang Yufen
@ 2022-09-26 16:20 ` Daniel Borkmann
2022-09-27 11:05 ` wangyufen
0 siblings, 1 reply; 7+ messages in thread
From: Daniel Borkmann @ 2022-09-26 16:20 UTC (permalink / raw)
To: Wang Yufen, quentin, ast, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
On 9/24/22 12:13 PM, Wang Yufen wrote:
> Add autoattach optional to prog load|loadall for supporting
> one-step load-attach-pin_link.
>
> Signed-off-by: Wang Yufen <wangyufen@huawei.com>
> ---
> tools/bpf/bpftool/Documentation/bpftool-prog.rst | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> index eb1b2a254eb1..2d9f27a0120f 100644
> --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
> @@ -31,7 +31,7 @@ PROG COMMANDS
> | **bpftool** **prog dump xlated** *PROG* [{**file** *FILE* | **opcodes** | **visual** | **linum**}]
> | **bpftool** **prog dump jited** *PROG* [{**file** *FILE* | **opcodes** | **linum**}]
> | **bpftool** **prog pin** *PROG* *FILE*
> -| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*]
> +| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
> | **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
> | **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
> | **bpftool** **prog tracelog**
> @@ -131,7 +131,7 @@ DESCRIPTION
> contain a dot character ('.'), which is reserved for future
> extensions of *bpffs*.
>
> - **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*]
> + **bpftool prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
> Load bpf program(s) from binary *OBJ* and pin as *PATH*.
> **bpftool prog load** pins only the first program from the
> *OBJ* as *PATH*. **bpftool prog loadall** pins all programs
> @@ -150,6 +150,15 @@ DESCRIPTION
> Optional **pinmaps** argument can be provided to pin all
> maps under *MAP_DIR* directory.
>
> + If **autoattach** is specified program will be attached
> + before pin. In that case, only the link (representing the
> + program attached to its hook) is pinned, not the program as
> + such, so the path won't show in "**bpftool prog show -f**",
> + only show in "**bpftool link show -f**". Also, this only works
> + when bpftool (libbpf) is able to infer all necessary information
> + from the objectfile, in particular, it's not supported for all
> + program types.
Related to Quentin's comment, the documentation should also describe clear semantics
on what happens in failure case. I presume the use case you have in mind is to use
this facility for scripts e.g. to run/load some tests objs? Thus would be good to describe
to users what they need to do/clean up when things only partially succeed etc..
> Note: *PATH* must be located in *bpffs* mount. It must not
> contain a dot character ('.'), which is reserved for future
> extensions of *bpffs*.
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall
2022-09-26 10:46 ` [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Quentin Monnet
@ 2022-09-27 11:04 ` wangyufen
0 siblings, 0 replies; 7+ messages in thread
From: wangyufen @ 2022-09-27 11:04 UTC (permalink / raw)
To: Quentin Monnet, ast, daniel, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
在 2022/9/26 18:46, Quentin Monnet 写道:
> Sat Sep 24 2022 11:13:48 GMT+0100 (British Summer Time) ~ Wang Yufen
> <wangyufen@huawei.com>
>> Add auto_attach optional to support one-step load-attach-pin_link.
>>
>> For example,
>> $ bpftool prog loadall test.o /sys/fs/bpf/test autoattach
>>
>> $ bpftool link
>> 26: tracing name test1 tag f0da7d0058c00236 gpl
>> loaded_at 2022-09-09T21:39:49+0800 uid 0
>> xlated 88B jited 55B memlock 4096B map_ids 3
>> btf_id 55
>> 28: kprobe name test3 tag 002ef1bef0723833 gpl
>> loaded_at 2022-09-09T21:39:49+0800 uid 0
>> xlated 88B jited 56B memlock 4096B map_ids 3
>> btf_id 55
>> 57: tracepoint name oncpu tag 7aa55dfbdcb78941 gpl
>> loaded_at 2022-09-09T21:41:32+0800 uid 0
>> xlated 456B jited 265B memlock 4096B map_ids 17,13,14,15
>> btf_id 82
>>
>> $ bpftool link
>> 1: tracing prog 26
>> prog_type tracing attach_type trace_fentry
>> 3: perf_event prog 28
>> 10: perf_event prog 57
>>
>> The autoattach optional can support tracepoints, k(ret)probes,
>> u(ret)probes.
>>
>> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
>> Signed-off-by: Wang Yufen <wangyufen@huawei.com>
>> ---
>> v5 -> v6: skip the programs not supporting auto-attach,
>> and change optional name from "auto_attach" to "autoattach"
>> v4 -> v5: some formatting nits of doc
>> v3 -> v4: rename functions, update doc, bash and do_help()
>> v2 -> v3: switch to extend prog load command instead of extend perf
>> v2: https://patchwork.kernel.org/project/netdevbpf/patch/20220824033837.458197-1-weiyongjun1@huawei.com/
>> v1: https://patchwork.kernel.org/project/netdevbpf/patch/20220816151725.153343-1-weiyongjun1@huawei.com/
>> tools/bpf/bpftool/prog.c | 76 ++++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 74 insertions(+), 2 deletions(-)
>>
>> diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
>> index c81362a001ba..b1cbd06dee19 100644
>> --- a/tools/bpf/bpftool/prog.c
>> +++ b/tools/bpf/bpftool/prog.c
>> @@ -1453,6 +1453,67 @@ get_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
>> return ret;
>> }
>>
>> +static int
>> +auto_attach_program(struct bpf_program *prog, const char *path)
>> +{
>> + struct bpf_link *link;
>> + int err;
>> +
>> + link = bpf_program__attach(prog);
>> + if (!link)
>> + return -1;
>> +
>> + err = bpf_link__pin(link, path);
>> + if (err) {
>> + bpf_link__destroy(link);
>> + return err;
>> + }
>> + return 0;
>> +}
>> +
>> +static int pathname_concat(const char *path, const char *name, char *buf)
>> +{
>> + int len;
>> +
>> + len = snprintf(buf, PATH_MAX, "%s/%s", path, name);
>> + if (len < 0)
>> + return -EINVAL;
>> + if (len >= PATH_MAX)
>> + return -ENAMETOOLONG;
>> +
>> + return 0;
>> +}
>> +
>> +static int
>> +auto_attach_programs(struct bpf_object *obj, const char *path)
>> +{
>> + struct bpf_program *prog;
>> + char buf[PATH_MAX];
>> + int err;
>> +
>> + bpf_object__for_each_program(prog, obj) {
>> + err = pathname_concat(path, bpf_program__name(prog), buf);
>> + if (err)
>> + goto err_unpin_programs;
>> +
>> + err = auto_attach_program(prog, buf);
>> + if (err && errno != EOPNOTSUPP)
>> + goto err_unpin_programs;
> If I read the above correctly, we skip entirely programs that couldn't
> be auto-attached. I'm not sure what Andrii had in mind exactly, but it
> would make sense to me to fallback to regular program pinning if the
> program couldn't be attached/linked, so we still keep it loaded in the
> kernel after bpftool exits. Probably with a p_info() message to let
> users know?
Thanks for your comment.
I agree with you.
add in v7.
>
>> + }
>> +
>> + return 0;
>> +
>> +err_unpin_programs:
>> + while ((prog = bpf_object__prev_program(obj, prog))) {
>> + if (pathname_concat(path, bpf_program__name(prog), buf))
>> + continue;
>> +
>> + bpf_program__unpin(prog, buf);
>> + }
>> +
>> + return err;
>> +}
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load)
2022-09-26 16:20 ` Daniel Borkmann
@ 2022-09-27 11:05 ` wangyufen
0 siblings, 0 replies; 7+ messages in thread
From: wangyufen @ 2022-09-27 11:05 UTC (permalink / raw)
To: Daniel Borkmann, quentin, ast, andrii, martin.lau, song, yhs,
john.fastabend, kpsingh, sdf, haoluo, jolsa, davem, kuba, hawk,
nathan, ndesaulniers, trix
Cc: bpf, linux-kernel, netdev, llvm
在 2022/9/27 0:20, Daniel Borkmann 写道:
> On 9/24/22 12:13 PM, Wang Yufen wrote:
>> Add autoattach optional to prog load|loadall for supporting
>> one-step load-attach-pin_link.
>>
>> Signed-off-by: Wang Yufen <wangyufen@huawei.com>
>> ---
>> tools/bpf/bpftool/Documentation/bpftool-prog.rst | 13 +++++++++++--
>> 1 file changed, 11 insertions(+), 2 deletions(-)
>>
>> diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
>> b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
>> index eb1b2a254eb1..2d9f27a0120f 100644
>> --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
>> +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
>> @@ -31,7 +31,7 @@ PROG COMMANDS
>> | **bpftool** **prog dump xlated** *PROG* [{**file** *FILE* |
>> **opcodes** | **visual** | **linum**}]
>> | **bpftool** **prog dump jited** *PROG* [{**file** *FILE* |
>> **opcodes** | **linum**}]
>> | **bpftool** **prog pin** *PROG* *FILE*
>> -| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH*
>> [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*]
>> [**dev** *NAME*] [**pinmaps** *MAP_DIR*]
>> +| **bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH*
>> [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*]
>> [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
>> | **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
>> | **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
>> | **bpftool** **prog tracelog**
>> @@ -131,7 +131,7 @@ DESCRIPTION
>> contain a dot character ('.'), which is reserved for future
>> extensions of *bpffs*.
>> - **bpftool prog { load | loadall }** *OBJ* *PATH* [**type**
>> *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev**
>> *NAME*] [**pinmaps** *MAP_DIR*]
>> + **bpftool prog { load | loadall }** *OBJ* *PATH* [**type**
>> *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev**
>> *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
>> Load bpf program(s) from binary *OBJ* and pin as *PATH*.
>> **bpftool prog load** pins only the first program from the
>> *OBJ* as *PATH*. **bpftool prog loadall** pins all programs
>> @@ -150,6 +150,15 @@ DESCRIPTION
>> Optional **pinmaps** argument can be provided to pin all
>> maps under *MAP_DIR* directory.
>> + If **autoattach** is specified program will be attached
>> + before pin. In that case, only the link (representing the
>> + program attached to its hook) is pinned, not the program as
>> + such, so the path won't show in "**bpftool prog show -f**",
>> + only show in "**bpftool link show -f**". Also, this only
>> works
>> + when bpftool (libbpf) is able to infer all necessary
>> information
>> + from the objectfile, in particular, it's not supported for
>> all
>> + program types.
>
> Related to Quentin's comment, the documentation should also describe
> clear semantics
> on what happens in failure case. I presume the use case you have in
> mind is to use
> this facility for scripts e.g. to run/load some tests objs? Thus would
> be good to describe
> to users what they need to do/clean up when things only partially
> succeed etc..
Thanks for your comment.
add in v7, please check.
>
>> Note: *PATH* must be located in *bpffs* mount. It must not
>> contain a dot character ('.'), which is reserved for future
>> extensions of *bpffs*.
>>
>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2022-09-27 11:05 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-09-24 10:13 [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Wang Yufen
2022-09-24 10:13 ` [bpf-next v6 2/3] bpftool: Update doc (add autoattach to prog load) Wang Yufen
2022-09-26 16:20 ` Daniel Borkmann
2022-09-27 11:05 ` wangyufen
2022-09-24 10:13 ` [bpf-next v6 3/3] bpftool: Update the bash completion(add " Wang Yufen
2022-09-26 10:46 ` [bpf-next v6 1/3] bpftool: Add auto_attach for bpf prog load|loadall Quentin Monnet
2022-09-27 11:04 ` wangyufen
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).