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* bpftool: Switch to libbpf's hashmap for PIDs/names referencesQuentin Monnet2021-10-261-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | In order to show PIDs and names for processes holding references to BPF programs, maps, links, or BTF objects, bpftool creates hash maps to store all relevant information. This commit is part of a set that transitions from the kernel's hash map implementation to the one coming with libbpf. The motivation is to make bpftool less dependent of kernel headers, to ease the path to a potential out-of-tree mirror, like libbpf has. This is the third and final step of the transition, in which we convert the hash maps used for storing the information about the processes holding references to BPF objects (programs, maps, links, BTF), and at last we drop the inclusion of tools/include/linux/hashtable.h. Note: Checkpatch complains about the use of __weak declarations, and the missing empty lines after the bunch of empty function declarations when compiling without the BPF skeletons (none of these were introduced in this patch). We want to keep things as they are, and the reports should be safe to ignore. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211023205154.6710-6-quentin@isovalent.com
* bpftool: Switch to libbpf's hashmap for pinned paths of BPF objectsQuentin Monnet2021-10-261-16/+20
| | | | | | | | | | | | | | | | | | | | | | | In order to show pinned paths for BPF programs, maps, or links when listing them with the "-f" option, bpftool creates hash maps to store all relevant paths under the bpffs. So far, it would rely on the kernel implementation (from tools/include/linux/hashtable.h). We can make bpftool rely on libbpf's implementation instead. The motivation is to make bpftool less dependent of kernel headers, to ease the path to a potential out-of-tree mirror, like libbpf has. This commit is the first step of the conversion: the hash maps for pinned paths for programs, maps, and links are converted to libbpf's hashmap.{c,h}. Other hash maps used for the PIDs of process holding references to BPF objects are left unchanged for now. On the build side, this requires adding a dependency to a second header internal to libbpf, and making it a dependency for the bootstrap bpftool version as well. The rest of the changes are a rather straightforward conversion. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211023205154.6710-4-quentin@isovalent.com
* bpftool: Do not expose and init hash maps for pinned path in main.cQuentin Monnet2021-10-261-1/+8
| | | | | | | | | | | | | | | | | | | BPF programs, maps, and links, can all be listed with their pinned paths by bpftool, when the "-f" option is provided. To do so, bpftool builds hash maps containing all pinned paths for each kind of objects. These three hash maps are always initialised in main.c, and exposed through main.h. There appear to be no particular reason to do so: we can just as well make them static to the files that need them (prog.c, map.c, and link.c respectively), and initialise them only when we want to show objects and the "-f" switch is provided. This may prevent unnecessary memory allocations if the implementation of the hash maps was to change in the future. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211023205154.6710-3-quentin@isovalent.com
* tools: bpftool: Update and synchronise option list in doc and help msgQuentin Monnet2021-07-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | All bpftool commands support the options for JSON output and debug from libbpf. In addition, some commands support additional options corresponding to specific use cases. The list of options described in the man pages for the different commands are not always accurate. The messages for interactive help are mostly limited to HELP_SPEC_OPTIONS, and are even less representative of the actual set of options supported for the commands. Let's update the lists: - HELP_SPEC_OPTIONS is modified to contain the "default" options (JSON and debug), and to be extensible (no ending curly bracket). - All commands use HELP_SPEC_OPTIONS in their help message, and then complete the list with their specific options. - The lists of options in the man pages are updated. - The formatting of the list for bpftool.rst is adjusted to match formatting for the other man pages. This is for consistency, and also because it will be helpful in a future patch to automatically check that the files are synchronised. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210730215435.7095-5-quentin@isovalent.com
* bpftool: Implement link_query for bpf iteratorsYonghong Song2020-08-211-3/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The link query for bpf iterators is implemented. Besides being shown to the user what bpf iterator the link represents, the target_name is also used to filter out what additional information should be printed out, e.g., whether map_id should be shown or not. The following is an example of bpf_iter link dump, plain output or pretty output. $ bpftool link show 11: iter prog 59 target_name task pids test_progs(1749) 34: iter prog 173 target_name bpf_map_elem map_id 127 pids test_progs_1(1753) $ bpftool -p link show [{ "id": 11, "type": "iter", "prog_id": 59, "target_name": "task", "pids": [{ "pid": 1749, "comm": "test_progs" } ] },{ "id": 34, "type": "iter", "prog_id": 173, "target_name": "bpf_map_elem", "map_id": 127, "pids": [{ "pid": 1753, "comm": "test_progs_1" } ] } ] Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200821184420.574430-1-yhs@fb.com
* tools/bpftool: Fix compilation warnings in 32-bit modeAndrii Nakryiko2020-08-141-2/+2
| | | | | | | | | Fix few compilation warnings in bpftool when compiling in 32-bit mode. Abstract away u64 to pointer conversion into a helper function. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200813204945.1020225-2-andriin@fb.com
* tools/bpftool: Add `link detach` subcommandAndrii Nakryiko2020-08-021-1/+36
| | | | | | | | | | | Add ability to force-detach BPF link. Also add missing error message, if specified link ID is wrong. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200731182830.286260-5-andriin@fb.com
* tools, bpftool: Define prog_type_name array only onceTobias Klauser2020-06-251-2/+2
| | | | | | | | | | | | | | | | | | | | Define prog_type_name in prog.c instead of main.h so it is only defined once. This leads to a slight decrease in the binary size of bpftool. Before: text data bss dec hex filename 401032 11936 1573160 1986128 1e4e50 bpftool After: text data bss dec hex filename 399024 11168 1573160 1983352 1e4378 bpftool Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200624143124.12914-1-tklauser@distanz.ch
* tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDsAndrii Nakryiko2020-06-231-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add bpf_iter-based way to find all the processes that hold open FDs against BPF object (map, prog, link, btf). bpftool always attempts to discover this, but will silently give up if kernel doesn't yet support bpf_iter BPF programs. Process name and PID are emitted for each process (task group). Sample output for each of 4 BPF objects: $ sudo ./bpftool prog show 2694: cgroup_device tag 8c42dee26e8cd4c2 gpl loaded_at 2020-06-16T15:34:32-0700 uid 0 xlated 648B jited 409B memlock 4096B pids systemd(1) 2907: cgroup_skb name egress tag 9ad187367cf2b9e8 gpl loaded_at 2020-06-16T18:06:54-0700 uid 0 xlated 48B jited 59B memlock 4096B map_ids 2436 btf_id 1202 pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool map show 2436: array name test_cgr.bss flags 0x400 key 4B value 8B max_entries 1 memlock 8192B btf_id 1202 pids test_progs(2238417), test_progs(2238445) 2445: array name pid_iter.rodata flags 0x480 key 4B value 4B max_entries 1 memlock 8192B btf_id 1214 frozen pids bpftool(2239612) $ sudo ./bpftool link show 61: cgroup prog 2908 cgroup_id 375301 attach_type egress pids test_progs(2238417), test_progs(2238445) 62: cgroup prog 2908 cgroup_id 375344 attach_type egress pids test_progs(2238417), test_progs(2238445) $ sudo ./bpftool btf show 1202: size 1527B prog_ids 2908,2907 map_ids 2436 pids test_progs(2238417), test_progs(2238445) 1242: size 34684B pids bpftool(2258892) Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200619231703.738941-9-andriin@fb.com
* bpftool: Support link show for netns-attached linksJakub Sitnicki2020-06-021-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make `bpf link show` aware of new link type, that is links attached to netns. When listing netns-attached links, display netns inode number as its identifier and link attach type. Sample session: # readlink /proc/self/ns/net net:[4026532251] # bpftool prog show 357: flow_dissector tag a04f5eef06a7f555 gpl loaded_at 2020-05-30T16:53:51+0200 uid 0 xlated 16B jited 37B memlock 4096B 358: flow_dissector tag a04f5eef06a7f555 gpl loaded_at 2020-05-30T16:53:51+0200 uid 0 xlated 16B jited 37B memlock 4096B # bpftool link show 108: netns prog 357 netns_ino 4026532251 attach_type flow_dissector # bpftool link -jp show [{ "id": 108, "type": "netns", "prog_id": 357, "netns_ino": 4026532251, "attach_type": "flow_dissector" } ] (... after netns is gone ...) # bpftool link show 108: netns prog 357 netns_ino 0 attach_type flow_dissector # bpftool link -jp show [{ "id": 108, "type": "netns", "prog_id": 357, "netns_ino": 0, "attach_type": "flow_dissector" } ] Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-9-jakub@cloudflare.com
* bpftool: Extract helpers for showing link attach typeJakub Sitnicki2020-06-021-22/+22
| | | | | | | | | | | Code for printing link attach_type is duplicated in a couple of places, and likely will be duplicated for future link types as well. Create helpers to prevent duplication. Suggested-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-8-jakub@cloudflare.com
* tools, bpftool: Clean subcommand help messagesQuentin Monnet2020-06-011-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | This is a clean-up for the formatting of the do_help functions for bpftool's subcommands. The following fixes are included: - Do not use argv[-2] for "iter" help message, as the help is shown by default if no "iter" action is selected, resulting in messages looking like "./bpftool bpftool pin...". - Do not print unused HELP_SPEC_PROGRAM in help message for "bpftool link". - Andrii used argument indexing to avoid having multiple occurrences of bin_name and argv[-2] in the fprintf() for the help message, for "bpftool gen" and "bpftool link". Let's reuse this for all other help functions. We can remove up to thirty arguments for the "bpftool map" help message. - Harmonise all functions, e.g. use ending quotes-comma on a separate line. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200523010751.23465-1-quentin@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* tools/bpftool: Add bpf_iter support for bptoolYonghong Song2020-05-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, only one command is supported bpftool iter pin <bpf_prog.o> <path> It will pin the trace/iter bpf program in the object file <bpf_prog.o> to the <path> where <path> should be on a bpffs mount. For example, $ bpftool iter pin ./bpf_iter_ipv6_route.o \ /sys/fs/bpf/my_route User can then do a `cat` to print out the results: $ cat /sys/fs/bpf/my_route fe800000000000000000000000000000 40 00000000000000000000000000000000 ... 00000000000000000000000000000000 00 00000000000000000000000000000000 ... 00000000000000000000000000000001 80 00000000000000000000000000000000 ... fe800000000000008c0162fffebdfd57 80 00000000000000000000000000000000 ... ff000000000000000000000000000000 08 00000000000000000000000000000000 ... 00000000000000000000000000000000 00 00000000000000000000000000000000 ... The implementation for ipv6_route iterator is in one of subsequent patches. This patch also added BPF_LINK_TYPE_ITER to link query. In the future, we may add additional parameters to pin command by parameterizing the bpf iterator. For example, a map_id or pid may be added to let bpf program only traverses a single map or task, similar to kernel seq_file single_open(). We may also add introspection command for targets/iterators by leveraging the bpf_iter itself. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200509175920.2477247-1-yhs@fb.com
* bpftool: Add bpf_link show and pin supportAndrii Nakryiko2020-04-291-0/+333
Add `bpftool link show` and `bpftool link pin` commands. Example plain output for `link show` (with showing pinned paths): [vmuser@archvm bpf]$ sudo ~/local/linux/tools/bpf/bpftool/bpftool -f link 1: tracing prog 12 prog_type tracing attach_type fentry pinned /sys/fs/bpf/my_test_link pinned /sys/fs/bpf/my_test_link2 2: tracing prog 13 prog_type tracing attach_type fentry 3: tracing prog 14 prog_type tracing attach_type fentry 4: tracing prog 15 prog_type tracing attach_type fentry 5: tracing prog 16 prog_type tracing attach_type fentry 6: tracing prog 17 prog_type tracing attach_type fentry 7: raw_tracepoint prog 21 tp 'sys_enter' 8: cgroup prog 25 cgroup_id 584 attach_type egress 9: cgroup prog 25 cgroup_id 599 attach_type egress 10: cgroup prog 25 cgroup_id 614 attach_type egress 11: cgroup prog 25 cgroup_id 629 attach_type egress Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200429001614.1544-9-andriin@fb.com