kernel.git/tools/bpf/bpftool/link.c, branch linux-5.19.y

bpf, x86: Generate trampolines from bpf_tramp_links

2022-05-11T00:50:40Z

Replace struct bpf_tramp_progs with struct bpf_tramp_links to collect struct bpf_tramp_link(s) for a trampoline. struct bpf_tramp_link extends bpf_link to act as a linked list node. arch_prepare_bpf_trampoline() accepts a struct bpf_tramp_links to collects all bpf_tramp_link(s) that a trampoline should call. Change BPF trampoline and bpf_struct_ops to pass bpf_tramp_links instead of bpf_tramp_progs. Signed-off-by: Kui-Feng Lee Signed-off-by: Alexei Starovoitov Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220510205923.3206889-2-kuifeng@fb.com

bpftool: Add missing link types

2022-04-04T21:54:34Z

Will display the link type names in bpftool link show output Signed-off-by: Milan Landaverde Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220331154555.422506-3-milan@mdaverde.com

bpftool: Fix error check when calling hashmap__new()

2022-01-13T01:01:36Z

hashmap__new() encodes errors with ERR_PTR(), hence it's not valid to check the returned pointer against NULL and IS_ERR() has to be used instead. libbpf_get_error() can't be used in this case as hashmap__new() is not part of the public libbpf API and it'll continue using ERR_PTR() after libbpf 1.0. Fixes: 8f184732b60b ("bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects") Fixes: 2828d0d75b73 ("bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing") Fixes: d6699f8e0f83 ("bpftool: Switch to libbpf's hashmap for PIDs/names references") Signed-off-by: Mauricio Vásquez Signed-off-by: Andrii Nakryiko Reviewed-by: Quentin Monnet Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20220107152620.192327-2-mauricio@kinvolk.io

bpftool: Switch to libbpf's hashmap for PIDs/names references

2021-10-26T00:31:39Z

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211023205154.6710-6-quentin@isovalent.com

bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects

2021-10-26T00:31:38Z

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 Signed-off-by: Andrii Nakryiko 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.c

2021-10-26T00:31:38Z

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211023205154.6710-3-quentin@isovalent.com

tools: bpftool: Update and synchronise option list in doc and help msg

2021-07-30T22:40:27Z

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 Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210730215435.7095-5-quentin@isovalent.com

bpftool: Implement link_query for bpf iterators

2020-08-21T21:01:39Z

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 Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200821184420.574430-1-yhs@fb.com

tools/bpftool: Fix compilation warnings in 32-bit mode

2020-08-13T23:45:41Z

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 Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200813204945.1020225-2-andriin@fb.com

tools/bpftool: Add `link detach` subcommand

2020-08-02T03:38:29Z

Add ability to force-detach BPF link. Also add missing error message, if specified link ID is wrong. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20200731182830.286260-5-andriin@fb.com