linux/tools/bpf
Andrii Nakryiko 31332ccb75 bpftool: Stop emitting static variables in BPF skeleton
As discussed in [0], stop emitting static variables in BPF skeletons to avoid
issues with name-conflicting static variables across multiple
statically-linked BPF object files.

Users using static variables to pass data between BPF programs and user-space
should do a trivial one-time switch according to the following simple rules:
  - read-only `static volatile const` variables should be converted to
    `volatile const`;
  - read/write `static volatile` variables should just drop `static volatile`
    modifiers to become global variables/symbols. To better handle older Clang
    versions, such newly converted global variables should be explicitly
    initialized with a specific value or `= 0`/`= {}`, whichever is
    appropriate.

  [0] https://lore.kernel.org/bpf/CAEf4BzZo7_r-hsNvJt3w3kyrmmBJj7ghGY8+k4nvKF0KLjma=w@mail.gmail.com/T/#m664d4b0d6b31ac8b2669360e0fc2d6962e9f5ec1

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210507054119.270888-5-andrii@kernel.org
2021-05-11 15:07:17 -07:00
..
bpftool bpftool: Stop emitting static variables in BPF skeleton 2021-05-11 15:07:17 -07:00
resolve_btfids tools/resolve_btfids: Fix warnings 2021-03-31 12:09:12 -07:00
runqslower tools/runqslower: Allow substituting custom vmlinux.h for the build 2021-03-02 20:14:02 -08:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
bpf_asm.c docs: networking: convert filter.txt to ReST 2020-04-28 14:39:46 -07:00
bpf_dbg.c bpf: Simplify the calculation of variables 2021-03-04 19:24:53 -08:00
bpf_exp.l bpf: fix cbpf parser bug for octal numbers 2018-06-03 07:46:55 -07:00
bpf_exp.y tools, bpf_asm: Exit non-zero on errors 2021-02-26 22:53:50 +01:00
bpf_jit_disasm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 232 2019-06-19 17:09:06 +02:00
Makefile tools/bpf: build: Make sure resolve_btfids cleans up after itself 2020-09-01 18:04:15 +02:00