diff options
| author | Dave Marchevsky <davemarchevsky@fb.com> | 2023-10-31 14:56:25 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-11-01 22:33:53 -0700 |
| commit | 15fb6f2b6c4c3c129adc2412ae12ec15e60a6adb (patch) | |
| tree | 03f6aca296ff77a4608cbb68663a7415b72f29b1 /kernel | |
| parent | 391145ba2accc48b596f3d438af1a6255b62a555 (diff) | |
bpf: Add __bpf_hook_{start,end} macros
Not all uses of __diag_ignore_all(...) in BPF-related code in order to
suppress warnings are wrapping kfunc definitions. Some "hook point"
definitions - small functions meant to be used as attach points for
fentry and similar BPF progs - need to suppress -Wmissing-declarations.
We could use __bpf_kfunc_{start,end}_defs added in the previous patch in
such cases, but this might be confusing to someone unfamiliar with BPF
internals. Instead, this patch adds __bpf_hook_{start,end} macros,
currently having the same effect as __bpf_kfunc_{start,end}_defs, then
uses them to suppress warnings for two hook points in the kernel itself
and some bpf_testmod hook points as well.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231031215625.2343848-2-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup/rstat.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index d80d7a608141..c0adb7254b45 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -156,19 +156,16 @@ static struct cgroup *cgroup_rstat_cpu_pop_updated(struct cgroup *pos, * optimize away the callsite. Therefore, __weak is needed to ensure that the * call is still emitted, by telling the compiler that we don't know what the * function might eventually be. - * - * __diag_* below are needed to dismiss the missing prototype warning. */ -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "kfuncs which will be used in BPF programs"); + +__bpf_hook_start(); __weak noinline void bpf_rstat_flush(struct cgroup *cgrp, struct cgroup *parent, int cpu) { } -__diag_pop(); +__bpf_hook_end(); /* see cgroup_rstat_flush() */ static void cgroup_rstat_flush_locked(struct cgroup *cgrp) |