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| author | Alexei Starovoitov <ast@kernel.org> | 2023-12-09 21:37:33 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-12-09 21:37:33 -0800 |
| commit | 5bcbdf72df88a351642627d94b93af7c9301b6e2 (patch) | |
| tree | 21a2ba3658473f297c164c78c15ef1ce6eedec20 /kernel | |
| parent | 5181dc08f79583c6dead80208137a97e68ff07b0 (diff) | |
| parent | 88f6047191e69bdd02cf1b9b5b514f7e514e8b86 (diff) | |
Merge branch 'add-new-bpf_cpumask_weight-kfunc'
David Vernet says:
====================
Add new bpf_cpumask_weight() kfunc
It can be useful to query how many bits are set in a cpumask. For
example, if you want to perform special logic for the last remaining
core that's set in a mask. This logic is already exposed through the
main kernel's cpumask header as cpumask_weight(), so it would be useful
to add a new bpf_cpumask_weight() kfunc which wraps it and does the
same.
This patch series was built and tested on top of commit 2146f7fe6e02
("Merge branch 'allocate-bpf-trampoline-on-bpf_prog_pack'").
====================
Link: https://lore.kernel.org/r/20231207210843.168466-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/cpumask.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/kernel/bpf/cpumask.c b/kernel/bpf/cpumask.c index e01c741e54e7..7499b7d8c06f 100644 --- a/kernel/bpf/cpumask.c +++ b/kernel/bpf/cpumask.c @@ -405,6 +405,17 @@ __bpf_kfunc u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1, return cpumask_any_and_distribute(src1, src2); } +/** + * bpf_cpumask_weight() - Return the number of bits in @cpumask. + * @cpumask: The cpumask being queried. + * + * Count the number of set bits in the given cpumask. + */ +__bpf_kfunc u32 bpf_cpumask_weight(const struct cpumask *cpumask) +{ + return cpumask_weight(cpumask); +} + __bpf_kfunc_end_defs(); BTF_SET8_START(cpumask_kfunc_btf_ids) @@ -432,6 +443,7 @@ BTF_ID_FLAGS(func, bpf_cpumask_full, KF_RCU) BTF_ID_FLAGS(func, bpf_cpumask_copy, KF_RCU) BTF_ID_FLAGS(func, bpf_cpumask_any_distribute, KF_RCU) BTF_ID_FLAGS(func, bpf_cpumask_any_and_distribute, KF_RCU) +BTF_ID_FLAGS(func, bpf_cpumask_weight, KF_RCU) BTF_SET8_END(cpumask_kfunc_btf_ids) static const struct btf_kfunc_id_set cpumask_kfunc_set = { |