On Wed, Nov 26, 2025 at 6:51 AM Leon Hwang <[email protected]> wrote: > > This patch set introduces the BPF_F_CPU and BPF_F_ALL_CPUS flags for > percpu maps, as the requirement of BPF_F_ALL_CPUS flag for percpu_array > maps was discussed in the thread of > "[PATCH bpf-next v3 0/4] bpf: Introduce global percpu data"[1]. > > The goal of BPF_F_ALL_CPUS flag is to reduce data caching overhead in light > skeletons by allowing a single value to be reused to update values across all > CPUs. This avoids the M:N problem where M cached values are used to update a > map on N CPUs kernel. > > The BPF_F_CPU flag is accompanied by *flags*-embedded cpu info, which > specifies the target CPU for the operation: > > * For lookup operations: the flag field alongside cpu info enable querying > a value on the specified CPU. > * For update operations: the flag field alongside cpu info enable > updating value for specified CPU. > > Links: > [1] https://lore.kernel.org/bpf/[email protected]/ > > Changes: > v11 -> v12: > * Dropped the v11 changes. > * Stabilized the lru_percpu_hash map test by keeping an extra spare entry, > which can be used temporarily during updates to avoid unintended LRU > evictions.
Please rebase and resend. This set got lost during holidays.
