On Thu, Feb 7, 2019 at 8:15 AM Mauricio Vasquez <mauricio.vasquez@...> wrote:
Hello folks,
We have an eBPF program that shares a 64-bits integer with userspace using an array map. The eBPF program only reads the integer while the user-space application only writes it.
We know this is possible that under some conditions, for example the integer is not aligned to cache line size in x86_64, the reader can see a partially updated value. We wonder if eBPF have some guarantees about
not just cache line, you mean not in its naturally aligned boundary? One load/store is actually broken into multiple loads/stores by the compiler?
atomicity of the load operation in this case, or if this is totally dependent on the target architecture.
Is there a way to implement this without using bpf_spin_lock?
So you mean both user space and bpf program are using bpf_spin_lock?
