Messages in this thread | | | Date | Wed, 17 Aug 2022 16:03:28 -0500 | From | David Vernet <> | Subject | Re: [PATCH 3/5] bpf: Add bpf_user_ringbuf_drain() helper |
| |
On Wed, Aug 17, 2022 at 03:24:40PM -0500, David Vernet wrote:
> [...] > > right, I think __atomic_store_n() can be used in libbpf for this with > > seq_cst ordering > > __atomic_store_n(__ATOMIC_SEQ_CST) will do the correct thing on x86, but it > is not guaranteed to provide a full acq/rel barrier according to the C > standard. __atomic_store_n(__ATOMIC_SEQ_CST) means "store-release, and also > participates in the sequentially-consistent global ordering". > > I believe we actually need an __atomic_store_n(__ATOMIC_ACQ_REL) here. I
Sorry, I meant __atomic_exchange_n() rather than __atomic_store_n().
| |