From: Stephen Hemminger <stephen@networkplumber.org>
To: Marat Khalili <qm2k21@gmail.com>
Cc: Konstantin Ananyev <konstantin.ananyev@huawei.com>, dev@dpdk.org
Subject: Re: [PATCH 8/9] bpf: use relaxed stores for callback inuse tracking
Date: Sun, 11 Oct 2026 12:52:56 -0700 [thread overview]
Message-ID: <20261011125256.753e35bd@phoenix.local> (raw)
In-Reply-To: <20261011182158.124246-9-qm2k21@gmail.com>
On Sun, 11 Oct 2026 18:21:56 +0000
Marat Khalili <qm2k21@gmail.com> wrote:
> Direct assignment to an atomic variable defaults to sequentially
> consistent memory order in C11. Since cross-thread memory ordering
> for packet callback execution and unload is already explicitly
> enforced by memory barriers, sequentially consistent stores are
> unnecessary and may emit redundant barrier instructions on weakly
> ordered architectures.
>
> Update bpf_eth_cbi_inuse() and bpf_eth_cbi_unuse() to use
> rte_atomic_store_explicit() with rte_memory_order_relaxed, matching
> the relaxed loads already used in bpf_eth_cbi_wait().
>
> Signed-off-by: Marat Khalili <qm2k21@gmail.com>
> ---
Already covered by smb_mb conversion patch.
If you want, can just make that into one patch which does
the conversion to bool and gets rid of smp_mb.
next prev parent reply other threads:[~2026-10-11 19:53 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-11 18:21 [PATCH 0/9] bpf: clean up and document ethdev callback synchronization Marat Khalili
2026-10-11 18:21 ` [PATCH 1/9] bpf: document packet callback unload sequence Marat Khalili
2026-10-11 18:21 ` [PATCH 2/9] bpf: document ethdev callback threading limitations Marat Khalili
2026-10-11 18:21 ` [PATCH 3/9] bpf: reject Tx callback installation with MT_LOCKFREE Marat Khalili
2026-10-11 18:21 ` [PATCH 4/9] bpf: add callback flag to skip multi-thread check Marat Khalili
2026-10-11 19:48 ` Stephen Hemminger
2026-10-11 20:12 ` Marat Khalili
2026-10-11 18:21 ` [PATCH 5/9] bpf: remove redundant memory barrier on unload Marat Khalili
2026-10-11 19:50 ` Stephen Hemminger
2026-10-11 20:14 ` Marat Khalili
2026-10-11 18:21 ` [PATCH 6/9] bpf: simplify callback inuse tracking to boolean flag Marat Khalili
2026-10-11 19:51 ` Stephen Hemminger
2026-10-11 20:17 ` Marat Khalili
2026-10-11 18:21 ` [PATCH 7/9] bpf: reformat packet callback unload diagram Marat Khalili
2026-10-11 18:21 ` [PATCH 8/9] bpf: use relaxed stores for callback inuse tracking Marat Khalili
2026-10-11 19:52 ` Stephen Hemminger [this message]
2026-10-11 20:24 ` Marat Khalili
2026-10-11 18:21 ` [PATCH 9/9] bpf: make callback handle atomic with relaxed access Marat Khalili
2026-10-11 19:54 ` Stephen Hemminger
2026-10-11 20:31 ` Marat Khalili
2026-10-11 20:29 ` [RFC] bpf: fix callback unload with concurrent Tx burst Stephen Hemminger
2026-10-12 21:09 ` [PATCH v2 0/9] bpf: clean up and document ethdev callback synchronization Marat Khalili
2026-10-12 21:09 ` [PATCH v2 1/9] bpf: document packet callback unload sequence Marat Khalili
2026-10-12 21:09 ` [PATCH v2 2/9] bpf: document ethdev callback threading limitations Marat Khalili
2026-10-12 21:44 ` Stephen Hemminger
2026-10-12 21:09 ` [PATCH v2 3/9] bpf: reject Tx callback installation with MT_LOCKFREE Marat Khalili
2026-10-12 21:09 ` [PATCH v2 4/9] bpf: remove redundant memory barrier on unload Marat Khalili
2026-10-12 21:09 ` [PATCH v2 5/9] bpf: simplify callback inuse tracking to boolean flag Marat Khalili
2026-10-12 21:09 ` [PATCH v2 6/9] bpf: reformat packet callback unload diagram Marat Khalili
2026-10-12 21:09 ` [PATCH v2 7/9] bpf: use relaxed accesses for callback inuse tracking Marat Khalili
2026-10-12 21:09 ` [PATCH v2 8/9] bpf: make callback handle atomic with relaxed access Marat Khalili
2026-10-12 21:09 ` [PATCH v2 9/9] bpf: add callback flag to skip multi-thread check Marat Khalili
2026-10-13 16:55 ` Stephen Hemminger
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