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Mercier" , , , , , , , , , , , In-Reply-To: <20260921002206.184660-3-tjmercier@google.com> References: <20260921002206.184660-1-tjmercier@google.com> <20260921002206.184660-3-tjmercier@google.com> X-Mailer: mkdraft (claude review draft; edit before sending) Content-Transfer-Encoding: 8bit Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Sun, Sep 20, 2026 at 05:22 PM T.J. Mercier wrote: > + l = __lookup_elem_raw(htab, head, hash, key, key_size, &n); > + if (l) { > + /* > + * Pairs with smp_wmb() in alloc_htab_elem() to ensure > + * value/pptr reads happen after key/hash match on > + * recycled elements. > + */ > + smp_rmb(); > + return l; > + } Is this AI suggestion to add barriers? I think it should be on the program side. If users really care then they will add such barriers. Doing it unconditionally will cost performance for everyone. Especially on arm64. If you disagree, please provide ./bench bpf-hashmap-lookup numbers on arm64 to demonstrate that perf is the same. pw-bot: cr