From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794438824; b=kutjxG88/90DNeOWV6SISVlzCVXU7qw+ncC+c8/7d8RzhpwnbWWJ0636B9UQrvYv6R6G tBO1DgWpz2wFIp5cB0OOSA5fRJS0RwBiWd7yYFhywHHpV06VhYFikedEUe3A29XM8CHVn okufdCk31hn/aW8YmEvq0FkQAc6r+/rvdqShimBpzYB/X+nR7Od7dxAaCPth4RukPv8Dn 7ERMMmJ7FtXMcOW3a+ALuePLyu6bUzG+7bHKLEJ7b3srpR0iWeBapmH9pXrrqas2eQVSB vxtVMWoGXjQMOlIE5eFCOfbd6lcZxVND6sVjHsRGGfu7oxgRho46zFVTZ/V8R0vStTw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794438824; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=d0oLmoHltHpv+jhhl+Ta8LiuvtzIB/qkVEpKzt55/5k=; b=z6vhz/1/CQ7Y0d2qcI0WuOcg6mTXXG6fyP75s+uEv8Q7HtxLG+NFE5lhV6fLZzMhfPrh O6KEjmcXvkqwQl0GVoNCw5PA4FRqDuELM0xYE/pXnwx8b/QZTWwuMA+EpfRiQ3oZx87Cy sf1OfycwNq6njrwR9UEiHQc5DrwJJ5Cgh5hXiTmmP0Q71CkLTglFGT6gwrGL+boQZ8Ip8 K/EashFVx+brobc6cWtdLTpQ/aSi9qiHenBNa6L2rEqYpCi6ld+bYNdx2AuTN9CLuiEk6 z7z8t8gwnhcUkoXVNjJ2a+7cdBQfePuRNDl/BdnQxNhPk90YkltCV7hUtIfgOxTgDLw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=aB84wEuj; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 56229606A335 for ; Wed, 11 Nov 2026 23:13:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=aB84wEuj Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A6C31F00A05; Wed, 11 Nov 2026 23:13:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794438824; bh=d0oLmoHltHpv+jhhl+Ta8LiuvtzIB/qkVEpKzt55/5k=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=aB84wEujHHcJ656vv0OahT+Cc6zU12/6wxlfVLnDEbhzR94DXUrWmL1LMBV+Ud2dq W+cg+1T2VsO6Kmy3wBFV0Y7TDp+L+he6DPwUpFOJ8LNJydm3RNWBJie70kb9sT3uFe Y0Ty9ZXmDDXcw4jiKro2XlrNo5ALJoZcXrwUCwG3wpwIZiLads4qaQNLRiz6suAEv3 93dEp2lE/H+XA3kUgIb21uj8a2PzwS/864xNttx/zf8SKdSZI9HpeT+jIWr/uV/kmw k/3AHIQxSqmZlxhHDqeGV25boYD5xfotBzpdMvVQHmSV9qEH6s2XLDcKZ2m0/Ep0Ju Sg7pdMAvV358Q== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH net-next 5/5] net/mlx4: flush pending doorbell when dropping a TX skb Reply-To: sashiko-reviews@lists.linux.dev To: "Joe Damato" Cc: linux-rdma@vger.kernel.org In-Reply-To: <20261110231304.1859217-6-joe@dama.to> References: <20261110231304.1859217-1-joe@dama.to> <20261110231304.1859217-6-joe@dama.to> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 11 Nov 2026 23:13:43 +0000 X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > If mlx4_en_xmit drops an skb (for example because DMA mapping fails) and > that skb happens to be the last one in the batch, the doorbell for the > WQEs posted earlier in the batch isn't written. >=20 > The queue stays awake, though, so those WQEs are eventually announced to > the HW after the next TX, but that depends on traffic and could induce > latency. >=20 > Avoid all of that by writing the pending doorbell in the drop path. >=20 > Signed-off-by: Joe Damato Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110231304.1859= 217-1-joe@dama.to?part=3D5