From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CA4F92E36E7 for ; Fri, 4 Jul 2025 17:05:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751648752; cv=none; b=uwXrmYAw8k+CXKqRBj9tumJUd486lRnQSyne1UtFtSYZyHZEXRb969IJYrS5iwfyH+LiNgP8MGPbdgZ0w7D30wBdHffBtc4TotnhdpExXtxCnSXTlETeLE09dhBtDkFvKxrCF2iw16ZGYZ3Z61kRXa0GV5VPtzkCNjZapgiPw7c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751648752; c=relaxed/simple; bh=X0tykLQZ7gVKoARvYw2ieqVcpK9qSxB+3MuwK7cUNrI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oIL8YFhkO2cwu8WdmFVHxDZDMh5TGGL5aDa1ucrRX1hDZdvqGsg0lXeKvKHGNXIHd9jKhruKdhnBvN9RfJQArjov4cl/YeetxPtaMSIpsSvDIIfYvNCw/uCAYhQ/sDRyLOdH4UBTkr5Qy9ZCR3v72ri0KfshX2xXf36pHIl6Rvg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qqo9WsEn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qqo9WsEn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A40AAC4CEE3; Fri, 4 Jul 2025 17:05:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1751648752; bh=X0tykLQZ7gVKoARvYw2ieqVcpK9qSxB+3MuwK7cUNrI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qqo9WsEnDvtIUCntLBfxrjoo4dKwMojINKmWyP7igIaBdTgKGNha7pfA/5WKyRKcs kv9r4GUFBcmmrGEB1GQklhX8RoeVXA3/YkPldpiAEjFIfGDFWAipTrb1QN7duZY/QC eLS+hZwxTNvnP/lMsfx5yHnij48P1/i6yJuGD+hbi9f0llCvbAmWgHzLbkr+7Y5fwR IM3BC7iTHC05TIoWJmrI3+POkZW88zrbxHUVegNROdfJXJj4uROVPPeaHkitL+yH8r hHd/Fs+h61OjKwvRw/Bfd120GaQ+JWfos4mMwuh6DqazDqSq9Wgx/Q6tT68yjZvRG/ Vl2M0CJrwzehQ== Date: Fri, 4 Jul 2025 18:05:48 +0100 From: Simon Horman To: Mingming Cao Cc: netdev@vger.kernel.org, bjking1@linux.ibm.com, haren@linux.ibm.com, ricklind@linux.ibm.com, davemarq@linux.ibm.com Subject: Re: [PATCH v2 net-next 4/4] ibmvnic: Make max subcrq indirect entries tunable via module param Message-ID: <20250704170548.GM41770@horms.kernel.org> References: <20250702171804.86422-1-mmc@linux.ibm.com> <20250702171804.86422-5-mmc@linux.ibm.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250702171804.86422-5-mmc@linux.ibm.com> On Wed, Jul 02, 2025 at 10:18:04AM -0700, Mingming Cao wrote: > This patch increases the default number of subcrq indirect entries from 16 > to 128, a value supported on POWER9 and later systems. Increasing this limit > improves batching efficiency in hypervisor communication, enhancing throughput > under high-load conditions. > > To maintain compatibility with older or constrained systems (e.g., some POWER8 platforms), > a module parameter max_subcrq_indirect is introduced as a transitional mechanism. > This allows administrators to manually reduce the limit if needed. > > The module parameter is not intended for dynamic runtime tuning, but rather > provides forward compatibility without requiring broader structural changes at this time. > > Signed-off-by: Mingming Cao > Reviewed by: Rick Lindsley > Reviewed by: Dave Marquardt > Reviewed by: Brian King > Reviewed by: Haren Myneni Hi, In his review of v1 of this patchset, Jakub said: Module parameters are strongly discouraged. Please provide more details about what this parameter does, I supposed it should be mapped to on of the ethtool -g options. https://lore.kernel.org/netdev/20250701183107.6f6411c1@kernel.org/ Perhaps I'm missing something, but I don't see this discussed or addressed. -- pw-bot: changes-requested