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 B33FA191F94; Wed, 4 Mar 2026 13:19:05 +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=1772630345; cv=none; b=qDl0BAKEX6X27mN7ncRkK6AS+OSdHRNVLOZ6uBY1N+bdC1/bWW/aI533oASsIBMFW3aMecYuEvy13znK2j0pQjx8rian3pNokCDZQkrOcDwLqQLySonTdk3/3N3ANdqLXseLTY9K2dYIDhdPFLwVgyYRD1GacnADtMC+EeiT4cM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772630345; c=relaxed/simple; bh=C1LUb2aaVVJMppU4WEn1TilKT8PcWh18uvF7AdKGFTk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=VVyTkihZLxb1vIKx8JSkYQYFjRGIs5kViKGVIvFeme4vo3rIHuSx4IzQaS+YXWmMW/spQG18kDNje0JHnLX3D0McL6Ku+dU3LNi9VxEQEbqn2xMbdt3FMJ1G5TRT2Kaew6ebBR/qvK0t04RBDhUuQoAqJDowwQ+zMXcgOJ/F/Ag= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ms+4BAi1; 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="ms+4BAi1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E170C19423; Wed, 4 Mar 2026 13:19:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772630345; bh=C1LUb2aaVVJMppU4WEn1TilKT8PcWh18uvF7AdKGFTk=; h=From:To:Cc:Subject:Date:From; b=ms+4BAi1nnyGyti6BVz6jeLLcq1MRKH2eE4fOgRLcEcYzp3QJzkThz/G7kCHgI2XZ Krxo70RgsPhY3ck5qvxIJQ0Vl+8zALgsj1URsVZoqsMaXTG1/f0nz8XPA9eeql2qtO C+ioX4AlXq36IGdbg/BpTzMuqmCnz5BYiJKZvguPzyLU5Wi2Bd5/I8tZBobeEFCYNo rLq2kWHCIpRic9x0dsiCMvNrbmyRhscYoIQngsRyJLT2/dd1JPT1t6ZVHA8cBOK3bf oKFgPu8RmGtfgAWQ5VZ0BqDNYQO9rUD7Q+OeT9v3uihhbNRXXoG0vqQMyzfCI0ydTl NrBEUXsv9qjQg== From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= To: Michael Chan , Pavan Chebbi , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Willem de Bruijn Subject: [PATCH net-next v2 0/3] ethtool: Dynamic RSS context indirection table resizing Date: Wed, 4 Mar 2026 14:18:50 +0100 Message-ID: <20260304131855.3225539-1-bjorn@kernel.org> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi! Some NICs (e.g. bnxt) change their RSS indirection table size based on the queue count, because the hardware table is a shared resource. The ethtool core locks ctx->indir_size at context creation, so drivers have to reject channel changes when RSS contexts exist. This series adds resize helpers and wires them up in bnxt. Patch 1 adds core helpers: ethtool_rxfh_can_resize() - read-only validation ethtool_rxfh_resize() - fold/unfold a raw table in place ethtool_rxfh_ctxs_can_resize() - validate all non-default contexts ethtool_rxfh_ctxs_resize() - resize all non-default contexts, with locking and RSS_NTF notifications Patch 2 uses them in bnxt_set_channels(). Validation runs before bnxt_close_nic(); actual resize is deferred until after. RSS table size only changes on P5 chips with older firmware. Patch 3 adds HW tests in rss_drv.py (devices without dynamic table sizing are skipped): resize_periodic - fold/unfold with a non-default [3,2,1,0]xN pattern, verifying exact content preservation (main + ctx) resize_nonperiodic_reject - non-periodic table blocks channel reduction, with an extra periodic context to exercise multi-context validation (main + ctx) resize_nonperiodic_no_corruption - failed resize leaves table contents and channel count unchanged (main + ctx) Running the tests: # On real hardware sudo NETIF=eth0 ./rss_drv.py Changes v1 -> v2: - Dropped netdevsim support and netdevsim selftest (Jakub) - Split ethtool_rxfh_contexts_resize_all() into separate validate (ethtool_rxfh_ctxs_can_resize) and apply (ethtool_rxfh_ctxs_resize) so drivers can validate before closing the device (Jakub) - Shortened helper names (Jakub) - Replaced scoped_guard(mutex) with explicit mutex_lock/unlock (Jakub) - Removed defensive zero-size check, bare expressions instead of != 0 comparisons, ! instead of == 0 (Jakub) - In bnxt, moved bnxt_check_rings() before RSS validation and deferred actual resize to after bnxt_close_nic() (Jakub, Michael) - Added comment that RSS table size only changes on P5 chips with older firmware (Michael) - Use non-default [3,2,1,0]xN pattern set via netlink to distinguish correct fold from driver resetting to defaults (Jakub) - Check exact indirection table pattern, not just set(indir) (Jakub) - Use ksft_raises() instead of try/except/else (Jakub) - Removed queue_count=8 from NetDrvEnv (Jakub) - Added ksft_variants to resize_nonperiodic_reject for ctx coverage - Added extra periodic context in reject test for multi-context validation coverage - Added resize_nonperiodic_no_corruption test Open items: - No user-controlled minimum table size yet. The plan is to record the user-provided indirection table length in the context (e.g. ctx->user_indir_size) and use it as a floor when folding: reject if new_size < user_indir_size. This way the user's original table size serves as an implicit minimum, preventing the driver from shrinking below what the user intended. Left for a follow-up. Björn Töpel (3): ethtool: Add RSS indirection table resize helpers bnxt_en: Resize RSS contexts on channel count change selftests: rss_drv: Add RSS indirection table resize tests .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 36 +++- include/linux/ethtool.h | 4 + net/ethtool/common.c | 146 ++++++++++++++++ .../selftests/drivers/net/hw/rss_drv.py | 163 +++++++++++++++++- 4 files changed, 338 insertions(+), 11 deletions(-) base-commit: ed0abfe93fd135dac223e87a3c945017b1fa8bfc -- 2.53.0