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 2DDE28BE0 for ; Tue, 28 Mar 2023 15:00:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7DCDC4339B; Tue, 28 Mar 2023 15:00:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680015627; bh=Ch8xmVFoFAeB8JWHwlyotTwrME0To3rFSw8EEP2tmWI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2nOjS4B8IpuL2d2TyNrxA31nhc8cBySUoMUrEDdQLiBDV54WEAbIl8wOEB3mPnxhj /O5VCYkJ3KXCGGdtuMjgSvNTeBSg9CPTmfoIxPhpOnky4B0iECbVGyeTCM9PrspdMA iaa3UxuUaejsDXKftDg91r50otDytgWWSFQMKjOI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Joshua Washington , Simon Horman , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 085/224] gve: Cache link_speed value from device Date: Tue, 28 Mar 2023 16:41:21 +0200 Message-Id: <20230328142620.813987850@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230328142617.205414124@linuxfoundation.org> References: <20230328142617.205414124@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Joshua Washington [ Upstream commit 68c3e4fc8628b1487c965aabb29207249657eb5f ] The link speed is never changed for the uptime of a VM, and the current implementation sends an admin queue command for each call. Admin queue command invocations have nontrivial overhead (e.g., VM exits), which can be disruptive to users if triggered frequently. Our telemetry data shows that there are VMs that make frequent calls to this admin queue command. Caching the result of the original admin queue command would eliminate the need to send multiple admin queue commands on subsequent calls to retrieve link speed. Fixes: 7e074d5a76ca ("gve: Enable Link Speed Reporting in the driver.") Signed-off-by: Joshua Washington Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230321172332.91678-1-joshwash@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/google/gve/gve_ethtool.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c index 7b9a2d9d96243..38df602f2869c 100644 --- a/drivers/net/ethernet/google/gve/gve_ethtool.c +++ b/drivers/net/ethernet/google/gve/gve_ethtool.c @@ -535,7 +535,10 @@ static int gve_get_link_ksettings(struct net_device *netdev, struct ethtool_link_ksettings *cmd) { struct gve_priv *priv = netdev_priv(netdev); - int err = gve_adminq_report_link_speed(priv); + int err = 0; + + if (priv->link_speed == 0) + err = gve_adminq_report_link_speed(priv); cmd->base.speed = priv->link_speed; return err; -- 2.39.2