From patchwork Sat Apr 1 17:26:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Michal Schmidt X-Patchwork-Id: 13197167 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 411C0C76196 for ; Sat, 1 Apr 2023 17:28:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229529AbjDAR2R (ORCPT ); Sat, 1 Apr 2023 13:28:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229984AbjDAR2P (ORCPT ); Sat, 1 Apr 2023 13:28:15 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 606541B368 for ; Sat, 1 Apr 2023 10:27:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1680370050; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6x9JHpIA3PUU98RhwvPPH7uduxmtkgeeOAzyRa/9hgc=; b=HvY7o6C8InVlXCcoVdzC5h9yS0IMmM2UjepHYuf7Pxre949xT6WOykCCPuCJvn2cgfN6VW I/yOqtceIvjTRagnJXN9+L5P1fb1lh4yIBwlUa2cPMXYNmI6PW8+WehJ5XdkQ9MoY903wa Z2K3vcjUVAT2XL/VUWW7zyMfK7djy28= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-221-1Zk0PcwAOyC9okto5OV-gg-1; Sat, 01 Apr 2023 13:27:25 -0400 X-MC-Unique: 1Zk0PcwAOyC9okto5OV-gg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7790A811E7C; Sat, 1 Apr 2023 17:27:24 +0000 (UTC) Received: from toolbox.redhat.com (ovpn-192-6.brq.redhat.com [10.40.192.6]) by smtp.corp.redhat.com (Postfix) with ESMTP id 679FB40C83A9; Sat, 1 Apr 2023 17:27:22 +0000 (UTC) From: Michal Schmidt To: intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org, Jesse Brandeburg , Tony Nguyen , Michal Michalik , Arkadiusz Kubalewski , Karol Kolacinski , Petr Oros Subject: [PATCH net-next 2/4] ice: sleep, don't busy-wait, for sq_cmd_timeout Date: Sat, 1 Apr 2023 19:26:57 +0200 Message-Id: <20230401172659.38508-3-mschmidt@redhat.com> In-Reply-To: <20230401172659.38508-1-mschmidt@redhat.com> References: <20230401172659.38508-1-mschmidt@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The driver polls for ice_sq_done() with a 100 µs period for up to 1 s and it uses udelay to do that. Let's use usleep_range instead. We know sleeping is allowed here, because we're holding a mutex (cq->sq_lock). To preserve the total max waiting time, measure cq->sq_cmd_timeout in jiffies. The sq_cmd_timeout is referenced also in ice_release_res(), but there the polling period is 1 ms (i.e. 10 times longer). Since the timeout was expressed in terms of the number of loops, the total timeout in this function is 10 s. I do not know if this is intentional. This patch keeps it. The patch lowers the CPU usage of the ice-gnss- kernel thread on my system from ~8 % to less than 1 %. I saw a report of high CPU usage with ptp4l where the busy-waiting in ice_sq_send_cmd dominated the profile. The patch should help with that. Signed-off-by: Michal Schmidt --- drivers/net/ethernet/intel/ice/ice_common.c | 14 +++++++------- drivers/net/ethernet/intel/ice/ice_controlq.c | 9 +++++---- drivers/net/ethernet/intel/ice/ice_controlq.h | 2 +- 3 files changed, 13 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_common.c b/drivers/net/ethernet/intel/ice/ice_common.c index c2fda4fa4188..14cffe49fa8c 100644 --- a/drivers/net/ethernet/intel/ice/ice_common.c +++ b/drivers/net/ethernet/intel/ice/ice_common.c @@ -1992,19 +1992,19 @@ ice_acquire_res(struct ice_hw *hw, enum ice_aq_res_ids res, */ void ice_release_res(struct ice_hw *hw, enum ice_aq_res_ids res) { - u32 total_delay = 0; + unsigned long timeout; int status; - status = ice_aq_release_res(hw, res, 0, NULL); - /* there are some rare cases when trying to release the resource * results in an admin queue timeout, so handle them correctly */ - while ((status == -EIO) && (total_delay < hw->adminq.sq_cmd_timeout)) { - mdelay(1); + timeout = jiffies + 10 * hw->adminq.sq_cmd_timeout; + do { status = ice_aq_release_res(hw, res, 0, NULL); - total_delay++; - } + if (status != -EIO) + break; + usleep_range(1000, 2000); + } while (time_before(jiffies, timeout)); } /** diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.c b/drivers/net/ethernet/intel/ice/ice_controlq.c index 6bcfee295991..10125e8aa555 100644 --- a/drivers/net/ethernet/intel/ice/ice_controlq.c +++ b/drivers/net/ethernet/intel/ice/ice_controlq.c @@ -967,7 +967,7 @@ ice_sq_send_cmd(struct ice_hw *hw, struct ice_ctl_q_info *cq, struct ice_aq_desc *desc_on_ring; bool cmd_completed = false; struct ice_sq_cd *details; - u32 total_delay = 0; + unsigned long timeout; int status = 0; u16 retval = 0; u32 val = 0; @@ -1060,13 +1060,14 @@ ice_sq_send_cmd(struct ice_hw *hw, struct ice_ctl_q_info *cq, cq->sq.next_to_use = 0; wr32(hw, cq->sq.tail, cq->sq.next_to_use); + timeout = jiffies + cq->sq_cmd_timeout; do { if (ice_sq_done(hw, cq)) break; - udelay(ICE_CTL_Q_SQ_CMD_USEC); - total_delay++; - } while (total_delay < cq->sq_cmd_timeout); + usleep_range(ICE_CTL_Q_SQ_CMD_USEC, + ICE_CTL_Q_SQ_CMD_USEC * 3 / 2); + } while (time_before(jiffies, timeout)); /* if ready, copy the desc back to temp */ if (ice_sq_done(hw, cq)) { diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.h b/drivers/net/ethernet/intel/ice/ice_controlq.h index c07e9cc9fc6e..f2d3b115ae0b 100644 --- a/drivers/net/ethernet/intel/ice/ice_controlq.h +++ b/drivers/net/ethernet/intel/ice/ice_controlq.h @@ -34,7 +34,7 @@ enum ice_ctl_q { }; /* Control Queue timeout settings - max delay 1s */ -#define ICE_CTL_Q_SQ_CMD_TIMEOUT 10000 /* Count 10000 times */ +#define ICE_CTL_Q_SQ_CMD_TIMEOUT HZ /* Wait max 1s */ #define ICE_CTL_Q_SQ_CMD_USEC 100 /* Check every 100usec */ #define ICE_CTL_Q_ADMIN_INIT_TIMEOUT 10 /* Count 10 times */ #define ICE_CTL_Q_ADMIN_INIT_MSEC 100 /* Check every 100msec */