From patchwork Mon Nov 8 11:49:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12608311 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE8BDC433F5 for ; Mon, 8 Nov 2021 11:49:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 824EC61181 for ; Mon, 8 Nov 2021 11:49:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239303AbhKHLwh (ORCPT ); Mon, 8 Nov 2021 06:52:37 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:33231 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231401AbhKHLwh (ORCPT ); Mon, 8 Nov 2021 06:52:37 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R181e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04426;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0Uvadc9._1636372191; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0Uvadc9._1636372191) by smtp.aliyun-inc.com(127.0.0.1); Mon, 08 Nov 2021 19:49:51 +0800 From: Xuan Zhuo To: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Cc: "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Jakub Kicinski Subject: [PATCH v4 0/3] virtio support cache indirect desc Date: Mon, 8 Nov 2021 19:49:48 +0800 Message-Id: <20211108114951.92862-1-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org If the VIRTIO_RING_F_INDIRECT_DESC negotiation succeeds, and the number of sgs used for sending packets is greater than 1. We must constantly call __kmalloc/kfree to allocate/release desc. In the case of extremely fast package delivery, the overhead cannot be ignored: 27.46% [kernel] [k] virtqueue_add 16.66% [kernel] [k] detach_buf_split 16.51% [kernel] [k] virtnet_xsk_xmit 14.04% [kernel] [k] virtqueue_add_outbuf 5.18% [kernel] [k] __kmalloc 4.08% [kernel] [k] kfree 2.80% [kernel] [k] virtqueue_get_buf_ctx 2.22% [kernel] [k] xsk_tx_peek_desc 2.08% [kernel] [k] memset_erms 0.83% [kernel] [k] virtqueue_kick_prepare 0.76% [kernel] [k] virtnet_xsk_run 0.62% [kernel] [k] __free_old_xmit_ptr 0.60% [kernel] [k] vring_map_one_sg 0.53% [kernel] [k] native_apic_mem_write 0.46% [kernel] [k] sg_next 0.43% [kernel] [k] sg_init_table 0.41% [kernel] [k] kmalloc_slab This patch adds a cache function to virtio to cache these allocated indirect desc instead of constantly allocating and releasing desc. v4: 1. Only allow desc cache when VIRTIO_RING_F_INDIRECT_DESC negotiation is successful 2. The desc cache threshold can be set for each virtqueue v3: pre-allocate per buffer indirect descriptors array v2: use struct list_head to cache the desc Xuan Zhuo (3): virtio: cache indirect desc for split virtio: cache indirect desc for packed virtio-net: enable virtio desc cache drivers/net/virtio_net.c | 12 ++- drivers/virtio/virtio_ring.c | 152 +++++++++++++++++++++++++++++++---- include/linux/virtio.h | 17 ++++ 3 files changed, 163 insertions(+), 18 deletions(-) Signed-off-by: Michael S. Tsirkin --- 2.31.0