From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: [net PATCH v3 2/5] net: virtio: wrap rtnl_lock in test for calling with lock already held Date: Thu, 12 Jan 2017 18:51:00 -0800 Message-ID: <20170113025100.4535.35887.stgit@john-Precision-Tower-5810> References: <20170113024908.4535.8835.stgit@john-Precision-Tower-5810> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: john.r.fastabend@intel.com, netdev@vger.kernel.org, john.fastabend@gmail.com, alexei.starovoitov@gmail.com, daniel@iogearbox.net To: jasowang@redhat.com, mst@redhat.com Return-path: Received: from mail-pf0-f196.google.com ([209.85.192.196]:36113 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751049AbdAMCvS (ORCPT ); Thu, 12 Jan 2017 21:51:18 -0500 Received: by mail-pf0-f196.google.com with SMTP id b22so6032584pfd.3 for ; Thu, 12 Jan 2017 18:51:18 -0800 (PST) In-Reply-To: <20170113024908.4535.8835.stgit@john-Precision-Tower-5810> Sender: netdev-owner@vger.kernel.org List-ID: For XDP use case and to allow ethtool reset tests it is useful to be able to use reset routines from contexts where rtnl lock is already held. Signed-off-by: John Fastabend --- drivers/net/virtio_net.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index d97bb71..43cb2e0 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1864,12 +1864,13 @@ static void virtnet_free_queues(struct virtnet_info *vi) kfree(vi->sq); } -static void free_receive_bufs(struct virtnet_info *vi) +static void free_receive_bufs(struct virtnet_info *vi, bool need_lock) { struct bpf_prog *old_prog; int i; - rtnl_lock(); + if (need_lock) + rtnl_lock(); for (i = 0; i < vi->max_queue_pairs; i++) { while (vi->rq[i].pages) __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0); @@ -1879,7 +1880,8 @@ static void free_receive_bufs(struct virtnet_info *vi) if (old_prog) bpf_prog_put(old_prog); } - rtnl_unlock(); + if (need_lock) + rtnl_unlock(); } static void free_receive_page_frags(struct virtnet_info *vi) @@ -2351,14 +2353,14 @@ static int virtnet_probe(struct virtio_device *vdev) return err; } -static void remove_vq_common(struct virtnet_info *vi) +static void remove_vq_common(struct virtnet_info *vi, bool lock) { vi->vdev->config->reset(vi->vdev); /* Free unused buffers in both send and recv, if any. */ free_unused_bufs(vi); - free_receive_bufs(vi); + free_receive_bufs(vi, lock); free_receive_page_frags(vi); @@ -2376,7 +2378,7 @@ static void virtnet_remove(struct virtio_device *vdev) unregister_netdev(vi->dev); - remove_vq_common(vi); + remove_vq_common(vi, true); free_percpu(vi->stats); free_netdev(vi->dev); @@ -2401,7 +2403,7 @@ static int virtnet_freeze(struct virtio_device *vdev) napi_disable(&vi->rq[i].napi); } - remove_vq_common(vi); + remove_vq_common(vi, true); return 0; }