From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mail19.linbit.com (LINBIT Mail Daemon) with ESMTP id 62B3B42017A for ; Sat, 24 Jun 2023 00:55:49 +0200 (CEST) From: David Howells To: netdev@vger.kernel.org Date: Fri, 23 Jun 2023 23:55:07 +0100 Message-ID: <20230623225513.2732256-11-dhowells@redhat.com> In-Reply-To: <20230623225513.2732256-1-dhowells@redhat.com> References: <20230623225513.2732256-1-dhowells@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Jens Axboe , linux-block@vger.kernel.org, Willem de Bruijn , David Ahern , linux-kernel@vger.kernel.org, Alexander Duyck , Philipp Reisner , David Howells , linux-mm@kvack.org, Eric Dumazet , Matthew Wilcox , Jakub Kicinski , Lars Ellenberg , Paolo Abeni , "David S. Miller" , drbd-dev@lists.linbit.com Subject: [Drbd-dev] [PATCH net-next v5 10/16] drbd: Use sendmsg(MSG_SPLICE_PAGES) rather than sendpage() List-Id: "*Coordination* of development, patches, contributions -- *Questions* \(even to developers\) go to drbd-user, please." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Use sendmsg() conditionally with MSG_SPLICE_PAGES in _drbd_send_page() rather than calling sendpage() or _drbd_no_send_page(). Signed-off-by: David Howells cc: Philipp Reisner cc: Lars Ellenberg cc: "Christoph Böhmwalder" cc: Jens Axboe cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: drbd-dev@lists.linbit.com cc: linux-block@vger.kernel.org cc: netdev@vger.kernel.org --- Notes: ver #4) - Don't look at msg.msg_iter after calling sendmsg. There's no guarantee it has changed. ver #2) - Wrap lines at 80. drivers/block/drbd/drbd_main.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 83987e7a5ef2..ea82d6733313 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -1540,6 +1540,8 @@ static int _drbd_send_page(struct drbd_peer_device *peer_device, struct page *pa int offset, size_t size, unsigned msg_flags) { struct socket *socket = peer_device->connection->data.socket; + struct msghdr msg = { .msg_flags = msg_flags, }; + struct bio_vec bvec; int len = size; int err = -EIO; @@ -1549,15 +1551,17 @@ static int _drbd_send_page(struct drbd_peer_device *peer_device, struct page *pa * put_page(); and would cause either a VM_BUG directly, or * __page_cache_release a page that would actually still be referenced * by someone, leading to some obscure delayed Oops somewhere else. */ - if (drbd_disable_sendpage || !sendpage_ok(page)) - return _drbd_no_send_page(peer_device, page, offset, size, msg_flags); + if (!drbd_disable_sendpage && sendpage_ok(page)) + msg.msg_flags |= MSG_NOSIGNAL | MSG_SPLICE_PAGES; - msg_flags |= MSG_NOSIGNAL; drbd_update_congested(peer_device->connection); do { int sent; - sent = socket->ops->sendpage(socket, page, offset, len, msg_flags); + bvec_set_page(&bvec, page, offset, len); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, len); + + sent = sock_sendmsg(socket, &msg); if (sent <= 0) { if (sent == -EAGAIN) { if (we_should_drop_the_connection(peer_device->connection, socket))