From patchwork Tue Jul 11 20:20:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 13309349 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 A2EAFEB64DD for ; Tue, 11 Jul 2023 20:21:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230018AbjGKUV2 (ORCPT ); Tue, 11 Jul 2023 16:21:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42524 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229987AbjGKUVZ (ORCPT ); Tue, 11 Jul 2023 16:21:25 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83BC210D4 for ; Tue, 11 Jul 2023 13:21:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=5FN0HiT2a6i6oQBEDqgGmkCDTbMkD96qK8TmIcdDOvU=; b=BzG7fNesDSv9f5c/jHckIpGYxr 1AjjHU4Ah6jva8EK1Xcg1/biocRXvpql2nETap2r1zt63XApMDK8MNuoMrkEge7p433afITqveoC3 Lh9PyA4r1OYCcI8kixo3vPG870zrKJVBOEc45zm+IEQoWThCsGK0JCfwO5zglXVRuurCxIV49tMb6 tlkYbLY36M0L1CpBIWxZD89hARza9OQ7yNWvq3+9zcyasAmecs0SbqtEGsAY8bVkyE7Y/8n3U9YG8 hOj3abiKh2aB7siI996/oscxpg5i29HTOtetWXWuMHJK8XmiAJaslK8w9KiTK8fuihRlHUcdFaRBh GJRAiejQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qJJqr-00G1Q6-EC; Tue, 11 Jul 2023 20:20:49 +0000 From: "Matthew Wilcox (Oracle)" To: linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , Arjun Roy , Eric Dumazet , Suren Baghdasaryan , linux-fsdevel@vger.kernel.org, Punit Agrawal Subject: [PATCH v2 1/9] Revert "tcp: Use per-vma locking for receive zerocopy" Date: Tue, 11 Jul 2023 21:20:39 +0100 Message-Id: <20230711202047.3818697-2-willy@infradead.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20230711202047.3818697-1-willy@infradead.org> References: <20230711202047.3818697-1-willy@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This reverts commit 7a7f094635349a7d0314364ad50bdeb770b6df4f. Reviewed-by: Suren Baghdasaryan --- MAINTAINERS | 1 - include/linux/net_mm.h | 17 ---------------- include/net/tcp.h | 1 - mm/memory.c | 7 +++---- net/ipv4/tcp.c | 45 ++++++++---------------------------------- 5 files changed, 11 insertions(+), 60 deletions(-) delete mode 100644 include/linux/net_mm.h diff --git a/MAINTAINERS b/MAINTAINERS index 18cd0ce2c7d2..00047800cff1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14816,7 +14816,6 @@ NETWORKING [TCP] M: Eric Dumazet L: netdev@vger.kernel.org S: Maintained -F: include/linux/net_mm.h F: include/linux/tcp.h F: include/net/tcp.h F: include/trace/events/tcp.h diff --git a/include/linux/net_mm.h b/include/linux/net_mm.h deleted file mode 100644 index b298998bd5a0..000000000000 --- a/include/linux/net_mm.h +++ /dev/null @@ -1,17 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -#ifdef CONFIG_MMU - -#ifdef CONFIG_INET -extern const struct vm_operations_struct tcp_vm_ops; -static inline bool vma_is_tcp(const struct vm_area_struct *vma) -{ - return vma->vm_ops == &tcp_vm_ops; -} -#else -static inline bool vma_is_tcp(const struct vm_area_struct *vma) -{ - return false; -} -#endif /* CONFIG_INET*/ - -#endif /* CONFIG_MMU */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 226bce6d1e8c..95e4507febed 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -45,7 +45,6 @@ #include #include #include -#include extern struct inet_hashinfo tcp_hashinfo; diff --git a/mm/memory.c b/mm/memory.c index 0a265ac6246e..2c7967632866 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -77,7 +77,6 @@ #include #include #include -#include #include @@ -5419,12 +5418,12 @@ struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, if (!vma) goto inval; - /* Only anonymous and tcp vmas are supported for now */ - if (!vma_is_anonymous(vma) && !vma_is_tcp(vma)) + /* Only anonymous vmas are supported for now */ + if (!vma_is_anonymous(vma)) goto inval; /* find_mergeable_anon_vma uses adjacent vmas which are not locked */ - if (!vma->anon_vma && !vma_is_tcp(vma)) + if (!vma->anon_vma) goto inval; if (!vma_start_read(vma)) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e03e08745308..1542de3f66f7 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1739,7 +1739,7 @@ void tcp_update_recv_tstamps(struct sk_buff *skb, } #ifdef CONFIG_MMU -const struct vm_operations_struct tcp_vm_ops = { +static const struct vm_operations_struct tcp_vm_ops = { }; int tcp_mmap(struct file *file, struct socket *sock, @@ -2038,34 +2038,6 @@ static void tcp_zc_finalize_rx_tstamp(struct sock *sk, } } -static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, - unsigned long address, - bool *mmap_locked) -{ - struct vm_area_struct *vma = NULL; - -#ifdef CONFIG_PER_VMA_LOCK - vma = lock_vma_under_rcu(mm, address); -#endif - if (vma) { - if (!vma_is_tcp(vma)) { - vma_end_read(vma); - return NULL; - } - *mmap_locked = false; - return vma; - } - - mmap_read_lock(mm); - vma = vma_lookup(mm, address); - if (!vma || !vma_is_tcp(vma)) { - mmap_read_unlock(mm); - return NULL; - } - *mmap_locked = true; - return vma; -} - #define TCP_ZEROCOPY_PAGE_BATCH_SIZE 32 static int tcp_zerocopy_receive(struct sock *sk, struct tcp_zerocopy_receive *zc, @@ -2083,7 +2055,6 @@ static int tcp_zerocopy_receive(struct sock *sk, u32 seq = tp->copied_seq; u32 total_bytes_to_map; int inq = tcp_inq(sk); - bool mmap_locked; int ret; zc->copybuf_len = 0; @@ -2108,10 +2079,13 @@ static int tcp_zerocopy_receive(struct sock *sk, return 0; } - vma = find_tcp_vma(current->mm, address, &mmap_locked); - if (!vma) - return -EINVAL; + mmap_read_lock(current->mm); + vma = vma_lookup(current->mm, address); + if (!vma || vma->vm_ops != &tcp_vm_ops) { + mmap_read_unlock(current->mm); + return -EINVAL; + } vma_len = min_t(unsigned long, zc->length, vma->vm_end - address); avail_len = min_t(u32, vma_len, inq); total_bytes_to_map = avail_len & ~(PAGE_SIZE - 1); @@ -2185,10 +2159,7 @@ static int tcp_zerocopy_receive(struct sock *sk, zc, total_bytes_to_map); } out: - if (mmap_locked) - mmap_read_unlock(current->mm); - else - vma_end_read(vma); + mmap_read_unlock(current->mm); /* Try to copy straggler data. */ if (!ret) copylen = tcp_zc_handle_leftover(zc, sk, skb, &seq, copybuf_len, tss);