From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5EC2C282CE for ; Wed, 10 Apr 2019 11:43:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B92220820 for ; Wed, 10 Apr 2019 11:43:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731481AbfDJLnw (ORCPT ); Wed, 10 Apr 2019 07:43:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40538 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729949AbfDJLnw (ORCPT ); Wed, 10 Apr 2019 07:43:52 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 65180306D321; Wed, 10 Apr 2019 11:43:51 +0000 (UTC) Received: from firesoul.localdomain (ovpn-200-48.brq.redhat.com [10.40.200.48]) by smtp.corp.redhat.com (Postfix) with ESMTP id CF39110694E8; Wed, 10 Apr 2019 11:43:48 +0000 (UTC) Received: from [10.10.10.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id F393831256FC5; Wed, 10 Apr 2019 13:43:47 +0200 (CEST) Subject: [PATCH bpf-next 3/5] net: core: introduce build_skb_around From: Jesper Dangaard Brouer To: netdev@vger.kernel.org, Daniel Borkmann , Alexei Starovoitov , "David S. Miller" Cc: Ilias Apalodimas , bpf@vger.kernel.org, Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= , Jesper Dangaard Brouer Date: Wed, 10 Apr 2019 13:43:47 +0200 Message-ID: <155489662793.20826.5533583763088193882.stgit@firesoul> In-Reply-To: <155489659290.20826.1108770347511292618.stgit@firesoul> References: <155489659290.20826.1108770347511292618.stgit@firesoul> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Wed, 10 Apr 2019 11:43:51 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The function build_skb() also have the responsibility to allocate and clear the SKB structure. Introduce a new function build_skb_around(), that moves the responsibility of allocation and clearing to the caller. This allows caller to use kmem_cache (slab/slub) bulk allocation API. Next patch use this function combined with kmem_cache_alloc_bulk. Signed-off-by: Jesper Dangaard Brouer --- include/linux/skbuff.h | 2 + net/core/skbuff.c | 71 +++++++++++++++++++++++++++++++++++------------- 2 files changed, 54 insertions(+), 19 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 9027a8c4219f..c40ffab8a9b0 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1044,6 +1044,8 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags, int node); struct sk_buff *__build_skb(void *data, unsigned int frag_size); struct sk_buff *build_skb(void *data, unsigned int frag_size); +struct sk_buff *build_skb_around(struct sk_buff *skb, + void *data, unsigned int frag_size); /** * alloc_skb - allocate a network buffer diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4782f9354dd1..d904b6e5fe08 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -258,6 +258,33 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, } EXPORT_SYMBOL(__alloc_skb); +/* Caller must provide SKB that is memset cleared */ +static struct sk_buff *__build_skb_around(struct sk_buff *skb, + void *data, unsigned int frag_size) +{ + struct skb_shared_info *shinfo; + unsigned int size = frag_size ? : ksize(data); + + size -= SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + + /* Assumes caller memset cleared SKB */ + skb->truesize = SKB_TRUESIZE(size); + refcount_set(&skb->users, 1); + skb->head = data; + skb->data = data; + skb_reset_tail_pointer(skb); + skb->end = skb->tail + size; + skb->mac_header = (typeof(skb->mac_header))~0U; + skb->transport_header = (typeof(skb->transport_header))~0U; + + /* make sure we initialize shinfo sequentially */ + shinfo = skb_shinfo(skb); + memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); + atomic_set(&shinfo->dataref, 1); + + return skb; +} + /** * __build_skb - build a network buffer * @data: data buffer provided by caller @@ -279,32 +306,15 @@ EXPORT_SYMBOL(__alloc_skb); */ struct sk_buff *__build_skb(void *data, unsigned int frag_size) { - struct skb_shared_info *shinfo; struct sk_buff *skb; - unsigned int size = frag_size ? : ksize(data); skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC); - if (!skb) + if (unlikely(!skb)) return NULL; - size -= SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); - memset(skb, 0, offsetof(struct sk_buff, tail)); - skb->truesize = SKB_TRUESIZE(size); - refcount_set(&skb->users, 1); - skb->head = data; - skb->data = data; - skb_reset_tail_pointer(skb); - skb->end = skb->tail + size; - skb->mac_header = (typeof(skb->mac_header))~0U; - skb->transport_header = (typeof(skb->transport_header))~0U; - /* make sure we initialize shinfo sequentially */ - shinfo = skb_shinfo(skb); - memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); - atomic_set(&shinfo->dataref, 1); - - return skb; + return __build_skb_around(skb, data, frag_size); } /* build_skb() is wrapper over __build_skb(), that specifically @@ -325,6 +335,29 @@ struct sk_buff *build_skb(void *data, unsigned int frag_size) } EXPORT_SYMBOL(build_skb); +/** + * build_skb_around - build a network buffer around provided skb + * @skb: sk_buff provide by caller, must be memset cleared + * @data: data buffer provided by caller + * @frag_size: size of data, or 0 if head was kmalloced + */ +struct sk_buff *build_skb_around(struct sk_buff *skb, + void *data, unsigned int frag_size) +{ + if (unlikely(!skb)) + return NULL; + + skb = __build_skb_around(skb, data, frag_size); + + if (skb && frag_size) { + skb->head_frag = 1; + if (page_is_pfmemalloc(virt_to_head_page(data))) + skb->pfmemalloc = 1; + } + return skb; +} +EXPORT_SYMBOL(build_skb_around); + #define NAPI_SKB_CACHE_SIZE 64 struct napi_alloc_cache {