From patchwork Mon May 20 21:42:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Hopps X-Patchwork-Id: 13668684 X-Patchwork-Delegate: kuba@kernel.org Received: from smtp.chopps.org (smtp.chopps.org [54.88.81.56]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DCF6C13A24D for ; Mon, 20 May 2024 21:43:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.88.81.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716241427; cv=none; b=tgrKPcqiPwhes4PcDxKsEst45U16Od/7i5/4FPxouQsmrnf0s036sOXfSAdKo5uJKimyzzmpknW78KnZkwj1IzEnVrjM0jafIdSn9n0M8YJo9QPRJcvmbiG0LBUrrz8rl6G/+nXGxmagfzuOxohAficctJ685c7mAX9NElfSrAg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716241427; c=relaxed/simple; bh=XAddrshhJ8wbZNNVX/WdGr0E9UpAJTb+5YLzpKaOBgI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kV60BPuaRA0eoMY0aiUHW08gwatKYRcDz/kUBhnzvZ5vXGyT2nf1OI/J9BJjwsAzb8YfCS758obyOqEdIZHTp05cOjBtNC6IcedAxJlEc5UqJr0ljiiTC1QbFLbvBUlwMVapUV+Ov42Hfah+1uN2JhU+b/tWpB9eXmLjlDdqMo8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=chopps.org; spf=fail smtp.mailfrom=chopps.org; arc=none smtp.client-ip=54.88.81.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=chopps.org Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=chopps.org Received: from labnh.int.chopps.org (syn-172-222-091-149.res.spectrum.com [172.222.91.149]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by smtp.chopps.org (Postfix) with ESMTPSA id EB5CF7D12C; Mon, 20 May 2024 21:43:41 +0000 (UTC) From: Christian Hopps To: devel@linux-ipsec.org Cc: Steffen Klassert , netdev@vger.kernel.org, Christian Hopps , Christian Hopps Subject: [PATCH ipsec-next v2 10/17] xfrm: iptfs: share page fragments of inner packets Date: Mon, 20 May 2024 17:42:48 -0400 Message-ID: <20240520214255.2590923-11-chopps@chopps.org> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240520214255.2590923-1-chopps@chopps.org> References: <20240520214255.2590923-1-chopps@chopps.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org From: Christian Hopps When possible rather than appending secondary (aggregated) inner packets to the fragment list, share their page fragments with the outer IPTFS packet. This allows for more efficient packet transmission. Signed-off-by: Christian Hopps --- net/xfrm/xfrm_iptfs.c | 88 ++++++++++++++++++++++++++++++++++++++----- 1 file changed, 79 insertions(+), 9 deletions(-) diff --git a/net/xfrm/xfrm_iptfs.c b/net/xfrm/xfrm_iptfs.c index 561483fc83f9..87ba643edfb7 100644 --- a/net/xfrm/xfrm_iptfs.c +++ b/net/xfrm/xfrm_iptfs.c @@ -45,6 +45,24 @@ struct xfrm_iptfs_data { static u32 iptfs_get_inner_mtu(struct xfrm_state *x, int outer_mtu); static enum hrtimer_restart iptfs_delay_timer(struct hrtimer *me); +/* ================= */ +/* SK_BUFF Functions */ +/* ================= */ + +/** + * skb_head_to_frag() - initialize a skb_frag_t based on skb head data + * @skb: skb with the head data + * @frag: frag to initialize + */ +static void skb_head_to_frag(const struct sk_buff *skb, skb_frag_t *frag) +{ + struct page *page = virt_to_head_page(skb->data); + unsigned char *addr = (unsigned char *)page_address(page); + + BUG_ON(!skb->head_frag); + skb_frag_fill_page_desc(frag, page, skb->data - addr, skb_headlen(skb)); +} + /* ================================= */ /* IPTFS Sending (ingress) Functions */ /* ================================= */ @@ -262,14 +280,44 @@ static struct sk_buff **iptfs_rehome_fraglist(struct sk_buff **nextp, return nextp; } +static void iptfs_consume_frags(struct sk_buff *to, struct sk_buff *from) +{ + struct skb_shared_info *fromi = skb_shinfo(from); + struct skb_shared_info *toi = skb_shinfo(to); + unsigned int new_truesize; + + /* If we have data in a head page, grab it */ + if (!skb_headlen(from)) { + new_truesize = SKB_TRUESIZE(skb_end_offset(from)); + } else { + skb_head_to_frag(from, &toi->frags[toi->nr_frags]); + skb_frag_ref(to, toi->nr_frags++); + new_truesize = SKB_DATA_ALIGN(sizeof(struct sk_buff)); + } + + /* Move any other page fragments rather than copy */ + memcpy(&toi->frags[toi->nr_frags], fromi->frags, + sizeof(fromi->frags[0]) * fromi->nr_frags); + toi->nr_frags += fromi->nr_frags; + fromi->nr_frags = 0; + from->data_len = 0; + from->len = 0; + to->truesize += from->truesize - new_truesize; + from->truesize = new_truesize; + + /* We are done with this SKB */ + consume_skb(from); +} + static void iptfs_output_queued(struct xfrm_state *x, struct sk_buff_head *list) { struct xfrm_iptfs_data *xtfs = x->mode_data; struct sk_buff *skb, *skb2, **nextp; - struct skb_shared_info *shi; + struct skb_shared_info *shi, *shi2; while ((skb = __skb_dequeue(list))) { u32 mtu = iptfs_get_cur_pmtu(x, xtfs, skb); + bool share_ok = true; int remaining; /* protocol comes to us cleared sometimes */ @@ -314,7 +362,7 @@ static void iptfs_output_queued(struct xfrm_state *x, struct sk_buff_head *list) /* Re-home (un-nest) nested fragment lists. We need to do this * b/c we will simply be appending any following aggregated - * inner packets to the frag list. + * inner packets using the frag list. */ shi = skb_shinfo(skb); nextp = &shi->frag_list; @@ -326,6 +374,9 @@ static void iptfs_output_queued(struct xfrm_state *x, struct sk_buff_head *list) nextp = &(*nextp)->next; } + if (shi->frag_list || skb_cloned(skb) || skb_shared(skb)) + share_ok = false; + /* See if we have enough space to simply append. * * NOTE: Maybe do not append if we will be mis-aligned, @@ -351,18 +402,37 @@ static void iptfs_output_queued(struct xfrm_state *x, struct sk_buff_head *list) } } + /* skb->pp_recycle is passed to __skb_flag_unref for all + * frag pages so we can only share pages with skb's who + * match ourselves. + */ + shi2 = skb_shinfo(skb2); + if (share_ok && + (shi2->frag_list || + (!skb2->head_frag && skb_headlen(skb)) || + skb->pp_recycle != skb2->pp_recycle || + skb_zcopy(skb2) || + (shi->nr_frags + shi2->nr_frags + 1 > + MAX_SKB_FRAGS))) + share_ok = false; + /* Do accounting */ skb->data_len += skb2->len; skb->len += skb2->len; remaining -= skb2->len; - /* Append to the frag_list */ - *nextp = skb2; - nextp = &skb2->next; - BUG_ON(*nextp); - if (skb_has_frag_list(skb2)) - nextp = iptfs_rehome_fraglist(nextp, skb2); - skb->truesize += skb2->truesize; + if (share_ok) { + iptfs_consume_frags(skb, skb2); + } else { + /* Append to the frag_list */ + *nextp = skb2; + nextp = &skb2->next; + BUG_ON(*nextp); + if (skb_has_frag_list(skb2)) + nextp = iptfs_rehome_fraglist(nextp, + skb2); + skb->truesize += skb2->truesize; + } } xfrm_output(NULL, skb);