From nobody Fri Sep 20 09:53:58 2024 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 33F0FCA0ECA for ; Tue, 12 Sep 2023 08:34:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232565AbjILIez (ORCPT ); Tue, 12 Sep 2023 04:34:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232084AbjILIew (ORCPT ); Tue, 12 Sep 2023 04:34:52 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D8DEB9; Tue, 12 Sep 2023 01:34:47 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RlGxy23blzJrxn; Tue, 12 Sep 2023 16:31:02 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:44 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Guillaume Tucker , Jesper Dangaard Brouer , Ilias Apalodimas , Eric Dumazet Subject: [PATCH net-next v8 1/6] page_pool: frag API support for 32-bit arch with 64-bit DMA Date: Tue, 12 Sep 2023 16:31:20 +0800 Message-ID: <20230912083126.65484-2-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently page_pool_alloc_frag() is not supported in 32-bit arch with 64-bit DMA because of the overlap issue between pp_frag_count and dma_addr_upper in 'struct page' for those arches, which seems to be quite common, see [1], which means driver may need to handle it when using frag API. It is assumed that the combination of the above arch with an address space >16TB does not exist, as all those arches have 64b equivalent, it seems logical to use the 64b version for a system with a large address space. It is also assumed that dma address is page aligned when we are dma mapping a page aliged buffer, see [2]. That means we're storing 12 bits of 0 at the lower end for a dma address, we can reuse those bits for the above arches to support 32b+12b, which is 16TB of memory. If we make a wrong assumption, a warning is emitted so that user can report to us. 1. https://lore.kernel.org/all/20211117075652.58299-1-linyunsheng@huawei.co= m/ 2. https://lore.kernel.org/all/20230818145145.4b357c89@kernel.org/ Signed-off-by: Jakub Kicinski Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin CC: Guillaume Tucker --- include/linux/mm_types.h | 13 +------------ include/net/page_pool/helpers.h | 20 ++++++++++++++------ net/core/page_pool.c | 14 +++++++++----- 3 files changed, 24 insertions(+), 23 deletions(-) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 36c5b43999e6..74b49c4c7a52 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -125,18 +125,7 @@ struct page { struct page_pool *pp; unsigned long _pp_mapping_pad; unsigned long dma_addr; - union { - /** - * dma_addr_upper: might require a 64-bit - * value on 32-bit architectures. - */ - unsigned long dma_addr_upper; - /** - * For frag page support, not supported in - * 32-bit architectures with 64-bit DMA. - */ - atomic_long_t pp_frag_count; - }; + atomic_long_t pp_frag_count; }; struct { /* Tail pages of compound page */ unsigned long compound_head; /* Bit zero is set */ diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helper= s.h index 94231533a369..8e1c85de4995 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -197,7 +197,7 @@ static inline void page_pool_recycle_direct(struct page= _pool *pool, page_pool_put_full_page(pool, page, true); } =20 -#define PAGE_POOL_DMA_USE_PP_FRAG_COUNT \ +#define PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA \ (sizeof(dma_addr_t) > sizeof(unsigned long)) =20 /** @@ -211,17 +211,25 @@ static inline dma_addr_t page_pool_get_dma_addr(struc= t page *page) { dma_addr_t ret =3D page->dma_addr; =20 - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) - ret |=3D (dma_addr_t)page->dma_addr_upper << 16 << 16; + if (PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA) + ret <<=3D PAGE_SHIFT; =20 return ret; } =20 -static inline void page_pool_set_dma_addr(struct page *page, dma_addr_t ad= dr) +static inline bool page_pool_set_dma_addr(struct page *page, dma_addr_t ad= dr) { + if (PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA) { + page->dma_addr =3D addr >> PAGE_SHIFT; + + /* We assume page alignment to shave off bottom bits, + * if this "compression" doesn't work we need to drop. + */ + return addr !=3D (dma_addr_t)page->dma_addr << PAGE_SHIFT; + } + page->dma_addr =3D addr; - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) - page->dma_addr_upper =3D upper_32_bits(addr); + return false; } =20 static inline bool page_pool_put(struct page_pool *pool) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 77cb75e63aca..8a9868ea5067 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -211,10 +211,6 @@ static int page_pool_init(struct page_pool *pool, */ } =20 - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT && - pool->p.flags & PP_FLAG_PAGE_FRAG) - return -EINVAL; - #ifdef CONFIG_PAGE_POOL_STATS pool->recycle_stats =3D alloc_percpu(struct page_pool_recycle_stats); if (!pool->recycle_stats) @@ -359,12 +355,20 @@ static bool page_pool_dma_map(struct page_pool *pool,= struct page *page) if (dma_mapping_error(pool->p.dev, dma)) return false; =20 - page_pool_set_dma_addr(page, dma); + if (page_pool_set_dma_addr(page, dma)) + goto unmap_failed; =20 if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) page_pool_dma_sync_for_device(pool, page, pool->p.max_len); =20 return true; + +unmap_failed: + WARN_ON_ONCE("unexpected DMA address, please report to netdev@"); + dma_unmap_page_attrs(pool->p.dev, dma, + PAGE_SIZE << pool->p.order, pool->p.dma_dir, + DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING); + return false; } =20 static void page_pool_set_pp_info(struct page_pool *pool, --=20 2.33.0 From nobody Fri Sep 20 09:53:58 2024 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 6007CCA0EC3 for ; Tue, 12 Sep 2023 08:34:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232774AbjILIe6 (ORCPT ); Tue, 12 Sep 2023 04:34:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232665AbjILIew (ORCPT ); Tue, 12 Sep 2023 04:34:52 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55DE4BF; Tue, 12 Sep 2023 01:34:48 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4RlH022J78zrSnR; Tue, 12 Sep 2023 16:32:50 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:46 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Jesper Dangaard Brouer , Ilias Apalodimas , Eric Dumazet Subject: [PATCH net-next v8 2/6] page_pool: unify frag_count handling in page_pool_is_last_frag() Date: Tue, 12 Sep 2023 16:31:21 +0800 Message-ID: <20230912083126.65484-3-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently when page_pool_create() is called with PP_FLAG_PAGE_FRAG flag, page_pool_alloc_pages() is only allowed to be called under the below constraints: 1. page_pool_fragment_page() need to be called to setup page->pp_frag_count immediately. 2. page_pool_defrag_page() often need to be called to drain the page->pp_frag_count when there is no more user will be holding on to that page. Those constraints exist in order to support a page to be split into multi frags. And those constraints have some overhead because of the cache line dirtying/bouncing and atomic update. Those constraints are unavoidable for case when we need a page to be split into more than one frag, but there is also case that we want to avoid the above constraints and their overhead when a page can't be split as it can only hold a big frag as requested by user, depending on different use cases: use case 1: allocate page without page splitting. use case 2: allocate page with page splitting. use case 3: allocate page with or without page splitting depending on the frag size. Currently page pool only provide page_pool_alloc_pages() and page_pool_alloc_frag() API to enable the 1 & 2 separately, so we can not use a combination of 1 & 2 to enable 3, it is not possible yet because of the per page_pool flag PP_FLAG_PAGE_FRAG. So in order to allow allocating unsplit page without the overhead of split page while still allow allocating split page we need to remove the per page_pool flag in page_pool_is_last_frag(), as best as I can think of, it seems there are two methods as below: 1. Add per page flag/bit to indicate a page is split or not, which means we might need to update that flag/bit everytime the page is recycled, dirtying the cache line of 'struct page' for use case 1. 2. Unify the page->pp_frag_count handling for both split and unsplit page by assuming all pages in the page pool is split into a big frag initially. As page pool already supports use case 1 without dirtying the cache line of 'struct page' whenever a page is recyclable, we need to support the above use case 3 with minimal overhead, especially not adding any noticeable overhead for use case 1, and we are already doing an optimization by not updating pp_frag_count in page_pool_defrag_page() for the last frag user, this patch chooses to unify the pp_frag_count handling to support the above use case 3. Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin --- include/net/page_pool/helpers.h | 48 ++++++++++++++++++++++++--------- net/core/page_pool.c | 10 ++++++- 2 files changed, 44 insertions(+), 14 deletions(-) diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helper= s.h index 8e1c85de4995..0ec81b91bed8 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -115,28 +115,50 @@ static inline long page_pool_defrag_page(struct page = *page, long nr) long ret; =20 /* If nr =3D=3D pp_frag_count then we have cleared all remaining - * references to the page. No need to actually overwrite it, instead - * we can leave this to be overwritten by the calling function. + * references to the page: + * 1. 'n =3D=3D 1': no need to actually overwrite it. + * 2. 'n !=3D 1': overwrite it with one, which is the rare case + * for frag draining. * - * The main advantage to doing this is that an atomic_read is - * generally a much cheaper operation than an atomic update, - * especially when dealing with a page that may be partitioned - * into only 2 or 3 pieces. + * The main advantage to doing this is that not only we avoid a + * atomic update, as an atomic_read is generally a much cheaper + * operation than an atomic update, especially when dealing with + * a page that may be partitioned into only 2 or 3 pieces; but + * also unify the frag and non-frag handling by ensuring all + * pages have been split into one big frag initially, and only + * overwrite it when the page is split into more than one frag. */ - if (atomic_long_read(&page->pp_frag_count) =3D=3D nr) + if (atomic_long_read(&page->pp_frag_count) =3D=3D nr) { + /* As we have ensured nr is always one for constant case + * using the BUILD_BUG_ON(), only need to handle the + * non-constant case here for frag count draining, which + * is a rare case. + */ + BUILD_BUG_ON(__builtin_constant_p(nr) && nr !=3D 1); + if (!__builtin_constant_p(nr)) + atomic_long_set(&page->pp_frag_count, 1); + return 0; + } =20 ret =3D atomic_long_sub_return(nr, &page->pp_frag_count); WARN_ON(ret < 0); + + /* We are the last user here too, reset frag count back to 1 to + * ensure all pages have been split into one big frag initially, + * this should be the rare case when the last two frag users call + * page_pool_defrag_page() currently. + */ + if (unlikely(!ret)) + atomic_long_set(&page->pp_frag_count, 1); + return ret; } =20 -static inline bool page_pool_is_last_frag(struct page_pool *pool, - struct page *page) +static inline bool page_pool_is_last_frag(struct page *page) { - /* If fragments aren't enabled or count is 0 we were the last user */ - return !(pool->p.flags & PP_FLAG_PAGE_FRAG) || - (page_pool_defrag_page(page, 1) =3D=3D 0); + /* If page_pool_defrag_page() returns 0, we were the last user */ + return page_pool_defrag_page(page, 1) =3D=3D 0; } =20 /** @@ -161,7 +183,7 @@ static inline void page_pool_put_page(struct page_pool = *pool, * allow registering MEM_TYPE_PAGE_POOL, but shield linker. */ #ifdef CONFIG_PAGE_POOL - if (!page_pool_is_last_frag(pool, page)) + if (!page_pool_is_last_frag(page)) return; =20 page_pool_put_defragged_page(pool, page, dma_sync_size, allow_direct); diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 8a9868ea5067..403b6df2e144 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -376,6 +376,14 @@ static void page_pool_set_pp_info(struct page_pool *po= ol, { page->pp =3D pool; page->pp_magic |=3D PP_SIGNATURE; + + /* Ensuring all pages have been split into one big frag initially: + * page_pool_set_pp_info() is only called once for every page when it + * is allocated from the page allocator and page_pool_fragment_page() + * is dirtying the same cache line as the page->pp_magic above, so + * the overhead is negligible. + */ + page_pool_fragment_page(page, 1); if (pool->p.init_callback) pool->p.init_callback(page, pool->p.init_arg); } @@ -672,7 +680,7 @@ void page_pool_put_page_bulk(struct page_pool *pool, vo= id **data, struct page *page =3D virt_to_head_page(data[i]); =20 /* It is not the last user for the page frag case */ - if (!page_pool_is_last_frag(pool, page)) + if (!page_pool_is_last_frag(page)) continue; =20 page =3D __page_pool_put_page(pool, page, -1, false); --=20 2.33.0 From nobody Fri Sep 20 09:53:58 2024 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 B7E64CA0ED5 for ; Tue, 12 Sep 2023 08:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232787AbjILIfC (ORCPT ); Tue, 12 Sep 2023 04:35:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232753AbjILIey (ORCPT ); Tue, 12 Sep 2023 04:34:54 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08707E7A; Tue, 12 Sep 2023 01:34:50 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4RlGyK6yWJzMlHD; Tue, 12 Sep 2023 16:31:21 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:48 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Michael Chan , Eric Dumazet , Yisen Zhuang , Salil Mehta , Sunil Goutham , Geetha sowjanya , Subbaraya Sundeep , hariprasad , Saeed Mahameed , Leon Romanovsky , Felix Fietkau , Ryder Lee , Shayne Chen , Sean Wang , Kalle Valo , Matthias Brugger , AngeloGioacchino Del Regno , Jesper Dangaard Brouer , Ilias Apalodimas , , , , Subject: [PATCH net-next v8 3/6] page_pool: remove PP_FLAG_PAGE_FRAG Date: Tue, 12 Sep 2023 16:31:22 +0800 Message-ID: <20230912083126.65484-4-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" PP_FLAG_PAGE_FRAG is not really needed after pp_frag_count handling is unified and page_pool_alloc_frag() is supported in 32-bit arch with 64-bit DMA, so remove it. Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 -- drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 3 +-- drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c | 2 +- drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 2 +- drivers/net/wireless/mediatek/mt76/mac80211.c | 2 +- include/net/page_pool/types.h | 6 ++---- net/core/page_pool.c | 3 +-- net/core/skbuff.c | 2 +- 8 files changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethern= et/broadcom/bnxt/bnxt.c index 5cc0dbe12132..8c2e455f534d 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -3194,8 +3194,6 @@ static int bnxt_alloc_rx_page_pool(struct bnxt *bp, pp.dma_dir =3D bp->rx_dir; pp.max_len =3D PAGE_SIZE; pp.flags =3D PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV; - if (PAGE_SIZE > BNXT_RX_PAGE_SIZE) - pp.flags |=3D PP_FLAG_PAGE_FRAG; =20 rxr->page_pool =3D page_pool_create(&pp); if (IS_ERR(rxr->page_pool)) { diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/= ethernet/hisilicon/hns3/hns3_enet.c index b4895c7b3efd..b9b66c1018d7 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -4931,8 +4931,7 @@ static void hns3_put_ring_config(struct hns3_nic_priv= *priv) static void hns3_alloc_page_pool(struct hns3_enet_ring *ring) { struct page_pool_params pp_params =3D { - .flags =3D PP_FLAG_DMA_MAP | PP_FLAG_PAGE_FRAG | - PP_FLAG_DMA_SYNC_DEV, + .flags =3D PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV, .order =3D hns3_page_order(ring), .pool_size =3D ring->desc_num * hns3_buf_size(ring) / (PAGE_SIZE << hns3_page_order(ring)), diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c b/dri= vers/net/ethernet/marvell/octeontx2/nic/otx2_common.c index 8511906cb4e2..84573609e41b 100644 --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c @@ -1434,7 +1434,7 @@ int otx2_pool_init(struct otx2_nic *pfvf, u16 pool_id, return 0; } =20 - pp_params.flags =3D PP_FLAG_PAGE_FRAG | PP_FLAG_DMA_MAP; + pp_params.flags =3D PP_FLAG_DMA_MAP; pp_params.pool_size =3D min(OTX2_PAGE_POOL_SZ, numptrs); pp_params.nid =3D NUMA_NO_NODE; pp_params.dev =3D pfvf->dev; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/ne= t/ethernet/mellanox/mlx5/core/en_main.c index a2ae791538ed..f3cf13a8bb19 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -834,7 +834,7 @@ static int mlx5e_alloc_rq(struct mlx5e_params *params, struct page_pool_params pp_params =3D { 0 }; =20 pp_params.order =3D 0; - pp_params.flags =3D PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV | PP_FLAG= _PAGE_FRAG; + pp_params.flags =3D PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV; pp_params.pool_size =3D pool_size; pp_params.nid =3D node; pp_params.dev =3D rq->pdev; diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wi= reless/mediatek/mt76/mac80211.c index d158320bc15d..fe7cc67b7ee2 100644 --- a/drivers/net/wireless/mediatek/mt76/mac80211.c +++ b/drivers/net/wireless/mediatek/mt76/mac80211.c @@ -566,7 +566,7 @@ int mt76_create_page_pool(struct mt76_dev *dev, struct = mt76_queue *q) { struct page_pool_params pp_params =3D { .order =3D 0, - .flags =3D PP_FLAG_PAGE_FRAG, + .flags =3D 0, .nid =3D NUMA_NO_NODE, .dev =3D dev->dma_dev, }; diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h index 887e7946a597..6fc5134095ed 100644 --- a/include/net/page_pool/types.h +++ b/include/net/page_pool/types.h @@ -17,10 +17,8 @@ * Please note DMA-sync-for-CPU is still * device driver responsibility */ -#define PP_FLAG_PAGE_FRAG BIT(2) /* for page frag feature */ #define PP_FLAG_ALL (PP_FLAG_DMA_MAP |\ - PP_FLAG_DMA_SYNC_DEV |\ - PP_FLAG_PAGE_FRAG) + PP_FLAG_DMA_SYNC_DEV) =20 /* * Fast allocation side cache array/stack @@ -45,7 +43,7 @@ struct pp_alloc_cache { =20 /** * struct page_pool_params - page pool parameters - * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV, PP_FLAG_PAGE_FRAG + * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV * @order: 2^order pages on allocation * @pool_size: size of the ptr_ring * @nid: NUMA node id to allocate from pages from diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 403b6df2e144..1927b9c36c23 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -756,8 +756,7 @@ struct page *page_pool_alloc_frag(struct page_pool *poo= l, unsigned int max_size =3D PAGE_SIZE << pool->p.order; struct page *page =3D pool->frag_page; =20 - if (WARN_ON(!(pool->p.flags & PP_FLAG_PAGE_FRAG) || - size > max_size)) + if (WARN_ON(size > max_size)) return NULL; =20 size =3D ALIGN(size, dma_get_cache_alignment()); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4eaf7ed0d1f4..a5f98b292e03 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5748,7 +5748,7 @@ bool skb_try_coalesce(struct sk_buff *to, struct sk_b= uff *from, /* In general, avoid mixing page_pool and non-page_pool allocated * pages within the same SKB. Additionally avoid dealing with clones * with page_pool pages, in case the SKB is using page_pool fragment - * references (PP_FLAG_PAGE_FRAG). Since we only take full page + * references (page_pool_alloc_frag()). Since we only take full page * references for cloned SKBs at the moment that would result in * inconsistent reference counts. * In theory we could take full references if @from is cloned and --=20 2.33.0 From nobody Fri Sep 20 09:53:58 2024 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 92210CA0EC3 for ; Tue, 12 Sep 2023 08:35:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232760AbjILIfJ (ORCPT ); Tue, 12 Sep 2023 04:35:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232762AbjILIe4 (ORCPT ); Tue, 12 Sep 2023 04:34:56 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AC8FB10C8; Tue, 12 Sep 2023 01:34:51 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RlGz73HGrzVkf4; Tue, 12 Sep 2023 16:32:03 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:49 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Jesper Dangaard Brouer , Ilias Apalodimas , Eric Dumazet Subject: [PATCH net-next v8 4/6] page_pool: introduce page_pool[_cache]_alloc() API Date: Tue, 12 Sep 2023 16:31:23 +0800 Message-ID: <20230912083126.65484-5-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently page pool supports the below use cases: use case 1: allocate page without page splitting using page_pool_alloc_pages() API if the driver knows that the memory it need is always bigger than half of the page allocated from page pool. use case 2: allocate page frag with page splitting using page_pool_alloc_frag() API if the driver knows that the memory it need is always smaller than or equal to the half of the page allocated from page pool. There is emerging use case [1] & [2] that is a mix of the above two case: the driver doesn't know the size of memory it need beforehand, so the driver may use something like below to allocate memory with least memory utilization and performance penalty: if (size << 1 > max_size) page =3D page_pool_alloc_pages(); else page =3D page_pool_alloc_frag(); To avoid the driver doing something like above, add the page_pool[_cache]_alloc() API to support the above use case, and update the true size of memory that is acctually allocated by updating '*size' back to the driver in order to avoid exacerbating truesize underestimate problem. Rename page_pool_free() which is used in the destroy process to __page_pool_destroy() to avoid confusion with the newly added API. 1. https://lore.kernel.org/all/d3ae6bd3537fbce379382ac6a42f67e22f27ece2.168= 3896626.git.lorenzo@kernel.org/ 2. https://lore.kernel.org/all/20230526054621.18371-3-liangchen.linux@gmail= .com/ Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin --- include/net/page_pool/helpers.h | 65 +++++++++++++++++++++++++++++++++ net/core/page_pool.c | 4 +- 2 files changed, 67 insertions(+), 2 deletions(-) diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helper= s.h index 0ec81b91bed8..c0e6c7d1b219 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -82,6 +82,65 @@ static inline struct page *page_pool_dev_alloc_frag(stru= ct page_pool *pool, return page_pool_alloc_frag(pool, offset, size, gfp); } =20 +static inline struct page *page_pool_alloc(struct page_pool *pool, + unsigned int *offset, + unsigned int *size, gfp_t gfp) +{ + unsigned int max_size =3D PAGE_SIZE << pool->p.order; + struct page *page; + + if ((*size << 1) > max_size) { + *size =3D max_size; + *offset =3D 0; + return page_pool_alloc_pages(pool, gfp); + } + + page =3D page_pool_alloc_frag(pool, offset, *size, gfp); + if (unlikely(!page)) + return NULL; + + /* There is very likely not enough space for another frag, so append the + * remaining size to the current frag to avoid truesize underestimate + * problem. + */ + if (pool->frag_offset + *size > max_size) { + *size =3D max_size - *offset; + pool->frag_offset =3D max_size; + } + + return page; +} + +static inline struct page *page_pool_dev_alloc(struct page_pool *pool, + unsigned int *offset, + unsigned int *size) +{ + gfp_t gfp =3D (GFP_ATOMIC | __GFP_NOWARN); + + return page_pool_alloc(pool, offset, size, gfp); +} + +static inline void *page_pool_cache_alloc(struct page_pool *pool, + unsigned int *size, gfp_t gfp) +{ + unsigned int offset; + struct page *page; + + page =3D page_pool_alloc(pool, &offset, size, gfp); + if (unlikely(!page)) + return NULL; + + return page_address(page) + offset; +} + +static inline void *page_pool_dev_cache_alloc(struct page_pool *pool, + unsigned int *size) +{ + gfp_t gfp =3D (GFP_ATOMIC | __GFP_NOWARN); + + return page_pool_cache_alloc(pool, size, gfp); +} + /** * page_pool_get_dma_dir() - Retrieve the stored DMA direction. * @pool: pool from which page was allocated @@ -222,6 +281,12 @@ static inline void page_pool_recycle_direct(struct pag= e_pool *pool, #define PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA \ (sizeof(dma_addr_t) > sizeof(unsigned long)) =20 +static inline void page_pool_cache_free(struct page_pool *pool, void *data, + bool allow_direct) +{ + page_pool_put_page(pool, virt_to_head_page(data), -1, allow_direct); +} + /** * page_pool_get_dma_addr() - Retrieve the stored DMA address. * @page: page allocated from a page pool diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 1927b9c36c23..74106f6d8f73 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -809,7 +809,7 @@ static void page_pool_empty_ring(struct page_pool *pool) } } =20 -static void page_pool_free(struct page_pool *pool) +static void __page_pool_destroy(struct page_pool *pool) { if (pool->disconnect) pool->disconnect(pool); @@ -860,7 +860,7 @@ static int page_pool_release(struct page_pool *pool) page_pool_scrub(pool); inflight =3D page_pool_inflight(pool); if (!inflight) - page_pool_free(pool); + __page_pool_destroy(pool); =20 return inflight; } --=20 2.33.0 From nobody Fri Sep 20 09:53:58 2024 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 6618CCA0ECE for ; Tue, 12 Sep 2023 08:35:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232804AbjILIfH (ORCPT ); Tue, 12 Sep 2023 04:35:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232740AbjILIe7 (ORCPT ); Tue, 12 Sep 2023 04:34:59 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1BCC010D7; Tue, 12 Sep 2023 01:34:52 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4RlGyN0vstzMlJy; Tue, 12 Sep 2023 16:31:24 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:50 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Jesper Dangaard Brouer , Ilias Apalodimas , Eric Dumazet , Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , John Fastabend , , Subject: [PATCH net-next v8 5/6] page_pool: update document about frag API Date: Tue, 12 Sep 2023 16:31:24 +0800 Message-ID: <20230912083126.65484-6-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" As more drivers begin to use the frag API, update the document about how to decide which API to use for the driver author. Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin --- Documentation/networking/page_pool.rst | 4 +- include/net/page_pool/helpers.h | 88 ++++++++++++++++++++++---- 2 files changed, 79 insertions(+), 13 deletions(-) diff --git a/Documentation/networking/page_pool.rst b/Documentation/network= ing/page_pool.rst index 215ebc92752c..0c0705994f51 100644 --- a/Documentation/networking/page_pool.rst +++ b/Documentation/networking/page_pool.rst @@ -58,7 +58,9 @@ a page will cause no race conditions is enough. =20 .. kernel-doc:: include/net/page_pool/helpers.h :identifiers: page_pool_put_page page_pool_put_full_page - page_pool_recycle_direct page_pool_dev_alloc_pages + page_pool_recycle_direct page_pool_cache_free + page_pool_dev_alloc_pages page_pool_dev_alloc_frag + page_pool_dev_alloc page_pool_dev_cache_alloc page_pool_get_dma_addr page_pool_get_dma_dir =20 .. kernel-doc:: net/core/page_pool.c diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helper= s.h index c0e6c7d1b219..b20afe22c17d 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -8,23 +8,47 @@ /** * DOC: page_pool allocator * - * The page_pool allocator is optimized for the XDP mode that - * uses one frame per-page, but it can fallback on the - * regular page allocator APIs. + * The page_pool allocator is optimized for recycling page or page frag us= ed by + * skb packet and xdp frame. * - * Basic use involves replacing alloc_pages() calls with the - * page_pool_alloc_pages() call. Drivers should use - * page_pool_dev_alloc_pages() replacing dev_alloc_pages(). + * Basic use involves replacing napi_alloc_frag() and alloc_pages() calls = with + * page_pool_cache_alloc() and page_pool_alloc(), which allocate memory wi= th or + * without page splitting depending on the requested memory size. * - * API keeps track of in-flight pages, in order to let API user know - * when it is safe to free a page_pool object. Thus, API users - * must call page_pool_put_page() to free the page, or attach - * the page to a page_pool-aware objects like skbs marked with + * If the driver knows that it always requires full pages or its allocatio= ns are + * always smaller than half a page, it can use one of the more specific API + * calls: + * + * 1. page_pool_alloc_pages(): allocate memory without page splitting when + * driver knows that the memory it need is always bigger than half of the = page + * allocated from page pool. There is no cache line dirtying for 'struct p= age' + * when a page is recycled back to the page pool. + * + * 2. page_pool_alloc_frag(): allocate memory with page splitting when dri= ver + * knows that the memory it need is always smaller than or equal to half o= f the + * page allocated from page pool. Page splitting enables memory saving and= thus + * avoids TLB/cache miss for data access, but there also is some cost to + * implement page splitting, mainly some cache line dirtying/bouncing for + * 'struct page' and atomic operation for page->pp_frag_count. + * + * API keeps track of in-flight pages, in order to let API user know when = it is + * safe to free a page_pool object, the API users must call page_pool_put_= page() + * or page_pool_cache_free() to free the pp page or the pp buffer, or atta= ch the + * pp page or the pp buffer to a page_pool-aware objects like skbs marked = with * skb_mark_for_recycle(). * - * API user must call page_pool_put_page() once on a page, as it - * will either recycle the page, or in case of refcnt > 1, it will + * page_pool_put_page() may be called multi times on the same page if a pa= ge is + * split into multi frags. For the last frag, see page_pool_is_last_frag()= , it + * will either recycle the page, or in case of page->_refcount > 1, it will * release the DMA mapping and in-flight state accounting. + * + * dma_sync_single_range_for_device() is only called for the last pp page = user + * when page_pool is created with PP_FLAG_DMA_SYNC_DEV flag, so it depend = on the + * last freed frag to do the sync_for_device operation for all frags in th= e same + * page when a page is split, the API user must setup pool->p.max_len and + * pool->p.offset correctly and ensure that page_pool_put_page() is called= with + * dma_sync_size being -1 for page_pool_alloc(), page_pool_cache_alloc() a= nd + * page_pool_alloc_frag() API. */ #ifndef _NET_PAGE_POOL_HELPERS_H #define _NET_PAGE_POOL_HELPERS_H @@ -73,6 +97,17 @@ static inline struct page *page_pool_dev_alloc_pages(str= uct page_pool *pool) return page_pool_alloc_pages(pool, gfp); } =20 +/** + * page_pool_dev_alloc_frag() - allocate a page frag. + * @pool: pool from which to allocate + * @offset: offset to the allocated page + * @size: requested size + * + * Get a page frag from the page allocator or page_pool caches. + * + * Return: + * Returns allocated page frag, otherwise return NULL. + */ static inline struct page *page_pool_dev_alloc_frag(struct page_pool *pool, unsigned int *offset, unsigned int size) @@ -111,6 +146,17 @@ static inline struct page *page_pool_alloc(struct page= _pool *pool, return page; } =20 +/** + * page_pool_dev_alloc() - allocate a page or a page frag. + * @pool: pool from which to allocate + * @offset: offset to the allocated page + * @size: in as the requested size, out as the allocated size + * + * Get a page or a page frag from the page allocator or page_pool caches. + * + * Return: + * Returns a page or a page frag, otherwise return NULL. + */ static inline struct page *page_pool_dev_alloc(struct page_pool *pool, unsigned int *offset, unsigned int *size) @@ -133,6 +179,16 @@ static inline void *page_pool_cache_alloc(struct page_= pool *pool, return page_address(page) + offset; } =20 +/** + * page_pool_dev_cache_alloc() - allocate a cache. + * @pool: pool from which to allocate + * @size: in as the requested size, out as the allocated size + * + * Get a cache from the page allocator or page_pool caches. + * + * Return: + * Returns the addr for the allocated cache, otherwise return NULL. + */ static inline void *page_pool_dev_cache_alloc(struct page_pool *pool, unsigned int *size) { @@ -281,6 +337,14 @@ static inline void page_pool_recycle_direct(struct pag= e_pool *pool, #define PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA \ (sizeof(dma_addr_t) > sizeof(unsigned long)) =20 +/** + * page_pool_cache_free() - free a cache into the page_pool + * @pool: pool from which cache was allocated + * @data: addr of cache to be free + * @allow_direct: freed by the consumer, allow lockless caching + * + * Free a cache allocated from page_pool_dev_cache_alloc(). + */ static inline void page_pool_cache_free(struct page_pool *pool, void *data, bool allow_direct) { --=20 2.33.0 From nobody Fri Sep 20 09:53:58 2024 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 26707CA0ECE for ; Tue, 12 Sep 2023 08:35:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232882AbjILIfM (ORCPT ); Tue, 12 Sep 2023 04:35:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232808AbjILIfA (ORCPT ); Tue, 12 Sep 2023 04:35:00 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28B9310DD; Tue, 12 Sep 2023 01:34:54 -0700 (PDT) Received: from dggpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RlGzB35YfzVkfZ; Tue, 12 Sep 2023 16:32:06 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpemm500005.china.huawei.com (7.185.36.74) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 12 Sep 2023 16:34:52 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Lorenzo Bianconi , Alexander Duyck , Liang Chen , Alexander Lobakin , Eric Dumazet , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Subject: [PATCH net-next v8 6/6] net: veth: use newly added page pool API for veth with xdp Date: Tue, 12 Sep 2023 16:31:25 +0800 Message-ID: <20230912083126.65484-7-linyunsheng@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230912083126.65484-1-linyunsheng@huawei.com> References: <20230912083126.65484-1-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500005.china.huawei.com (7.185.36.74) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Use page_pool[_cache]_alloc() API to allocate memory with least memory utilization and performance penalty. Signed-off-by: Yunsheng Lin CC: Lorenzo Bianconi CC: Alexander Duyck CC: Liang Chen CC: Alexander Lobakin --- drivers/net/veth.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 9c6f4f83f22b..a31a792aa00d 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -737,10 +737,11 @@ static int veth_convert_skb_to_xdp_buff(struct veth_r= q *rq, if (skb_shared(skb) || skb_head_is_locked(skb) || skb_shinfo(skb)->nr_frags || skb_headroom(skb) < XDP_PACKET_HEADROOM) { - u32 size, len, max_head_size, off; + u32 size, len, max_head_size, off, truesize, page_offset; struct sk_buff *nskb; struct page *page; int i, head_off; + void *data; =20 /* We need a private copy of the skb and data buffers since * the ebpf program can modify it. We segment the original skb @@ -753,14 +754,17 @@ static int veth_convert_skb_to_xdp_buff(struct veth_r= q *rq, if (skb->len > PAGE_SIZE * MAX_SKB_FRAGS + max_head_size) goto drop; =20 + size =3D min_t(u32, skb->len, max_head_size); + truesize =3D SKB_HEAD_ALIGN(size) + VETH_XDP_HEADROOM; + /* Allocate skb head */ - page =3D page_pool_dev_alloc_pages(rq->page_pool); - if (!page) + data =3D page_pool_dev_cache_alloc(rq->page_pool, &truesize); + if (!data) goto drop; =20 - nskb =3D napi_build_skb(page_address(page), PAGE_SIZE); + nskb =3D napi_build_skb(data, truesize); if (!nskb) { - page_pool_put_full_page(rq->page_pool, page, true); + page_pool_cache_free(rq->page_pool, data, true); goto drop; } =20 @@ -768,7 +772,6 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq = *rq, skb_copy_header(nskb, skb); skb_mark_for_recycle(nskb); =20 - size =3D min_t(u32, skb->len, max_head_size); if (skb_copy_bits(skb, 0, nskb->data, size)) { consume_skb(nskb); goto drop; @@ -783,14 +786,18 @@ static int veth_convert_skb_to_xdp_buff(struct veth_r= q *rq, len =3D skb->len - off; =20 for (i =3D 0; i < MAX_SKB_FRAGS && off < skb->len; i++) { - page =3D page_pool_dev_alloc_pages(rq->page_pool); + size =3D min_t(u32, len, PAGE_SIZE); + truesize =3D size; + + page =3D page_pool_dev_alloc(rq->page_pool, &page_offset, + &truesize); if (!page) { consume_skb(nskb); goto drop; } =20 - size =3D min_t(u32, len, PAGE_SIZE); - skb_add_rx_frag(nskb, i, page, 0, size, PAGE_SIZE); + skb_add_rx_frag(nskb, i, page, page_offset, size, + truesize); if (skb_copy_bits(skb, off, page_address(page), size)) { consume_skb(nskb); --=20 2.33.0