From patchwork Wed Mar 24 21:34:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 12162463 X-Patchwork-Delegate: kuba@kernel.org 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 B41FAC433E4 for ; Wed, 24 Mar 2021 21:35:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91AE961A1E for ; Wed, 24 Mar 2021 21:35:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234294AbhCXVf1 (ORCPT ); Wed, 24 Mar 2021 17:35:27 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:52936 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233901AbhCXVe6 (ORCPT ); Wed, 24 Mar 2021 17:34:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616621697; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UfGrVeHEI0sce0qvVh5BuQBoPgz+S960/h6BqEQEhUA=; b=ERRuAvWGOk6kXTebuYVxuL3GFM5ehcFn75ujfGQJeM8lhg2Q/I7azmcpLb+dpquTzbZeUH J6bGz9Lq2fEUIHr8MpKCpmffwT5kbjtwfJ9Qn3W++jp0yEJukZ87NMYhhbXb+hQ8LST8pI 0iTAlE3a5Gx2pzARdJ8+emv4zM1GrS4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-339-SdPLb4OhPCStBnI5K1dcdA-1; Wed, 24 Mar 2021 17:34:55 -0400 X-MC-Unique: SdPLb4OhPCStBnI5K1dcdA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4FC30185302D; Wed, 24 Mar 2021 21:34:53 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.40.208.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id 452EB6A8F1; Wed, 24 Mar 2021 21:34:50 +0000 (UTC) Received: from [10.1.1.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 2CC8E300A2A79; Wed, 24 Mar 2021 22:34:49 +0100 (CET) Subject: [PATCH mel-git 1/3] net: page_pool: refactor dma_map into own function page_pool_dma_map From: Jesper Dangaard Brouer To: Mel Gorman , linux-mm@kvack.org Cc: Jesper Dangaard Brouer , chuck.lever@oracle.com, Alexander Duyck , netdev@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 24 Mar 2021 22:34:49 +0100 Message-ID: <161662168912.940814.14561278459325120343.stgit@firesoul> In-Reply-To: <161662166301.940814.9765023867613542235.stgit@firesoul> References: <161662166301.940814.9765023867613542235.stgit@firesoul> User-Agent: StGit/0.19 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org In preparation for next patch, move the dma mapping into its own function, as this will make it easier to follow the changes. V2: make page_pool_dma_map return boolean (Ilias) Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Mel Gorman Reviewed-by: Ilias Apalodimas --- net/core/page_pool.c | 45 ++++++++++++++++++++++++++------------------- 1 file changed, 26 insertions(+), 19 deletions(-) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index ad8b0707af04..40e1b2beaa6c 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -180,14 +180,37 @@ static void page_pool_dma_sync_for_device(struct page_pool *pool, pool->p.dma_dir); } +static bool page_pool_dma_map(struct page_pool *pool, struct page *page) +{ + dma_addr_t dma; + + /* Setup DMA mapping: use 'struct page' area for storing DMA-addr + * since dma_addr_t can be either 32 or 64 bits and does not always fit + * into page private data (i.e 32bit cpu with 64bit DMA caps) + * This mapping is kept for lifetime of page, until leaving pool. + */ + dma = dma_map_page_attrs(pool->p.dev, page, 0, + (PAGE_SIZE << pool->p.order), + pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC); + if (dma_mapping_error(pool->p.dev, dma)) + return false; + + page->dma_addr = dma; + + if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) + page_pool_dma_sync_for_device(pool, page, pool->p.max_len); + + return true; +} + /* slow path */ noinline static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, gfp_t _gfp) { + unsigned int pp_flags = pool->p.flags; struct page *page; gfp_t gfp = _gfp; - dma_addr_t dma; /* We could always set __GFP_COMP, and avoid this branch, as * prep_new_page() can handle order-0 with __GFP_COMP. @@ -211,30 +234,14 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, if (!page) return NULL; - if (!(pool->p.flags & PP_FLAG_DMA_MAP)) - goto skip_dma_map; - - /* Setup DMA mapping: use 'struct page' area for storing DMA-addr - * since dma_addr_t can be either 32 or 64 bits and does not always fit - * into page private data (i.e 32bit cpu with 64bit DMA caps) - * This mapping is kept for lifetime of page, until leaving pool. - */ - dma = dma_map_page_attrs(pool->p.dev, page, 0, - (PAGE_SIZE << pool->p.order), - pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC); - if (dma_mapping_error(pool->p.dev, dma)) { + if ((pp_flags & PP_FLAG_DMA_MAP) && + unlikely(!page_pool_dma_map(pool, page))) { put_page(page); return NULL; } - page->dma_addr = dma; - if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) - page_pool_dma_sync_for_device(pool, page, pool->p.max_len); - -skip_dma_map: /* Track how many pages are held 'in-flight' */ pool->pages_state_hold_cnt++; - trace_page_pool_state_hold(pool, page, pool->pages_state_hold_cnt); /* When page just alloc'ed is should/must have refcnt 1. */ From patchwork Wed Mar 24 21:34:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 12162465 X-Patchwork-Delegate: kuba@kernel.org 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=-21.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 29A61C433E5 for ; Wed, 24 Mar 2021 21:35:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC5EC61A2A for ; Wed, 24 Mar 2021 21:35:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238476AbhCXVfc (ORCPT ); Wed, 24 Mar 2021 17:35:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:40385 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234021AbhCXVfF (ORCPT ); Wed, 24 Mar 2021 17:35:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616621704; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xNVBBcPNMnk3z4ciJsLBFU3/kjZdyv/OnoV8PVtQezs=; b=Pu3Ol0vJFfP9icZMFqMot+5NVPvi78Ze2YK+Gw1k4JPfuHa7rma35b79cYSl/Yc1qNJ+HL 61EvOE1iVBrcNY+4NG8RTgJtLrKx23nBv4FWx/CEDLLIfrcr9lI93nomeyF//wQ8t71QER 7yIkCFdq7p0gi4rgBc4Mq9Fzf4Jjs/A= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-378--H7b821KPA-OGqUEpO9hVQ-1; Wed, 24 Mar 2021 17:35:00 -0400 X-MC-Unique: -H7b821KPA-OGqUEpO9hVQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E85431009462; Wed, 24 Mar 2021 21:34:58 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.40.208.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id 435BB6E6F5; Wed, 24 Mar 2021 21:34:55 +0000 (UTC) Received: from [10.1.1.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 3DA90300A2A79; Wed, 24 Mar 2021 22:34:54 +0100 (CET) Subject: [PATCH mel-git 2/3] net: page_pool: use alloc_pages_bulk in refill code path From: Jesper Dangaard Brouer To: Mel Gorman , linux-mm@kvack.org Cc: Jesper Dangaard Brouer , chuck.lever@oracle.com, Alexander Duyck , netdev@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 24 Mar 2021 22:34:54 +0100 Message-ID: <161662169419.940814.17570004014550134474.stgit@firesoul> In-Reply-To: <161662166301.940814.9765023867613542235.stgit@firesoul> References: <161662166301.940814.9765023867613542235.stgit@firesoul> User-Agent: StGit/0.19 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org There are cases where the page_pool need to refill with pages from the page allocator. Some workloads cause the page_pool to release pages instead of recycling these pages. For these workload it can improve performance to bulk alloc pages from the page-allocator to refill the alloc cache. For XDP-redirect workload with 100G mlx5 driver (that use page_pool) redirecting xdp_frame packets into a veth, that does XDP_PASS to create an SKB from the xdp_frame, which then cannot return the page to the page_pool. Performance results under GitHub xdp-project[1]: [1] https://github.com/xdp-project/xdp-project/blob/master/areas/mem/page_pool06_alloc_pages_bulk.org Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Mel Gorman --- net/core/page_pool.c | 72 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 46 insertions(+), 26 deletions(-) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 40e1b2beaa6c..3bf6e7f5fc89 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -203,38 +203,17 @@ static bool page_pool_dma_map(struct page_pool *pool, struct page *page) return true; } -/* slow path */ -noinline -static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, - gfp_t _gfp) +static struct page *__page_pool_alloc_page_order(struct page_pool *pool, + gfp_t gfp) { - unsigned int pp_flags = pool->p.flags; struct page *page; - gfp_t gfp = _gfp; - - /* We could always set __GFP_COMP, and avoid this branch, as - * prep_new_page() can handle order-0 with __GFP_COMP. - */ - if (pool->p.order) - gfp |= __GFP_COMP; - - /* FUTURE development: - * - * Current slow-path essentially falls back to single page - * allocations, which doesn't improve performance. This code - * need bulk allocation support from the page allocator code. - */ - /* Cache was empty, do real allocation */ -#ifdef CONFIG_NUMA + gfp |= __GFP_COMP; page = alloc_pages_node(pool->p.nid, gfp, pool->p.order); -#else - page = alloc_pages(gfp, pool->p.order); -#endif - if (!page) + if (unlikely(!page)) return NULL; - if ((pp_flags & PP_FLAG_DMA_MAP) && + if ((pool->p.flags & PP_FLAG_DMA_MAP) && unlikely(!page_pool_dma_map(pool, page))) { put_page(page); return NULL; @@ -243,6 +222,47 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, /* Track how many pages are held 'in-flight' */ pool->pages_state_hold_cnt++; trace_page_pool_state_hold(pool, page, pool->pages_state_hold_cnt); + return page; +} + +/* slow path */ +noinline +static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, + gfp_t gfp) +{ + const int bulk = PP_ALLOC_CACHE_REFILL; + unsigned int pp_flags = pool->p.flags; + unsigned int pp_order = pool->p.order; + struct page *page, *next; + LIST_HEAD(page_list); + + /* Don't support bulk alloc for high-order pages */ + if (unlikely(pp_order)) + return __page_pool_alloc_page_order(pool, gfp); + + if (unlikely(!alloc_pages_bulk_list(gfp, bulk, &page_list))) + return NULL; + + list_for_each_entry_safe(page, next, &page_list, lru) { + list_del(&page->lru); + if ((pp_flags & PP_FLAG_DMA_MAP) && + unlikely(!page_pool_dma_map(pool, page))) { + put_page(page); + continue; + } + /* Alloc cache have room as it is empty on function call */ + pool->alloc.cache[pool->alloc.count++] = page; + /* Track how many pages are held 'in-flight' */ + pool->pages_state_hold_cnt++; + trace_page_pool_state_hold(pool, page, + pool->pages_state_hold_cnt); + } + + /* Return last page */ + if (likely(pool->alloc.count > 0)) + page = pool->alloc.cache[--pool->alloc.count]; + else + page = NULL; /* When page just alloc'ed is should/must have refcnt 1. */ return page; From patchwork Wed Mar 24 21:34:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 12162467 X-Patchwork-Delegate: kuba@kernel.org 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 307C8C433EA for ; 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Wed, 24 Mar 2021 17:35:05 -0400 X-MC-Unique: u3BcfBy3OJWg78JhInYkYQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 254FF801817; Wed, 24 Mar 2021 21:35:04 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.40.208.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5E1E65D9DE; Wed, 24 Mar 2021 21:35:00 +0000 (UTC) Received: from [10.1.1.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 4E956300A2A79; Wed, 24 Mar 2021 22:34:59 +0100 (CET) Subject: [PATCH mel-git 3/3] net: page_pool: convert to use alloc_pages_bulk_array variant From: Jesper Dangaard Brouer To: Mel Gorman , linux-mm@kvack.org Cc: Jesper Dangaard Brouer , chuck.lever@oracle.com, Alexander Duyck , netdev@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 24 Mar 2021 22:34:59 +0100 Message-ID: <161662169926.940814.10878534922009676003.stgit@firesoul> In-Reply-To: <161662166301.940814.9765023867613542235.stgit@firesoul> References: <161662166301.940814.9765023867613542235.stgit@firesoul> User-Agent: StGit/0.19 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Using the API variant alloc_pages_bulk_array from page_pool was done in a separate patch to ease benchmarking the variants separately. Maintainers can squash patch if preferred. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Mel Gorman --- include/net/page_pool.h | 2 +- net/core/page_pool.c | 22 ++++++++++++++++------ 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/include/net/page_pool.h b/include/net/page_pool.h index b5b195305346..6d517a37c18b 100644 --- a/include/net/page_pool.h +++ b/include/net/page_pool.h @@ -65,7 +65,7 @@ #define PP_ALLOC_CACHE_REFILL 64 struct pp_alloc_cache { u32 count; - void *cache[PP_ALLOC_CACHE_SIZE]; + struct page *cache[PP_ALLOC_CACHE_SIZE]; }; struct page_pool_params { diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 3bf6e7f5fc89..9ec1aa9640ad 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -233,24 +233,34 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, const int bulk = PP_ALLOC_CACHE_REFILL; unsigned int pp_flags = pool->p.flags; unsigned int pp_order = pool->p.order; - struct page *page, *next; - LIST_HEAD(page_list); + struct page *page; + int i, nr_pages; /* Don't support bulk alloc for high-order pages */ if (unlikely(pp_order)) return __page_pool_alloc_page_order(pool, gfp); - if (unlikely(!alloc_pages_bulk_list(gfp, bulk, &page_list))) + /* Unnecessary as alloc cache is empty, but guarantees zero count */ + if (unlikely(pool->alloc.count > 0)) + return pool->alloc.cache[--pool->alloc.count]; + + /* Mark empty alloc.cache slots "empty" for alloc_pages_bulk_array */ + memset(&pool->alloc.cache, 0, sizeof(void *) * bulk); + + nr_pages = alloc_pages_bulk_array(gfp, bulk, pool->alloc.cache); + if (unlikely(!nr_pages)) return NULL; - list_for_each_entry_safe(page, next, &page_list, lru) { - list_del(&page->lru); + /* Pages have been filled into alloc.cache array, but count is zero and + * page element have not been (possibly) DMA mapped. + */ + for (i = 0; i < nr_pages; i++) { + page = pool->alloc.cache[i]; if ((pp_flags & PP_FLAG_DMA_MAP) && unlikely(!page_pool_dma_map(pool, page))) { put_page(page); continue; } - /* Alloc cache have room as it is empty on function call */ pool->alloc.cache[pool->alloc.count++] = page; /* Track how many pages are held 'in-flight' */ pool->pages_state_hold_cnt++;