From patchwork Mon Nov 6 02:44:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13446234 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 62692C001DD for ; Mon, 6 Nov 2023 02:44:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230367AbjKFCo5 (ORCPT ); Sun, 5 Nov 2023 21:44:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230305AbjKFCoy (ORCPT ); Sun, 5 Nov 2023 21:44:54 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91526D67 for ; Sun, 5 Nov 2023 18:44:34 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-da0c4ab85e2so2276409276.2 for ; Sun, 05 Nov 2023 18:44:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1699238673; x=1699843473; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=NQu48K4LNQ8WFJH6/Q5I7aNtbI5kIYTQfwkiquHqTME=; b=N5RhBrIqL6fIiMOsYG8SLCQWLyW4c0MlgoRmV8kWl/TlVyQadZXrEIdXt2DxU+M47Y 76dp3mFzyiAE/FTCdMcup+83CQOgNE8i44gvvr1W0YJG8NkOUQMDsMRxunjeewFr/8e3 JAahbR8rhWaykQEJLAHjzvxUAJ4pkZo+HPwjlMYz/+ixIU1UMQe2I/7Gfn+Q/BJjo7KZ +5lqMiL925kkqlXs2VwoAyLlOYjjy+MZg2UOlZeg9XGYjeFI8C0QjqF9DZ3eTAHpopb0 1bctWyNN21f05DffBSO2iY3a4JE+ZwPzvwLzt8Eqbylrxwf7ZGBtlwidyhLJXgFiY6Jl UxLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699238673; x=1699843473; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=NQu48K4LNQ8WFJH6/Q5I7aNtbI5kIYTQfwkiquHqTME=; b=KU/1dR656dFDP8pncK/JNt/DtKeVHtaTexLixMAm5Uk9F9sFnzFOSfVdgZNQpongFO YZlJmV6UM8NDLUrpyCd6HQ2OwYlJ1mWs+jbgvG4YRG/7MGw1Mw71MdgSpKchLYpKACQC yQHdzssrg1TOOhOwcEsxmqhUPKDAU4dM0tW7lJ+k4cUl1017p5608RKhKyF0pU/9nDKc zNClvjpCQVFOL+hbBbrswnRoIBNf32cIL7KPdbX8e+PrVNf47dO+e9HUGJ3NbefGdO81 nS3vDHUcE8dRpa6k1rCdDkQR7Iv2kyeMp/aBlkQI6gvYzZkOAkpx/5X0VbCALtWLGV1N Xs0g== X-Gm-Message-State: AOJu0YyO+c6SRjpC3p3QyDvh+N0Y7ZGUAHEILe42zGRhsA1KqZqQQC4v T0WfXKONc2tKa5p8iBmtrYtFuhhcyxZLMvF03A== X-Google-Smtp-Source: AGHT+IEZMbWQfzrxoPZHwOWR4BvATqps1Lm805Xf6dRuk23Kr0wtrH56ZlHocpW6kuXWCf2FI0sYhcvf7cTOroJczw== X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:35de:fff:97b7:db3e]) (user=almasrymina job=sendgmr) by 2002:a25:d785:0:b0:da0:5af7:d51a with SMTP id o127-20020a25d785000000b00da05af7d51amr582834ybg.0.1699238673723; Sun, 05 Nov 2023 18:44:33 -0800 (PST) Date: Sun, 5 Nov 2023 18:44:06 -0800 In-Reply-To: <20231106024413.2801438-1-almasrymina@google.com> Mime-Version: 1.0 References: <20231106024413.2801438-1-almasrymina@google.com> X-Mailer: git-send-email 2.42.0.869.gea05f2083d-goog Message-ID: <20231106024413.2801438-8-almasrymina@google.com> Subject: [RFC PATCH v3 07/12] page-pool: device memory support From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jesper Dangaard Brouer , Ilias Apalodimas , Arnd Bergmann , David Ahern , Willem de Bruijn , Shuah Khan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Shakeel Butt , Jeroen de Borst , Praveen Kaligineedi Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Overload the LSB of struct page* to indicate that it's a page_pool_iov. Refactor mm calls on struct page* into helpers, and add page_pool_iov handling on those helpers. Modify callers of these mm APIs with calls to these helpers instead. In areas where struct page* is dereferenced, add a check for special handling of page_pool_iov. Signed-off-by: Mina Almasry --- include/net/page_pool/helpers.h | 74 ++++++++++++++++++++++++++++++++- net/core/page_pool.c | 63 ++++++++++++++++++++-------- 2 files changed, 118 insertions(+), 19 deletions(-) diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h index b93243c2a640..08f1a2cc70d2 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -151,6 +151,64 @@ static inline struct page_pool_iov *page_to_page_pool_iov(struct page *page) return NULL; } +static inline int page_pool_page_ref_count(struct page *page) +{ + if (page_is_page_pool_iov(page)) + return page_pool_iov_refcount(page_to_page_pool_iov(page)); + + return page_ref_count(page); +} + +static inline void page_pool_page_get_many(struct page *page, + unsigned int count) +{ + if (page_is_page_pool_iov(page)) + return page_pool_iov_get_many(page_to_page_pool_iov(page), + count); + + return page_ref_add(page, count); +} + +static inline void page_pool_page_put_many(struct page *page, + unsigned int count) +{ + if (page_is_page_pool_iov(page)) + return page_pool_iov_put_many(page_to_page_pool_iov(page), + count); + + if (count > 1) + page_ref_sub(page, count - 1); + + put_page(page); +} + +static inline bool page_pool_page_is_pfmemalloc(struct page *page) +{ + if (page_is_page_pool_iov(page)) + return false; + + return page_is_pfmemalloc(page); +} + +static inline bool page_pool_page_is_pref_nid(struct page *page, int pref_nid) +{ + /* Assume page_pool_iov are on the preferred node without actually + * checking... + * + * This check is only used to check for recycling memory in the page + * pool's fast paths. Currently the only implementation of page_pool_iov + * is dmabuf device memory. It's a deliberate decision by the user to + * bind a certain dmabuf to a certain netdev, and the netdev rx queue + * would not be able to reallocate memory from another dmabuf that + * exists on the preferred node, so, this check doesn't make much sense + * in this case. Assume all page_pool_iovs can be recycled for now. + */ + if (page_is_page_pool_iov(page)) + return true; + + return page_to_nid(page) == pref_nid; +} + /** * page_pool_dev_alloc_pages() - allocate a page. * @pool: pool from which to allocate @@ -301,6 +359,9 @@ static inline long page_pool_defrag_page(struct page *page, long nr) { long ret; + if (page_is_page_pool_iov(page)) + return -EINVAL; + /* If nr == pp_frag_count then we have cleared all remaining * references to the page: * 1. 'n == 1': no need to actually overwrite it. @@ -431,7 +492,12 @@ static inline void page_pool_free_va(struct page_pool *pool, void *va, */ static inline dma_addr_t page_pool_get_dma_addr(struct page *page) { - dma_addr_t ret = page->dma_addr; + dma_addr_t ret; + + if (page_is_page_pool_iov(page)) + return page_pool_iov_dma_addr(page_to_page_pool_iov(page)); + + ret = page->dma_addr; if (PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA) ret <<= PAGE_SHIFT; @@ -441,6 +507,12 @@ static inline dma_addr_t page_pool_get_dma_addr(struct page *page) static inline bool page_pool_set_dma_addr(struct page *page, dma_addr_t addr) { + /* page_pool_iovs are mapped and their dma-addr can't be modified. */ + if (page_is_page_pool_iov(page)) { + DEBUG_NET_WARN_ON_ONCE(true); + return false; + } + if (PAGE_POOL_32BIT_ARCH_WITH_64BIT_DMA) { page->dma_addr = addr >> PAGE_SHIFT; diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 138ddea0b28f..d211996d423b 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -317,7 +317,7 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool) if (unlikely(!page)) break; - if (likely(page_to_nid(page) == pref_nid)) { + if (likely(page_pool_page_is_pref_nid(page, pref_nid))) { pool->alloc.cache[pool->alloc.count++] = page; } else { /* NUMA mismatch; @@ -362,7 +362,15 @@ static void page_pool_dma_sync_for_device(struct page_pool *pool, struct page *page, unsigned int dma_sync_size) { - dma_addr_t dma_addr = page_pool_get_dma_addr(page); + dma_addr_t dma_addr; + + /* page_pool_iov memory provider do not support PP_FLAG_DMA_SYNC_DEV */ + if (page_is_page_pool_iov(page)) { + DEBUG_NET_WARN_ON_ONCE(true); + return; + } + + dma_addr = page_pool_get_dma_addr(page); dma_sync_size = min(dma_sync_size, pool->p.max_len); dma_sync_single_range_for_device(pool->p.dev, dma_addr, @@ -374,6 +382,12 @@ static bool page_pool_dma_map(struct page_pool *pool, struct page *page) { dma_addr_t dma; + if (page_is_page_pool_iov(page)) { + /* page_pool_iovs are already mapped */ + DEBUG_NET_WARN_ON_ONCE(true); + return true; + } + /* 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) @@ -405,22 +419,33 @@ static bool page_pool_dma_map(struct page_pool *pool, struct page *page) static void page_pool_set_pp_info(struct page_pool *pool, struct page *page) { - page->pp = pool; - page->pp_magic |= PP_SIGNATURE; - - /* Ensuring all pages have been split into one fragment 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 (!page_is_page_pool_iov(page)) { + page->pp = pool; + page->pp_magic |= PP_SIGNATURE; + + /* Ensuring all pages have been split into one fragment + * 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); + } else { + page_to_page_pool_iov(page)->pp = pool; + } + if (pool->p.init_callback) pool->p.init_callback(page, pool->p.init_arg); } static void page_pool_clear_pp_info(struct page *page) { + if (page_is_page_pool_iov(page)) { + page_to_page_pool_iov(page)->pp = NULL; + return; + } + page->pp_magic = 0; page->pp = NULL; } @@ -630,7 +655,7 @@ static bool page_pool_recycle_in_cache(struct page *page, return false; } - /* Caller MUST have verified/know (page_ref_count(page) == 1) */ + /* Caller MUST have verified/know (page_pool_page_ref_count(page) == 1) */ pool->alloc.cache[pool->alloc.count++] = page; recycle_stat_inc(pool, cached); return true; @@ -655,9 +680,10 @@ __page_pool_put_page(struct page_pool *pool, struct page *page, * refcnt == 1 means page_pool owns page, and can recycle it. * * page is NOT reusable when allocated when system is under - * some pressure. (page_is_pfmemalloc) + * some pressure. (page_pool_page_is_pfmemalloc) */ - if (likely(page_ref_count(page) == 1 && !page_is_pfmemalloc(page))) { + if (likely(page_pool_page_ref_count(page) == 1 && + !page_pool_page_is_pfmemalloc(page))) { /* Read barrier done in page_ref_count / READ_ONCE */ if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) @@ -772,7 +798,8 @@ static struct page *page_pool_drain_frag(struct page_pool *pool, if (likely(page_pool_defrag_page(page, drain_count))) return NULL; - if (page_ref_count(page) == 1 && !page_is_pfmemalloc(page)) { + if (page_pool_page_ref_count(page) == 1 && + !page_pool_page_is_pfmemalloc(page)) { if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) page_pool_dma_sync_for_device(pool, page, -1); @@ -848,9 +875,9 @@ static void page_pool_empty_ring(struct page_pool *pool) /* Empty recycle ring */ while ((page = ptr_ring_consume_bh(&pool->ring))) { /* Verify the refcnt invariant of cached pages */ - if (!(page_ref_count(page) == 1)) + if (!(page_pool_page_ref_count(page) == 1)) pr_crit("%s() page_pool refcnt %d violation\n", - __func__, page_ref_count(page)); + __func__, page_pool_page_ref_count(page)); page_pool_return_page(pool, page); }