From nobody Fri Dec 19 08:40:43 2025 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53A751FF5FA; Fri, 6 Dec 2024 12:32:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733488346; cv=none; b=YxyZjH8EcKlIUesj3nfX862hheCZoh4SZ3CKygCOxt/g/aZ6V/dmir3tI0oYUDkMeqQlJcvecbnXeftfTeESpxKZuFpNFbsaNrv+qYa8MNv5Wwm8QdoaHk39HyyBHX4NmddSCWQlJaFCTO2qTMubRGFeeAIGPvZGfJGjXNdKEhI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733488346; c=relaxed/simple; bh=u7Y8vcACw0nN7XvzUTUQjb+zsdFCruoZHnJv/2+6AWE=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=QIdK9ew9P96ji2V0HIkzDmVSKwFTummUfSzcm4PeOJAKj/jhAcow78Whm4Rde79A0LFUy/Q+IBHRh/0NFBZruf/Bz/ox5vpQNDLjbuYVfyqPMAD20gDQjqB5Vh7PB28L4rkzw7v/DljsOh0mSBGJ1IBiYMUaS/AYlAYqqIGjvtE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.162.112]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Y4VvZ743kz1kvGW; Fri, 6 Dec 2024 20:30:02 +0800 (CST) Received: from dggpemf200006.china.huawei.com (unknown [7.185.36.61]) by mail.maildlp.com (Postfix) with ESMTPS id 507741401DC; Fri, 6 Dec 2024 20:32:22 +0800 (CST) Received: from localhost.localdomain (10.90.30.45) by dggpemf200006.china.huawei.com (7.185.36.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 6 Dec 2024 20:32:22 +0800 From: Yunsheng Lin To: , , CC: , , Yunsheng Lin , Alexander Duyck , Andrew Morton , Linux-MM Subject: [PATCH net-next v2 01/10] mm: page_frag: some minor refactoring before adding new API Date: Fri, 6 Dec 2024 20:25:24 +0800 Message-ID: <20241206122533.3589947-2-linyunsheng@huawei.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20241206122533.3589947-1-linyunsheng@huawei.com> References: <20241206122533.3589947-1-linyunsheng@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemf200006.china.huawei.com (7.185.36.61) Content-Type: text/plain; charset="utf-8" Refactor common codes from __page_frag_alloc_va_align() to __page_frag_cache_prepare() and __page_frag_cache_commit(), so that the new API can make use of them. CC: Alexander Duyck CC: Andrew Morton CC: Linux-MM Signed-off-by: Yunsheng Lin --- include/linux/page_frag_cache.h | 34 ++++++++++++++++++++++++++-- mm/page_frag_cache.c | 40 ++++++++++++++++++++++++++------- 2 files changed, 64 insertions(+), 10 deletions(-) diff --git a/include/linux/page_frag_cache.h b/include/linux/page_frag_cach= e.h index 41a91df82631..5ae97f93a0a1 100644 --- a/include/linux/page_frag_cache.h +++ b/include/linux/page_frag_cache.h @@ -5,6 +5,7 @@ =20 #include #include +#include #include #include =20 @@ -39,8 +40,37 @@ static inline bool page_frag_cache_is_pfmemalloc(struct = page_frag_cache *nc) =20 void page_frag_cache_drain(struct page_frag_cache *nc); void __page_frag_cache_drain(struct page *page, unsigned int count); -void *__page_frag_alloc_align(struct page_frag_cache *nc, unsigned int fra= gsz, - gfp_t gfp_mask, unsigned int align_mask); +void *__page_frag_cache_prepare(struct page_frag_cache *nc, unsigned int f= ragsz, + struct page_frag *pfrag, gfp_t gfp_mask, + unsigned int align_mask); +unsigned int __page_frag_cache_commit_noref(struct page_frag_cache *nc, + struct page_frag *pfrag, + unsigned int used_sz); + +static inline unsigned int __page_frag_cache_commit(struct page_frag_cache= *nc, + struct page_frag *pfrag, + unsigned int used_sz) +{ + VM_BUG_ON(!nc->pagecnt_bias); + nc->pagecnt_bias--; + + return __page_frag_cache_commit_noref(nc, pfrag, used_sz); +} + +static inline void *__page_frag_alloc_align(struct page_frag_cache *nc, + unsigned int fragsz, gfp_t gfp_mask, + unsigned int align_mask) +{ + struct page_frag page_frag; + void *va; + + va =3D __page_frag_cache_prepare(nc, fragsz, &page_frag, gfp_mask, + align_mask); + if (likely(va)) + __page_frag_cache_commit(nc, &page_frag, fragsz); + + return va; +} =20 static inline void *page_frag_alloc_align(struct page_frag_cache *nc, unsigned int fragsz, gfp_t gfp_mask, diff --git a/mm/page_frag_cache.c b/mm/page_frag_cache.c index 3f7a203d35c6..f55d34cf7d43 100644 --- a/mm/page_frag_cache.c +++ b/mm/page_frag_cache.c @@ -90,9 +90,31 @@ void __page_frag_cache_drain(struct page *page, unsigned= int count) } EXPORT_SYMBOL(__page_frag_cache_drain); =20 -void *__page_frag_alloc_align(struct page_frag_cache *nc, - unsigned int fragsz, gfp_t gfp_mask, - unsigned int align_mask) +unsigned int __page_frag_cache_commit_noref(struct page_frag_cache *nc, + struct page_frag *pfrag, + unsigned int used_sz) +{ + unsigned int orig_offset; + + VM_BUG_ON(used_sz > pfrag->size); + VM_BUG_ON(pfrag->page !=3D encoded_page_decode_page(nc->encoded_page)); + VM_BUG_ON(pfrag->offset + pfrag->size > + (PAGE_SIZE << encoded_page_decode_order(nc->encoded_page))); + + /* pfrag->offset might be bigger than the nc->offset due to alignment */ + VM_BUG_ON(nc->offset > pfrag->offset); + + orig_offset =3D nc->offset; + nc->offset =3D pfrag->offset + used_sz; + + /* Return true size back to caller considering the offset alignment */ + return nc->offset - orig_offset; +} +EXPORT_SYMBOL(__page_frag_cache_commit_noref); + +void *__page_frag_cache_prepare(struct page_frag_cache *nc, unsigned int f= ragsz, + struct page_frag *pfrag, gfp_t gfp_mask, + unsigned int align_mask) { unsigned long encoded_page =3D nc->encoded_page; unsigned int size, offset; @@ -114,6 +136,8 @@ void *__page_frag_alloc_align(struct page_frag_cache *n= c, /* reset page count bias and offset to start of new frag */ nc->pagecnt_bias =3D PAGE_FRAG_CACHE_MAX_SIZE + 1; nc->offset =3D 0; + } else { + page =3D encoded_page_decode_page(encoded_page); } =20 size =3D PAGE_SIZE << encoded_page_decode_order(encoded_page); @@ -132,8 +156,6 @@ void *__page_frag_alloc_align(struct page_frag_cache *n= c, return NULL; } =20 - page =3D encoded_page_decode_page(encoded_page); - if (!page_ref_sub_and_test(page, nc->pagecnt_bias)) goto refill; =20 @@ -148,15 +170,17 @@ void *__page_frag_alloc_align(struct page_frag_cache = *nc, =20 /* reset page count bias and offset to start of new frag */ nc->pagecnt_bias =3D PAGE_FRAG_CACHE_MAX_SIZE + 1; + nc->offset =3D 0; offset =3D 0; } =20 - nc->pagecnt_bias--; - nc->offset =3D offset + fragsz; + pfrag->page =3D page; + pfrag->offset =3D offset; + pfrag->size =3D size - offset; =20 return encoded_page_decode_virt(encoded_page) + offset; } -EXPORT_SYMBOL(__page_frag_alloc_align); +EXPORT_SYMBOL(__page_frag_cache_prepare); =20 /* * Frees a page fragment allocated out of either a compound or order 0 pag= e. --=20 2.33.0