From b29e64d8798018c3e82a426ec34b39b825ac68dc Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Thu, 26 Jul 2018 20:21:59 +0800 Subject: [PATCH] staging: erofs: add erofs_allocpage This patch introduces an temporary _on-stack_ page pool to reuse the freed page directly as much as it can for better performance and release all pages at a time, it also slightly reduces the possibility of the potential memory allocation failure. Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman --- drivers/staging/erofs/Makefile | 2 +- drivers/staging/erofs/internal.h | 7 +++++++ drivers/staging/erofs/utils.c | 31 +++++++++++++++++++++++++++++++ 3 files changed, 39 insertions(+), 1 deletion(-) create mode 100644 drivers/staging/erofs/utils.c diff --git a/drivers/staging/erofs/Makefile b/drivers/staging/erofs/Makefile index 8558c76..490fa6c 100644 --- a/drivers/staging/erofs/Makefile +++ b/drivers/staging/erofs/Makefile @@ -7,7 +7,7 @@ ccflags-y += -Wall -DEROFS_VERSION=\"$(EROFS_VERSION)\" obj-$(CONFIG_EROFS_FS) += erofs.o # staging requirement: to be self-contained in its own directory ccflags-y += -I$(src)/include -erofs-objs := super.o inode.o data.o namei.o dir.o +erofs-objs := super.o inode.o data.o namei.o dir.o utils.o erofs-$(CONFIG_EROFS_FS_XATTR) += xattr.o erofs-$(CONFIG_EROFS_FS_ZIP) += unzip_vle.o diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h index bea5ec4..210ab6c 100644 --- a/drivers/staging/erofs/internal.h +++ b/drivers/staging/erofs/internal.h @@ -369,5 +369,12 @@ static inline void erofs_vunmap(const void *mem, unsigned int count) #endif } +/* utils.c */ +extern struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp); + +#ifndef lru_to_page +#define lru_to_page(head) (list_entry((head)->prev, struct page, lru)) +#endif + #endif diff --git a/drivers/staging/erofs/utils.c b/drivers/staging/erofs/utils.c new file mode 100644 index 0000000..3dec4f8 --- /dev/null +++ b/drivers/staging/erofs/utils.c @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/drivers/staging/erofs/utils.c + * + * Copyright (C) 2018 HUAWEI, Inc. + * http://www.huawei.com/ + * Created by Gao Xiang + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of the Linux + * distribution for more details. + */ + +#include "internal.h" + +struct page *erofs_allocpage(struct list_head *pool, gfp_t gfp) +{ + struct page *page; + + if (!list_empty(pool)) { + page = lru_to_page(pool); + list_del(&page->lru); + } else { + page = alloc_pages(gfp | __GFP_NOFAIL, 0); + + BUG_ON(page == NULL); + BUG_ON(page->mapping != NULL); + } + return page; +} + -- 2.7.4