Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754822Ab1DKM2J (ORCPT ); Mon, 11 Apr 2011 08:28:09 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:44117 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751944Ab1DKM2H (ORCPT ); Mon, 11 Apr 2011 08:28:07 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=X9xvyTKKzQbNilplEz6mr6R+irnc3k1qXG7vlowpDiceTMNc9Y29T6SYLoFYLDO9Gm IitdxzRnraKNTrF1YLOHh4wsZLuoZe7FWA+x/Du5JfqYNM9vrqXHBHo5n29wP7qZOktA fTOKjL4b39v6V1MUQ9JfTKy+crbUfdqvnKrGg= From: Namhyung Kim To: Hugh Dickins Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH] shmem: factor out remove_indirect_page() Date: Mon, 11 Apr 2011 21:27:59 +0900 Message-Id: <1302524879-4737-1-git-send-email-namhyung@gmail.com> X-Mailer: git-send-email 1.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3983 Lines: 121 Split out some common code in shmem_truncate_range() in order to improve readability (hopefully) and to reduce code duplication. Signed-off-by: Namhyung Kim --- mm/shmem.c | 62 ++++++++++++++++++++++++++++++++++------------------------- 1 files changed, 36 insertions(+), 26 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 58da7c150ba6..58ad1159678f 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -531,6 +531,31 @@ static void shmem_free_pages(struct list_head *next) } while (next); } +/** + * remove_indirect_page - remove a indirect page from upper layer + * @dir: pointer to the indirect page in the upper layer + * @page: indirect page to be removed + * @needs_lock: pointer to spinlock if needed + * @free_list: list which the removed page will be inserted into + * + * This function removes @page from @dir and insert it into @free_list. + * The @page still remains after this function but will not be seen by + * other tasks. Finally it will be freed via shmem_free_pages(). + */ +static void remove_indirect_page(struct page **dir, struct page *page, + spinlock_t *needs_lock, struct list_head *free_list) +{ + if (needs_lock) { + spin_lock(needs_lock); + *dir = NULL; + spin_unlock(needs_lock); + } else { + *dir = NULL; + } + + list_add(&page->lru, free_list); +} + static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) { struct shmem_inode_info *info = SHMEM_I(inode); @@ -582,9 +607,9 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) topdir = info->i_indirect; if (topdir && idx <= SHMEM_NR_DIRECT && !punch_hole) { - info->i_indirect = NULL; + remove_indirect_page(&info->i_indirect, topdir, NULL, + &pages_to_free); nr_pages_to_free++; - list_add(&topdir->lru, &pages_to_free); } spin_unlock(&info->lock); @@ -637,15 +662,10 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) diroff = ((idx - ENTRIES_PER_PAGEPAGE/2) % ENTRIES_PER_PAGEPAGE) / ENTRIES_PER_PAGE; if (!diroff && !offset && upper_limit >= stage) { - if (needs_lock) { - spin_lock(needs_lock); - *dir = NULL; - spin_unlock(needs_lock); - needs_lock = NULL; - } else - *dir = NULL; + remove_indirect_page(dir, middir, needs_lock, + &pages_to_free); nr_pages_to_free++; - list_add(&middir->lru, &pages_to_free); + needs_lock = NULL; } shmem_dir_unmap(dir); dir = shmem_dir_map(middir); @@ -672,15 +692,10 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) if (punch_hole) needs_lock = &info->lock; if (upper_limit >= stage) { - if (needs_lock) { - spin_lock(needs_lock); - *dir = NULL; - spin_unlock(needs_lock); - needs_lock = NULL; - } else - *dir = NULL; + remove_indirect_page(dir, middir, needs_lock, + &pages_to_free); nr_pages_to_free++; - list_add(&middir->lru, &pages_to_free); + needs_lock = NULL; } shmem_dir_unmap(dir); cond_resched(); @@ -690,15 +705,10 @@ static void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end) punch_lock = needs_lock; subdir = dir[diroff]; if (subdir && !offset && upper_limit-idx >= ENTRIES_PER_PAGE) { - if (needs_lock) { - spin_lock(needs_lock); - dir[diroff] = NULL; - spin_unlock(needs_lock); - punch_lock = NULL; - } else - dir[diroff] = NULL; + remove_indirect_page(&dir[diroff], subdir, needs_lock, + &pages_to_free); nr_pages_to_free++; - list_add(&subdir->lru, &pages_to_free); + punch_lock = NULL; } if (subdir && page_private(subdir) /* has swap entries */) { size = limit - idx; -- 1.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/