Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:53254 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753084AbaIPFcs (ORCPT ); Tue, 16 Sep 2014 01:32:48 -0400 From: NeilBrown To: Peter Zijlstra , Andrew Morton , Trond Myklebust , Ingo Molnar Date: Tue, 16 Sep 2014 15:31:35 +1000 Subject: [PATCH 2/4] MM: export page_wakeup functions Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton Message-ID: <20140916053135.22257.22693.stgit@notabene.brown> In-Reply-To: <20140916051911.22257.24658.stgit@notabene.brown> References: <20140916051911.22257.24658.stgit@notabene.brown> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: This will allow NFS to wait for PG_private to be cleared and, particularly, to send a wake-up when it is. Signed-off-by: NeilBrown --- include/linux/pagemap.h | 10 ++++++++-- mm/filemap.c | 8 ++------ 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 87f9e4230d3a..2dca0cef3506 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -496,8 +496,8 @@ static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm, } /* - * This is exported only for wait_on_page_locked/wait_on_page_writeback. - * Never use this directly! + * This is exported only for wait_on_page_locked/wait_on_page_writeback, + * and for filesystems which need to wait on PG_private. */ extern void wait_on_page_bit(struct page *page, int bit_nr); @@ -512,6 +512,12 @@ static inline int wait_on_page_locked_killable(struct page *page) return 0; } +extern wait_queue_head_t *page_waitqueue(struct page *page); +static inline void wake_up_page(struct page *page, int bit) +{ + __wake_up_bit(page_waitqueue(page), &page->flags, bit); +} + /* * Wait for a page to be unlocked. * diff --git a/mm/filemap.c b/mm/filemap.c index 4a19c084bdb1..c9ba09f2ad3c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -670,17 +670,13 @@ EXPORT_SYMBOL(__page_cache_alloc); * at a cost of "thundering herd" phenomena during rare hash * collisions. */ -static wait_queue_head_t *page_waitqueue(struct page *page) +wait_queue_head_t *page_waitqueue(struct page *page) { const struct zone *zone = page_zone(page); return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)]; } - -static inline void wake_up_page(struct page *page, int bit) -{ - __wake_up_bit(page_waitqueue(page), &page->flags, bit); -} +EXPORT_SYMBOL(page_waitqueue); void wait_on_page_bit(struct page *page, int bit_nr) {