From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752937Ab3LJJoa (ORCPT ); Tue, 10 Dec 2013 04:44:30 -0500 Received: from mailout1.samsung.com ([203.254.224.24]:30612 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751565Ab3LJJo0 convert rfc822-to-8bit (ORCPT ); Tue, 10 Dec 2013 04:44:26 -0500 X-AuditID: cbfee61b-b7f006d000003e1f-e6-52a6e278c76d From: Chao Yu To: jaegeuk.kim@samsung.com Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net References: <000a01cef4a0$9f2d64a0$dd882de0$@samsung.com> <1386576057.2101.106.camel@kjgkr> <000c01cef54a$80fef2a0$82fcd7e0$@samsung.com> In-reply-to: <000c01cef54a$80fef2a0$82fcd7e0$@samsung.com> Subject: RE: [f2fs-dev] [PATCH 3/3 V3] f2fs: introduce f2fs_cache_node_page() to add page into node_inode cache Date: Tue, 10 Dec 2013 17:43:33 +0800 Message-id: <000d01cef58c$66be09c0$343a1d40$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 Content-transfer-encoding: 8BIT X-Mailer: Microsoft Outlook 14.0 Thread-index: AQJKxSoRdvYRcRdRLlc/mnXOEGcC1wEMD/ZEAg72+V2ZPLPjcA== Content-language: zh-cn X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrGLMWRmVeSWpSXmKPExsVy+t9jQd2KR8uCDFpPiFlc3/WXyeLSIneL PXtPslhc3jWHzYHFY/eCz0wefVtWMXp83iQXwBzFZZOSmpNZllqkb5fAlbH18kOWghM6FW+f SzUwPlXqYuTkkBAwkZhy+gobhC0mceHeeiCbi0NIYDqjxKQfF5kgnB+MEs+PPWYFqWITUJFY 3vGfCcQWEZCWmPVpHguIzSyQKTHn9WRWiIZuRonTpx4ygyQ4Bawk7i/8A9YgLFAocaTtBVgD i4CqxKu7u8FW8wpYSlx9eR/KFpT4Mfke1FB1iUnzFjFD2NoST95dYIU4VUFix9nXjBBHOEns fXYfql5cYuORWywTGIVmIRk1C8moWUhGzULSsoCRZRWjaGpBckFxUnqukV5xYm5xaV66XnJ+ 7iZGcOg/k97BuKrB4hCjAAejEg+vxL+lQUKsiWXFlbmHGCU4mJVEeFefXBYkxJuSWFmVWpQf X1Sak1p8iFGag0VJnPdgq3WgkEB6YklqdmpqQWoRTJaJgxMYGZocP6YWTNkYqOdXuSNrs/68 lZyWXXGLJp/9wdBeu2ptXZ9bOi9zlUdsyklDU2G1XtM7NgrCLXNPZC6o6/Epl65ukd5evKRX wlbqhtV/yXBN8ahd5a0rAssnem3SOXNGasNO3a8fZWwd7qWddq4/9qWIs9/4jGHBo1Pvf7Hf vZj1wVvE86KpEktxRqKhFnNRcSIAGARk0XkCAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: Chao Yu [mailto:chao2.yu@samsung.com] > Sent: Tuesday, December 10, 2013 9:52 AM > To: jaegeuk.kim@samsung.com > Cc: linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net > Subject: Re: [f2fs-dev] [PATCH 3/3 V3] f2fs: introduce f2fs_cache_node_page() to add page into node_inode cache > > Hi, > > > -----Original Message----- > > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > > Sent: Monday, December 09, 2013 4:01 PM > > To: Chao Yu > > Cc: linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net > > Subject: Re: [f2fs-dev] [PATCH 3/3 V3] f2fs: introduce f2fs_cache_node_page() to add page into node_inode cache > > > > Hi, > > > > Sorry for the noise. > > Once I tested this patch, I recognized that I made a mistake: > > > > f2fs_fill_super() > > 1. build_segment_manager() > > -> restore_node_summary() > > -> NULL pointer exception, due to no NAT cache. > > 2. build_node_manager() > > > > So, we should not call get_node_info() prior to build_node_manager(). > > And, it's not easy to change the order of build_*_manager simply. > > > > Let's consider in more details. > > Before we call restore_node_summary(), we have read HOT_DATA > Summary. It means already we got the NAT cache in curseg. > Although we could not call get_node_info() directly, we still could use > NAT cache in HOT_DATA curseg. > > So how about using this cache to verify validity of page like this? > > f2fs_cache_node_page() > if(!looup_nat_curseg_cache()) > return; Code of verification is missed here. if (curseg cache blk_addr != current blkaddr) return; > grab_cache_page(); > memcpy(); > SetPageUptodate(); > f2fs_put_page(); > > > Thanks, > > > > 2013-12-09 (월), 13:35 +0800, Chao Yu: > > > This patch introduces f2fs_cache_node_page(), in this function, page which is > > > readed ahead will be copy to node_inode's mapping cache. > > > It will avoid rereading these node pages. > > > > > > change log: > > > o check validity of page by searching NAT suggested by Jaegeuk Kim. > > > o add 'unlikely' for compiler optimization suggested by Jaegeuk Kim. > > > > > > Suggested-by: Jaegeuk Kim > > > Signed-off-by: Chao Yu > > > --- > > > fs/f2fs/node.c | 39 ++++++++++++++++++++++++++++++++++++++- > > > 1 file changed, 38 insertions(+), 1 deletion(-) > > > > > > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > > > index 099f06f..4c6da98 100644 > > > --- a/fs/f2fs/node.c > > > +++ b/fs/f2fs/node.c > > > @@ -1600,13 +1600,46 @@ static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages, > > > return 0; > > > } > > > > > > +/* > > > + * f2fs_cache_node_page() check validaty of input page by searching NAT. > > > + * Then, it will copy updated data of vaild page to node_inode cache. > > > + */ > > > +void f2fs_cache_node_page(struct f2fs_sb_info *sbi, struct page *page, > > > + nid_t nid, block_t blkaddr) > > > +{ > > > + struct address_space *mapping = sbi->node_inode->i_mapping; > > > + struct page *npage; > > > + struct node_info ni; > > > + > > > + get_node_info(sbi, nid, &ni); > > > + > > > + if (ni.blk_addr != blkaddr) > > > + return; > > > + > > > + npage = grab_cache_page(mapping, nid); > > > + if (unlikely(!npage)) > > > + return; > > > + > > > + if (PageUptodate(npage)) { > > > + f2fs_put_page(npage, 1); > > > + return; > > > + } > > > + > > > + memcpy(page_address(npage), page_address(page), PAGE_CACHE_SIZE); > > > + > > > + SetPageUptodate(npage); > > > + f2fs_put_page(npage, 1); > > > + > > > + return; > > > +} > > > + > > > int restore_node_summary(struct f2fs_sb_info *sbi, > > > unsigned int segno, struct f2fs_summary_block *sum) > > > { > > > struct f2fs_node *rn; > > > struct f2fs_summary *sum_entry; > > > struct page *page, *tmp; > > > - block_t addr; > > > + block_t addr, blkaddr; > > > int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi)); > > > int i, last_offset, nrpages, err = 0; > > > LIST_HEAD(page_list); > > > @@ -1624,6 +1657,7 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > if (err) > > > return err; > > > > > > + blkaddr = addr; > > > list_for_each_entry_safe(page, tmp, &page_list, lru) { > > > > > > lock_page(page); > > > @@ -1633,6 +1667,8 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > sum_entry->version = 0; > > > sum_entry->ofs_in_node = 0; > > > sum_entry++; > > > + f2fs_cache_node_page(sbi, page, > > > + le32_to_cpu(rn->footer.nid), blkaddr); > > > } else { > > > err = -EIO; > > > } > > > @@ -1640,6 +1676,7 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > list_del(&page->lru); > > > unlock_page(page); > > > __free_pages(page, 0); > > > + blkaddr++; > > > } > > > } > > > return err; > > > > -- > > Jaegeuk Kim > > Samsung > > > ------------------------------------------------------------------------------ > Sponsored by Intel(R) XDK > Develop, test and display web and hybrid apps with a single code base. > Download it for free now! > http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel