From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754593Ab3K0H7M (ORCPT ); Wed, 27 Nov 2013 02:59:12 -0500 Received: from mailout3.samsung.com ([203.254.224.33]:15217 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751952Ab3K0H7F convert rfc822-to-8bit (ORCPT ); Wed, 27 Nov 2013 02:59:05 -0500 X-AuditID: cbfee61b-b7f166d000007a34-34-5295a64794e8 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, =?utf-8?B?J+iwreWnnSc=?= References: <000101cee757$6f3b4790$4db1d6b0$@samsung.com> <1385530195.2417.22.camel@kjgkr> In-reply-to: <1385530195.2417.22.camel@kjgkr> Subject: RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary Date: Wed, 27 Nov 2013 15:58:05 +0800 Message-id: <002f01ceeb46$8758b9a0$960a2ce0$@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: AQLo/dmhZfpHUVdsz0A5xHDiq3ZS0QHeqe7fl/WCPtA= Content-language: zh-cn X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrFLMWRmVeSWpSXmKPExsVy+t9jQV33ZVODDObs1rC4vusvk8WlRe4W e/aeZLG4vGsOm0XrwvPMDqweuxd8ZvLo27KK0ePzJrkA5igum5TUnMyy1CJ9uwSujBv/m5gL /qlV/Grfy97A+FG2i5GTQ0LARGLemR+sELaYxIV769m6GLk4hASmM0q0HoZxfjBKfNt9ihGk ik1ARWJ5x38mEFtEQFpi1qd5LCBFzAKzGSV6vjwDKxISiJHYPvceG4jNKaArse72WzBbWCBa 4t2jHnYQm0VAVeLyn61gg3gFLCXWPbrNAmELSvyYfA/I5gAaqi4xZUouSJhZQFviybsLUJcq SOw4+5oR4gYriQcLnjJC1IhLbDxyi2UCo9AsJJNmIUyahWTSLCQdCxhZVjGKphYkFxQnpeca 6RUn5haX5qXrJefnbmIEx8Az6R2MqxosDjEKcDAq8fBOuDwlSIg1say4MvcQowQHs5IIr03P 1CAh3pTEyqrUovz4otKc1OJDjNIcLErivAdbrQOFBNITS1KzU1MLUotgskwcnFINjL0LWtZH yq2aWrR3e2CK3xdTpmd9vCHOjIcm7/tWFV0qFaEpLXqRJ+XvNKUCJg/t9rWuPodf/095t+b2 h+3TZ6UtnKTNKrROwvtLqvCxn9E7jgpM8F37dLnT4az9E9l+v+2pCLLljl0k7G/vsSZVaLeF +11/S9eQG0dD3A8WtHgtzpsfmhU4U4mlOCPRUIu5qDgRAK6DKdp9AgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kim, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > Sent: Wednesday, November 27, 2013 1:30 PM > To: Chao Yu > Cc: linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net; 谭姝 > Subject: Re: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary > > Hi Chao, > > It seems that we already have a readahed function for node pages, > ra_node_page(). > So, we don't make a page list for this, but can use the node_inode's > page cache. So you mean it's waste to release page list with updated data after we finish work in restore_node_summary, right? > > So how about writing ra_node_pages() which use the node_inode's page > cache? Hmm, so ra_node_pages is introduced for read node_inode's pages which are logical contiguously? and it also could take place of ra_node_page? > > Thanks, > > 2013-11-22 (금), 15:48 +0800, Chao Yu: > > If cp has no CP_UMOUNT_FLAG, we will read all pages in whole node segment > > one by one, it makes low performance. So let's merge contiguous pages and > > readahead for better performance. > > > > Signed-off-by: Chao Yu > > --- > > fs/f2fs/node.c | 89 +++++++++++++++++++++++++++++++++++++++----------------- > > 1 file changed, 63 insertions(+), 26 deletions(-) > > > > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > > index 4ac4150..81e704a 100644 > > --- a/fs/f2fs/node.c > > +++ b/fs/f2fs/node.c > > @@ -1572,47 +1572,84 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page) > > return 0; > > } > > > > +/* > > + * ra_sum_pages() merge contiguous pages into one bio and submit. > > + * these pre-readed pages are linked in pages list. > > + */ > > +static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages, > > + int start, int nrpages) > > +{ > > + struct page *page; > > + int page_idx = start; > > + > > + for (; page_idx < start + nrpages; page_idx++) { > > + /* alloc temporal page for read node summary info*/ > > + page = alloc_page(GFP_NOFS | __GFP_ZERO); > > + if (!page) { > > + struct page *tmp; > > + list_for_each_entry_safe(page, tmp, pages, lru) { > > + list_del(&page->lru); > > + unlock_page(page); > > + __free_pages(page, 0); > > + } > > + return -ENOMEM; > > + } > > + > > + lock_page(page); > > + page->index = page_idx; > > + list_add_tail(&page->lru, pages); > > + } > > + > > + list_for_each_entry(page, pages, lru) > > + submit_read_page(sbi, page, page->index, READ_SYNC); > > + > > + f2fs_submit_read_bio(sbi, READ_SYNC); > > + return 0; > > +} > > + > > 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; > > + struct page *page, *tmp; > > block_t addr; > > - int i, last_offset; > > - > > - /* alloc temporal page for read node */ > > - page = alloc_page(GFP_NOFS | __GFP_ZERO); > > - if (!page) > > - return -ENOMEM; > > - lock_page(page); > > + int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi)); > > + int i, last_offset, nrpages, err = 0; > > + LIST_HEAD(page_list); > > > > /* scan the node segment */ > > last_offset = sbi->blocks_per_seg; > > addr = START_BLOCK(sbi, segno); > > sum_entry = &sum->entries[0]; > > > > - for (i = 0; i < last_offset; i++, sum_entry++) { > > - /* > > - * In order to read next node page, > > - * we must clear PageUptodate flag. > > - */ > > - ClearPageUptodate(page); > > + for (i = 0; i < last_offset; i += nrpages, addr += nrpages) { > > > > - if (f2fs_readpage(sbi, page, addr, READ_SYNC)) > > - goto out; > > + nrpages = min(last_offset - i, bio_blocks); > > + /* read ahead node pages */ > > + err = ra_sum_pages(sbi, &page_list, addr, nrpages); > > + if (err) > > + return err; > > > > - lock_page(page); > > - rn = F2FS_NODE(page); > > - sum_entry->nid = rn->footer.nid; > > - sum_entry->version = 0; > > - sum_entry->ofs_in_node = 0; > > - addr++; > > + list_for_each_entry_safe(page, tmp, &page_list, lru) { > > + > > + lock_page(page); > > + if(PageUptodate(page)) { > > + rn = F2FS_NODE(page); > > + sum_entry->nid = rn->footer.nid; > > + sum_entry->version = 0; > > + sum_entry->ofs_in_node = 0; > > + sum_entry++; > > + } else { > > + err = -EIO; > > + } > > + > > + list_del(&page->lru); > > + unlock_page(page); > > + __free_pages(page, 0); > > + } > > } > > - unlock_page(page); > > -out: > > - __free_pages(page, 0); > > - return 0; > > + return err; > > } > > > > static bool flush_nats_in_journal(struct f2fs_sb_info *sbi) > > -- > Jaegeuk Kim > Samsung