From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752634Ab3K0FbA (ORCPT ); Wed, 27 Nov 2013 00:31:00 -0500 Received: from mailout4.samsung.com ([203.254.224.34]:47034 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751098Ab3K0Fa4 (ORCPT ); Wed, 27 Nov 2013 00:30:56 -0500 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfee690-b7f126d00000418c-f3-5295838ad346 Content-transfer-encoding: 8BIT Message-id: <1385530195.2417.22.camel@kjgkr> Subject: Re: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary From: Jaegeuk Kim Reply-to: jaegeuk.kim@samsung.com To: Chao Yu Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, =?UTF-8?Q?=E8=B0=AD=E5=A7=9D?= Date: Wed, 27 Nov 2013 14:29:55 +0900 In-reply-to: <000101cee757$6f3b4790$4db1d6b0$@samsung.com> References: <000101cee757$6f3b4790$4db1d6b0$@samsung.com> Organization: Samsung X-Mailer: Evolution 3.2.3-0ubuntu6 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrPIsWRmVeSWpSXmKPExsVy+t8zfd2u5qlBBu83qlj8b/rIZnFpkbvF nr0nWSwu75rDZtG68DyzA6vH7gWfmTz6tqxi9Pi8SS6AOYrLJiU1J7MstUjfLoErY9eDH4wF XfIVR5+nNjC+E+9i5OSQEDCR2P7+PRuELSZx4d56IJuLQ0hgGaPEmtUrGWGKLvz6yAiRWMQo 8eDDO7AEr4CgxI/J91i6GDk4mAXkJY5cygYJMwuoS0yat4gZov4Vo0TLiy/MEPU6Eu+W/APb JiwQLdG26ScTSC+bgLbE5v0GIGEhAUWJt/vvsoLYIgJKEr/mL2IFmcMssJBR4uCCm2C9LAKq Es9bOsBsTgEriZ9d71ggmi0lVnasBdvFLyAqcXjhdmaIB5Qkdrd3soMMkhA4xy4xuacbapCA xLfJh8AekBCQldh0AKpeUuLgihssExglZiF5cxbCm7OQvLmAkXkVo2hqQXJBcVJ6kYlecWJu cWleul5yfu4mRkjkTdjBeO+A9SHGZKCNE5mlRJPzgZGbVxJvaGxmZGFqYmpsZG5pRpqwkjiv 2qOkICGB9MSS1OzU1ILUovii0pzU4kOMTBycUg2M6fd1FTwkaldpB25jjXv0Mf18dN53HSm/ DMnn2t+PWEuYqwbXTWb2K06tv3lm96pv7EmOHgndegVJmce054ftN2PWNXY7UHdp4R2bM3GH 74R0NP24E160iT0ucV1GncnZ/X/cm7X/ramIcp5T5tek1SZ0527P4/tXeTme6IRH6hTEcL6S TlBiKc5INNRiLipOBAAArYR60gIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprDKsWRmVeSWpSXmKPExsVy+t9jAd2u5qlBBovvylr8b/rIZnFpkbvF nr0nWSwu75rDZtG68DyzA6vH7gWfmTz6tqxi9Pi8SS6AOaqB0SYjNTEltUghNS85PyUzL91W yTs43jne1MzAUNfQ0sJcSSEvMTfVVsnFJ0DXLTMHaKWSQlliTilQKCCxuFhJ3w7ThNAQN10L mMYIXd+QILgeIwM0kLCOMWPXgx+MBV3yFUefpzYwvhPvYuTkkBAwkbjw6yMjhC0mceHeerYu Ri4OIYFFjBIPPrwDS/AKCEr8mHyPpYuRg4NZQF7iyKVskDCzgLrEpHmLmCHqXzFKtLz4wgxR ryPxbsk/NhBbWCBaom3TTyaQXjYBbYnN+w1AwkICihJv999lBbFFBJQkfs1fxAoyh1lgIaPE wQU3wXpZBFQlnrd0gNmcAlYSP7vesUA0W0qs7FgLtotfQFTi8MLtzBAPKEnsbu9kn8AoNAvJ 2bMQzp6F5OwFjMyrGEVTC5ILipPSc430ihNzi0vz0vWS83M3MYLj+pn0DsZVDRaHGAU4GJV4 eCdcnhIkxJpYVlyZe4hRgoNZSYQ3vHJqkBBvSmJlVWpRfnxRaU5q8SHGZKDDJzJLiSbnA1NO Xkm8obGJmZGlkZmFkYm5OWnCSuK8B1utA4UE0hNLUrNTUwtSi2C2MHFwSjUwrp676Iahxs/X y50OyBxk3Pimcf9LzdbdM1jO1k4Xji2YsKg37velynlnrLPf729drLr7ee3BAzlrvZh7lS9O e/1F08G6wu6QzRnh0A75Ame5LE/NMlupy1vV2L9tPVy0+YjL800zT37e78a2IE1g7Z/QrXk7 WBpZsqdk+S62lfsvOW/mtLtLTZVYijMSDbWYi4oTAetoT7MvAwAA DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 how about writing ra_node_pages() which use the node_inode's page cache? 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