Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751104AbaLQPUA (ORCPT ); Wed, 17 Dec 2014 10:20:00 -0500 Received: from mail-la0-f42.google.com ([209.85.215.42]:45875 "EHLO mail-la0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905AbaLQPT6 (ORCPT ); Wed, 17 Dec 2014 10:19:58 -0500 MIME-Version: 1.0 In-Reply-To: <001d01d019e1$d6ad6c10$84084430$@samsung.com> References: <001d01d019e1$d6ad6c10$84084430$@samsung.com> Date: Thu, 18 Dec 2014 00:19:56 +0900 Message-ID: Subject: Re: [f2fs-dev] [PATCH v2] f2fs: use ra_meta_pages to simplify readahead code in restore_node_summary From: Changman Lee To: Chao Yu Cc: Jaegeuk Kim , Changman Lee , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Is there any reason to use truncate_inode_pages_range instead of invalidate_mapping_pages? IMHO, it seems nice to just use invalidate_mapping_pages because pages of meta_inode shouldn't be dirty, locked, under writeback or mapped in this function. If there is my misunderstanding, let me know. Thanks, Reviewed-by: Changman Lee 2014-12-17 19:10 GMT+09:00 Chao Yu : > Use more common function ra_meta_pages() with META_POR to readahead node blocks > in restore_node_summary() instead of ra_sum_pages(), hence we can simplify the > readahead code there, and also we can remove unused function ra_sum_pages(). > > changes from v1: > o fix one bug when using truncate_inode_pages_range which is pointed out by > Jaegeuk Kim. > > Signed-off-by: Chao Yu > --- > fs/f2fs/node.c | 68 +++++++++++++--------------------------------------------- > 1 file changed, 15 insertions(+), 53 deletions(-) > > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > index 5aa54a0..ab48b4c 100644 > --- a/fs/f2fs/node.c > +++ b/fs/f2fs/node.c > @@ -1726,80 +1726,42 @@ 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-read pages are allocated in bd_inode's mapping tree. > - */ > -static int ra_sum_pages(struct f2fs_sb_info *sbi, struct page **pages, > - int start, int nrpages) > -{ > - struct inode *inode = sbi->sb->s_bdev->bd_inode; > - struct address_space *mapping = inode->i_mapping; > - int i, page_idx = start; > - struct f2fs_io_info fio = { > - .type = META, > - .rw = READ_SYNC | REQ_META | REQ_PRIO > - }; > - > - for (i = 0; page_idx < start + nrpages; page_idx++, i++) { > - /* alloc page in bd_inode for reading node summary info */ > - pages[i] = grab_cache_page(mapping, page_idx); > - if (!pages[i]) > - break; > - f2fs_submit_page_mbio(sbi, pages[i], page_idx, &fio); > - } > - > - f2fs_submit_merged_bio(sbi, META, READ); > - return i; > -} > - > 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 inode *inode = sbi->sb->s_bdev->bd_inode; > block_t addr; > int bio_blocks = MAX_BIO_BLOCKS(sbi); > - struct page *pages[bio_blocks]; > - int i, idx, last_offset, nrpages, err = 0; > + int i, idx, last_offset, nrpages; > > /* scan the node segment */ > last_offset = sbi->blocks_per_seg; > addr = START_BLOCK(sbi, segno); > sum_entry = &sum->entries[0]; > > - for (i = 0; !err && i < last_offset; i += nrpages, addr += nrpages) { > + for (i = 0; i < last_offset; i += nrpages, addr += nrpages) { > nrpages = min(last_offset - i, bio_blocks); > > /* readahead node pages */ > - nrpages = ra_sum_pages(sbi, pages, addr, nrpages); > - if (!nrpages) > - return -ENOMEM; > + ra_meta_pages(sbi, addr, nrpages, META_POR); > > - for (idx = 0; idx < nrpages; idx++) { > - if (err) > - goto skip; > + for (idx = addr; idx < addr + nrpages; idx++) { > + struct page *page = get_meta_page(sbi, idx); > > - lock_page(pages[idx]); > - if (unlikely(!PageUptodate(pages[idx]))) { > - err = -EIO; > - } else { > - rn = F2FS_NODE(pages[idx]); > - sum_entry->nid = rn->footer.nid; > - sum_entry->version = 0; > - sum_entry->ofs_in_node = 0; > - sum_entry++; > - } > - unlock_page(pages[idx]); > -skip: > - page_cache_release(pages[idx]); > + rn = F2FS_NODE(page); > + sum_entry->nid = rn->footer.nid; > + sum_entry->version = 0; > + sum_entry->ofs_in_node = 0; > + sum_entry++; > + f2fs_put_page(page, 1); > } > > - invalidate_mapping_pages(inode->i_mapping, addr, > - addr + nrpages); > + truncate_inode_pages_range(META_MAPPING(sbi), > + addr << PAGE_CACHE_SHIFT, > + ((addr + nrpages) << PAGE_CACHE_SHIFT) - 1); > } > - return err; > + return 0; > } > > static void remove_nats_in_journal(struct f2fs_sb_info *sbi) > -- > 2.1.2 > > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel -- 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/