From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755010Ab3K0IUY (ORCPT ); Wed, 27 Nov 2013 03:20:24 -0500 Received: from mailout4.samsung.com ([203.254.224.34]:32125 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752608Ab3K0IUV (ORCPT ); Wed, 27 Nov 2013 03:20:21 -0500 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfee68e-b7f7e6d00000477d-04-5295ab430a3c Content-transfer-encoding: 8BIT Message-id: <1385540365.2417.28.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?=27=E8=B0=AD=E5=A7=9D=27?= Date: Wed, 27 Nov 2013 17:19:25 +0900 In-reply-to: <002f01ceeb46$8758b9a0$960a2ce0$@samsung.com> References: <000101cee757$6f3b4790$4db1d6b0$@samsung.com> <1385530195.2417.22.camel@kjgkr> <002f01ceeb46$8758b9a0$960a2ce0$@samsung.com> Organization: Samsung X-Mailer: Evolution 3.2.3-0ubuntu6 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrAIsWRmVeSWpSXmKPExsVy+t8zY13n1VODDN5cM7X43/SRzeLSIneL PXtPslhc3jWHzaJ14XlmB1aP3Qs+M3n0bVnF6PF5k1wAcxSXTUpqTmZZapG+XQJXxs5ZX9gL TmtX3PjWy9rAeFmhi5GTQ0LARGLb2knMELaYxIV769m6GLk4hASWMUqcWLmYHaboX9cxVhBb SGARo8T0hTYgNq+AoMSPyfdYuhg5OJgF5CWOXMoGCTMLqEtMmreIGWLOK0aJ7QevM0PU60hs utbABGILC0RLvHvUww7SyyagLbF5vwHEeEWJt/vvgq0SEVCS+DV/ESvIHGaB5YwSzyefYwFJ sAioSsz5PxvM5hSwkpj97CMLxLIuRome7WfBjuYXEJU4vHA71GdKErvbO9lBiiQELrFLXN+7 BWqSgMS3yYfAPpAQkJXYdACqXlLi4IobLBMYJWYh+XMWwp+zkPy5gJF5FaNoakFyQXFSepGR XnFibnFpXrpecn7uJkZI7PXtYLx5wPoQYzLQxonMUqLJ+cDYzSuJNzQ2M7IwNTE1NjK3NCNN WEmcd9HDpCAhgfTEktTs1NSC1KL4otKc1OJDjEwcnFINjB4W1r5NL8u5v4vsTbv4ZcKXzBe5 Rs82W2tvL4/l3BZ8/eqR67P51vBufNV4qWvZgaO5X04bzghbqHVlV8/qSZZn3JIvq9zanu5w LyDrloGF2+/Fp/54NiXvfTzhZbRCVt78T+nu6Qeu7bsjc8VJ2uliUku1T4Tt20XmEruWHVi4 5tHOPy33OW8psRRnJBpqMRcVJwIAig+P/tMCAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprLKsWRmVeSWpSXmKPExsVy+t9jAV3n1VODDGbcM7D43/SRzeLSIneL PXtPslhc3jWHzaJ14XlmB1aP3Qs+M3n0bVnF6PF5k1wAc1QDo01GamJKapFCal5yfkpmXrqt kndwvHO8qZmBoa6hpYW5kkJeYm6qrZKLT4CuW2YO0EolhbLEnFKgUEBicbGSvh2mCaEhbroW MI0Rur4hQXA9RgZoIGEdY8bOWV/YC05rV9z41svawHhZoYuRk0NCwETiX9cxVghbTOLCvfVs ILaQwCJGiekLbUBsXgFBiR+T77F0MXJwMAvISxy5lA0SZhZQl5g0bxFzFyMXUPkrRontB68z Q9TrSGy61sAEYgsLREu8e9TDDtLLJqAtsXm/AcR4RYm3+++CrRURUJL4NX8RK8gcZoHljBLP J59jAUmwCKhKzPk/G8zmFLCSmP3sIwvEsi5GiZ7tZ9lBEvwCohKHF25nhnhASWJ3eyf7BEah WUjunoVw9ywkdy9gZF7FKJpakFxQnJSea6hXnJhbXJqXrpecn7uJERzZz6R2MK5ssDjEKMDB qMTDO+HylCAh1sSy4srcQ4wSHMxKIrw2PVODhHhTEiurUovy44tKc1KLDzEmA10+kVlKNDkf mHTySuINjU3MjCyNzCyMTMzNSRNWEuc90GodKCSQnliSmp2aWpBaBLOFiYNTqoFRgimZeVLO HrXNWvlvy/9Jsva6X3pZ5qT4SPP1zdr+0GsnX94U1V8eru+e/+WE9c9eydgEHUXzhcFqB97+ Pv78vsDs0t31e6xqf3w8K6dUan2cw0s+qJDTpOu6tZ1f0cIfaTGPnvP+zSnOOK6t8PPX+hf8 ohIdVcmpfq82rGdOfub0p0daoV6JpTgj0VCLuag4EQBgFgpvMAMAAA== 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, 2013-11-27 (수), 15:58 +0800, Chao Yu: > 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? 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? Ah. The ra_node_page() read a node page ahead for a given node id. So it doesn't match exactly between ra_node_page() and ra_node_pages() that I suggested. So how about reading node pages and then caching some of them in the page cache, node_inode's address space? Thanks, > > > > > > 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 > -- Jaegeuk Kim Samsung