From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751837AbaE0HWU (ORCPT ); Tue, 27 May 2014 03:22:20 -0400 Received: from mailout3.samsung.com ([203.254.224.33]:26786 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750884AbaE0HWR (ORCPT ); Tue, 27 May 2014 03:22:17 -0400 X-AuditID: cbfee68f-b7fef6d000003970-c1-53843d265b82 Date: Tue, 27 May 2014 16:20:48 +0900 From: Changman Lee To: Chao Yu Cc: "'Jaegeuk Kim'" , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH v2] f2fs: avoid crash when trace f2fs_submit_page_mbio event in ra_sum_pages Message-id: <20140527072048.GC4886@cm224.lee> References: <00f501cf7944$7e8a65d0$7b9f3170$@samsung.com> <20140527012505.GA4886@cm224.lee> <00ff01cf7975$a5f5fd10$f1e1f730$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-disposition: inline In-reply-to: <00ff01cf7975$a5f5fd10$f1e1f730$@samsung.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrJIsWRmVeSWpSXmKPExsVy+t8zA11125Zgg1ZTi/9NH9ksru/6y2Rx aZG7xZ69J1ksLu+aw+bA6rF7wWcmj74tqxg9Pm+SC2CO4rJJSc3JLEst0rdL4MrYs/UYe0Gf ZcW9ltlMDYzndLoYOTkkBEwkVjScZYewxSQu3FvP1sXIxSEksIxR4uCf7+wwRTcfr2eHSExn lJiy4BULhPOTUWLq69ksIFUsAqoSjXuugNlsAloS7afXgtkiAkoSv+YvYgVpYBaYxCix5Gcz UIKDQ1ggV6LjhB5IDa+ArsSSiXehNnQzSqxq+cMIkRCU+DH5HtggZqCh63ceZ4KwpSUe/Z0B dh6ngJXE3t+HwGpEBVQkppzcxgZx9iZ2iRNtzhDHCUh8m3wIbK+EgKzEpgPMECWSEgdX3GCZ wCg2C8m2WUi2zUKybQEj8ypG0dSC5ILipPQiY73ixNzi0rx0veT83E2MkGjq38F494D1IcZk oJUTmaVEk/OB0ZhXEm9obGZkYWpiamxkbmlGmrCSOO/9h0lBQgLpiSWp2ampBalF8UWlOanF hxiZODilGhiDZWQjrv6JMzFo5pPm5DAu377212v2VpP+G592uG77veLfBJ/i7fPyldUrfe9/ uLLwPrtVYerEzXenqV1ZJq53/dbkKalGD/YUGP7WVH4QtoXZOdSxyO4/j97+lWdip55bU2K4 9/VbmTjWw79+rn1p9ujqoeI24bL9a85btH2oMEv9fmLChaCrSizFGYmGWsxFxYkAHqQ/P7wC AAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupgleLIzCtJLcpLzFFi42I5/e+xoK6abUuwwfbH5hb/mz6yWVzf9ZfJ 4tIid4s9e0+yWFzeNYfNgdVj94LPTB59W1YxenzeJBfAHNXAaJORmpiSWqSQmpecn5KZl26r 5B0c7xxvamZgqGtoaWGupJCXmJtqq+TiE6DrlpkDtFJJoSwxpxQoFJBYXKykb4dpQmiIm64F TGOErm9IEFyPkQEaSFjHmLFn6zH2gj7Linsts5kaGM/pdDFyckgImEjcfLyeHcIWk7hwbz1b FyMXh5DAdEaJKQtesUA4Pxklpr6ezQJSxSKgKtG45wqYzSagJdF+ei2YLSKgJPFr/iJWkAZm gUmMEkt+NgMlODiEBXIlOk7ogdTwCuhKLJl4lx1iaDejxKqWP4wQCUGJH5PvgQ1iBhq6fudx JghbWuLR3xlg53EKWEns/X0IrEZUQEViysltbBMYBWYhaZ+FpH0WkvYFjMyrGEVTC5ILipPS cw31ihNzi0vz0vWS83M3MYLj9ZnUDsaVDRaHGAU4GJV4eCf4NgcLsSaWFVfmHmKU4GBWEuGN ZWoJFuJNSaysSi3Kjy8qzUktPsSYDAyOicxSosn5wFSSVxJvaGxiZmRpZGZhZGJuTpqwkjjv gVbrQCGB9MSS1OzU1ILUIpgtTBycUg2M27K9j50zef7q/PtFBSFRulULMz7tfLhSSvVA5yf5 LnmPW+9iVCd/PrxWPa9Gd+9p2ynLPp3w0fKqrHvn83XdlXMrFSd0P8z1Xr7gMIff/Ctzoj8t W/ahwPJpXOVRRuP51efvr+B6e/TYqR3f5YKYnOb1muRLbJG0NrLVM9rnyahjolSxvnjiMyWW 4oxEQy3mouJEAHTAQacbAwAA 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 On Tue, May 27, 2014 at 02:32:57PM +0800, Chao Yu wrote: > Hi changman, > > > -----Original Message----- > > From: Changman Lee [mailto:cm224.lee@samsung.com] > > Sent: Tuesday, May 27, 2014 9:25 AM > > To: Chao Yu > > Cc: Jaegeuk Kim; linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; > > linux-f2fs-devel@lists.sourceforge.net > > Subject: Re: [f2fs-dev] [PATCH v2] f2fs: avoid crash when trace f2fs_submit_page_mbio event > > in ra_sum_pages > > > > Hi, Chao > > > > Could you think about following once. > > move node_inode in front of build_segment_manager, then use node_inode > > instead of bd_inode. > > Jaegeuk and I discussed this solution previously in > [PATCH 3/3 V3] f2fs: introduce f2fs_cache_node_page() to add page into node_inode cache > > You can see it from this url: > http://sourceforge.net/p/linux-f2fs/mailman/linux-f2fs-devel/?viewmonth=201312&page=5 > > And it seems not easy to change order of build_*_manager and make node_inode, > because there are dependency between them. > Sorry to make a mess your patch thread. I've understood it. In your patch, using NAT journal seems to be possible. Anyway, thanks for your answer. > > > > On Tue, May 27, 2014 at 08:41:07AM +0800, Chao Yu wrote: > > > Previously we allocate pages with no mapping in ra_sum_pages(), so we may > > > encounter a crash in event trace of f2fs_submit_page_mbio where we access > > > mapping data of the page. > > > > > > We'd better allocate pages in bd_inode mapping and invalidate these pages after > > > we restore data from pages. It could avoid crash in above scenario. > > > > > > Changes from V1 > > > o remove redundant code in ra_sum_pages() suggested by Jaegeuk Kim. > > > > > > Call Trace: > > > [] ? ftrace_raw_event_f2fs_write_checkpoint+0x80/0x80 [f2fs] > > > [] f2fs_submit_page_mbio+0x1cb/0x200 [f2fs] > > > [] restore_node_summary+0x13a/0x280 [f2fs] > > > [] build_curseg+0x2bd/0x620 [f2fs] > > > [] build_segment_manager+0x1cb/0x920 [f2fs] > > > [] f2fs_fill_super+0x535/0x8e0 [f2fs] > > > [] mount_bdev+0x16a/0x1a0 > > > [] f2fs_mount+0x1f/0x30 [f2fs] > > > [] mount_fs+0x36/0x170 > > > [] vfs_kern_mount+0x55/0xe0 > > > [] do_mount+0x1e8/0x900 > > > [] SyS_mount+0x82/0xc0 > > > [] sysenter_do_call+0x12/0x22 > > > > > > Suggested-by: Jaegeuk Kim > > > Signed-off-by: Chao Yu > > > --- > > > fs/f2fs/node.c | 52 ++++++++++++++++++++++++---------------------------- > > > 1 file changed, 24 insertions(+), 28 deletions(-) > > > > > > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > > > index 3d60d3d..02a59e9 100644 > > > --- a/fs/f2fs/node.c > > > +++ b/fs/f2fs/node.c > > > @@ -1658,35 +1658,29 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page) > > > > > > /* > > > * ra_sum_pages() merge contiguous pages into one bio and submit. > > > - * these pre-readed pages are linked in pages list. > > > + * these pre-readed pages are alloced in bd_inode's mapping tree. > > > */ > > > -static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages, > > > +static int ra_sum_pages(struct f2fs_sb_info *sbi, struct page **pages, > > > int start, int nrpages) > > > { > > > - struct page *page; > > > - int page_idx = start; > > > + 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 (; page_idx < start + nrpages; page_idx++) { > > > - /* alloc temporal page for read node summary info*/ > > > - page = alloc_page(GFP_F2FS_ZERO); > > > - if (!page) > > > + 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; > > > - > > > - lock_page(page); > > > - page->index = page_idx; > > > - list_add_tail(&page->lru, pages); > > > + f2fs_submit_page_mbio(sbi, pages[i], page_idx, &fio); > > > } > > > > > > - list_for_each_entry(page, pages, lru) > > > - f2fs_submit_page_mbio(sbi, page, page->index, &fio); > > > - > > > f2fs_submit_merged_bio(sbi, META, READ); > > > - > > > - return page_idx - start; > > > + return i; > > > } > > > > > > int restore_node_summary(struct f2fs_sb_info *sbi, > > > @@ -1694,11 +1688,11 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > { > > > struct f2fs_node *rn; > > > struct f2fs_summary *sum_entry; > > > - struct page *page, *tmp; > > > + struct inode *inode = sbi->sb->s_bdev->bd_inode; > > > block_t addr; > > > int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi)); > > > - int i, last_offset, nrpages, err = 0; > > > - LIST_HEAD(page_list); > > > + struct page *pages[bio_blocks]; > > > + int i, idx, last_offset, nrpages, err = 0; > > > > > > /* scan the node segment */ > > > last_offset = sbi->blocks_per_seg; > > > @@ -1709,29 +1703,31 @@ int restore_node_summary(struct f2fs_sb_info *sbi, > > > nrpages = min(last_offset - i, bio_blocks); > > > > > > /* read ahead node pages */ > > > - nrpages = ra_sum_pages(sbi, &page_list, addr, nrpages); > > > + nrpages = ra_sum_pages(sbi, pages, addr, nrpages); > > > if (!nrpages) > > > return -ENOMEM; > > > > > > - list_for_each_entry_safe(page, tmp, &page_list, lru) { > > > + for (idx = 0; idx < nrpages; idx++) { > > > if (err) > > > goto skip; > > > > > > - lock_page(page); > > > - if (unlikely(!PageUptodate(page))) { > > > + lock_page(pages[idx]); > > > + if (unlikely(!PageUptodate(pages[idx]))) { > > > err = -EIO; > > > } else { > > > - rn = F2FS_NODE(page); > > > + 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(page); > > > + unlock_page(pages[idx]); > > > skip: > > > - list_del(&page->lru); > > > - __free_pages(page, 0); > > > + page_cache_release(pages[idx]); > > > } > > > + > > > + invalidate_mapping_pages(inode->i_mapping, addr, > > > + addr + nrpages); > > > } > > > return err; > > > } > > > -- > > > 1.7.9.5 > > > > > > > > > > > > ------------------------------------------------------------------------------ > > > The best possible search technologies are now affordable for all companies. > > > Download your FREE open source Enterprise Search Engine today! > > > Our experts will assist you in its installation for $59/mo, no commitment. > > > Test it for FREE on our Cloud platform anytime! > > > http://pubads.g.doubleclick.net/gampad/clk?id=145328191&iu=/4140/ostg.clktrk > > > _______________________________________________ > > > Linux-f2fs-devel mailing list > > > Linux-f2fs-devel@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel