* [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary @ 2013-11-22 7:48 Chao Yu 2013-11-27 5:29 ` Jaegeuk Kim 0 siblings, 1 reply; 8+ messages in thread From: Chao Yu @ 2013-11-22 7:48 UTC (permalink / raw) To: ???; +Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, 谭姝 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 <chao2.yu@samsung.com> --- 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) -- 1.7.9.5 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-22 7:48 [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary Chao Yu @ 2013-11-27 5:29 ` Jaegeuk Kim 2013-11-27 7:58 ` Chao Yu 0 siblings, 1 reply; 8+ messages in thread From: Jaegeuk Kim @ 2013-11-27 5:29 UTC (permalink / raw) To: Chao Yu; +Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, 谭姝 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 <chao2.yu@samsung.com> > --- > 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 ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-27 5:29 ` Jaegeuk Kim @ 2013-11-27 7:58 ` Chao Yu 2013-11-27 8:19 ` Jaegeuk Kim 0 siblings, 1 reply; 8+ messages in thread From: Chao Yu @ 2013-11-27 7:58 UTC (permalink / raw) To: jaegeuk.kim Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' 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 <chao2.yu@samsung.com> > > --- > > 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 ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-27 7:58 ` Chao Yu @ 2013-11-27 8:19 ` Jaegeuk Kim 2013-11-28 1:26 ` Chao Yu 0 siblings, 1 reply; 8+ messages in thread From: Jaegeuk Kim @ 2013-11-27 8:19 UTC (permalink / raw) To: Chao Yu Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' 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 <chao2.yu@samsung.com> > > > --- > > > 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 ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-27 8:19 ` Jaegeuk Kim @ 2013-11-28 1:26 ` Chao Yu 2013-11-28 3:33 ` Jaegeuk Kim 0 siblings, 1 reply; 8+ messages in thread From: Chao Yu @ 2013-11-28 1:26 UTC (permalink / raw) To: jaegeuk.kim Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' Hi Kim, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > Sent: Wednesday, November 27, 2013 4:19 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, > > 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 add all pages of page list to node_inode's address space by add_to_page_cache_lru() with arg sum_entry->nid? > > > > > > > > > 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? Got it, If we do not use the method above, we should search the NAT for nid number as the index of node_inode's page by the specified node page blkaddr, that costs a lot. How do you think? > > 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 <chao2.yu@samsung.com> > > > > --- > > > > 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 ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-28 1:26 ` Chao Yu @ 2013-11-28 3:33 ` Jaegeuk Kim 2013-11-28 5:56 ` Chao Yu 0 siblings, 1 reply; 8+ messages in thread From: Jaegeuk Kim @ 2013-11-28 3:33 UTC (permalink / raw) To: Chao Yu Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' Hi, 2013-11-28 (목), 09:26 +0800, Chao Yu: > Hi Kim, > > > -----Original Message----- > > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > > Sent: Wednesday, November 27, 2013 4:19 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, > > > > 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 add all pages of page list to node_inode's address space by > add_to_page_cache_lru() with arg sum_entry->nid? I don't think it's proper way to use add_to_page_cache_lru() directly. > > > > > > > > > > > > > > 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? > > Got it, > If we do not use the method above, we should search the NAT for nid number > as the index of node_inode's page by the specified node page blkaddr, that costs > a lot. > How do you think? 1. grab_cache_page(node_footer->nid); 2. memcpy(); 3. SetPageUptodate(); 4. f2fs_put_page(); Thanks, > > > > > 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 <chao2.yu@samsung.com> > > > > > --- > > > > > 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 > -- Jaegeuk Kim Samsung ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-28 3:33 ` Jaegeuk Kim @ 2013-11-28 5:56 ` Chao Yu 2013-11-30 5:12 ` Jaegeuk Kim 0 siblings, 1 reply; 8+ messages in thread From: Chao Yu @ 2013-11-28 5:56 UTC (permalink / raw) To: jaegeuk.kim Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' Hi, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > Sent: Thursday, November 28, 2013 11:33 AM > 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, > > 2013-11-28 (목), 09:26 +0800, Chao Yu: > > Hi Kim, > > > > > -----Original Message----- > > > From: Jaegeuk Kim [mailto:jaegeuk.kim@samsung.com] > > > Sent: Wednesday, November 27, 2013 4:19 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, > > > > > > 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 add all pages of page list to node_inode's address space by > > add_to_page_cache_lru() with arg sum_entry->nid? > > I don't think it's proper way to use add_to_page_cache_lru() directly. This is the way used in VM readahead(i.e. read_pages/mpage_readpages/ read_cache_pages). So what you worry about is that using lonely add_to_page_cache_lru() may cause exception, is it? > > > > > > > > > > > > > > > > > > > > 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? > > > > Got it, > > If we do not use the method above, we should search the NAT for nid number > > as the index of node_inode's page by the specified node page blkaddr, that costs > > a lot. > > How do you think? > > 1. grab_cache_page(node_footer->nid); > 2. memcpy(); > 3. SetPageUptodate(); > 4. f2fs_put_page(); It could be. This make ra_node_pages() synchronized, because we should read node_footer->nid from updated node page before we cache node pages, and we will still use page list to pass the updated page. Why not introduce f2fs_cache_node_pages() include your code to cache node pages after ra_node_pages()? Thanks, Yu > > Thanks, > > > > > > > > > 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 <chao2.yu@samsung.com> > > > > > > --- > > > > > > 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 > > > > -- > Jaegeuk Kim > Samsung ^ permalink raw reply [flat|nested] 8+ messages in thread
* RE: [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary 2013-11-28 5:56 ` Chao Yu @ 2013-11-30 5:12 ` Jaegeuk Kim 0 siblings, 0 replies; 8+ messages in thread From: Jaegeuk Kim @ 2013-11-30 5:12 UTC (permalink / raw) To: Chao Yu Cc: linux-fsdevel, linux-kernel, linux-f2fs-devel, '谭姝' Hi, [snip] > > > So how about add all pages of page list to node_inode's address space by > > > add_to_page_cache_lru() with arg sum_entry->nid? > > > > I don't think it's proper way to use add_to_page_cache_lru() directly. > > This is the way used in VM readahead(i.e. read_pages/mpage_readpages/ > read_cache_pages). > So what you worry about is that using lonely add_to_page_cache_lru() > may cause exception, is it? Right, what I meant was that, IMO, we should avoid copy and paste MM codes, but use its wrappers, exported symbols, as much as possible. > > > > > > > > > > > > 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? > > > > > > Got it, > > > If we do not use the method above, we should search the NAT for nid number > > > as the index of node_inode's page by the specified node page blkaddr, that costs > > > a lot. > > > How do you think? > > > > 1. grab_cache_page(node_footer->nid); > > 2. memcpy(); > > 3. SetPageUptodate(); > > 4. f2fs_put_page(); > > It could be. > > This make ra_node_pages() synchronized, because we should read node_footer->nid > from updated node page before we cache node pages, and we will still use page list to > pass the updated page. > > Why not introduce f2fs_cache_node_pages() include your code to cache node pages after > ra_node_pages()? Ok, right. I'll test again and then merge this patch. :) -- Jaegeuk Kim Samsung ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2013-11-30 5:13 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-11-22 7:48 [f2fs-dev] [PATCH] f2fs: readahead contiguous pages for restore_node_summary Chao Yu 2013-11-27 5:29 ` Jaegeuk Kim 2013-11-27 7:58 ` Chao Yu 2013-11-27 8:19 ` Jaegeuk Kim 2013-11-28 1:26 ` Chao Yu 2013-11-28 3:33 ` Jaegeuk Kim 2013-11-28 5:56 ` Chao Yu 2013-11-30 5:12 ` Jaegeuk Kim
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