From ba206a026ff4cd0f11033ccaa4bf99c30567ded4 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 1 Jun 2020 21:47:05 -0700 Subject: btrfs: convert from readpages to readahead Implement the new readahead method in btrfs using the new readahead_page_batch() function. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton Reviewed-by: William Kucharski Cc: Chao Yu Cc: Christoph Hellwig Cc: Cong Wang Cc: Darrick J. Wong Cc: Dave Chinner Cc: Eric Biggers Cc: Gao Xiang Cc: Jaegeuk Kim Cc: John Hubbard Cc: Joseph Qi Cc: Junxiao Bi Cc: Michal Hocko Cc: Zi Yan Cc: Johannes Thumshirn Cc: Miklos Szeredi Link: http://lkml.kernel.org/r/20200414150233.24495-18-willy@infradead.org Signed-off-by: Linus Torvalds --- fs/btrfs/extent_io.c | 43 ++++++++++++------------------------------- fs/btrfs/extent_io.h | 3 +-- fs/btrfs/inode.c | 16 +++++++--------- 3 files changed, 20 insertions(+), 42 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 39e45b8a5031..fc46adf2f5bf 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4367,51 +4367,32 @@ int extent_writepages(struct address_space *mapping, return ret; } -int extent_readpages(struct address_space *mapping, struct list_head *pages, - unsigned nr_pages) +void extent_readahead(struct readahead_control *rac) { struct bio *bio = NULL; unsigned long bio_flags = 0; struct page *pagepool[16]; struct extent_map *em_cached = NULL; - int nr = 0; u64 prev_em_start = (u64)-1; + int nr; - while (!list_empty(pages)) { - u64 contig_end = 0; - - for (nr = 0; nr < ARRAY_SIZE(pagepool) && !list_empty(pages);) { - struct page *page = lru_to_page(pages); - - prefetchw(&page->flags); - list_del(&page->lru); - if (add_to_page_cache_lru(page, mapping, page->index, - readahead_gfp_mask(mapping))) { - put_page(page); - break; - } - - pagepool[nr++] = page; - contig_end = page_offset(page) + PAGE_SIZE - 1; - } - - if (nr) { - u64 contig_start = page_offset(pagepool[0]); + while ((nr = readahead_page_batch(rac, pagepool))) { + u64 contig_start = page_offset(pagepool[0]); + u64 contig_end = page_offset(pagepool[nr - 1]) + PAGE_SIZE - 1; - ASSERT(contig_start + nr * PAGE_SIZE - 1 == contig_end); + ASSERT(contig_start + nr * PAGE_SIZE - 1 == contig_end); - contiguous_readpages(pagepool, nr, contig_start, - contig_end, &em_cached, &bio, &bio_flags, - &prev_em_start); - } + contiguous_readpages(pagepool, nr, contig_start, contig_end, + &em_cached, &bio, &bio_flags, &prev_em_start); } if (em_cached) free_extent_map(em_cached); - if (bio) - return submit_one_bio(bio, 0, bio_flags); - return 0; + if (bio) { + if (submit_one_bio(bio, 0, bio_flags)) + return; + } } /* diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 2ed65bd0760e..25594e09fdcd 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -198,8 +198,7 @@ int extent_writepages(struct address_space *mapping, struct writeback_control *wbc); int btree_write_cache_pages(struct address_space *mapping, struct writeback_control *wbc); -int extent_readpages(struct address_space *mapping, struct list_head *pages, - unsigned nr_pages); +void extent_readahead(struct readahead_control *rac); int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, __u64 start, __u64 len); void set_page_extent_mapped(struct page *page); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 320d1062068d..ba0aa8b4ad09 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4856,8 +4856,8 @@ static void evict_inode_truncate_pages(struct inode *inode) /* * Keep looping until we have no more ranges in the io tree. - * We can have ongoing bios started by readpages (called from readahead) - * that have their endio callback (extent_io.c:end_bio_extent_readpage) + * We can have ongoing bios started by readahead that have + * their endio callback (extent_io.c:end_bio_extent_readpage) * still in progress (unlocked the pages in the bio but did not yet * unlocked the ranges in the io tree). Therefore this means some * ranges can still be locked and eviction started because before @@ -7050,11 +7050,11 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend, * for it to complete) and then invalidate the pages for * this range (through invalidate_inode_pages2_range()), * but that can lead us to a deadlock with a concurrent - * call to readpages() (a buffered read or a defrag call + * call to readahead (a buffered read or a defrag call * triggered a readahead) on a page lock due to an * ordered dio extent we created before but did not have * yet a corresponding bio submitted (whence it can not - * complete), which makes readpages() wait for that + * complete), which makes readahead wait for that * ordered extent to complete while holding a lock on * that page. */ @@ -8293,11 +8293,9 @@ static int btrfs_writepages(struct address_space *mapping, return extent_writepages(mapping, wbc); } -static int -btrfs_readpages(struct file *file, struct address_space *mapping, - struct list_head *pages, unsigned nr_pages) +static void btrfs_readahead(struct readahead_control *rac) { - return extent_readpages(mapping, pages, nr_pages); + extent_readahead(rac); } static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) @@ -10553,7 +10551,7 @@ static const struct address_space_operations btrfs_aops = { .readpage = btrfs_readpage, .writepage = btrfs_writepage, .writepages = btrfs_writepages, - .readpages = btrfs_readpages, + .readahead = btrfs_readahead, .direct_IO = btrfs_direct_IO, .invalidatepage = btrfs_invalidatepage, .releasepage = btrfs_releasepage, -- cgit v1.2.3-70-g09d2 From d1b89bc0426110138ddc80a6916f359d0174571d Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Mon, 1 Jun 2020 21:47:45 -0700 Subject: btrfs: use attach/detach_page_private Since the new pair function is introduced, we can call them to clean the code in btrfs. Signed-off-by: Guoqing Jiang Signed-off-by: Andrew Morton Reviewed-by: Andrew Morton Acked-by: David Sterba Cc: Chris Mason Cc: Josef Bacik Link: http://lkml.kernel.org/r/20200517214718.468-4-guoqing.jiang@cloud.ionos.com Signed-off-by: Linus Torvalds --- fs/btrfs/disk-io.c | 4 +--- fs/btrfs/extent_io.c | 21 ++++++--------------- fs/btrfs/inode.c | 23 +++++------------------ 3 files changed, 12 insertions(+), 36 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index d10c7be10f3b..7278789ff8a7 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -980,9 +980,7 @@ static void btree_invalidatepage(struct page *page, unsigned int offset, btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info, "page private not zero on page %llu", (unsigned long long)page_offset(page)); - ClearPagePrivate(page); - set_page_private(page, 0); - put_page(page); + detach_page_private(page); } } diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index fc46adf2f5bf..e12eb32d9e17 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3076,22 +3076,16 @@ static int submit_extent_page(unsigned int opf, static void attach_extent_buffer_page(struct extent_buffer *eb, struct page *page) { - if (!PagePrivate(page)) { - SetPagePrivate(page); - get_page(page); - set_page_private(page, (unsigned long)eb); - } else { + if (!PagePrivate(page)) + attach_page_private(page, eb); + else WARN_ON(page->private != (unsigned long)eb); - } } void set_page_extent_mapped(struct page *page) { - if (!PagePrivate(page)) { - SetPagePrivate(page); - get_page(page); - set_page_private(page, EXTENT_PAGE_PRIVATE); - } + if (!PagePrivate(page)) + attach_page_private(page, (void *)EXTENT_PAGE_PRIVATE); } static struct extent_map * @@ -4910,10 +4904,7 @@ static void btrfs_release_extent_buffer_pages(struct extent_buffer *eb) * We need to make sure we haven't be attached * to a new eb. */ - ClearPagePrivate(page); - set_page_private(page, 0); - /* One for the page private */ - put_page(page); + detach_page_private(page); } if (mapped) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index ba0aa8b4ad09..8b3489f229c7 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8301,11 +8301,8 @@ static void btrfs_readahead(struct readahead_control *rac) static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) { int ret = try_release_extent_mapping(page, gfp_flags); - if (ret == 1) { - ClearPagePrivate(page); - set_page_private(page, 0); - put_page(page); - } + if (ret == 1) + detach_page_private(page); return ret; } @@ -8327,14 +8324,8 @@ static int btrfs_migratepage(struct address_space *mapping, if (ret != MIGRATEPAGE_SUCCESS) return ret; - if (page_has_private(page)) { - ClearPagePrivate(page); - get_page(newpage); - set_page_private(newpage, page_private(page)); - set_page_private(page, 0); - put_page(page); - SetPagePrivate(newpage); - } + if (page_has_private(page)) + attach_page_private(newpage, detach_page_private(page)); if (PagePrivate2(page)) { ClearPagePrivate2(page); @@ -8456,11 +8447,7 @@ again: } ClearPageChecked(page); - if (PagePrivate(page)) { - ClearPagePrivate(page); - set_page_private(page, 0); - put_page(page); - } + detach_page_private(page); } /* -- cgit v1.2.3-70-g09d2