From fa9150a84ca333f68127097c4fa1eda4b3913a22 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Tue, 15 Jan 2013 16:45:24 +0900 Subject: f2fs: remove the blk_plug usage in f2fs_write_data_pages Let's consider the usage of blk_plug in f2fs_write_data_pages(). We can come up with the two issues: lock contention and task awareness. 1. Merging bios prior to grabing "queue lock" The f2fs merges consecutive IOs in the file system level before submitting any bios, which is similar with the back merge by the plugging mechanism in attempt_plug_merge(). Both of them need to acquire no queue lock. 2. Merging policy with respect to tasks The f2fs merges IOs as much as possible regardless of tasks, while blk-plugging is conducted on a basis of tasks. As we can understand there are trade-offs, f2fs tries to maximize the write performance with well-merged bios. As a result, if f2fs produces many consecutive but separated bios in writepages(), it would be good to use blk-plugging since f2fs would be able to avoid queue lock contention in the block layer by merging them. But, f2fs merges IOs and submit one bio, which means that there are not much chances to merge bios by attempt_plug_merge(). However, f2fs has already been used blk_plug by triggering generic_writepages() in f2fs_write_data_pages(). So to make the overall code consistency, I'd like to remove blk_plug there. Signed-off-by: Namjae Jeon Signed-off-by: Amit Sahrawat Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'fs/f2fs/data.c') diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 3aa5ce7cab8..b1347fc6d68 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -547,6 +547,15 @@ redirty_out: #define MAX_DESIRED_PAGES_WP 4096 +static int __f2fs_writepage(struct page *page, struct writeback_control *wbc, + void *data) +{ + struct address_space *mapping = data; + int ret = mapping->a_ops->writepage(page, wbc); + mapping_set_error(mapping, ret); + return ret; +} + static int f2fs_write_data_pages(struct address_space *mapping, struct writeback_control *wbc) { @@ -563,7 +572,7 @@ static int f2fs_write_data_pages(struct address_space *mapping, if (!S_ISDIR(inode->i_mode)) mutex_lock(&sbi->writepages); - ret = generic_writepages(mapping, wbc); + ret = write_cache_pages(mapping, wbc, __f2fs_writepage, mapping); if (!S_ISDIR(inode->i_mode)) mutex_unlock(&sbi->writepages); f2fs_submit_bio(sbi, DATA, (wbc->sync_mode == WB_SYNC_ALL)); -- cgit v1.2.3-70-g09d2 From c01e54b770e69c65525295eb2668be3dc0822406 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Thu, 17 Jan 2013 20:30:23 +0900 Subject: f2fs: support swapfile This patch adds f2fs_bmap operation to the data address space. This enables f2fs to support swapfile. Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/f2fs/data.c') diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index b1347fc6d68..7bd22a20112 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -698,6 +698,11 @@ static int f2fs_set_data_page_dirty(struct page *page) return 0; } +static sector_t f2fs_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping, block, get_data_block_ro); +} + const struct address_space_operations f2fs_dblock_aops = { .readpage = f2fs_read_data_page, .readpages = f2fs_read_data_pages, @@ -709,4 +714,5 @@ const struct address_space_operations f2fs_dblock_aops = { .invalidatepage = f2fs_invalidate_data_page, .releasepage = f2fs_release_data_page, .direct_IO = f2fs_direct_IO, + .bmap = f2fs_bmap, }; -- cgit v1.2.3-70-g09d2