From 57344fb5931e6651021d1e80e1117dd0f5a68734 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 4 Jun 2018 23:20:36 +0800 Subject: [PATCH] f2fs: let sync node IO interrupt async one Although mixed sync/async IOs can have continuous LBA, as they have different IO priority, block IO scheduler will add them into different queues and commit them separately, result in splited IOs which causes wrose performance. This patch gives high priority to synchronous IO of nodes, means that once synchronous flow starts, it can interrupt asynchronous writeback flow of system flusher, so more big IOs can be expected. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 2 ++ fs/f2fs/data.c | 9 +++++---- fs/f2fs/f2fs.h | 2 +- fs/f2fs/file.c | 2 ++ fs/f2fs/gc.c | 7 +++++++ fs/f2fs/node.c | 21 ++++++++++++++++++--- fs/f2fs/super.c | 3 ++- 7 files changed, 37 insertions(+), 9 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 0f8a6b96fc9c..49f92bcd8fe6 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -1089,7 +1089,9 @@ retry_flush_nodes: if (get_pages(sbi, F2FS_DIRTY_NODES)) { up_write(&sbi->node_write); + atomic_inc(&sbi->wb_sync_req[NODE]); err = f2fs_sync_node_pages(sbi, &wbc, false, FS_CP_NODE_IO); + atomic_dec(&sbi->wb_sync_req[NODE]); if (err) { up_write(&sbi->node_change); f2fs_unlock_all(sbi); diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index e429891b1e09..a8a1558b7689 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1933,6 +1933,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping, int ret = 0; int done = 0; struct pagevec pvec; + struct f2fs_sb_info *sbi = F2FS_M_SB(mapping); int nr_pages; pgoff_t uninitialized_var(writeback_index); pgoff_t index; @@ -1987,7 +1988,7 @@ retry: bool submitted = false; /* give a priority to WB_SYNC threads */ - if (atomic_read(&F2FS_M_SB(mapping)->wb_sync_req) && + if (atomic_read(&sbi->wb_sync_req[DATA]) && wbc->sync_mode == WB_SYNC_NONE) { done = 1; break; @@ -2107,8 +2108,8 @@ static int __f2fs_write_data_pages(struct address_space *mapping, /* to avoid spliting IOs due to mixed WB_SYNC_ALL and WB_SYNC_NONE */ if (wbc->sync_mode == WB_SYNC_ALL) - atomic_inc(&sbi->wb_sync_req); - else if (atomic_read(&sbi->wb_sync_req)) + atomic_inc(&sbi->wb_sync_req[DATA]); + else if (atomic_read(&sbi->wb_sync_req[DATA])) goto skip_write; blk_start_plug(&plug); @@ -2116,7 +2117,7 @@ static int __f2fs_write_data_pages(struct address_space *mapping, blk_finish_plug(&plug); if (wbc->sync_mode == WB_SYNC_ALL) - atomic_dec(&sbi->wb_sync_req); + atomic_dec(&sbi->wb_sync_req[DATA]); /* * if some pages were truncated, we cannot guarantee its mapping->host * to detect pending bios. diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index f167d01443fe..4c09e770a0a3 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1201,7 +1201,7 @@ struct f2fs_sb_info { struct percpu_counter alloc_valid_block_count; /* writeback control */ - atomic_t wb_sync_req; /* count # of WB_SYNC threads */ + atomic_t wb_sync_req[META]; /* count # of WB_SYNC threads */ /* valid inode count */ struct percpu_counter total_valid_inode_count; diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index fc60abbe940a..ebe8171b5d27 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -274,7 +274,9 @@ go_write: goto out; } sync_nodes: + atomic_inc(&sbi->wb_sync_req[NODE]); ret = f2fs_fsync_node_pages(sbi, inode, &wbc, atomic); + atomic_dec(&sbi->wb_sync_req[NODE]); if (ret) goto out; diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 5627e56a696f..857dcc05df64 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -473,12 +473,16 @@ static void gc_node_segment(struct f2fs_sb_info *sbi, block_t start_addr; int off; int phase = 0; + bool fggc = (gc_type == FG_GC); start_addr = START_BLOCK(sbi, segno); next_step: entry = sum; + if (fggc && phase == 2) + atomic_inc(&sbi->wb_sync_req[NODE]); + for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { nid_t nid = le32_to_cpu(entry->nid); struct page *node_page; @@ -525,6 +529,9 @@ next_step: if (++phase < 3) goto next_step; + + if (fggc) + atomic_dec(&sbi->wb_sync_req[NODE]); } /* diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index f18b4ce95c21..04b604591ef9 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1596,21 +1596,28 @@ int f2fs_sync_node_pages(struct f2fs_sb_info *sbi, int step = 0; int nwritten = 0; int ret = 0; - int nr_pages; + int nr_pages, done = 0; pagevec_init(&pvec, 0); next_step: index = 0; - while ((nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index, - PAGECACHE_TAG_DIRTY))) { + while (!done && (nr_pages = pagevec_lookup_tag(&pvec, + NODE_MAPPING(sbi), &index, PAGECACHE_TAG_DIRTY))) { int i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; bool submitted = false; + /* give a priority to WB_SYNC threads */ + if (atomic_read(&sbi->wb_sync_req[NODE]) && + wbc->sync_mode == WB_SYNC_NONE) { + done = 1; + break; + } + /* * flushing sequence with step: * 0. indirect nodes @@ -1738,6 +1745,11 @@ static int f2fs_write_node_pages(struct address_space *mapping, if (get_pages(sbi, F2FS_DIRTY_NODES) < nr_pages_to_skip(sbi, NODE)) goto skip_write; + if (wbc->sync_mode == WB_SYNC_ALL) + atomic_inc(&sbi->wb_sync_req[NODE]); + else if (atomic_read(&sbi->wb_sync_req[NODE])) + goto skip_write; + trace_f2fs_writepages(mapping->host, wbc, NODE); diff = nr_pages_to_write(sbi, NODE, wbc); @@ -1745,6 +1757,9 @@ static int f2fs_write_node_pages(struct address_space *mapping, f2fs_sync_node_pages(sbi, wbc, true, FS_NODE_IO); blk_finish_plug(&plug); wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff); + + if (wbc->sync_mode == WB_SYNC_ALL) + atomic_dec(&sbi->wb_sync_req[NODE]); return 0; skip_write: diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index cfa677acd412..f8b88089a3c4 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2356,7 +2356,8 @@ static void init_sb_info(struct f2fs_sb_info *sbi) for (i = 0; i < NR_COUNT_TYPE; i++) atomic_set(&sbi->nr_pages[i], 0); - atomic_set(&sbi->wb_sync_req, 0); + for (i = 0; i < META; i++) + atomic_set(&sbi->wb_sync_req[i], 0); INIT_LIST_HEAD(&sbi->s_list); mutex_init(&sbi->umount_mutex); -- 2.20.1