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 <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 0f8a6b9..49f92bcd 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1089,7 +1089,9 @@
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 5090b90..9d9785a 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1931,6 +1931,7 @@
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;
@@ -1985,7 +1986,7 @@
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;
@@ -2105,8 +2106,8 @@
/* 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);
@@ -2114,7 +2115,7 @@
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 735122f..9217149 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1199,7 +1199,7 @@
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 212efc4..d5b32d0 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -276,7 +276,9 @@
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 5627e56..857dcc0 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -473,12 +473,16 @@
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 @@
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 f18b4ce..04b6045 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1596,21 +1596,28 @@
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 @@
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 @@
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 6c08a1d..d5ba0c9 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2356,7 +2356,8 @@
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);