Btrfs: Wait for async bio submissions to make some progress at queue time
Before, the btrfs bdi congestion function was used to test for too many
async bios. This keeps that check to throttle pdflush, but also
adds a check while queuing bios.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 92e14dd..bbba14b 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -429,7 +429,7 @@
return 0;
}
-static unsigned long async_submit_limit(struct btrfs_fs_info *info)
+unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
{
unsigned long limit = min_t(unsigned long,
info->workers.max_workers,
@@ -439,7 +439,8 @@
int btrfs_congested_async(struct btrfs_fs_info *info, int iodone)
{
- return atomic_read(&info->nr_async_bios) > async_submit_limit(info);
+ return atomic_read(&info->nr_async_bios) >
+ btrfs_async_submit_limit(info);
}
static void run_one_async_submit(struct btrfs_work *work)
@@ -451,12 +452,13 @@
async = container_of(work, struct async_submit_bio, work);
fs_info = BTRFS_I(async->inode)->root->fs_info;
- limit = async_submit_limit(fs_info);
+ limit = btrfs_async_submit_limit(fs_info);
limit = limit * 2 / 3;
atomic_dec(&fs_info->nr_async_submits);
- if (atomic_read(&fs_info->nr_async_submits) < limit)
+ if (atomic_read(&fs_info->nr_async_submits) < limit &&
+ waitqueue_active(&fs_info->async_submit_wait))
wake_up(&fs_info->async_submit_wait);
async->submit_bio_hook(async->inode, async->rw, async->bio,
@@ -469,7 +471,7 @@
extent_submit_bio_hook_t *submit_bio_hook)
{
struct async_submit_bio *async;
- int limit = async_submit_limit(fs_info);
+ int limit = btrfs_async_submit_limit(fs_info);
async = kmalloc(sizeof(*async), GFP_NOFS);
if (!async)
@@ -1863,10 +1865,10 @@
struct extent_io_tree *tree;
u64 num_dirty;
u64 start = 0;
- unsigned long thresh = 12 * 1024 * 1024;
+ unsigned long thresh = 96 * 1024 * 1024;
tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
- if (current_is_pdflush())
+ if (current_is_pdflush() || current->flags & PF_MEMALLOC)
return;
num_dirty = count_range_bits(tree, &start, (u64)-1,
