Btrfs: Count async bios separately from async checksum work items

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index c88f1e1..bb4a8d2 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -544,6 +544,7 @@ struct btrfs_fs_info {
        struct list_head hashers;
        struct list_head dead_roots;
        atomic_t nr_async_submits;
+       atomic_t nr_async_bios;
 
        /*
         * this is used by the balancing code to wait for all the pending

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 99bd9f9..9902d29 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -429,6 +429,21 @@ int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
        return 0;
 }
 
+static int congested_async(struct btrfs_fs_info *info, int iodone)
+{
+       int limit = 256 * info->fs_devices->open_devices;
+
+       if (iodone)
+               limit = (limit * 3) / 2;
+       if (atomic_read(&info->nr_async_submits) > limit)
+               return 1;
+
+       limit = 8192 * info->fs_devices->open_devices;
+       if (iodone)
+               limit = (limit * 3) / 2;
+       return atomic_read(&info->nr_async_bios) > limit;
+}
+
 static void run_one_async_submit(struct btrfs_work *work)
 {
        struct btrfs_fs_info *fs_info;
@@ -437,6 +452,11 @@ static void run_one_async_submit(struct btrfs_work *work)
        async = container_of(work, struct  async_submit_bio, work);
        fs_info = BTRFS_I(async->inode)->root->fs_info;
        atomic_dec(&fs_info->nr_async_submits);
+
+       if ((async->bio->bi_rw & (1 << BIO_RW)) &&
+           !congested_async(fs_info, 1)) {
+               clear_bdi_congested(&fs_info->bdi, WRITE);
+       }
        async->submit_bio_hook(async->inode, async->rw, async->bio,
                               async->mirror_num);
        kfree(async);
@@ -938,15 +958,13 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 {
        struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
        int ret = 0;
-       int limit = 256 * info->fs_devices->open_devices;
        struct list_head *cur;
        struct btrfs_device *device;
        struct backing_dev_info *bdi;
 
        if ((bdi_bits & (1 << BDI_write_congested)) &&
-           atomic_read(&info->nr_async_submits) > limit) {
+           congested_async(info, 0))
                return 1;
-       }
 
        list_for_each(cur, &info->fs_devices->devices) {
                device = list_entry(cur, struct btrfs_device, dev_list);
@@ -1250,6 +1268,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
        INIT_LIST_HEAD(&fs_info->space_info);
        btrfs_mapping_init(&fs_info->mapping_tree);
        atomic_set(&fs_info->nr_async_submits, 0);
+       atomic_set(&fs_info->nr_async_bios, 0);
        atomic_set(&fs_info->throttles, 0);
        atomic_set(&fs_info->throttle_gen, 0);
        fs_info->sb = sb;

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 09311b3..23a5b0a 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -179,7 +179,7 @@ loop:
                cur = pending;
                pending = pending->bi_next;
                cur->bi_next = NULL;
-               atomic_dec(&device->dev_root->fs_info->nr_async_submits);
+               atomic_dec(&device->dev_root->fs_info->nr_async_bios);
 
                BUG_ON(atomic_read(&cur->bi_cnt) == 0);
                bio_get(cur);
@@ -2145,12 +2145,12 @@ int schedule_bio(struct btrfs_root *root, struct btrfs_device *device,
        }
 
        /*
-        * nr_async_sumbits allows us to reliably return congestion to the
+        * nr_async_bios allows us to reliably return congestion to the
         * higher layers.  Otherwise, the async bio makes it appear we have
         * made progress against dirty pages when we've really just put it
         * on a queue for later
         */
-       atomic_inc(&root->fs_info->nr_async_submits);
+       atomic_inc(&root->fs_info->nr_async_bios);
        WARN_ON(bio->bi_next);
        bio->bi_next = NULL;
        bio->bi_rw |= rw;