The maximum number of concurrent work items queued on commit_wq is
bound by the number of active journals.  Convert to alloc_workqueue()
and use the default concurrency level so that they can be processed in
parallel.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: reiserfs-devel@vger.kernel.org
        reiserfs_mounted_fs_count++;
        if (reiserfs_mounted_fs_count <= 1) {
                reiserfs_write_unlock(sb);
-               commit_wq = create_workqueue("reiserfs");
+               commit_wq = alloc_workqueue("reiserfs", WQ_MEM_RECLAIM, 0);
                reiserfs_write_lock(sb);
        }