writeback: remove the always false bdi_cap_writeback_dirty() test

This is dead code because no bdi flush thread will be started for
!bdi_cap_writeback_dirty bdi.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 9d5360c4c2afbe98d2b46112f131f90d943e00f5..0306c8e7d6b54b7449dd19497953a875d2b04990 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -614,7 +614,6 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
                                struct writeback_control *wbc)
 {
        struct super_block *sb = wbc->sb, *pin_sb = NULL;
-       const int is_blkdev_sb = sb_is_blkdev_sb(sb);
        const unsigned long start = jiffies;    /* livelock avoidance */
 
        spin_lock(&inode_lock);
@@ -635,23 +634,6 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
                        continue;
                }
 
-               if (!bdi_cap_writeback_dirty(wb->bdi)) {
-                       redirty_tail(inode);
-                       if (is_blkdev_sb) {
-                               /*
-                                * Dirty memory-backed blockdev: the ramdisk
-                                * driver does this.  Skip just this inode
-                                */
-                               continue;
-                       }
-                       /*
-                        * Dirty memory-backed inode against a filesystem other
-                        * than the kernel-internal bdev filesystem.  Skip the
-                        * entire superblock.
-                        */
-                       break;
-               }
-
                if (inode->i_state & (I_NEW | I_WILL_FREE)) {
                        requeue_io(inode);
                        continue;