writeback: get rid to incorrect references to pdflush in comments

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/buffer.c b/fs/buffer.c
index 90a9886..fc22b45 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -274,7 +274,7 @@
 }
 
 /*
- * Kick pdflush then try to free up some ZONE_NORMAL memory.
+ * Kick the writeback threads then try to free up some ZONE_NORMAL memory.
  */
 static void free_more_memory(void)
 {
@@ -1699,9 +1699,9 @@
 		/*
 		 * If it's a fully non-blocking write attempt and we cannot
 		 * lock the buffer then redirty the page.  Note that this can
-		 * potentially cause a busy-wait loop from pdflush and kswapd
-		 * activity, but those code paths have their own higher-level
-		 * throttling.
+		 * potentially cause a busy-wait loop from writeback threads
+		 * and kswapd activity, but those code paths have their own
+		 * higher-level throttling.
 		 */
 		if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
 			lock_buffer(bh);
@@ -3191,7 +3191,7 @@
  * still running obsolete flush daemons, so we terminate them here.
  *
  * Use of bdflush() is deprecated and will be removed in a future kernel.
- * The `pdflush' kernel threads fully replace bdflush daemons and this call.
+ * The `flush-X' kernel threads fully replace bdflush daemons and this call.
  */
 SYSCALL_DEFINE2(bdflush, int, func, long, data)
 {
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 15e375b..15944f7 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -320,7 +320,7 @@
 	 * For inodes being constantly redirtied, dirtied_when can get stuck.
 	 * It _appears_ to be in the future, but is actually in distant past.
 	 * This test is necessary to prevent such wrapped-around relative times
-	 * from permanently stopping the whole pdflush writeback.
+	 * from permanently stopping the whole bdi writeback.
 	 */
 	ret = ret && time_before_eq(inode->dirtied_when, jiffies);
 #endif
@@ -1085,9 +1085,6 @@
  * If older_than_this is non-NULL, then only write out inodes which
  * had their first dirtying at a time earlier than *older_than_this.
  *
- * If we're a pdlfush thread, then implement pdflush collision avoidance
- * against the entire list.
- *
  * If `bdi' is non-zero then we're being asked to writeback a specific queue.
  * This function assumes that the blockdev superblock's inodes are backed by
  * a variety of queues, so all inodes are searched.  For other superblocks,