diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index e52ceb1a73d3..99058eb81042 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -50,7 +50,13 @@
  *  bitmap_set(dst, pos, nbits)                 Set specified bit area
  *  bitmap_clear(dst, pos, nbits)               Clear specified bit area
  *  bitmap_find_next_zero_area(buf, len, pos, n, mask)  Find bit free area
- *  bitmap_find_next_zero_area_off(buf, len, pos, n, mask)  as above
+ *  bitmap_find_next_zero_area_off(buf, len, pos, n, mask, mask_off)  as above
+ *  bitmap_next_clear_region(map, &start, &end, nbits)  Find next clear region
+ *  bitmap_next_set_region(map, &start, &end, nbits)  Find next set region
+ *  bitmap_for_each_clear_region(map, rs, re, start, end)
+ *  						Iterate over all clear regions
+ *  bitmap_for_each_set_region(map, rs, re, start, end)
+ *  						Iterate over all set regions
  *  bitmap_shift_right(dst, src, n, nbits)      *dst = *src >> n
  *  bitmap_shift_left(dst, src, n, nbits)       *dst = *src << n
  *  bitmap_cut(dst, src, first, n, nbits)       Cut n bits from first, copy rest
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c
index 4f6c6ebbbbde..8d092609928e 100644
--- a/lib/percpu-refcount.c
+++ b/lib/percpu-refcount.c
@@ -50,9 +50,10 @@ static unsigned long __percpu *percpu_count_ptr(struct percpu_ref *ref)
  * @flags: PERCPU_REF_INIT_* flags
  * @gfp: allocation mask to use
  *
- * Initializes @ref.  If @flags is zero, @ref starts in percpu mode with a
- * refcount of 1; analagous to atomic_long_set(ref, 1).  See the
- * definitions of PERCPU_REF_INIT_* flags for flag behaviors.
+ * Initializes @ref.  @ref starts out in percpu mode with a refcount of 1 unless
+ * @flags contains PERCPU_REF_INIT_ATOMIC or PERCPU_REF_INIT_DEAD.  These flags
+ * change the start state to atomic with the latter setting the initial refcount
+ * to 0.  See the definitions of PERCPU_REF_INIT_* flags for flag behaviors.
  *
  * Note that @release must not sleep - it may potentially be called from RCU
  * callback context by percpu_ref_kill().
diff --git a/mm/percpu-stats.c b/mm/percpu-stats.c
index a5a8b22816ff..32558063c3f9 100644
--- a/mm/percpu-stats.c
+++ b/mm/percpu-stats.c
@@ -3,7 +3,7 @@
  * mm/percpu-debug.c
  *
  * Copyright (C) 2017		Facebook Inc.
- * Copyright (C) 2017		Dennis Zhou <dennisz@fb.com>
+ * Copyright (C) 2017		Dennis Zhou <dennis@kernel.org>
  *
  * Prints statistics about the percpu allocator and backing chunks.
  */
diff --git a/mm/percpu.c b/mm/percpu.c
index e9844086b236..d7e3bc649f4e 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -6,7 +6,7 @@
  * Copyright (C) 2009		Tejun Heo <tj@kernel.org>
  *
  * Copyright (C) 2017		Facebook Inc.
- * Copyright (C) 2017		Dennis Zhou <dennisszhou@gmail.com>
+ * Copyright (C) 2017		Dennis Zhou <dennis@kernel.org>
  *
  * The percpu allocator handles both static and dynamic areas.  Percpu
  * areas are allocated in chunks which are divided into units.  There is