Commit 5dab600e authored by Andi Kleen's avatar Andi Kleen Committed by Linus Torvalds
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kfifo: document everywhere that size has to be power of two 



On my first try using them I missed that the fifos need to be power of
two, resulting in a runtime bug.  Document that requirement everywhere
(and fix one grammar bug)

Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Acked-by: default avatarStefani Seibold <stefani@seibold.net>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Andy Walls <awalls@radix.net>
Cc: Vikram Dhillon <dhillonv10@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d994ffc2

include/linux/kfifo.h

+2 −2
Original line number Diff line number Diff line
@@ -67,7 +67,7 @@ struct kfifo { 
/**

 * DECLARE_KFIFO - macro to declare a kfifo and the associated buffer

 * @name: name of the declared kfifo datatype

 * @size: size of the fifo buffer

 * @size: size of the fifo buffer. Must be a power of two.

 *

 * Note1: the macro can be used inside struct or union declaration

 * Note2: the macro creates two objects:
@@ -91,7 +91,7 @@ union { \ 
/**

 * DEFINE_KFIFO - macro to define and initialize a kfifo

 * @name: name of the declared kfifo datatype

 * @size: size of the fifo buffer

 * @size: size of the fifo buffer. Must be a power of two.

 *

 * Note1: the macro can be used for global and local kfifo data type variables

 * Note2: the macro creates two objects:

kernel/kfifo.c

+1 −1
Original line number Diff line number Diff line
@@ -41,7 +41,7 @@ static void _kfifo_init(struct kfifo *fifo, void *buffer, 
 * kfifo_init - initialize a FIFO using a preallocated buffer

 * @fifo: the fifo to assign the buffer

 * @buffer: the preallocated buffer to be used.

 * @size: the size of the internal buffer, this have to be a power of 2.

 * @size: the size of the internal buffer, this has to be a power of 2.

 *

 */

void kfifo_init(struct kfifo *fifo, void *buffer, unsigned int size)

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