Commit 06af1c52 authored Jan 20, 2016 by Bongkyu Kim Committed by Linus Torvalds Jan 20, 2016

lz4: fix wrong compress buffer size for 64-bits



The current lz4 compress buffer is 16kb on 32-bits, 32kb on 64-bits
system.  But, lz4 needs only 16kb on both.  On 64-bits, this causes
wasted cpu cycles for additional memset during every compression.

In case of lz4hc, the current buffer size is (256kb + 8) on 32-bits,
(512kb + 16) on 64-bits.  But, lz4hc needs only (256kb + 2 * pointer) on
both.

This patch fixes these wrong compress buffer sizes for 64-bits.

Signed-off-by: Bongkyu Kim <bongkyu.kim@lge.com>
Cc: Chanho Min <chanho.min@lge.com>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent a3b609ef

include/linux/lz4.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -9,8 +9,8 @@
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*/
		#define LZ4_MEM_COMPRESS (4096 * sizeof(unsigned char *))
		#define LZ4HC_MEM_COMPRESS (65538 * sizeof(unsigned char *))
		#define LZ4_MEM_COMPRESS (16384)
		#define LZ4HC_MEM_COMPRESS (262144 + (2 * sizeof(unsigned char *)))

		/*
		* lz4_compressbound()