lib/lzo: 64-bit CTZ on arm64

LZO leaves some performance on the table by not realising that arm64 can
optimize count-trailing-zeros bit operations.

Add CONFIG_ARM64 to the checked definitions alongside CONFIG_X86_64 to
enable the use of rbit/clz instructions on full 64-bit quantities.

Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Matt Sealey <[email protected]>
Signed-off-by: Dave Rodgman <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Markus F.X.J. Oberhumer <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Nitin Gupta <[email protected]>
Cc: Richard Purdie <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Sonny Rao <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/lib/lzo/lzodefs.h b/lib/lzo/lzodefs.h
index 497f9c9f03a80ced87a629ca762a515d0dd911d3..00d1080155e4b22344674db7b2ced2eb0333d9a5 100644 (file)
--- a/lib/lzo/lzodefs.h
+++ b/lib/lzo/lzodefs.h
@@ -25,7 +25,7 @@
 
 #if defined(__BIG_ENDIAN) && defined(__LITTLE_ENDIAN)
 #error "conflicting endian definitions"
-#elif defined(CONFIG_X86_64)
+#elif defined(CONFIG_X86_64) || defined(CONFIG_ARM64)
 #define LZO_USE_CTZ64  1
 #define LZO_USE_CTZ32  1
 #elif defined(CONFIG_X86) || defined(CONFIG_PPC)