The patch titled
Subject: lib/lzo: 64-bit CTZ on arm64
has been added to the -mm tree. Its filename is
lib-lzo-64-bit-ctz-on-arm64.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/lib-lzo-64-bit-ctz-on-arm64.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/lib-lzo-64-bit-ctz-on-arm64.patch
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------------------------------------------------------
From: Matt Sealey <matt.sealey@xxxxxxx>
Subject: 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/20181127161913.23863-5-dave.rodgman@xxxxxxx
Signed-off-by: Matt Sealey <matt.sealey@xxxxxxx>
Signed-off-by: Dave Rodgman <dave.rodgman@xxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Markus F.X.J. Oberhumer <markus@xxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nitin Gupta <nitingupta910@xxxxxxxxx>
Cc: Richard Purdie <rpurdie@xxxxxxxxxxxxxx>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@xxxxxxxxx>
Cc: Sonny Rao <sonnyrao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/lib/lzo/lzodefs.h~lib-lzo-64-bit-ctz-on-arm64
+++ a/lib/lzo/lzodefs.h
@@ -28,7 +28,7 @@
#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)
_
Patches currently in -mm which might be from matt.sealey@xxxxxxx are
lib-lzo-clean-up-by-introducing-copy16.patch
lib-lzo-enable-64-bit-ctz-on-arm.patch
lib-lzo-64-bit-ctz-on-arm64.patch
lib-lzo-fast-8-byte-copy-on-arm64.patch
