diff options
author | Joakim Tjernlund <[email protected]> | 2010-01-08 14:42:40 -0800 |
---|---|---|
committer | Linus Torvalds <[email protected]> | 2010-01-11 09:34:04 -0800 |
commit | ac4c2a3bbe5db5fc570b1d0ee1e474db7cb22585 (patch) | |
tree | a7b8f2d618497cd4152ebe8e7390107a442bf0f6 | |
parent | 129182e5626972ac0df85d43a36dd46ad61c64e1 (diff) |
zlib: optimize inffast when copying direct from output
JFFS2 uses lesser compression ratio and inflate always ends up in "copy
direct from output" case.
This patch tries to optimize the direct copy procedure. Uses
get_unaligned() but only in one place.
The copy loop just above this one can also use this optimization, but I
havn't done so as I have not tested if it is a win there too.
On my MPC8321 this is about 17% faster on my JFFS2 root FS than the
original.
[[email protected]: coding-style fixes]
Signed-off-by: Joakim Tjernlund <[email protected]>
Cc: Roel Kluin <[email protected]>
Cc: Richard Purdie <[email protected]>
Cc: David Woodhouse <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
-rw-r--r-- | arch/powerpc/boot/Makefile | 4 | ||||
-rw-r--r-- | lib/zlib_inflate/inffast.c | 55 |
2 files changed, 47 insertions, 12 deletions
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile index bb2465bcb327..826a30a00f59 100644 --- a/arch/powerpc/boot/Makefile +++ b/arch/powerpc/boot/Makefile @@ -20,7 +20,7 @@ all: $(obj)/zImage BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ - -fno-strict-aliasing -Os -msoft-float -pipe \ + -fno-strict-aliasing -Os -msoft-float -pipe -D__KERNEL__\ -fomit-frame-pointer -fno-builtin -fPIC -nostdinc \ -isystem $(shell $(CROSS32CC) -print-file-name=include) BOOTAFLAGS := -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc @@ -34,6 +34,8 @@ BOOTCFLAGS += -fno-stack-protector endif BOOTCFLAGS += -I$(obj) -I$(srctree)/$(obj) +BOOTCFLAGS += -include include/linux/autoconf.h -Iarch/powerpc/include +BOOTCFLAGS += -Iinclude DTS_FLAGS ?= -p 1024 diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c index 8550b0c05d00..05e1559fa156 100644 --- a/lib/zlib_inflate/inffast.c +++ b/lib/zlib_inflate/inffast.c @@ -4,6 +4,8 @@ */ #include <linux/zutil.h> +#include <asm/unaligned.h> +#include <asm/byteorder.h> #include "inftrees.h" #include "inflate.h" #include "inffast.h" @@ -24,9 +26,11 @@ #ifdef POSTINC # define OFF 0 # define PUP(a) *(a)++ +# define UP_UNALIGNED(a) get_unaligned((a)++) #else # define OFF 1 # define PUP(a) *++(a) +# define UP_UNALIGNED(a) get_unaligned(++(a)) #endif /* @@ -239,18 +243,47 @@ void inflate_fast(z_streamp strm, unsigned start) } } else { + unsigned short *sout; + unsigned long loops; + from = out - dist; /* copy direct from output */ - do { /* minimum length is three */ - PUP(out) = PUP(from); - PUP(out) = PUP(from); - PUP(out) = PUP(from); - len -= 3; - } while (len > 2); - if (len) { - PUP(out) = PUP(from); - if (len > 1) - PUP(out) = PUP(from); - } + /* minimum length is three */ + /* Align out addr */ + if (!((long)(out - 1 + OFF) & 1)) { + PUP(out) = PUP(from); + len--; + } + sout = (unsigned short *)(out - OFF); + if (dist > 2) { + unsigned short *sfrom; + + sfrom = (unsigned short *)(from - OFF); + loops = len >> 1; + do + PUP(sout) = UP_UNALIGNED(sfrom); + while (--loops); + out = (unsigned char *)sout + OFF; + from = (unsigned char *)sfrom + OFF; + } else { /* dist == 1 or dist == 2 */ + unsigned short pat16; + + pat16 = *(sout-2+2*OFF); + if (dist == 1) +#if defined(__BIG_ENDIAN) + pat16 = (pat16 & 0xff) | ((pat16 & 0xff) << 8); +#elif defined(__LITTLE_ENDIAN) + pat16 = (pat16 & 0xff00) | ((pat16 & 0xff00) >> 8); +#else +#error __BIG_ENDIAN nor __LITTLE_ENDIAN is defined +#endif + loops = len >> 1; + do + PUP(sout) = pat16; + while (--loops); + out = (unsigned char *)sout + OFF; + } + if (len & 1) + PUP(out) = PUP(from); } } else if ((op & 64) == 0) { /* 2nd level distance code */ |