[mirror_zfs.git] / module / zcommon / zfs_fletcher_sse.c

/*
 * Implement fast Fletcher4 with SSE2,SSSE3 instructions. (x86)
 *
 * Use the 128-bit SSE2/SSSE3 SIMD instructions and registers to compute
 * Fletcher4 in two incremental 64-bit parallel accumulator streams,
 * and then combine the streams to form the final four checksum words.
 * This implementation is a derivative of the AVX SIMD implementation by
 * James Guilford and Jinshan Xiong from Intel (see zfs_fletcher_intel.c).
 *
 * Copyright (C) 2016 Tyler J. Stachecki.
 *
 * Authors:
 *	Tyler J. Stachecki <stachecki.tyler@gmail.com>
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#if defined(HAVE_SSE2)

#include <linux/simd_x86.h>
#include <sys/spa_checksum.h>
#include <sys/byteorder.h>
#include <sys/strings.h>
#include <zfs_fletcher.h>

static void
fletcher_4_sse2_init(fletcher_4_ctx_t *ctx)
{
	bzero(ctx->sse, 4 * sizeof (zfs_fletcher_sse_t));
}

static void
fletcher_4_sse2_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
{
	uint64_t A, B, C, D;

	/*
	 * The mixing matrix for checksum calculation is:
	 * a = a0 + a1
	 * b = 2b0 + 2b1 - a1
	 * c = 4c0 - b0 + 4c1 -3b1
	 * d = 8d0 - 4c0 + 8d1 - 8c1 + b1;
	 *
	 * c and d are multiplied by 4 and 8, respectively,
	 * before spilling the vectors out to memory.
	 */
	A = ctx->sse[0].v[0] + ctx->sse[0].v[1];
	B = 2 * ctx->sse[1].v[0] + 2 * ctx->sse[1].v[1] - ctx->sse[0].v[1];
	C = 4 * ctx->sse[2].v[0] - ctx->sse[1].v[0] + 4 * ctx->sse[2].v[1] -
	    3 * ctx->sse[1].v[1];
	D = 8 * ctx->sse[3].v[0] - 4 * ctx->sse[2].v[0] + 8 * ctx->sse[3].v[1] -
	    8 * ctx->sse[2].v[1] + ctx->sse[1].v[1];

	ZIO_SET_CHECKSUM(zcp, A, B, C, D);
}

#define	FLETCHER_4_SSE_RESTORE_CTX(ctx)					\
{									\
	asm volatile("movdqu %0, %%xmm0" :: "m" ((ctx)->sse[0]));	\
	asm volatile("movdqu %0, %%xmm1" :: "m" ((ctx)->sse[1]));	\
	asm volatile("movdqu %0, %%xmm2" :: "m" ((ctx)->sse[2]));	\
	asm volatile("movdqu %0, %%xmm3" :: "m" ((ctx)->sse[3]));	\
}

#define	FLETCHER_4_SSE_SAVE_CTX(ctx)					\
{									\
	asm volatile("movdqu %%xmm0, %0" : "=m" ((ctx)->sse[0]));	\
	asm volatile("movdqu %%xmm1, %0" : "=m" ((ctx)->sse[1]));	\
	asm volatile("movdqu %%xmm2, %0" : "=m" ((ctx)->sse[2]));	\
	asm volatile("movdqu %%xmm3, %0" : "=m" ((ctx)->sse[3]));	\
}

static void
fletcher_4_sse2_native(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size)
{
	const uint64_t *ip = buf;
	const uint64_t *ipend = (uint64_t *)((uint8_t *)ip + size);

	kfpu_begin();

	FLETCHER_4_SSE_RESTORE_CTX(ctx);

	asm volatile("pxor %xmm4, %xmm4");

	for (; ip < ipend; ip += 2) {
		asm volatile("movdqu %0, %%xmm5" :: "m"(*ip));
		asm volatile("movdqa %xmm5, %xmm6");
		asm volatile("punpckldq %xmm4, %xmm5");
		asm volatile("punpckhdq %xmm4, %xmm6");
		asm volatile("paddq %xmm5, %xmm0");
		asm volatile("paddq %xmm0, %xmm1");
		asm volatile("paddq %xmm1, %xmm2");
		asm volatile("paddq %xmm2, %xmm3");
		asm volatile("paddq %xmm6, %xmm0");
		asm volatile("paddq %xmm0, %xmm1");
		asm volatile("paddq %xmm1, %xmm2");
		asm volatile("paddq %xmm2, %xmm3");
	}

	FLETCHER_4_SSE_SAVE_CTX(ctx);

	kfpu_end();
}

static void
fletcher_4_sse2_byteswap(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size)
{
	const uint32_t *ip = buf;
	const uint32_t *ipend = (uint32_t *)((uint8_t *)ip + size);

	kfpu_begin();

	FLETCHER_4_SSE_RESTORE_CTX(ctx);

	for (; ip < ipend; ip += 2) {
		uint32_t scratch1 = BSWAP_32(ip[0]);
		uint32_t scratch2 = BSWAP_32(ip[1]);
		asm volatile("movd %0, %%xmm5" :: "r"(scratch1));
		asm volatile("movd %0, %%xmm6" :: "r"(scratch2));
		asm volatile("punpcklqdq %xmm6, %xmm5");
		asm volatile("paddq %xmm5, %xmm0");
		asm volatile("paddq %xmm0, %xmm1");
		asm volatile("paddq %xmm1, %xmm2");
		asm volatile("paddq %xmm2, %xmm3");
	}

	FLETCHER_4_SSE_SAVE_CTX(ctx);

	kfpu_end();
}

static boolean_t fletcher_4_sse2_valid(void)
{
	return (zfs_sse2_available());
}

const fletcher_4_ops_t fletcher_4_sse2_ops = {
	.init_native = fletcher_4_sse2_init,
	.fini_native = fletcher_4_sse2_fini,
	.compute_native = fletcher_4_sse2_native,
	.init_byteswap = fletcher_4_sse2_init,
	.fini_byteswap = fletcher_4_sse2_fini,
	.compute_byteswap = fletcher_4_sse2_byteswap,
	.valid = fletcher_4_sse2_valid,
	.name = "sse2"
};

#endif /* defined(HAVE_SSE2) */

#if defined(HAVE_SSE2) && defined(HAVE_SSSE3)
static void
fletcher_4_ssse3_byteswap(fletcher_4_ctx_t *ctx, const void *buf, uint64_t size)
{
	static const zfs_fletcher_sse_t mask = {
		.v = { 0x0405060700010203, 0x0C0D0E0F08090A0B }
	};

	const uint64_t *ip = buf;
	const uint64_t *ipend = (uint64_t *)((uint8_t *)ip + size);

	kfpu_begin();

	FLETCHER_4_SSE_RESTORE_CTX(ctx);

	asm volatile("movdqu %0, %%xmm7"::"m" (mask));
	asm volatile("pxor %xmm4, %xmm4");

	for (; ip < ipend; ip += 2) {
		asm volatile("movdqu %0, %%xmm5"::"m" (*ip));
		asm volatile("pshufb %xmm7, %xmm5");
		asm volatile("movdqa %xmm5, %xmm6");
		asm volatile("punpckldq %xmm4, %xmm5");
		asm volatile("punpckhdq %xmm4, %xmm6");
		asm volatile("paddq %xmm5, %xmm0");
		asm volatile("paddq %xmm0, %xmm1");
		asm volatile("paddq %xmm1, %xmm2");
		asm volatile("paddq %xmm2, %xmm3");
		asm volatile("paddq %xmm6, %xmm0");
		asm volatile("paddq %xmm0, %xmm1");
		asm volatile("paddq %xmm1, %xmm2");
		asm volatile("paddq %xmm2, %xmm3");
	}

	FLETCHER_4_SSE_SAVE_CTX(ctx);

	kfpu_end();
}

static boolean_t fletcher_4_ssse3_valid(void)
{
	return (zfs_sse2_available() && zfs_ssse3_available());
}

const fletcher_4_ops_t fletcher_4_ssse3_ops = {
	.init_native = fletcher_4_sse2_init,
	.fini_native = fletcher_4_sse2_fini,
	.compute_native = fletcher_4_sse2_native,
	.init_byteswap = fletcher_4_sse2_init,
	.fini_byteswap = fletcher_4_sse2_fini,
	.compute_byteswap = fletcher_4_ssse3_byteswap,
	.valid = fletcher_4_ssse3_valid,
	.name = "ssse3"
};

#endif /* defined(HAVE_SSE2) && defined(HAVE_SSSE3) */
Commit	Line	Data
35a76a03 TS	1	/*
	2	* Implement fast Fletcher4 with SSE2,SSSE3 instructions. (x86)
	3	*
	4	* Use the 128-bit SSE2/SSSE3 SIMD instructions and registers to compute
7f319493	5	* Fletcher4 in two incremental 64-bit parallel accumulator streams,
35a76a03 TS	6	* and then combine the streams to form the final four checksum words.
	7	* This implementation is a derivative of the AVX SIMD implementation by
	8	* James Guilford and Jinshan Xiong from Intel (see zfs_fletcher_intel.c).
	9	*
	10	* Copyright (C) 2016 Tyler J. Stachecki.
	11	*
	12	* Authors:
	13	* Tyler J. Stachecki <stachecki.tyler@gmail.com>
	14	*
	15	* This software is available to you under a choice of one of two
	16	* licenses. You may choose to be licensed under the terms of the GNU
	17	* General Public License (GPL) Version 2, available from the file
	18	* COPYING in the main directory of this source tree, or the
	19	* OpenIB.org BSD license below:
	20	*
	21	* Redistribution and use in source and binary forms, with or
	22	* without modification, are permitted provided that the following
	23	* conditions are met:
	24	*
	25	* - Redistributions of source code must retain the above
	26	* copyright notice, this list of conditions and the following
	27	* disclaimer.
	28	*
	29	* - Redistributions in binary form must reproduce the above
	30	* copyright notice, this list of conditions and the following
	31	* disclaimer in the documentation and/or other materials
	32	* provided with the distribution.
	33	*
	34	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	35	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	36	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	37	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	38	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	39	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	40	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	41	* SOFTWARE.
	42	*/
	43
	44	#if defined(HAVE_SSE2)
	45
	46	#include <linux/simd_x86.h>
	47	#include <sys/spa_checksum.h>
5bf703b8	48	#include <sys/byteorder.h>
93ce2b4c	49	#include <sys/strings.h>
35a76a03	50	#include <zfs_fletcher.h>
35a76a03 TS	51
35a76a03 TS	52	static void
4ea3f864 GM	53	fletcher_4_sse2_init(fletcher_4_ctx_t *ctx)
4ea3f864 GM	54	{
5bf703b8	55	bzero(ctx->sse, 4 * sizeof (zfs_fletcher_sse_t));
35a76a03 TS	56	}
	57
	58	static void
4ea3f864 GM	59	fletcher_4_sse2_fini(fletcher_4_ctx_t ctx, zio_cksum_t zcp)
4ea3f864 GM	60	{
35a76a03 TS	61	uint64_t A, B, C, D;
35a76a03 TS	62
35a76a03 TS	63	/*
	64	* The mixing matrix for checksum calculation is:
	65	* a = a0 + a1
	66	* b = 2b0 + 2b1 - a1
	67	* c = 4c0 - b0 + 4c1 -3b1
	68	* d = 8d0 - 4c0 + 8d1 - 8c1 + b1;
	69	*
	70	* c and d are multiplied by 4 and 8, respectively,
	71	* before spilling the vectors out to memory.
	72	*/
5bf703b8 GN	73	A = ctx->sse[0].v[0] + ctx->sse[0].v[1];
	74	B = 2 * ctx->sse[1].v[0] + 2 * ctx->sse[1].v[1] - ctx->sse[0].v[1];
	75	C = 4 * ctx->sse[2].v[0] - ctx->sse[1].v[0] + 4 * ctx->sse[2].v[1] -
	76	3 * ctx->sse[1].v[1];
	77	D = 8 * ctx->sse[3].v[0] - 4 * ctx->sse[2].v[0] + 8 * ctx->sse[3].v[1] -
	78	8 * ctx->sse[2].v[1] + ctx->sse[1].v[1];
35a76a03 TS	79
	80	ZIO_SET_CHECKSUM(zcp, A, B, C, D);
	81	}
	82
5bf703b8 GN	83	#define FLETCHER_4_SSE_RESTORE_CTX(ctx) \
	84	{ \
	85	asm volatile("movdqu %0, %%xmm0" :: "m" ((ctx)->sse[0])); \
	86	asm volatile("movdqu %0, %%xmm1" :: "m" ((ctx)->sse[1])); \
	87	asm volatile("movdqu %0, %%xmm2" :: "m" ((ctx)->sse[2])); \
	88	asm volatile("movdqu %0, %%xmm3" :: "m" ((ctx)->sse[3])); \
	89	}
	90
	91	#define FLETCHER_4_SSE_SAVE_CTX(ctx) \
	92	{ \
	93	asm volatile("movdqu %%xmm0, %0" : "=m" ((ctx)->sse[0])); \
	94	asm volatile("movdqu %%xmm1, %0" : "=m" ((ctx)->sse[1])); \
	95	asm volatile("movdqu %%xmm2, %0" : "=m" ((ctx)->sse[2])); \
	96	asm volatile("movdqu %%xmm3, %0" : "=m" ((ctx)->sse[3])); \
	97	}
	98
35a76a03	99	static void
5bf703b8	100	fletcher_4_sse2_native(fletcher_4_ctx_t ctx, const void buf, uint64_t size)
35a76a03 TS	101	{
	102	const uint64_t *ip = buf;
	103	const uint64_t ipend = (uint64_t )((uint8_t *)ip + size);
	104
5bf703b8 GN	105	kfpu_begin();
	106
	107	FLETCHER_4_SSE_RESTORE_CTX(ctx);
	108
35a76a03 TS	109	asm volatile("pxor %xmm4, %xmm4");
	110
	111	for (; ip < ipend; ip += 2) {
	112	asm volatile("movdqu %0, %%xmm5" :: "m"(*ip));
	113	asm volatile("movdqa %xmm5, %xmm6");
	114	asm volatile("punpckldq %xmm4, %xmm5");
	115	asm volatile("punpckhdq %xmm4, %xmm6");
	116	asm volatile("paddq %xmm5, %xmm0");
	117	asm volatile("paddq %xmm0, %xmm1");
	118	asm volatile("paddq %xmm1, %xmm2");
	119	asm volatile("paddq %xmm2, %xmm3");
	120	asm volatile("paddq %xmm6, %xmm0");
	121	asm volatile("paddq %xmm0, %xmm1");
	122	asm volatile("paddq %xmm1, %xmm2");
	123	asm volatile("paddq %xmm2, %xmm3");
	124	}
5bf703b8 GN	125
	126	FLETCHER_4_SSE_SAVE_CTX(ctx);
	127
	128	kfpu_end();
35a76a03 TS	129	}
	130
	131	static void
5bf703b8	132	fletcher_4_sse2_byteswap(fletcher_4_ctx_t ctx, const void buf, uint64_t size)
35a76a03 TS	133	{
	134	const uint32_t *ip = buf;
	135	const uint32_t ipend = (uint32_t )((uint8_t *)ip + size);
	136
5bf703b8 GN	137	kfpu_begin();
	138
	139	FLETCHER_4_SSE_RESTORE_CTX(ctx);
35a76a03	140
5bf703b8 GN	141	for (; ip < ipend; ip += 2) {
	142	uint32_t scratch1 = BSWAP_32(ip[0]);
	143	uint32_t scratch2 = BSWAP_32(ip[1]);
	144	asm volatile("movd %0, %%xmm5" :: "r"(scratch1));
	145	asm volatile("movd %0, %%xmm6" :: "r"(scratch2));
35a76a03 TS	146	asm volatile("punpcklqdq %xmm6, %xmm5");
	147	asm volatile("paddq %xmm5, %xmm0");
	148	asm volatile("paddq %xmm0, %xmm1");
	149	asm volatile("paddq %xmm1, %xmm2");
	150	asm volatile("paddq %xmm2, %xmm3");
	151	}
5bf703b8 GN	152
	153	FLETCHER_4_SSE_SAVE_CTX(ctx);
	154
	155	kfpu_end();
35a76a03 TS	156	}
	157
	158	static boolean_t fletcher_4_sse2_valid(void)
	159	{
	160	return (zfs_sse2_available());
	161	}
	162
	163	const fletcher_4_ops_t fletcher_4_sse2_ops = {
fc897b24 GN	164	.init_native = fletcher_4_sse2_init,
	165	.fini_native = fletcher_4_sse2_fini,
	166	.compute_native = fletcher_4_sse2_native,
	167	.init_byteswap = fletcher_4_sse2_init,
	168	.fini_byteswap = fletcher_4_sse2_fini,
35a76a03 TS	169	.compute_byteswap = fletcher_4_sse2_byteswap,
	170	.valid = fletcher_4_sse2_valid,
	171	.name = "sse2"
	172	};
	173
	174	#endif /* defined(HAVE_SSE2) */
	175
	176	#if defined(HAVE_SSE2) && defined(HAVE_SSSE3)
	177	static void
5bf703b8	178	fletcher_4_ssse3_byteswap(fletcher_4_ctx_t ctx, const void buf, uint64_t size)
35a76a03	179	{
5bf703b8	180	static const zfs_fletcher_sse_t mask = {
35a76a03 TS	181	.v = { 0x0405060700010203, 0x0C0D0E0F08090A0B }
	182	};
	183
	184	const uint64_t *ip = buf;
	185	const uint64_t ipend = (uint64_t )((uint8_t *)ip + size);
	186
5bf703b8 GN	187	kfpu_begin();
	188
	189	FLETCHER_4_SSE_RESTORE_CTX(ctx);
	190
3d11ecbd	191	asm volatile("movdqu %0, %%xmm7"::"m" (mask));
35a76a03 TS	192	asm volatile("pxor %xmm4, %xmm4");
	193
	194	for (; ip < ipend; ip += 2) {
	195	asm volatile("movdqu %0, %%xmm5"::"m" (*ip));
	196	asm volatile("pshufb %xmm7, %xmm5");
	197	asm volatile("movdqa %xmm5, %xmm6");
	198	asm volatile("punpckldq %xmm4, %xmm5");
	199	asm volatile("punpckhdq %xmm4, %xmm6");
	200	asm volatile("paddq %xmm5, %xmm0");
	201	asm volatile("paddq %xmm0, %xmm1");
	202	asm volatile("paddq %xmm1, %xmm2");
	203	asm volatile("paddq %xmm2, %xmm3");
	204	asm volatile("paddq %xmm6, %xmm0");
	205	asm volatile("paddq %xmm0, %xmm1");
	206	asm volatile("paddq %xmm1, %xmm2");
	207	asm volatile("paddq %xmm2, %xmm3");
	208	}
5bf703b8 GN	209
	210	FLETCHER_4_SSE_SAVE_CTX(ctx);
	211
	212	kfpu_end();
35a76a03 TS	213	}
	214
	215	static boolean_t fletcher_4_ssse3_valid(void)
	216	{
	217	return (zfs_sse2_available() && zfs_ssse3_available());
	218	}
	219
	220	const fletcher_4_ops_t fletcher_4_ssse3_ops = {
fc897b24 GN	221	.init_native = fletcher_4_sse2_init,
	222	.fini_native = fletcher_4_sse2_fini,
	223	.compute_native = fletcher_4_sse2_native,
	224	.init_byteswap = fletcher_4_sse2_init,
	225	.fini_byteswap = fletcher_4_sse2_fini,
35a76a03 TS	226	.compute_byteswap = fletcher_4_ssse3_byteswap,
	227	.valid = fletcher_4_ssse3_valid,
	228	.name = "ssse3"
	229	};
	230
	231	#endif /* defined(HAVE_SSE2) && defined(HAVE_SSSE3) */