include/asm-x86_64/xor.h

   1 /*
   2  * include/asm-x86_64/xor.h
   3  *
   4  * Optimized RAID-5 checksumming functions for MMX and SSE.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * (for example /usr/src/linux/COPYING); if not, write to the Free
  13  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  14  */
  15
  16
  17 /*
  18  * Cache avoiding checksumming functions utilizing KNI instructions
  19  * Copyright (C) 1999 Zach Brown (with obvious credit due Ingo)
  20  */
  21
  22 /*
  23  * Based on
  24  * High-speed RAID5 checksumming functions utilizing SSE instructions.
  25  * Copyright (C) 1998 Ingo Molnar.
  26  */
  27
  28 /*
  29  * x86-64 changes / gcc fixes from Andi Kleen.
  30  * Copyright 2002 Andi Kleen, SuSE Labs.
  31  *
  32  * This hasn't been optimized for the hammer yet, but there are likely
  33  * no advantages to be gotten from x86-64 here anyways.
  34  */
  35
  36 typedef struct { unsigned long a,b; } __attribute__((aligned(16))) xmm_store_t;
  37
  38 /* Doesn't use gcc to save the XMM registers, because there is no easy way to
  39    tell it to do a clts before the register saving. */
  40 #define XMMS_SAVE do {                          \
  41         preempt_disable();                      \
  42         asm volatile (                          \
  43                 "movq %%cr0,%0          ;\n\t"  \
  44                 "clts                   ;\n\t"  \
  45                 "movups %%xmm0,(%1)     ;\n\t"  \
  46                 "movups %%xmm1,0x10(%1) ;\n\t"  \
  47                 "movups %%xmm2,0x20(%1) ;\n\t"  \
  48                 "movups %%xmm3,0x30(%1) ;\n\t"  \
  49                 : "=&r" (cr0)                   \
  50                 : "r" (xmm_save)                \
  51                 : "memory");                    \
  52 } while(0)
  53
  54 #define XMMS_RESTORE do {                       \
  55         asm volatile (                          \
  56                 "sfence                 ;\n\t"  \
  57                 "movups (%1),%%xmm0     ;\n\t"  \
  58                 "movups 0x10(%1),%%xmm1 ;\n\t"  \
  59                 "movups 0x20(%1),%%xmm2 ;\n\t"  \
  60                 "movups 0x30(%1),%%xmm3 ;\n\t"  \
  61                 "movq   %0,%%cr0        ;\n\t"  \
  62                 :                               \
  63                 : "r" (cr0), "r" (xmm_save)     \
  64                 : "memory");                    \
  65         preempt_enable();                       \
  66 } while(0)
  67
  68 #define OFFS(x)         "16*("#x")"
  69 #define PF_OFFS(x)      "256+16*("#x")"
  70 #define PF0(x)          "       prefetchnta "PF_OFFS(x)"(%[p1])         ;\n"
  71 #define LD(x,y)         "       movaps   "OFFS(x)"(%[p1]), %%xmm"#y"    ;\n"
  72 #define ST(x,y)         "       movaps %%xmm"#y",   "OFFS(x)"(%[p1])    ;\n"
  73 #define PF1(x)          "       prefetchnta "PF_OFFS(x)"(%[p2])         ;\n"
  74 #define PF2(x)          "       prefetchnta "PF_OFFS(x)"(%[p3])         ;\n"
  75 #define PF3(x)          "       prefetchnta "PF_OFFS(x)"(%[p4])         ;\n"
  76 #define PF4(x)          "       prefetchnta "PF_OFFS(x)"(%[p5])         ;\n"
  77 #define PF5(x)          "       prefetchnta "PF_OFFS(x)"(%[p6])         ;\n"
  78 #define XO1(x,y)        "       xorps   "OFFS(x)"(%[p2]), %%xmm"#y"     ;\n"
  79 #define XO2(x,y)        "       xorps   "OFFS(x)"(%[p3]), %%xmm"#y"     ;\n"
  80 #define XO3(x,y)        "       xorps   "OFFS(x)"(%[p4]), %%xmm"#y"     ;\n"
  81 #define XO4(x,y)        "       xorps   "OFFS(x)"(%[p5]), %%xmm"#y"     ;\n"
  82 #define XO5(x,y)        "       xorps   "OFFS(x)"(%[p6]), %%xmm"#y"     ;\n"
  83
  84
  85 static void
  86 xor_sse_2(unsigned long bytes, unsigned long *p1, unsigned long *p2)
  87 {
  88         unsigned int lines = bytes >> 8;
  89         unsigned long cr0;
  90         xmm_store_t xmm_save[4];
  91
  92         XMMS_SAVE;
  93
  94         asm volatile (
  95 #undef BLOCK
  96 #define BLOCK(i) \
  97                 LD(i,0)                                 \
  98                         LD(i+1,1)                       \
  99                 PF1(i)                                  \
 100                                 PF1(i+2)                \
 101                                 LD(i+2,2)               \
 102                                         LD(i+3,3)       \
 103                 PF0(i+4)                                \
 104                                 PF0(i+6)                \
 105                 XO1(i,0)                                \
 106                         XO1(i+1,1)                      \
 107                                 XO1(i+2,2)              \
 108                                         XO1(i+3,3)      \
 109                 ST(i,0)                                 \
 110                         ST(i+1,1)                       \
 111                                 ST(i+2,2)               \
 112                                         ST(i+3,3)       \
 113
 114
 115                 PF0(0)
 116                                 PF0(2)
 117
 118         " .align 32                     ;\n"
 119         " 1:                            ;\n"
 120
 121                 BLOCK(0)
 122                 BLOCK(4)
 123                 BLOCK(8)
 124                 BLOCK(12)
 125
 126         "       addq %[inc], %[p1]           ;\n"
 127         "       addq %[inc], %[p2]           ;\n"
 128                 "               decl %[cnt] ; jnz 1b"
 129         : [p1] "+r" (p1), [p2] "+r" (p2), [cnt] "+r" (lines)
 130         : [inc] "r" (256UL)
 131         : "memory");
 132
 133         XMMS_RESTORE;
 134 }
 135
 136 static void
 137 xor_sse_3(unsigned long bytes, unsigned long *p1, unsigned long *p2,
 138           unsigned long *p3)
 139 {
 140         unsigned int lines = bytes >> 8;
 141         xmm_store_t xmm_save[4];
 142         unsigned long cr0;
 143
 144         XMMS_SAVE;
 145
 146         __asm__ __volatile__ (
 147 #undef BLOCK
 148 #define BLOCK(i) \
 149                 PF1(i)                                  \
 150                                 PF1(i+2)                \
 151                 LD(i,0)                                 \
 152                         LD(i+1,1)                       \
 153                                 LD(i+2,2)               \
 154                                         LD(i+3,3)       \
 155                 PF2(i)                                  \
 156                                 PF2(i+2)                \
 157                 PF0(i+4)                                \
 158                                 PF0(i+6)                \
 159                 XO1(i,0)                                \
 160                         XO1(i+1,1)                      \
 161                                 XO1(i+2,2)              \
 162                                         XO1(i+3,3)      \
 163                 XO2(i,0)                                \
 164                         XO2(i+1,1)                      \
 165                                 XO2(i+2,2)              \
 166                                         XO2(i+3,3)      \
 167                 ST(i,0)                                 \
 168                         ST(i+1,1)                       \
 169                                 ST(i+2,2)               \
 170                                         ST(i+3,3)       \
 171
 172
 173                 PF0(0)
 174                                 PF0(2)
 175
 176         " .align 32                     ;\n"
 177         " 1:                            ;\n"
 178
 179                 BLOCK(0)
 180                 BLOCK(4)
 181                 BLOCK(8)
 182                 BLOCK(12)
 183
 184         "       addq %[inc], %[p1]           ;\n"
 185         "       addq %[inc], %[p2]          ;\n"
 186         "       addq %[inc], %[p3]           ;\n"
 187                 "               decl %[cnt] ; jnz 1b"
 188         : [cnt] "+r" (lines),
 189           [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3)
 190         : [inc] "r" (256UL)
 191         : "memory");
 192         XMMS_RESTORE;
 193 }
 194
 195 static void
 196 xor_sse_4(unsigned long bytes, unsigned long *p1, unsigned long *p2,
 197           unsigned long *p3, unsigned long *p4)
 198 {
 199         unsigned int lines = bytes >> 8;
 200         xmm_store_t xmm_save[4];
 201         unsigned long cr0;
 202
 203         XMMS_SAVE;
 204
 205         __asm__ __volatile__ (
 206 #undef BLOCK
 207 #define BLOCK(i) \
 208                 PF1(i)                                  \
 209                                 PF1(i+2)                \
 210                 LD(i,0)                                 \
 211                         LD(i+1,1)                       \
 212                                 LD(i+2,2)               \
 213                                         LD(i+3,3)       \
 214                 PF2(i)                                  \
 215                                 PF2(i+2)                \
 216                 XO1(i,0)                                \
 217                         XO1(i+1,1)                      \
 218                                 XO1(i+2,2)              \
 219                                         XO1(i+3,3)      \
 220                 PF3(i)                                  \
 221                                 PF3(i+2)                \
 222                 PF0(i+4)                                \
 223                                 PF0(i+6)                \
 224                 XO2(i,0)                                \
 225                         XO2(i+1,1)                      \
 226                                 XO2(i+2,2)              \
 227                                         XO2(i+3,3)      \
 228                 XO3(i,0)                                \
 229                         XO3(i+1,1)                      \
 230                                 XO3(i+2,2)              \
 231                                         XO3(i+3,3)      \
 232                 ST(i,0)                                 \
 233                         ST(i+1,1)                       \
 234                                 ST(i+2,2)               \
 235                                         ST(i+3,3)       \
 236
 237
 238                 PF0(0)
 239                                 PF0(2)
 240
 241         " .align 32                     ;\n"
 242         " 1:                            ;\n"
 243
 244                 BLOCK(0)
 245                 BLOCK(4)
 246                 BLOCK(8)
 247                 BLOCK(12)
 248
 249         "       addq %[inc], %[p1]           ;\n"
 250         "       addq %[inc], %[p2]           ;\n"
 251         "       addq %[inc], %[p3]           ;\n"
 252         "       addq %[inc], %[p4]           ;\n"
 253         "       decl %[cnt] ; jnz 1b"
 254         : [cnt] "+c" (lines),
 255           [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3), [p4] "+r" (p4)
 256         : [inc] "r" (256UL)
 257         : "memory" );
 258
 259         XMMS_RESTORE;
 260 }
 261
 262 static void
 263 xor_sse_5(unsigned long bytes, unsigned long *p1, unsigned long *p2,
 264           unsigned long *p3, unsigned long *p4, unsigned long *p5)
 265 {
 266         unsigned int lines = bytes >> 8;
 267         xmm_store_t xmm_save[4];
 268         unsigned long cr0;
 269
 270         XMMS_SAVE;
 271
 272         __asm__ __volatile__ (
 273 #undef BLOCK
 274 #define BLOCK(i) \
 275                 PF1(i)                                  \
 276                                 PF1(i+2)                \
 277                 LD(i,0)                                 \
 278                         LD(i+1,1)                       \
 279                                 LD(i+2,2)               \
 280                                         LD(i+3,3)       \
 281                 PF2(i)                                  \
 282                                 PF2(i+2)                \
 283                 XO1(i,0)                                \
 284                         XO1(i+1,1)                      \
 285                                 XO1(i+2,2)              \
 286                                         XO1(i+3,3)      \
 287                 PF3(i)                                  \
 288                                 PF3(i+2)                \
 289                 XO2(i,0)                                \
 290                         XO2(i+1,1)                      \
 291                                 XO2(i+2,2)              \
 292                                         XO2(i+3,3)      \
 293                 PF4(i)                                  \
 294                                 PF4(i+2)                \
 295                 PF0(i+4)                                \
 296                                 PF0(i+6)                \
 297                 XO3(i,0)                                \
 298                         XO3(i+1,1)                      \
 299                                 XO3(i+2,2)              \
 300                                         XO3(i+3,3)      \
 301                 XO4(i,0)                                \
 302                         XO4(i+1,1)                      \
 303                                 XO4(i+2,2)              \
 304                                         XO4(i+3,3)      \
 305                 ST(i,0)                                 \
 306                         ST(i+1,1)                       \
 307                                 ST(i+2,2)               \
 308                                         ST(i+3,3)       \
 309
 310
 311                 PF0(0)
 312                                 PF0(2)
 313
 314         " .align 32                     ;\n"
 315         " 1:                            ;\n"
 316
 317                 BLOCK(0)
 318                 BLOCK(4)
 319                 BLOCK(8)
 320                 BLOCK(12)
 321
 322         "       addq %[inc], %[p1]           ;\n"
 323         "       addq %[inc], %[p2]           ;\n"
 324         "       addq %[inc], %[p3]           ;\n"
 325         "       addq %[inc], %[p4]           ;\n"
 326         "       addq %[inc], %[p5]           ;\n"
 327         "       decl %[cnt] ; jnz 1b"
 328         : [cnt] "+c" (lines),
 329           [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3), [p4] "+r" (p4),
 330           [p5] "+r" (p5)
 331         : [inc] "r" (256UL)
 332         : "memory");
 333
 334         XMMS_RESTORE;
 335 }
 336
 337 static struct xor_block_template xor_block_sse = {
 338         .name = "generic_sse",
 339         .do_2 = xor_sse_2,
 340         .do_3 = xor_sse_3,
 341         .do_4 = xor_sse_4,
 342         .do_5 = xor_sse_5,
 343 };
 344
 345 #undef XOR_TRY_TEMPLATES
 346 #define XOR_TRY_TEMPLATES                               \
 347         do {                                            \
 348                 xor_speed(&xor_block_sse);      \
 349         } while (0)
 350
 351 /* We force the use of the SSE xor block because it can write around L2.
 352    We may also be able to load into the L1 only depending on how the cpu
 353    deals with a load to a line that is being prefetched.  */
 354 #define XOR_SELECT_TEMPLATE(FASTEST) (&xor_block_sse)