Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* -*- linux-c -*- ------------------------------------------------------- * |
| 2 | * |
| 3 | * Copyright 2002 H. Peter Anvin - All Rights Reserved |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation, Inc., 53 Temple Place Ste 330, |
Atsushi SAKAI | 93ed05e | 2009-03-31 14:57:37 +1100 | [diff] [blame] | 8 | * Boston MA 02111-1307, USA; either version 2 of the License, or |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * (at your option) any later version; incorporated herein by reference. |
| 10 | * |
| 11 | * ----------------------------------------------------------------------- */ |
| 12 | |
| 13 | /* |
NeilBrown | a8e026c | 2010-08-12 06:44:54 +1000 | [diff] [blame] | 14 | * raid6/algos.c |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | * |
| 16 | * Algorithm list and algorithm selection for RAID-6 |
| 17 | */ |
| 18 | |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 19 | #include <linux/raid/pq.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #ifndef __KERNEL__ |
| 21 | #include <sys/mman.h> |
H. Peter Anvin | d7e70ba | 2005-09-16 19:27:29 -0700 | [diff] [blame] | 22 | #include <stdio.h> |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 23 | #else |
Jim Kukunas | f674ef7 | 2012-05-22 13:54:16 +1000 | [diff] [blame] | 24 | #include <linux/module.h> |
NeilBrown | d5302fe | 2010-08-12 06:38:24 +1000 | [diff] [blame] | 25 | #include <linux/gfp.h> |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 26 | #if !RAID6_USE_EMPTY_ZERO_PAGE |
| 27 | /* In .bss so it's zeroed */ |
| 28 | const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256))); |
| 29 | EXPORT_SYMBOL(raid6_empty_zero_page); |
| 30 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | #endif |
| 32 | |
| 33 | struct raid6_calls raid6_call; |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 34 | EXPORT_SYMBOL_GPL(raid6_call); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | const struct raid6_calls * const raid6_algos[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | #if defined(__ia64__) |
| 38 | &raid6_intx16, |
| 39 | &raid6_intx32, |
| 40 | #endif |
Al Viro | ca5cd87 | 2007-10-29 04:31:16 +0000 | [diff] [blame] | 41 | #if defined(__i386__) && !defined(__arch_um__) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | &raid6_mmxx1, |
| 43 | &raid6_mmxx2, |
| 44 | &raid6_sse1x1, |
| 45 | &raid6_sse1x2, |
| 46 | &raid6_sse2x1, |
| 47 | &raid6_sse2x2, |
Yuanhan Liu | 2c93584 | 2012-11-30 13:10:39 -0800 | [diff] [blame] | 48 | #ifdef CONFIG_AS_AVX2 |
| 49 | &raid6_avx2x1, |
| 50 | &raid6_avx2x2, |
| 51 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | #endif |
Al Viro | ca5cd87 | 2007-10-29 04:31:16 +0000 | [diff] [blame] | 53 | #if defined(__x86_64__) && !defined(__arch_um__) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | &raid6_sse2x1, |
| 55 | &raid6_sse2x2, |
| 56 | &raid6_sse2x4, |
Yuanhan Liu | 2c93584 | 2012-11-30 13:10:39 -0800 | [diff] [blame] | 57 | #ifdef CONFIG_AS_AVX2 |
| 58 | &raid6_avx2x1, |
| 59 | &raid6_avx2x2, |
| 60 | &raid6_avx2x4, |
| 61 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | #endif |
| 63 | #ifdef CONFIG_ALTIVEC |
| 64 | &raid6_altivec1, |
| 65 | &raid6_altivec2, |
| 66 | &raid6_altivec4, |
| 67 | &raid6_altivec8, |
| 68 | #endif |
Ken Steele | ae77cbc | 2013-08-07 12:39:56 -0400 | [diff] [blame] | 69 | #if defined(CONFIG_TILEGX) |
| 70 | &raid6_tilegx8, |
| 71 | #endif |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 72 | &raid6_intx1, |
| 73 | &raid6_intx2, |
| 74 | &raid6_intx4, |
| 75 | &raid6_intx8, |
Ard Biesheuvel | 7d11965 | 2013-05-16 17:20:32 +0200 | [diff] [blame] | 76 | #ifdef CONFIG_KERNEL_MODE_NEON |
| 77 | &raid6_neonx1, |
| 78 | &raid6_neonx2, |
| 79 | &raid6_neonx4, |
| 80 | &raid6_neonx8, |
| 81 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | NULL |
| 83 | }; |
| 84 | |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 85 | void (*raid6_2data_recov)(int, size_t, int, int, void **); |
| 86 | EXPORT_SYMBOL_GPL(raid6_2data_recov); |
| 87 | |
| 88 | void (*raid6_datap_recov)(int, size_t, int, void **); |
| 89 | EXPORT_SYMBOL_GPL(raid6_datap_recov); |
| 90 | |
| 91 | const struct raid6_recov_calls *const raid6_recov_algos[] = { |
| 92 | #if (defined(__i386__) || defined(__x86_64__)) && !defined(__arch_um__) |
Jim Kukunas | 7056741 | 2012-11-08 13:47:44 -0800 | [diff] [blame] | 93 | #ifdef CONFIG_AS_AVX2 |
| 94 | &raid6_recov_avx2, |
| 95 | #endif |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 96 | &raid6_recov_ssse3, |
| 97 | #endif |
| 98 | &raid6_recov_intx1, |
| 99 | NULL |
| 100 | }; |
| 101 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | #ifdef __KERNEL__ |
| 103 | #define RAID6_TIME_JIFFIES_LG2 4 |
| 104 | #else |
| 105 | /* Need more time to be stable in userspace */ |
| 106 | #define RAID6_TIME_JIFFIES_LG2 9 |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 107 | #define time_before(x, y) ((x) < (y)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | #endif |
| 109 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 110 | static inline const struct raid6_recov_calls *raid6_choose_recov(void) |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 111 | { |
| 112 | const struct raid6_recov_calls *const *algo; |
| 113 | const struct raid6_recov_calls *best; |
| 114 | |
| 115 | for (best = NULL, algo = raid6_recov_algos; *algo; algo++) |
| 116 | if (!best || (*algo)->priority > best->priority) |
| 117 | if (!(*algo)->valid || (*algo)->valid()) |
| 118 | best = *algo; |
| 119 | |
| 120 | if (best) { |
| 121 | raid6_2data_recov = best->data2; |
| 122 | raid6_datap_recov = best->datap; |
| 123 | |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 124 | pr_info("raid6: using %s recovery algorithm\n", best->name); |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 125 | } else |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 126 | pr_err("raid6: Yikes! No recovery algorithm found!\n"); |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 127 | |
| 128 | return best; |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 129 | } |
| 130 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 131 | static inline const struct raid6_calls *raid6_choose_gen( |
| 132 | void *(*const dptrs)[(65536/PAGE_SIZE)+2], const int disks) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | { |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 134 | unsigned long perf, bestperf, j0, j1; |
| 135 | const struct raid6_calls *const *algo; |
| 136 | const struct raid6_calls *best; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 138 | for (bestperf = 0, best = NULL, algo = raid6_algos; *algo; algo++) { |
| 139 | if (!best || (*algo)->prefer >= best->prefer) { |
| 140 | if ((*algo)->valid && !(*algo)->valid()) |
| 141 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | perf = 0; |
| 144 | |
| 145 | preempt_disable(); |
| 146 | j0 = jiffies; |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 147 | while ((j1 = jiffies) == j0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | cpu_relax(); |
Julia Lawall | 62b0559 | 2008-04-28 02:15:56 -0700 | [diff] [blame] | 149 | while (time_before(jiffies, |
| 150 | j1 + (1<<RAID6_TIME_JIFFIES_LG2))) { |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 151 | (*algo)->gen_syndrome(disks, PAGE_SIZE, *dptrs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | perf++; |
| 153 | } |
| 154 | preempt_enable(); |
| 155 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 156 | if (perf > bestperf) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | bestperf = perf; |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 158 | best = *algo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | } |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 160 | pr_info("raid6: %-8s %5ld MB/s\n", (*algo)->name, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 161 | (perf*HZ) >> (20-16+RAID6_TIME_JIFFIES_LG2)); |
| 162 | } |
| 163 | } |
| 164 | |
Adrian Bunk | a5d6839 | 2006-06-23 02:05:59 -0700 | [diff] [blame] | 165 | if (best) { |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 166 | pr_info("raid6: using algorithm %s (%ld MB/s)\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | best->name, |
| 168 | (bestperf*HZ) >> (20-16+RAID6_TIME_JIFFIES_LG2)); |
Adrian Bunk | a5d6839 | 2006-06-23 02:05:59 -0700 | [diff] [blame] | 169 | raid6_call = *best; |
| 170 | } else |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 171 | pr_err("raid6: Yikes! No algorithm found!\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 173 | return best; |
| 174 | } |
| 175 | |
| 176 | |
| 177 | /* Try to pick the best algorithm */ |
| 178 | /* This code uses the gfmul table as convenient data set to abuse */ |
| 179 | |
| 180 | int __init raid6_select_algo(void) |
| 181 | { |
| 182 | const int disks = (65536/PAGE_SIZE)+2; |
| 183 | |
| 184 | const struct raid6_calls *gen_best; |
| 185 | const struct raid6_recov_calls *rec_best; |
| 186 | char *syndromes; |
| 187 | void *dptrs[(65536/PAGE_SIZE)+2]; |
| 188 | int i; |
| 189 | |
| 190 | for (i = 0; i < disks-2; i++) |
| 191 | dptrs[i] = ((char *)raid6_gfmul) + PAGE_SIZE*i; |
| 192 | |
| 193 | /* Normal code - use a 2-page allocation to avoid D$ conflict */ |
| 194 | syndromes = (void *) __get_free_pages(GFP_KERNEL, 1); |
| 195 | |
| 196 | if (!syndromes) { |
Anton Blanchard | b395f75 | 2014-10-13 23:03:16 +1100 | [diff] [blame] | 197 | pr_err("raid6: Yikes! No memory available.\n"); |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 198 | return -ENOMEM; |
| 199 | } |
| 200 | |
| 201 | dptrs[disks-2] = syndromes; |
| 202 | dptrs[disks-1] = syndromes + PAGE_SIZE; |
| 203 | |
| 204 | /* select raid gen_syndrome function */ |
| 205 | gen_best = raid6_choose_gen(&dptrs, disks); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 207 | /* select raid recover functions */ |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 208 | rec_best = raid6_choose_recov(); |
Jim Kukunas | 048a8b8 | 2012-05-22 13:54:18 +1000 | [diff] [blame] | 209 | |
Jim Kukunas | 96e6770 | 2012-05-22 13:54:24 +1000 | [diff] [blame] | 210 | free_pages((unsigned long)syndromes, 1); |
| 211 | |
| 212 | return gen_best && rec_best ? 0 : -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | } |
Dan Williams | f701d58 | 2009-03-31 15:09:39 +1100 | [diff] [blame] | 214 | |
| 215 | static void raid6_exit(void) |
| 216 | { |
| 217 | do { } while (0); |
| 218 | } |
| 219 | |
| 220 | subsys_initcall(raid6_select_algo); |
| 221 | module_exit(raid6_exit); |
| 222 | MODULE_LICENSE("GPL"); |
NeilBrown | 0efb9e6 | 2009-12-14 12:49:58 +1100 | [diff] [blame] | 223 | MODULE_DESCRIPTION("RAID6 Q-syndrome calculations"); |