1/*
2 * Copyright (c) 2015, Intel Corporation
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * * Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of Intel Corporation nor the names of its contributors
13 * may be used to endorse or promote products derived from this software
14 * without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** \file
30 * \brief SOM streaming runtime code.
31 *
32 * Code in this file handles storing and loading SOM slot information from
33 * stream state.
34 */
35
36#include "scratch.h"
37#include "som_stream.h"
38#include "rose/rose_internal.h"
39#include "util/multibit.h"
40
41// Sentinel values stored in stream state and used to represent an SOM distance
42// that is too far in the past to be stored in the available space in stream
43// state.
44
45#define SOM_SENTINEL_LARGE (~0ull)
46#define SOM_SENTINEL_MEDIUM (~0u)
47#define SOM_SENTINEL_SMALL ((u16)~0u)
48
49static really_inline
50void storeSomValue(void *stream_som_store, u64a som_value,
51 u64a stream_offset, u8 som_size) {
52 // Special case for sentinel value.
53 if (som_value == SOM_SENTINEL_LARGE) {
54 switch (som_size) {
55 case 2:
56 *(u16 *)stream_som_store = SOM_SENTINEL_SMALL;
57 break;
58 case 4:
59 *(u32 *)stream_som_store = SOM_SENTINEL_MEDIUM;
60 break;
61 case 8:
62 *(u64a *)stream_som_store = SOM_SENTINEL_LARGE;
63 break;
64 default:
65 break;
66 }
67 return;
68 }
69
70 assert(som_value <= stream_offset);
71 u64a rel_offset = stream_offset - som_value;
72 DEBUG_PRINTF("rel_offset=%llu\n", rel_offset);
73
74 switch (som_size) {
75 case 2:
76 rel_offset = MIN(rel_offset, SOM_SENTINEL_SMALL);
77 assert(ISALIGNED_N(stream_som_store, alignof(u16)));
78 *(u16 *)stream_som_store = rel_offset;
79 break;
80 case 4:
81 rel_offset = MIN(rel_offset, SOM_SENTINEL_MEDIUM);
82 assert(ISALIGNED_N(stream_som_store, alignof(u32)));
83 *(u32 *)stream_som_store = rel_offset;
84 break;
85 case 8:
86 assert(ISALIGNED_N(stream_som_store, alignof(u64a)));
87 *(u64a *)stream_som_store = rel_offset;
88 break;
89 default:
90 assert(0);
91 break;
92 }
93}
94
95void storeSomToStream(struct hs_scratch *scratch, const u64a offset) {
96 assert(scratch);
97 DEBUG_PRINTF("stream offset %llu\n", offset);
98
99 struct core_info *ci = &scratch->core_info;
100 const struct RoseEngine *rose = ci->rose;
101
102 const u32 som_store_count = rose->somLocationCount;
103 assert(som_store_count); // Caller should ensure that we have work to do.
104
105 u8 *som_store_valid = (u8 *)ci->state + rose->stateOffsets.somValid;
106 char *stream_som_store = ci->state + rose->stateOffsets.somLocation;
107 const u64a *som_store = scratch->som_store;
108 const u8 som_size = rose->somHorizon;
109
110 for (u32 i = mmbit_iterate(som_store_valid, som_store_count, MMB_INVALID);
111 i != MMB_INVALID;
112 i = mmbit_iterate(som_store_valid, som_store_count, i)) {
113 DEBUG_PRINTF("storing %llu in %u\n", som_store[i], i);
114 storeSomValue(stream_som_store + (i * som_size), som_store[i],
115 offset, som_size);
116 }
117}
118
119static really_inline
120u64a loadSomValue(const void *stream_som_store, u64a stream_offset,
121 u8 som_size) {
122 u64a rel_offset;
123 switch (som_size) {
124 case 2:
125 assert(ISALIGNED_N(stream_som_store, alignof(u16)));
126 rel_offset = *(const u16 *)stream_som_store;
127 if (rel_offset == SOM_SENTINEL_SMALL) {
128 return SOM_SENTINEL_LARGE;
129 }
130 break;
131 case 4:
132 assert(ISALIGNED_N(stream_som_store, alignof(u32)));
133 rel_offset = *(const u32 *)stream_som_store;
134 if (rel_offset == SOM_SENTINEL_MEDIUM) {
135 return SOM_SENTINEL_LARGE;
136 }
137 break;
138 case 8:
139 assert(ISALIGNED_N(stream_som_store, alignof(u64a)));
140 rel_offset = *(const u64a *)stream_som_store;
141 break;
142 default:
143 assert(0);
144 rel_offset = 0;
145 break;
146 }
147
148 DEBUG_PRINTF("rel_offset=%llu\n", rel_offset);
149 return stream_offset - rel_offset;
150}
151
152void loadSomFromStream(struct hs_scratch *scratch, const u64a offset) {
153 assert(scratch);
154 DEBUG_PRINTF("stream offset %llu\n", offset);
155
156 struct core_info *ci = &scratch->core_info;
157 const struct RoseEngine *rose = ci->rose;
158
159 const u32 som_store_count = rose->somLocationCount;
160 assert(som_store_count); // Caller should ensure that we have work to do.
161
162 const u8 *som_store_valid = (u8 *)ci->state + rose->stateOffsets.somValid;
163 const char *stream_som_store = ci->state + rose->stateOffsets.somLocation;
164 u64a *som_store = scratch->som_store;
165 const u8 som_size = rose->somHorizon;
166
167 for (u32 i = mmbit_iterate(som_store_valid, som_store_count, MMB_INVALID);
168 i != MMB_INVALID;
169 i = mmbit_iterate(som_store_valid, som_store_count, i)) {
170 som_store[i] = loadSomValue(stream_som_store + (i*som_size), offset,
171 som_size);
172 DEBUG_PRINTF("loaded %llu from %u\n", som_store[i], i);
173 }
174}
175