1 //===----------- api.cpp - Target independent OpenMP target RTL -----------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // Implementation of OpenMP API interface functions. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include <omptarget.h> 14 15 #include "device.h" 16 #include "private.h" 17 #include "rtl.h" 18 19 #include <climits> 20 #include <cstring> 21 #include <cstdlib> 22 23 EXTERN int omp_get_num_devices(void) { 24 RTLsMtx->lock(); 25 size_t Devices_size = Devices.size(); 26 RTLsMtx->unlock(); 27 28 DP("Call to omp_get_num_devices returning %zd\n", Devices_size); 29 30 return Devices_size; 31 } 32 33 EXTERN int omp_get_initial_device(void) { 34 DP("Call to omp_get_initial_device returning %d\n", HOST_DEVICE); 35 return HOST_DEVICE; 36 } 37 38 EXTERN void *omp_target_alloc(size_t size, int device_num) { 39 DP("Call to omp_target_alloc for device %d requesting %zu bytes\n", 40 device_num, size); 41 42 if (size <= 0) { 43 DP("Call to omp_target_alloc with non-positive length\n"); 44 return NULL; 45 } 46 47 void *rc = NULL; 48 49 if (device_num == omp_get_initial_device()) { 50 rc = malloc(size); 51 DP("omp_target_alloc returns host ptr " DPxMOD "\n", DPxPTR(rc)); 52 return rc; 53 } 54 55 if (!device_is_ready(device_num)) { 56 DP("omp_target_alloc returns NULL ptr\n"); 57 return NULL; 58 } 59 60 rc = Devices[device_num].allocData(size); 61 DP("omp_target_alloc returns device ptr " DPxMOD "\n", DPxPTR(rc)); 62 return rc; 63 } 64 65 EXTERN void omp_target_free(void *device_ptr, int device_num) { 66 DP("Call to omp_target_free for device %d and address " DPxMOD "\n", 67 device_num, DPxPTR(device_ptr)); 68 69 if (!device_ptr) { 70 DP("Call to omp_target_free with NULL ptr\n"); 71 return; 72 } 73 74 if (device_num == omp_get_initial_device()) { 75 free(device_ptr); 76 DP("omp_target_free deallocated host ptr\n"); 77 return; 78 } 79 80 if (!device_is_ready(device_num)) { 81 DP("omp_target_free returns, nothing to do\n"); 82 return; 83 } 84 85 Devices[device_num].deleteData(device_ptr); 86 DP("omp_target_free deallocated device ptr\n"); 87 } 88 89 EXTERN int omp_target_is_present(void *ptr, int device_num) { 90 DP("Call to omp_target_is_present for device %d and address " DPxMOD "\n", 91 device_num, DPxPTR(ptr)); 92 93 if (!ptr) { 94 DP("Call to omp_target_is_present with NULL ptr, returning false\n"); 95 return false; 96 } 97 98 if (device_num == omp_get_initial_device()) { 99 DP("Call to omp_target_is_present on host, returning true\n"); 100 return true; 101 } 102 103 RTLsMtx->lock(); 104 size_t Devices_size = Devices.size(); 105 RTLsMtx->unlock(); 106 if (Devices_size <= (size_t)device_num) { 107 DP("Call to omp_target_is_present with invalid device ID, returning " 108 "false\n"); 109 return false; 110 } 111 112 DeviceTy& Device = Devices[device_num]; 113 bool IsLast; // not used 114 bool IsHostPtr; 115 void *TgtPtr = Device.getTgtPtrBegin(ptr, 0, IsLast, false, IsHostPtr); 116 int rc = (TgtPtr != NULL); 117 // Under unified memory the host pointer can be returned by the 118 // getTgtPtrBegin() function which means that there is no device 119 // corresponding point for ptr. This function should return false 120 // in that situation. 121 if (RTLs->RequiresFlags & OMP_REQ_UNIFIED_SHARED_MEMORY) 122 rc = !IsHostPtr; 123 DP("Call to omp_target_is_present returns %d\n", rc); 124 return rc; 125 } 126 127 EXTERN int omp_target_memcpy(void *dst, void *src, size_t length, 128 size_t dst_offset, size_t src_offset, int dst_device, int src_device) { 129 DP("Call to omp_target_memcpy, dst device %d, src device %d, " 130 "dst addr " DPxMOD ", src addr " DPxMOD ", dst offset %zu, " 131 "src offset %zu, length %zu\n", dst_device, src_device, DPxPTR(dst), 132 DPxPTR(src), dst_offset, src_offset, length); 133 134 if (!dst || !src || length <= 0) { 135 DP("Call to omp_target_memcpy with invalid arguments\n"); 136 return OFFLOAD_FAIL; 137 } 138 139 if (src_device != omp_get_initial_device() && !device_is_ready(src_device)) { 140 DP("omp_target_memcpy returns OFFLOAD_FAIL\n"); 141 return OFFLOAD_FAIL; 142 } 143 144 if (dst_device != omp_get_initial_device() && !device_is_ready(dst_device)) { 145 DP("omp_target_memcpy returns OFFLOAD_FAIL\n"); 146 return OFFLOAD_FAIL; 147 } 148 149 int rc = OFFLOAD_SUCCESS; 150 void *srcAddr = (char *)src + src_offset; 151 void *dstAddr = (char *)dst + dst_offset; 152 153 if (src_device == omp_get_initial_device() && 154 dst_device == omp_get_initial_device()) { 155 DP("copy from host to host\n"); 156 const void *p = memcpy(dstAddr, srcAddr, length); 157 if (p == NULL) 158 rc = OFFLOAD_FAIL; 159 } else if (src_device == omp_get_initial_device()) { 160 DP("copy from host to device\n"); 161 DeviceTy& DstDev = Devices[dst_device]; 162 rc = DstDev.submitData(dstAddr, srcAddr, length, nullptr); 163 } else if (dst_device == omp_get_initial_device()) { 164 DP("copy from device to host\n"); 165 DeviceTy& SrcDev = Devices[src_device]; 166 rc = SrcDev.retrieveData(dstAddr, srcAddr, length, nullptr); 167 } else { 168 DP("copy from device to device\n"); 169 DeviceTy &SrcDev = Devices[src_device]; 170 DeviceTy &DstDev = Devices[dst_device]; 171 // First try to use D2D memcpy which is more efficient. If fails, fall back 172 // to unefficient way. 173 if (SrcDev.isDataExchangable(DstDev)) { 174 rc = SrcDev.data_exchange(srcAddr, DstDev, dstAddr, length, nullptr); 175 if (rc == OFFLOAD_SUCCESS) 176 return OFFLOAD_SUCCESS; 177 } 178 179 void *buffer = malloc(length); 180 rc = SrcDev.retrieveData(buffer, srcAddr, length, nullptr); 181 if (rc == OFFLOAD_SUCCESS) 182 rc = DstDev.submitData(dstAddr, buffer, length, nullptr); 183 free(buffer); 184 } 185 186 DP("omp_target_memcpy returns %d\n", rc); 187 return rc; 188 } 189 190 EXTERN int omp_target_memcpy_rect(void *dst, void *src, size_t element_size, 191 int num_dims, const size_t *volume, const size_t *dst_offsets, 192 const size_t *src_offsets, const size_t *dst_dimensions, 193 const size_t *src_dimensions, int dst_device, int src_device) { 194 DP("Call to omp_target_memcpy_rect, dst device %d, src device %d, " 195 "dst addr " DPxMOD ", src addr " DPxMOD ", dst offsets " DPxMOD ", " 196 "src offsets " DPxMOD ", dst dims " DPxMOD ", src dims " DPxMOD ", " 197 "volume " DPxMOD ", element size %zu, num_dims %d\n", dst_device, 198 src_device, DPxPTR(dst), DPxPTR(src), DPxPTR(dst_offsets), 199 DPxPTR(src_offsets), DPxPTR(dst_dimensions), DPxPTR(src_dimensions), 200 DPxPTR(volume), element_size, num_dims); 201 202 if (!(dst || src)) { 203 DP("Call to omp_target_memcpy_rect returns max supported dimensions %d\n", 204 INT_MAX); 205 return INT_MAX; 206 } 207 208 if (!dst || !src || element_size < 1 || num_dims < 1 || !volume || 209 !dst_offsets || !src_offsets || !dst_dimensions || !src_dimensions) { 210 DP("Call to omp_target_memcpy_rect with invalid arguments\n"); 211 return OFFLOAD_FAIL; 212 } 213 214 int rc; 215 if (num_dims == 1) { 216 rc = omp_target_memcpy(dst, src, element_size * volume[0], 217 element_size * dst_offsets[0], element_size * src_offsets[0], 218 dst_device, src_device); 219 } else { 220 size_t dst_slice_size = element_size; 221 size_t src_slice_size = element_size; 222 for (int i=1; i<num_dims; ++i) { 223 dst_slice_size *= dst_dimensions[i]; 224 src_slice_size *= src_dimensions[i]; 225 } 226 227 size_t dst_off = dst_offsets[0] * dst_slice_size; 228 size_t src_off = src_offsets[0] * src_slice_size; 229 for (size_t i=0; i<volume[0]; ++i) { 230 rc = omp_target_memcpy_rect((char *) dst + dst_off + dst_slice_size * i, 231 (char *) src + src_off + src_slice_size * i, element_size, 232 num_dims - 1, volume + 1, dst_offsets + 1, src_offsets + 1, 233 dst_dimensions + 1, src_dimensions + 1, dst_device, src_device); 234 235 if (rc) { 236 DP("Recursive call to omp_target_memcpy_rect returns unsuccessfully\n"); 237 return rc; 238 } 239 } 240 } 241 242 DP("omp_target_memcpy_rect returns %d\n", rc); 243 return rc; 244 } 245 246 EXTERN int omp_target_associate_ptr(void *host_ptr, void *device_ptr, 247 size_t size, size_t device_offset, int device_num) { 248 DP("Call to omp_target_associate_ptr with host_ptr " DPxMOD ", " 249 "device_ptr " DPxMOD ", size %zu, device_offset %zu, device_num %d\n", 250 DPxPTR(host_ptr), DPxPTR(device_ptr), size, device_offset, device_num); 251 252 if (!host_ptr || !device_ptr || size <= 0) { 253 DP("Call to omp_target_associate_ptr with invalid arguments\n"); 254 return OFFLOAD_FAIL; 255 } 256 257 if (device_num == omp_get_initial_device()) { 258 DP("omp_target_associate_ptr: no association possible on the host\n"); 259 return OFFLOAD_FAIL; 260 } 261 262 if (!device_is_ready(device_num)) { 263 DP("omp_target_associate_ptr returns OFFLOAD_FAIL\n"); 264 return OFFLOAD_FAIL; 265 } 266 267 DeviceTy& Device = Devices[device_num]; 268 void *device_addr = (void *)((uint64_t)device_ptr + (uint64_t)device_offset); 269 int rc = Device.associatePtr(host_ptr, device_addr, size); 270 DP("omp_target_associate_ptr returns %d\n", rc); 271 return rc; 272 } 273 274 EXTERN int omp_target_disassociate_ptr(void *host_ptr, int device_num) { 275 DP("Call to omp_target_disassociate_ptr with host_ptr " DPxMOD ", " 276 "device_num %d\n", DPxPTR(host_ptr), device_num); 277 278 if (!host_ptr) { 279 DP("Call to omp_target_associate_ptr with invalid host_ptr\n"); 280 return OFFLOAD_FAIL; 281 } 282 283 if (device_num == omp_get_initial_device()) { 284 DP("omp_target_disassociate_ptr: no association possible on the host\n"); 285 return OFFLOAD_FAIL; 286 } 287 288 if (!device_is_ready(device_num)) { 289 DP("omp_target_disassociate_ptr returns OFFLOAD_FAIL\n"); 290 return OFFLOAD_FAIL; 291 } 292 293 DeviceTy& Device = Devices[device_num]; 294 int rc = Device.disassociatePtr(host_ptr); 295 DP("omp_target_disassociate_ptr returns %d\n", rc); 296 return rc; 297 } 298