diff options
| -rw-r--r-- | include/cuda/cuda.h | 3 | ||||
| -rw-r--r-- | libgomp/libgomp.texi | 7 | ||||
| -rw-r--r-- | libgomp/plugin/plugin-nvptx.c | 15 | ||||
| -rw-r--r-- | libgomp/target.c | 24 |
4 files changed, 45 insertions, 4 deletions
diff --git a/include/cuda/cuda.h b/include/cuda/cuda.h index 0dca4b3..804d08c 100644 --- a/include/cuda/cuda.h +++ b/include/cuda/cuda.h @@ -83,7 +83,8 @@ typedef enum { CU_DEVICE_ATTRIBUTE_MAX_THREADS_PER_MULTIPROCESSOR = 39, CU_DEVICE_ATTRIBUTE_ASYNC_ENGINE_COUNT = 40, CU_DEVICE_ATTRIBUTE_UNIFIED_ADDRESSING = 41, - CU_DEVICE_ATTRIBUTE_MAX_REGISTERS_PER_MULTIPROCESSOR = 82 + CU_DEVICE_ATTRIBUTE_MAX_REGISTERS_PER_MULTIPROCESSOR = 82, + CU_DEVICE_ATTRIBUTE_PAGEABLE_MEMORY_ACCESS = 88 } CUdevice_attribute; enum { diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi index 71d6210..2286863 100644 --- a/libgomp/libgomp.texi +++ b/libgomp/libgomp.texi @@ -6435,8 +6435,11 @@ The implementation remark: the next reverse offload region is only executed after the previous one returned. @item OpenMP code that has a @code{requires} directive with - @code{unified_shared_memory} will remove any nvptx device from the - list of available devices (``host fallback''). + @code{unified_shared_memory} runs on nvptx devices if and only if + all of those support the @code{pageableMemoryAccess} property;@footnote{ + @uref{https://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#um-requirements}} + otherwise, all nvptx device are removed from the list of available + devices (``host fallback''). @item The default per-warp stack size is 128 kiB; see also @code{-msoft-stack} in the GCC manual. @item The OpenMP routines @code{omp_target_memcpy_rect} and diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c index 5aad344..4cedc53 100644 --- a/libgomp/plugin/plugin-nvptx.c +++ b/libgomp/plugin/plugin-nvptx.c @@ -1201,8 +1201,23 @@ GOMP_OFFLOAD_get_num_devices (unsigned int omp_requires_mask) if (num_devices > 0 && ((omp_requires_mask & ~(GOMP_REQUIRES_UNIFIED_ADDRESS + | GOMP_REQUIRES_UNIFIED_SHARED_MEMORY | GOMP_REQUIRES_REVERSE_OFFLOAD)) != 0)) return -1; + /* Check whether host page access (direct or via migration) is supported; + if so, enable USM. Currently, capabilities is per device type, hence, + check all devices. */ + if (num_devices > 0 + && (omp_requires_mask & GOMP_REQUIRES_UNIFIED_SHARED_MEMORY)) + for (int dev = 0; dev < num_devices; dev++) + { + int pi; + CUresult r; + r = CUDA_CALL_NOCHECK (cuDeviceGetAttribute, &pi, + CU_DEVICE_ATTRIBUTE_PAGEABLE_MEMORY_ACCESS, dev); + if (r != CUDA_SUCCESS || pi == 0) + return -1; + } return num_devices; } diff --git a/libgomp/target.c b/libgomp/target.c index 5ec19ae..4868992 100644 --- a/libgomp/target.c +++ b/libgomp/target.c @@ -2969,8 +2969,25 @@ gomp_copy_back_icvs (struct gomp_device_descr *devicep, int device) if (item == NULL) return; + gomp_mutex_lock (&devicep->lock); + + struct splay_tree_s *mem_map = &devicep->mem_map; + struct splay_tree_key_s cur_node; + void *dev_ptr = NULL; + void *host_ptr = &item->icvs; - void *dev_ptr = omp_get_mapped_ptr (host_ptr, device); + cur_node.host_start = (uintptr_t) host_ptr; + cur_node.host_end = cur_node.host_start; + splay_tree_key n = gomp_map_0len_lookup (mem_map, &cur_node); + + if (n) + { + uintptr_t offset = cur_node.host_start - n->host_start; + dev_ptr = (void *) (n->tgt->tgt_start + n->tgt_offset + offset); + } + + gomp_mutex_unlock (&devicep->lock); + if (dev_ptr != NULL) gomp_copy_dev2host (devicep, NULL, host_ptr, dev_ptr, sizeof (struct gomp_offload_icvs)); @@ -5303,6 +5320,11 @@ gomp_target_init (void) { /* Augment DEVICES and NUM_DEVICES. */ + /* If USM has been requested and is supported by all devices + of this type, set the capability accordingly. */ + if (omp_requires_mask & GOMP_REQUIRES_UNIFIED_SHARED_MEMORY) + current_device.capabilities |= GOMP_OFFLOAD_CAP_SHARED_MEM; + devs = realloc (devs, (num_devs + new_num_devs) * sizeof (struct gomp_device_descr)); if (!devs) |