#include <vector>
#ifdef GGML_WEBGPU_DEBUG
-# define WEBGPU_LOG_DEBUG(msg) std::cout << msg << std::endl
+# define WEBGPU_LOG_DEBUG(msg) std::cout << msg << std::endl
+# define WEBGPU_DEBUG_BUF_ELEMS 32
#else
# define WEBGPU_LOG_DEBUG(msg) ((void) 0)
#endif // GGML_WEBGPU_DEBUG
/* Constants */
-#define WEBGPU_COMMAND_SUBMIT_BATCH_SIZE 16
-#define WEBGPU_MUL_MAT_WG_SIZE 64
-#define WEBGPU_NUM_PARAM_BUFS 100
-#define WEBGPU_PARAMS_BUF_SIZE_BYTES 256
-#define WEBGPU_STORAGE_BUF_BINDING_MULT 4 // a storage buffer binding size must be a multiple of 4
+#define WEBGPU_COMMAND_SUBMIT_BATCH_SIZE 16
+#define WEBGPU_MUL_MAT_WG_SIZE 64
+#define WEBGPU_NUM_PARAM_BUFS 100
+#define WEBGPU_PARAMS_BUF_SIZE_BYTES 128 // enough for 32 parameters
+#define WEBGPU_NUM_SET_ROWS_ERROR_BUFS 32
+#define WEBGPU_SET_ROWS_ERROR_BUF_SIZE_BYTES 4
+#define WEBGPU_STORAGE_BUF_BINDING_MULT 4 // a storage buffer binding size must be a multiple of 4
/* End Constants */
wgpu::BufferUsage usage,
const char * label);
-struct webgpu_param_bufs {
+struct webgpu_pool_bufs {
wgpu::Buffer host_buf;
wgpu::Buffer dev_buf;
};
// Holds a pool of parameter buffers for WebGPU operations
-struct webgpu_param_buf_pool {
- std::vector<webgpu_param_bufs> free;
+struct webgpu_buf_pool {
+ std::vector<webgpu_pool_bufs> free;
std::mutex mutex;
std::condition_variable cv;
- void init(wgpu::Device device) {
- for (int i = 0; i < WEBGPU_NUM_PARAM_BUFS; i++) {
+ void init(wgpu::Device device,
+ int num_bufs,
+ size_t buf_size,
+ wgpu::BufferUsage dev_buf_usage,
+ wgpu::BufferUsage host_buf_usage) {
+ for (int i = 0; i < num_bufs; i++) {
wgpu::Buffer host_buf;
wgpu::Buffer dev_buf;
- ggml_webgpu_create_buffer(device,
- host_buf,
- WEBGPU_PARAMS_BUF_SIZE_BYTES,
- wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::MapWrite,
- "ggml_webgpu_host_params_buf");
- ggml_webgpu_create_buffer(device,
- dev_buf,
- WEBGPU_PARAMS_BUF_SIZE_BYTES,
- wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Uniform,
- "ggml_webgpu_dev_params_buf");
+ ggml_webgpu_create_buffer(device, host_buf, buf_size, host_buf_usage, "ggml_webgpu_host_pool_buf");
+ ggml_webgpu_create_buffer(device, dev_buf, buf_size, dev_buf_usage, "ggml_webgpu_dev_pool_buf");
free.push_back({ host_buf, dev_buf });
}
}
- webgpu_param_bufs alloc_bufs() {
+ webgpu_pool_bufs alloc_bufs() {
std::unique_lock<std::mutex> lock(mutex);
cv.wait(lock, [this] { return !free.empty(); });
- webgpu_param_bufs bufs = free.back();
+ webgpu_pool_bufs bufs = free.back();
free.pop_back();
return bufs;
}
- void free_bufs(std::vector<webgpu_param_bufs> bufs) {
+ void free_bufs(std::vector<webgpu_pool_bufs> bufs) {
std::lock_guard<std::mutex> lock(mutex);
free.insert(free.end(), bufs.begin(), bufs.end());
cv.notify_all();
bool device_init = false;
- webgpu_param_buf_pool param_buf_pool;
+ webgpu_buf_pool param_buf_pool;
+ webgpu_buf_pool set_rows_error_buf_pool;
wgpu::ComputePipeline memset_pipeline;
wgpu::ComputePipeline mul_mat_pipeline;
+ wgpu::ComputePipeline set_rows_pipeline;
wgpu::ComputePipeline cpy_pipeline;
size_t memset_bytes_per_thread;
std::vector<wgpu::CommandBuffer> staged_command_bufs;
// Parameter buffers associated with the staged command buffers
- std::vector<webgpu_param_bufs> staged_param_bufs;
+ std::vector<webgpu_pool_bufs> staged_param_bufs;
+ // Buffers associated with set_rows operations, used to store potential errors
+ std::vector<webgpu_pool_bufs> staged_set_row_error_bufs;
std::vector<wgpu::FutureWaitInfo> callback_futures;
+
+#ifdef GGML_WEBGPU_DEBUG
+ wgpu::Buffer debug_host_buf;
+ wgpu::Buffer debug_dev_buf;
+#endif
};
typedef std::shared_ptr<webgpu_context_struct> webgpu_context;
return;
}
ctx->queue.Submit(ctx->staged_command_bufs.size(), ctx->staged_command_bufs.data());
+
+ // If there are SET_ROWS operations in this submission, copy their error buffers to the host.
+ if (ctx->staged_set_row_error_bufs.size() > 0) {
+ wgpu::CommandEncoder encoder = ctx->device.CreateCommandEncoder();
+ for (auto & error_bufs : ctx->staged_set_row_error_bufs) {
+ // Copy the error buffer to the host buffer
+ encoder.CopyBufferToBuffer(error_bufs.dev_buf, 0, error_bufs.host_buf, 0, error_bufs.host_buf.GetSize());
+ }
+ wgpu::CommandBuffer commands = encoder.Finish();
+ ctx->queue.Submit(1, &commands);
+ }
+
ctx->staged_command_bufs.clear();
- std::vector<webgpu_param_bufs> staged_param_bufs = std::move(ctx->staged_param_bufs);
+ std::vector<webgpu_pool_bufs> staged_param_bufs = std::move(ctx->staged_param_bufs);
+ std::vector<webgpu_pool_bufs> staged_set_row_error_bufs = std::move(ctx->staged_set_row_error_bufs);
// Free the staged parameter buffers once the submission completes
- wgpu::Future f = ctx->queue.OnSubmittedWorkDone(
+ wgpu::Future p_f = ctx->queue.OnSubmittedWorkDone(
wgpu::CallbackMode::AllowSpontaneous,
[ctx, staged_param_bufs](wgpu::QueueWorkDoneStatus status, wgpu::StringView message) {
if (status != wgpu::QueueWorkDoneStatus::Success) {
GGML_LOG_ERROR("ggml_webgpu: Failed to submit commands: %s\n", message.data);
}
- // Free the staged parameter buffers
+ // Free the staged buffers
ctx->param_buf_pool.free_bufs(staged_param_bufs);
});
- ctx->callback_futures.push_back({ f });
+ ctx->callback_futures.push_back({ p_f });
+
+ // Check for errrors in SET_ROWS operations
+ for (auto & error_bufs : staged_set_row_error_bufs) {
+ wgpu::Future f = error_bufs.host_buf.MapAsync(
+ wgpu::MapMode::Read,
+ 0,
+ error_bufs.host_buf.GetSize(),
+ wgpu::CallbackMode::AllowSpontaneous,
+ [ctx, error_bufs](wgpu::MapAsyncStatus status, wgpu::StringView message) {
+ if (status != wgpu::MapAsyncStatus::Success) {
+ GGML_LOG_ERROR("ggml_webgpu: Failed to map error buffer: %s\n", message.data);
+ } else {
+ const uint32_t * error_data = (const uint32_t *) error_bufs.host_buf.GetConstMappedRange();
+ if (*error_data) {
+ GGML_ABORT("ggml_webgpu: SET_ROWS index > 2^32, unsupported.");
+ }
+ // We can't unmap in here due to WebGPU reentrancy limitations.
+ ctx->set_rows_error_buf_pool.free_bufs({ error_bufs });
+ }
+ });
+ ctx->callback_futures.push_back({ f });
+ }
}
static void ggml_backend_webgpu_map_buffer(webgpu_context & ctx,
UINT64_MAX);
}
+#ifdef GGML_WEBGPU_DEBUG
+// This function adds debugging information to shaders, as WebGPU does not support printing directly.
+// To use, add a bind group entry to the setup for the shader you are debugging, add the buffer and
+// debug statements in the shader, and then call this function after encoding the commands and submitting them.
+static void ggml_backend_webgpu_debug(webgpu_context & ctx) {
+ wgpu::CommandEncoder encoder = ctx->device.CreateCommandEncoder();
+ encoder.CopyBufferToBuffer(ctx->debug_dev_buf, 0, ctx->debug_host_buf, 0, ctx->debug_host_buf.GetSize());
+ wgpu::CommandBuffer commands = encoder.Finish();
+ ctx->queue.Submit(1, &commands);
+
+ ggml_backend_webgpu_map_buffer(ctx, ctx->debug_host_buf, wgpu::MapMode::Read, 0, ctx->debug_host_buf.GetSize());
+ const uint32_t * debug_data = (const uint32_t *) ctx->debug_host_buf.GetConstMappedRange();
+ std::cout << "debug data:";
+ for (size_t i = 0; i < WEBGPU_DEBUG_BUF_ELEMS; i++) {
+ std::cout << " " << i << ": " << debug_data[i];
+ }
+ std::cout << "\n";
+ ctx->debug_host_buf.Unmap();
+}
+#endif
+
static void ggml_backend_webgpu_build_and_enqueue(webgpu_context & ctx,
wgpu::ComputePipeline & pipeline,
std::vector<uint32_t> params,
std::vector<wgpu::BindGroupEntry> bind_group_entries,
uint32_t wg_x,
bool submit_and_wait = false) {
- webgpu_param_bufs params_bufs = ctx->param_buf_pool.alloc_bufs();
+ webgpu_pool_bufs params_bufs = ctx->param_buf_pool.alloc_bufs();
ggml_backend_webgpu_map_buffer(ctx, params_bufs.host_buf, wgpu::MapMode::Write, 0, params_bufs.host_buf.GetSize());
uint32_t * _params = (uint32_t *) params_bufs.host_buf.GetMappedRange();
ggml_backend_webgpu_build_and_enqueue(ctx, ctx->cpy_pipeline, params, entries, wg_x);
}
+static void ggml_webgpu_set_rows(webgpu_context & ctx, ggml_tensor * src, ggml_tensor * idx, ggml_tensor * dst) {
+ // For set rows specifically, we need to check if src and idx are empty tensors.
+ if (ggml_is_empty(src) || ggml_is_empty(idx)) {
+ return;
+ }
+
+ webgpu_pool_bufs error_bufs = ctx->set_rows_error_buf_pool.alloc_bufs();
+ if (error_bufs.host_buf.GetMapState() == wgpu::BufferMapState::Mapped) {
+ error_bufs.host_buf.Unmap();
+ }
+
+ size_t src_offset = ggml_backend_webgpu_tensor_offset(src);
+ // assumes power of 2 offset alignment
+ size_t src_misalignment = src_offset & (ctx->limits.minStorageBufferOffsetAlignment - 1);
+ // align to minimum offset alignment
+ src_offset &= ~(ctx->limits.minStorageBufferOffsetAlignment - 1);
+ size_t idx_offset = ggml_backend_webgpu_tensor_offset(idx);
+ size_t idx_misalignment = idx_offset & (ctx->limits.minStorageBufferOffsetAlignment - 1);
+ idx_offset &= ~(ctx->limits.minStorageBufferOffsetAlignment - 1);
+ size_t dst_offset = ggml_backend_webgpu_tensor_offset(dst);
+ size_t dst_misalignment = dst_offset & (ctx->limits.minStorageBufferOffsetAlignment - 1);
+ dst_offset &= ~(ctx->limits.minStorageBufferOffsetAlignment - 1);
+
+ std::vector<uint32_t> params = { (uint32_t) (src_misalignment / ggml_type_size(src->type)),
+ (uint32_t) (idx_misalignment / ggml_type_size(idx->type)),
+ (uint32_t) (dst_misalignment / ggml_type_size(dst->type)),
+ // Convert byte-strides to element-strides
+ (uint32_t) (src->nb[1] / ggml_type_size(src->type)),
+ (uint32_t) (src->nb[2] / ggml_type_size(src->type)),
+ (uint32_t) (src->nb[3] / ggml_type_size(src->type)),
+ (uint32_t) (idx->nb[0] / ggml_type_size(idx->type)),
+ (uint32_t) (idx->nb[1] / ggml_type_size(idx->type)),
+ (uint32_t) (idx->nb[2] / ggml_type_size(idx->type)),
+ (uint32_t) (dst->nb[1] / ggml_type_size(dst->type)),
+ (uint32_t) (dst->nb[2] / ggml_type_size(dst->type)),
+ (uint32_t) (dst->nb[3] / ggml_type_size(dst->type)),
+ // Shape of src
+ (uint32_t) src->ne[0],
+ (uint32_t) src->ne[1],
+ (uint32_t) src->ne[2],
+ (uint32_t) src->ne[3],
+ // Shape of idx
+ (uint32_t) (idx->ne[1]),
+ (uint32_t) (idx->ne[2]) };
+
+ std::vector<wgpu::BindGroupEntry> entries = {
+ { .binding = 0,
+ .buffer = ggml_backend_webgpu_tensor_buf(src),
+ .offset = ggml_backend_webgpu_tensor_offset(src),
+ .size = ggml_nbytes(src) },
+ { .binding = 1,
+ .buffer = ggml_backend_webgpu_tensor_buf(idx),
+ .offset = ggml_backend_webgpu_tensor_offset(idx),
+ .size = ggml_nbytes(idx) },
+ { .binding = 2,
+ .buffer = ggml_backend_webgpu_tensor_buf(dst),
+ .offset = ggml_backend_webgpu_tensor_offset(dst),
+ .size = ggml_nbytes(dst) },
+ { .binding = 3, .buffer = error_bufs.dev_buf, .offset = 0, .size = error_bufs.dev_buf.GetSize() }
+ };
+
+ size_t max_wg_size = ctx->limits.maxComputeWorkgroupSizeX;
+ uint32_t wg_x = (src->ne[1] * src->ne[2] * src->ne[3] + max_wg_size - 1) / max_wg_size;
+
+ std::lock_guard<std::recursive_mutex> lock(ctx->mutex);
+ ctx->staged_set_row_error_bufs.push_back(error_bufs);
+
+ ggml_backend_webgpu_build_and_enqueue(ctx, ctx->set_rows_pipeline, params, entries, wg_x);
+}
+
static void ggml_webgpu_mul_mat(webgpu_context & ctx, ggml_tensor * src0, ggml_tensor * src1, ggml_tensor * dst) {
std::vector<uint32_t> params = {
(uint32_t) dst->ne[1], // number of rows in result (M)
ggml_webgpu_cpy(ctx, src0, node);
break;
}
+ case GGML_OP_SET_ROWS:
+ {
+ ggml_webgpu_set_rows(ctx, src0, src1, node);
+ break;
+ }
case GGML_OP_MUL_MAT:
{
ggml_webgpu_mul_mat(ctx, src0, src1, node);
ggml_webgpu_create_pipeline(webgpu_ctx->device, webgpu_ctx->mul_mat_pipeline, wgsl_mul_mat, "mul_mat");
}
+static void ggml_webgpu_init_set_rows_pipeline(webgpu_context & webgpu_ctx) {
+ std::vector<wgpu::ConstantEntry> constants(1);
+ constants[0].key = "wg_size";
+ constants[0].value = webgpu_ctx->limits.maxComputeWorkgroupSizeX;
+ ggml_webgpu_create_pipeline(
+ webgpu_ctx->device, webgpu_ctx->set_rows_pipeline, wgsl_set_rows, "set_rows", constants);
+}
+
static void ggml_webgpu_init_cpy_pipeline(webgpu_context & webgpu_ctx) {
std::vector<wgpu::ConstantEntry> constants(1);
constants[0].key = "wg_size";
webgpu_ctx->queue = webgpu_ctx->device.GetQueue();
// Create buffer pool for shader parameters
- webgpu_ctx->param_buf_pool.init(webgpu_ctx->device);
+ webgpu_ctx->param_buf_pool.init(webgpu_ctx->device,
+ WEBGPU_NUM_PARAM_BUFS,
+ WEBGPU_PARAMS_BUF_SIZE_BYTES,
+ wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Uniform,
+ wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::MapWrite);
+ webgpu_ctx->set_rows_error_buf_pool.init(webgpu_ctx->device,
+ WEBGPU_NUM_SET_ROWS_ERROR_BUFS,
+ WEBGPU_SET_ROWS_ERROR_BUF_SIZE_BYTES,
+ wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::Storage,
+ wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::MapRead);
ggml_webgpu_init_memset_pipeline(webgpu_ctx);
ggml_webgpu_init_mul_mat_pipeline(webgpu_ctx);
+ ggml_webgpu_init_set_rows_pipeline(webgpu_ctx);
ggml_webgpu_init_cpy_pipeline(webgpu_ctx);
+
+#ifdef GGML_WEBGPU_DEBUG
+ // Initialize debug buffers
+ ggml_webgpu_create_buffer(webgpu_ctx->device,
+ webgpu_ctx->debug_host_buf,
+ WEBGPU_DEBUG_BUF_ELEMS * sizeof(uint32_t),
+ wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::MapRead,
+ "debug_host_buf");
+ ggml_webgpu_create_buffer(webgpu_ctx->device,
+ webgpu_ctx->debug_dev_buf,
+ WEBGPU_DEBUG_BUF_ELEMS * sizeof(uint32_t),
+ wgpu::BufferUsage::Storage | wgpu::BufferUsage::CopySrc,
+ "debug_dev_buf");
+#endif
webgpu_ctx->device_init = true;
}
case GGML_OP_VIEW:
case GGML_OP_PERMUTE:
return true;
- case GGML_OP_CPY:
+ case GGML_OP_CPY | GGML_OP_SET_ROWS:
return op->type == GGML_TYPE_F16 && op->src[0]->type == GGML_TYPE_F32;
case GGML_OP_MUL_MAT:
return op->src[0]->type == GGML_TYPE_F32 && op->src[1]->type == GGML_TYPE_F32;