/*
 * StarPU
 * Copyright (C) Université Bordeaux 1, CNRS 2008-2010 (see AUTHORS file)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU Lesser General Public License in COPYING.LGPL for more details.
 */

#include <starpu.h>
#include <common/config.h>
#include <common/utils.h>
#include <core/sched_policy.h>
#include <datawizard/datastats.h>
#include <common/fxt.h>
#include "copy_driver.h"
#include "memalloc.h"
#include <starpu_opencl.h>
#include <starpu_cuda.h>
#include <profiling/profiling.h>

void _starpu_wake_all_blocked_workers_on_node(unsigned nodeid)
{
	/* wake up all workers on that memory node */
	unsigned cond_id;

	starpu_mem_node_descr * const descr = _starpu_get_memory_node_description();

	PTHREAD_RWLOCK_RDLOCK(&descr->conditions_rwlock);

	unsigned nconds = descr->condition_count[nodeid];
	for (cond_id = 0; cond_id < nconds; cond_id++)
	{
		struct _cond_and_mutex *condition;
		condition  = &descr->conditions_attached_to_node[nodeid][cond_id];

		/* wake anybody waiting on that condition */
		PTHREAD_MUTEX_LOCK(condition->mutex);
		PTHREAD_COND_BROADCAST(condition->cond);
		PTHREAD_MUTEX_UNLOCK(condition->mutex);
	}

	PTHREAD_RWLOCK_UNLOCK(&descr->conditions_rwlock);
}

void starpu_wake_all_blocked_workers(void)
{
	/* workers may be blocked on the various queues' conditions */
	unsigned cond_id;

	starpu_mem_node_descr * const descr = _starpu_get_memory_node_description();

	PTHREAD_RWLOCK_RDLOCK(&descr->conditions_rwlock);

	unsigned nconds = descr->total_condition_count;
	for (cond_id = 0; cond_id < nconds; cond_id++)
	{
		struct _cond_and_mutex *condition;
		condition  = &descr->conditions_all[cond_id];

		/* wake anybody waiting on that condition */
		PTHREAD_MUTEX_LOCK(condition->mutex);
		PTHREAD_COND_BROADCAST(condition->cond);
		PTHREAD_MUTEX_UNLOCK(condition->mutex);
	}

	PTHREAD_RWLOCK_UNLOCK(&descr->conditions_rwlock);
}

#ifdef STARPU_USE_FXT
/* we need to identify each communication so that we can match the beginning
 * and the end of a communication in the trace, so we use a unique identifier
 * per communication */
static unsigned communication_cnt = 0;
#endif

static int copy_data_1_to_1_generic(starpu_data_handle handle, uint32_t src_node, uint32_t dst_node, struct starpu_data_request_s *req __attribute__((unused)))
{
	int ret = 0;

	const struct starpu_data_copy_methods *copy_methods = handle->ops->copy_methods;

	starpu_node_kind src_kind = _starpu_get_node_kind(src_node);
	starpu_node_kind dst_kind = _starpu_get_node_kind(dst_node);

	STARPU_ASSERT(handle->per_node[src_node].refcnt);
	STARPU_ASSERT(handle->per_node[dst_node].refcnt);

	STARPU_ASSERT(handle->per_node[src_node].allocated);
	STARPU_ASSERT(handle->per_node[dst_node].allocated);

#ifdef STARPU_USE_CUDA
	cudaError_t cures;
	cudaStream_t *stream;
#endif

	void *src_interface = starpu_data_get_interface_on_node(handle, src_node);
	void *dst_interface = starpu_data_get_interface_on_node(handle, dst_node);

	switch (_STARPU_MEMORY_NODE_TUPLE(src_kind,dst_kind)) {
	case _STARPU_MEMORY_NODE_TUPLE(STARPU_CPU_RAM,STARPU_CPU_RAM):
		/* STARPU_CPU_RAM -> STARPU_CPU_RAM */
		STARPU_ASSERT(copy_methods->ram_to_ram);
		copy_methods->ram_to_ram(src_interface, src_node, dst_interface, dst_node);
		break;
#ifdef STARPU_USE_CUDA
	case _STARPU_MEMORY_NODE_TUPLE(STARPU_CUDA_RAM,STARPU_CPU_RAM):
		/* CUBLAS_RAM -> STARPU_CPU_RAM */
		/* only the proper CUBLAS thread can initiate this ! */
		if (_starpu_get_local_memory_node() == src_node) {
			/* only the proper CUBLAS thread can initiate this directly ! */
			STARPU_ASSERT(copy_methods->cuda_to_ram);
			if (!req || !copy_methods->cuda_to_ram_async) {
				/* this is not associated to a request so it's synchronous */
				copy_methods->cuda_to_ram(src_interface, src_node, dst_interface, dst_node);
			}
			else {
				cures = cudaEventCreate(&req->async_channel.cuda_event);
				if (STARPU_UNLIKELY(cures != cudaSuccess)) STARPU_CUDA_REPORT_ERROR(cures);

				stream = starpu_cuda_get_local_stream();
				ret = copy_methods->cuda_to_ram_async(src_interface, src_node, dst_interface, dst_node, stream);

				cures = cudaEventRecord(req->async_channel.cuda_event, *stream);
				if (STARPU_UNLIKELY(cures != cudaSuccess)) STARPU_CUDA_REPORT_ERROR(cures);
			}
		}
		else {
			/* we should not have a blocking call ! */
			STARPU_ABORT();
		}
		break;
	case _STARPU_MEMORY_NODE_TUPLE(STARPU_CPU_RAM,STARPU_CUDA_RAM):
		/* STARPU_CPU_RAM -> CUBLAS_RAM */
		/* only the proper CUBLAS thread can initiate this ! */
		STARPU_ASSERT(_starpu_get_local_memory_node() == dst_node);
		STARPU_ASSERT(copy_methods->ram_to_cuda);
		if (!req || !copy_methods->ram_to_cuda_async) {
			/* this is not associated to a request so it's synchronous */
			copy_methods->ram_to_cuda(src_interface, src_node, dst_interface, dst_node);
		}
		else {
			cures = cudaEventCreate(&req->async_channel.cuda_event);
			if (STARPU_UNLIKELY(cures != cudaSuccess)) STARPU_CUDA_REPORT_ERROR(cures);

			stream = starpu_cuda_get_local_stream();
			ret = copy_methods->ram_to_cuda_async(src_interface, src_node, dst_interface, dst_node, stream);

			cures = cudaEventRecord(req->async_channel.cuda_event, *stream);
			if (STARPU_UNLIKELY(cures != cudaSuccess)) STARPU_CUDA_REPORT_ERROR(cures);
		}
		break;
#endif
#ifdef STARPU_USE_OPENCL
	case _STARPU_MEMORY_NODE_TUPLE(STARPU_OPENCL_RAM,STARPU_CPU_RAM):
		/* OpenCL -> RAM */
		if (_starpu_get_local_memory_node() == src_node) {
			STARPU_ASSERT(copy_methods->opencl_to_ram);
			if (!req || !copy_methods->opencl_to_ram_async) {
				/* this is not associated to a request so it's synchronous */
				copy_methods->opencl_to_ram(src_interface, src_node, dst_interface, dst_node);
			}
			else {
				ret = copy_methods->opencl_to_ram_async(src_interface, src_node, dst_interface, dst_node, &(req->async_channel.opencl_event));
			}
		}
		else {
			/* we should not have a blocking call ! */
			STARPU_ABORT();
		}
		break;
	case _STARPU_MEMORY_NODE_TUPLE(STARPU_CPU_RAM,STARPU_OPENCL_RAM):
		/* STARPU_CPU_RAM -> STARPU_OPENCL_RAM */
		STARPU_ASSERT(_starpu_get_local_memory_node() == dst_node);
		STARPU_ASSERT(copy_methods->ram_to_opencl);
		if (!req || !copy_methods->ram_to_opencl_async) {
			/* this is not associated to a request so it's synchronous */
			copy_methods->ram_to_opencl(src_interface, src_node, dst_interface, dst_node);
		}
		else {
			ret = copy_methods->ram_to_opencl_async(src_interface, src_node, dst_interface, dst_node, &(req->async_channel.opencl_event));
		}
		break;
#endif
	default:
		STARPU_ABORT();
		break;
	}

	return ret;
}

int __attribute__((warn_unused_result)) _starpu_driver_copy_data_1_to_1(starpu_data_handle handle, uint32_t src_node, 
		uint32_t dst_node, unsigned donotread, struct starpu_data_request_s *req, unsigned may_alloc)
{
	if (!donotread)
	{
		STARPU_ASSERT(handle->per_node[src_node].allocated);
		STARPU_ASSERT(handle->per_node[src_node].refcnt);
	}

	int ret_alloc, ret_copy;
	unsigned __attribute__((unused)) com_id = 0;

	/* first make sure the destination has an allocated buffer */
	ret_alloc = _starpu_allocate_memory_on_node(handle, dst_node, may_alloc);
	if (ret_alloc)
		goto nomem;

	STARPU_ASSERT(handle->per_node[dst_node].allocated);
	STARPU_ASSERT(handle->per_node[dst_node].refcnt);

	/* if there is no need to actually read the data, 
	 * we do not perform any transfer */
	if (!donotread) {
		STARPU_ASSERT(handle->ops);
		//STARPU_ASSERT(handle->ops->copy_data_1_to_1);

		size_t size = _starpu_data_get_size(handle);
		_starpu_bus_update_profiling_info((int)src_node, (int)dst_node, size);
		
#ifdef STARPU_USE_FXT
		com_id = STARPU_ATOMIC_ADD(&communication_cnt, 1);

		if (req)
			req->com_id = com_id;
#endif

		/* for now we set the size to 0 in the FxT trace XXX */
		STARPU_TRACE_START_DRIVER_COPY(src_node, dst_node, 0, com_id);
		ret_copy = copy_data_1_to_1_generic(handle, src_node, dst_node, req);

#ifdef STARPU_USE_FXT
		if (ret_copy != EAGAIN)
		{
			size_t size = _starpu_data_get_size(handle);
			STARPU_TRACE_END_DRIVER_COPY(src_node, dst_node, size, com_id);
		}
#endif

		return ret_copy;
	}

	return 0;

nomem:
	return ENOMEM;
}

void _starpu_driver_wait_request_completion(starpu_async_channel *async_channel __attribute__ ((unused)),
					unsigned handling_node)
{
	starpu_node_kind kind = _starpu_get_node_kind(handling_node);
#ifdef STARPU_USE_CUDA
	cudaEvent_t event;
	cudaError_t cures;
#endif

	switch (kind) {
#ifdef STARPU_USE_CUDA
		case STARPU_CUDA_RAM:
			event = (*async_channel).cuda_event;

			cures = cudaEventSynchronize(event);
			if (STARPU_UNLIKELY(cures))
				STARPU_CUDA_REPORT_ERROR(cures);

			cures = cudaEventDestroy(event);
			if (STARPU_UNLIKELY(cures))
				STARPU_CUDA_REPORT_ERROR(cures);

			break;
#endif
#ifdef STARPU_USE_OPENCL
      case STARPU_OPENCL_RAM:
         {
            cl_event opencl_event = (*async_channel).opencl_event;
            if (opencl_event == NULL) STARPU_ABORT();
            cl_int err = clWaitForEvents(1, &opencl_event);
            if (err != CL_SUCCESS) STARPU_OPENCL_REPORT_ERROR(err);
            clReleaseEvent(opencl_event);
         }
         break;
#endif
		case STARPU_CPU_RAM:
		default:
			STARPU_ABORT();
	}
}

unsigned _starpu_driver_test_request_completion(starpu_async_channel *async_channel __attribute__ ((unused)),
					unsigned handling_node)
{
	starpu_node_kind kind = _starpu_get_node_kind(handling_node);
	unsigned success;
#ifdef STARPU_USE_CUDA
	cudaEvent_t event;
#endif

	switch (kind) {
#ifdef STARPU_USE_CUDA
		case STARPU_CUDA_RAM:
			event = (*async_channel).cuda_event;

			success = (cudaEventQuery(event) == cudaSuccess);
			if (success)
				cudaEventDestroy(event);

			break;
#endif
#ifdef STARPU_USE_OPENCL
      case STARPU_OPENCL_RAM:
         {
            cl_int event_status;
            cl_event opencl_event = (*async_channel).opencl_event;
            if (opencl_event == NULL) STARPU_ABORT();
            cl_int err = clGetEventInfo(opencl_event, CL_EVENT_COMMAND_EXECUTION_STATUS, sizeof(event_status), &event_status, NULL);
            if (err != CL_SUCCESS) STARPU_OPENCL_REPORT_ERROR(err);
            success = (event_status == CL_COMPLETE);
            break;
         }
#endif
		case STARPU_CPU_RAM:
		default:
			STARPU_ABORT();
			success = 0;
	}

	return success;
}