/* * This file is part of the StarPU Handbook. * Copyright (C) 2009--2011 Universit@'e de Bordeaux * Copyright (C) 2010, 2011, 2012, 2013 Centre National de la Recherche Scientifique * Copyright (C) 2011, 2012 Institut National de Recherche en Informatique et Automatique * See the file version.doxy for copying conditions. */ /*! \defgroup API_Standard_Memory_Library Standard Memory Library \def starpu_data_malloc_pinned_if_possible \ingroup API_Standard_Memory_Library \deprecated Equivalent to starpu_malloc(). This macro is provided to avoid breaking old codes. \def starpu_data_free_pinned_if_possible \ingroup API_Standard_Memory_Library \deprecated Equivalent to starpu_free(). This macro is provided to avoid breaking old codes. \def STARPU_MALLOC_PINNED \ingroup API_Standard_Memory_Library Value passed to the function starpu_malloc_flags() to indicate the memory allocation should be pinned. \def STARPU_MALLOC_COUNT \ingroup API_Standard_Memory_Library Value passed to the function starpu_malloc_flags() to indicate the memory allocation should be in the limit defined by the environment variables \ref STARPU_LIMIT_CUDA_devid_MEM, \ref STARPU_LIMIT_CUDA_MEM, \ref STARPU_LIMIT_OPENCL_devid_MEM, \ref STARPU_LIMIT_OPENCL_MEM and \ref STARPU_LIMIT_CPU_MEM (see Section \ref HowToLimitMemoryPerNode). If no memory is available, it tries to reclaim memory from StarPU. Memory allocated this way needs to be freed by calling the function starpu_free_flags() with the same flag. \def STARPU_MALLOC_NORECLAIM \ingroup API_Standard_Memory_Library Value passed to the function starpu_malloc_flags() along STARPU_MALLOC_COUNT to indicate that while the memory allocation should be kept in the limits defined for STARPU_MALLOC_COUNT, no reclaiming should be performed by starpu_malloc_flags itself, thus potentially overflowing the memory node a bit. StarPU will reclaim memory after next task termination, according to the STARPU_MINIMUM_AVAILABLE_MEM and STARPU_TARGET_AVAILABLE_MEM environment variables. \fn int starpu_malloc_flags(void **A, size_t dim, int flags) \ingroup API_Standard_Memory_Library Performs a memory allocation based on the constraints defined by the given flag. \fn void starpu_malloc_set_align(size_t align) \ingroup API_Standard_Memory_Library This function sets an alignment constraints for starpu_malloc() allocations. align must be a power of two. This is for instance called automatically by the OpenCL driver to specify its own alignment constraints. \fn int starpu_malloc(void **A, size_t dim) \ingroup API_Standard_Memory_Library This function allocates data of the given size in main memory. It will also try to pin it in CUDA or OpenCL, so that data transfers from this buffer can be asynchronous, and thus permit data transfer and computation overlapping. The allocated buffer must be freed thanks to the starpu_free() function. \fn int starpu_free(void *A) \ingroup API_Standard_Memory_Library This function frees memory which has previously been allocated with starpu_malloc(). \fn int starpu_free_flags(void *A, size_t dim, int flags) \ingroup API_Standard_Memory_Library This function frees memory by specifying its size. The given flags should be consistent with the ones given to starpu_malloc_flags() when allocating the memory. \fn ssize_t starpu_memory_get_total(unsigned node) \ingroup API_Standard_Memory_Library If a memory limit is defined on the given node (see Section \ref HowToLimitMemoryPerNode), return the amount of total memory on the node. Otherwise return -1. \fn ssize_t starpu_memory_get_available(unsigned node) \ingroup API_Standard_Memory_Library If a memory limit is defined on the given node (see Section \ref HowToLimitMemoryPerNode), return the amount of available memory on the node. Otherwise return -1. \fn int starpu_memory_allocate(unsigned node, size_t size, int flags) \ingroup API_Standard_Memory_Library If a memory limit is defined on the given node (see Section \ref HowToLimitMemoryPerNode), try to allocate some of it. This does not actually allocate memory, but only accounts for it. This can be useful when the application allocates data another way, but want StarPU to be aware of the allocation size e.g. for memory reclaiming. By default, the function returns -ENOMEM if there is not enough room on the given node. \p flags can be either STARPU_MEMORY_WAIT or STARPU_MEMORY_OVERFLOW to change this. \fn void starpu_memory_deallocate(unsigned node, size_t size) \ingroup API_Standard_Memory_Library If a memory limit is defined on the given node (see Section \ref HowToLimitMemoryPerNode), free some of it. This does not actually free memory, but only accounts for it, like starpu_memory_allocate(). The amount does not have to be exactly the same as what was passed to starpu_memory_allocate(), only the eventual amount needs to be the same, i.e. one call to starpu_memory_allocate() can be followed by several calls to starpu_memory_deallocate() to declare the deallocation piece by piece. \fn void starpu_memory_wait_available(unsigned node, size_t size) \ingroup API_Standard_Memory_Library If a memory limit is defined on the given node (see Section \ref HowToLimitMemoryPerNode), this will wait for \p size bytes to become available on \p node. Of course, since another thread may be allocating memory concurrently, this does not necessarily mean that this amount will be actually available, just that it was reached. To atomically wait for some amount of memory and reserve it, starpu_memory_allocate() should be used with the STARPU_MEMORY_WAIT flag. \def STARPU_MEMORY_WAIT \ingroup API_Standard_Memory_Library Value passed to starpu_memory_allocate() to specify that the function should wait for the requested amount of memory to become available, and atomically allocate it. \def STARPU_MEMORY_OVERFLOW \ingroup API_Standard_Memory_Library Value passed to starpu_memory_allocate() to specify that the function should allocate the amount of memory, even if that means overflowing the total size of the memory node. */