Function: reserve_mem_address

C Prototype	aclError aclrtReserveMemAddress(void virPtr, size_t size, size_t alignment, void expectPtr, uint64_t flags)*
Python Function	vir_ptr, ret = acl.rt.reserve_mem_address(size, alignment, expect_ptr, flags)
Function Usage	Reserves virtual memory. This API needs to work with other APIs to allocate virtual memory with consecutive addresses and maximize the use of physical memory. Call acl.rt.reserve_mem_address to allocate virtual memory. Call acl.rt.malloc_physical to allocate physical memory. Call acl.rt.map_mem to map the virtual memory to the physical memory. Call specific task APIs to execute tasks. Call acl.rt.unmap_mem to unmap the virtual memory from the physical memory. Call acl.rt.free_physical to free the physical memory. Call acl.rt.release_mem_address to free the virtual memory.
Input Description	size: int, size of the virtual address space (in byte) Must not be 0. alignment: int, alignment value of the virtual address. This parameter is reserved and can only be set to 0. expect_ptr: specifies the start address of the virtual address space to be returned. This parameter is reserved and can only be set to 0. flags: huge page or common page flag. The flag must be the same as the memory type of acl.rt.malloc_physical. Value options: 0: normal page 0: normal page
Return Value	vir_ptr: int, pointing to the address of the allocated virtual address space. ret: int, error code. 0 indicates success. Other values indicate failure.
Restrictions	This API is not supported in Ascend RC form.

Parent topic: Memory Management