How to release ashmem

Question

Allocating and using ashmem works well:

ashmemFD = open("/dev/ashmem", O_RDWR);
int ret = ioctl(ashmemFD, ASHMEM_SET_NAME, "vf");
ioctl(ashmemFD, ASHMEM_SET_SIZE, size);
ashmap = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, ashmemFD, 0);

But the question is, is it enough to just unmap it after use, or do I need to do more to release the memory again?

munmap((void*) ashmap,size);

score 1 · Accepted Answer · answered Jun 24 '14 at 08:53

You need to close all file descriptors to the ashmem region after unmapping it.

Ashmem regions can be seen as memory-based files handled by the kernel. As long as there is an open file descriptor to one of them, it will be kept in memory.

Hope this helps.

How to release ashmem

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