CODEWITHSUNDEEP
cuda
Rayne
Rayne

Reputation: 14977

Rewriting memory allocated via cudaHostAlloc()

I have a 100MB character array (h_array) that is allocated using cudaHostAlloc() with the flag cudaHostAllocWriteCombined.

The program first copies data into h_array on the host. When h_array is full, it will copy h_array to d_array on the device and some processing is done. When the processing is completed, h_array is reused in the sense that new data is copied to it again, starting from h_array[0]. The new data is meant to overwrite what was previously stored in h_array.

However, I'm getting segmentation fault when the new data is copied to h_array after processing is complete. There are no seg fault errors when I'm using regular malloc.

What is wrong? Can I not rewrite the memory when it's pinned?

Thank you!

Upvotes: 1

Views: 982

Answers (1)

ArchaeaSoftware
ArchaeaSoftware

Reputation: 4422

Your CUDA context is probably getting yanked out from under you somehow.

For example, if you allocate the pinned host memory in a thread that then exits, the memory will go away.

Make sure the thread that performs the allocation sticks around!

Upvotes: 1

Related Questions