Am 17.06.24 um 16:55 schrieb Michel Dänzer:
On 2024-06-17 16:52, Christian König wrote:
Am 17.06.24 um 16:50 schrieb Michel Dänzer:
On 2024-06-17 12:29, Pierre Ossman wrote:
Just to avoid any uncertainty, are both of these things done implicitly by
gbm_bo_map()/gbm_bo_unmap()?
I did test adding those steps just in case, but unfortunately did not see an
improvement. My order was:
1. gbm_bo_import(GBM_BO_USE_RENDERING)
2. gbm_bo_get_fd()
3. Wait for client to request displaying the buffer
4. gbm_bo_map(GBM_BO_TRANSFER_READ)
5. select(fd+1, &fds, NULL, NULL, NULL)
*If* select() is needed, it needs to be before gbm_bo_map(), because the latter
may perform a blit from the real BO to a staging one for CPU access.
But don't you then need to wait for the blit to finish?
No, gbm_bo_map() must handle that internally. When it returns, the CPU must see
the correct contents.
Ah, ok in that case that function does more than I expected.
Thanks,
Christian.
6. ioctl(DMA_BUF_IOCTL_SYNC, &{ .flags = DMA_BUF_SYNC_START | DMA_BUF_SYNC_READ
})
gbm_bo_map() should do this internally if needed.
7. pixman_blt()
8. gbm_bo_unmap()
