Thanks Christian for the inputs!! On 5/10/2022 5:05 PM, Christian König wrote: > >> And what's to keep the seconds field from also being the same? > > Well exporting two DMA-bufs with the same ino in the same nanosecond > should be basically impossible, but I would rather opt for using a 64bit > atomic in that function. > > This should be 100% UAPI compatible and even if we manage to create one > buffer ever ns we need ~500years to wrap around. I see that the inode->i_ctime->tv_sec is already defined as 64bit(time64_t tv_sec), hence used it. This way we don't need extra static atomic_t variable just to get a unique name. Just pasting excerpt from the reply posted to Greg about why this secs will always be a unique: with secs field added, to get the same inode-secs string, the uint should overflow in the same second which is impossible. Let me know If you still opt for atomic variable only.
