Messages in this thread | | | Date | Tue, 10 May 2022 17:46:50 +0530 | Subject | Re: [PATCH] dmabuf: ensure unique directory name for dmabuf stats | From | Charan Teja Kalla <> |
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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.
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