Re: [PATCH] dmabuf: ensure unique directory name for dmabuf stats

[Charan Teja Kalla <quic_charante@quicinc.com>]

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.