On Wed, Jun 23, 2021 at 1:49 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Wed, Jun 23, 2021 at 12:58:53PM +0200, Matteo Croce wrote: > > +void inc_diskseq(struct gendisk *disk) > > +{ > > + static atomic64_t diskseq; > > Please don't hide file scope variables in functions. > I just didn't want to clobber that file namespace, as that is the only point where it's used. > Can you explain a little more why we need a global sequence count vs > a per-disk one here? The point of the whole series is to have an unique sequence number for all the disks. Events can arrive to the userspace delayed or out-of-order, so this helps to correlate events to the disk. It might seem strange, but there isn't a way to do this yet, so I come up with a global, monotonically incrementing number. -- per aspera ad upstream