On Tue, Jun 11, 2019 at 10:56:42PM -0400, John Dorminy wrote: > I believe the second of these might, but is not guaranteed to, > preserve the first error observed in a child; I believe if you want to > definitely save the first error you need an atomic. Is there any reason not to simply use a cmpxchg? Yes, it is a relatively expensive operation, but once we are chaining bios we are out of the super hot path anyway. We do something similar in xfs and iomap already.
