On 12/14/2017 12:09 AM, Tejun Heo wrote: > Hello, > > On Wed, Dec 13, 2017 at 11:05:11AM +0800, jianchao.wang wrote: >> Just don't quite understand the strict definition of "generation" you said. >> A allocation->free cycle is a generation ? or a idle->in-flight cycle is a >> generation? The idle->in-flight cycle could include the requeue case as >> above. >> Can you clarify this? > > So, a request is > > * IN_FLIGHT, if it can be completed by the lower level driver > > * COMPLETE, if the lower level driver indicated completion but block > layer is still processing. > > * IDLE, if neither of the above two. > > and generation is bumped up on IDLE -> IN_FLIGHT to distinguish > different IN_FLIGHT instances. >
So a generation means a cycle from IDLE -> IN_FLIGHT. Thanks for your response. That's really appreciated. Jianchao > Thanks. >
