On 28.06.2021 13:10, Olaf Hering wrote: > Am Mon, 28 Jun 2021 09:48:26 +0200 > schrieb Jan Beulich <[email protected]>: > >> On 25.06.2021 18:36, Andrew Cooper wrote: >>> This is an external interface, and I'm not sure it will tolerate finding >>> more than p2m_size allegedly dirty. >> But you do realize that a few lines down from here there already was >> policy_stats->dirty_count = -1; >> ? Or are you trying to tell me that -1 (documented as indicating >> "unknown") is okay on subsequent iterations, but not on the first one? > > precopy_policy() gets called twice during each iteration. > Last time I tried to use this API it was difficult to work with. > It is required to look at dirty_count and iteration to see the actual state. > Maybe it was just me who initially failed to fully understand the intent. > > I think as it is right now, the first run with iteration being zero is > the only way to know the actual p2m_size, in case the consumer really > wants to know this detail.
But if a field named dirty_count was intended to convey the P2M size (and then only on the first iteration), this very certainly would have needed writing down somewhere. Jan
