On Tue, May 18, 2021 at 12:06:13PM +0300, Mike Rapoport wrote: > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > When unused memory map is freed the preserved part of the memory map is > extended to match pageblock boundaries because lots of core mm > functionality relies on homogeneity of the memory map within pageblock > boundaries. > > Since pfn_valid() is used to check whether there is a valid memory map > entry for a PFN, make it return true also for PFNs that have memory map > entries even if there is no actual memory populated there. I thought pfn_valid() was a particularly hot path... do we really want to be doing multiple lookups here? Is there no better solution? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
