Re: [PATCH 3/3] arm: extend pfn_valid to take into accound freed memory map alignment
flat view
From: "Russell King (Oracle)" <linux@armlinux.org.uk>
Date: 2021-05-18 09:44:39
Also in:
linux-mm, lkml
On Tue, May 18, 2021 at 12:06:13PM +0300, Mike Rapoport wrote:
From: Mike Rapoport <redacted> 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! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel