On Tue, 23 Jun 2026 22:03:41 +0200 Boris Brezillon <[email protected]> wrote:
> Anyway, I'll try to get back to this map_pages() implementation, and > see how we can handle the fallback when locks can't be acquired in that > path (I assume this would mean no PMD mapping in the fallback path if > we get rid of huge_fault()). More on that. I had a brief look at map_pages()/fault_around(), and it seems it's only meant to populate PTE entries, not PMDs. Part of the perf boost we were looking for when adding huge_fault() was limiting the number of faults when adjacent pages are touched, but the other part was limiting the page table depth to optimize page-table walks, so if we're implementing map_pages() without huge_fault(), we basically lose the second part of the optimization. I'd need to check how much perf we leave on the table with that.
