diff --git a/qemu/exec.c b/qemu/exec.c index 8a0e26e0..5959e532 100644 --- a/qemu/exec.c +++ b/qemu/exec.c @@ -103,6 +103,7 @@ typedef struct PhysPageMap { } PhysPageMap; struct AddressSpaceDispatch { + MemoryRegionSection *mru_section; /* This is a multi-level map on the physical address space. * The bottom level has pointers to MemoryRegionSections. */ @@ -300,17 +301,28 @@ bool memory_region_is_unassigned(struct uc_struct* uc, MemoryRegion *mr) } static MemoryRegionSection *address_space_lookup_region(AddressSpaceDispatch *d, - hwaddr addr, - bool resolve_subpage) + hwaddr addr, + bool resolve_subpage) { - MemoryRegionSection *section; + MemoryRegionSection *section = atomic_read(&d->mru_section); subpage_t *subpage; + bool update; - section = phys_page_find(d->phys_map, addr, d->map.nodes, d->map.sections); + if (section && section != &d->map.sections[PHYS_SECTION_UNASSIGNED] && + section_covers_addr(section, addr)) { + update = false; + } else { + section = phys_page_find(d->phys_map, addr, d->map.nodes, + d->map.sections); + update = true; + } if (resolve_subpage && section->mr->subpage) { subpage = container_of(section->mr, subpage_t, iomem); section = &d->map.sections[subpage->sub_section[SUBPAGE_IDX(addr)]]; } + if (update) { + atomic_set(&d->mru_section, section); + } return section; }