* Peter Xu (pet...@redhat.com) wrote:
> kvm_physical_sync_dirty_bitmap() calculates the ramblock offset in an
> awkward way from the MemoryRegionSection that passed in from the
> caller. The truth is for each KVMSlot the ramblock offset never
> change for the lifecycle. Cache the ramblock offset for each KVMSlot
> into the structure when the KVMSlot is created.
>
> With that, we can further simplify kvm_physical_sync_dirty_bitmap()
> with a helper to sync KVMSlot dirty bitmap to the ramblock dirty
> bitmap of a specific KVMSlot.
>
> Signed-off-by: Peter Xu <pet...@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> accel/kvm/kvm-all.c | 37 +++++++++++++++++--------------------
> include/sysemu/kvm_int.h | 2 ++
> 2 files changed, 19 insertions(+), 20 deletions(-)
>
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 608216fd53..f81e7a644b 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -515,15 +515,12 @@ static void kvm_log_stop(MemoryListener *listener,
> }
>
> /* get kvm's dirty pages bitmap and update qemu's */
> -static int kvm_get_dirty_pages_log_range(MemoryRegionSection *section,
> - unsigned long *bitmap)
> +static void kvm_slot_sync_dirty_pages(KVMSlot *slot)
> {
> - ram_addr_t start = section->offset_within_region +
> - memory_region_get_ram_addr(section->mr);
> - ram_addr_t pages = int128_get64(section->size) /
> qemu_real_host_page_size;
> + ram_addr_t start = slot->ram_start_offset;
> + ram_addr_t pages = slot->memory_size / qemu_real_host_page_size;
>
> - cpu_physical_memory_set_dirty_lebitmap(bitmap, start, pages);
> - return 0;
> + cpu_physical_memory_set_dirty_lebitmap(slot->dirty_bmap, start, pages);
> }
>
> #define ALIGN(x, y) (((x)+(y)-1) & ~((y)-1))
> @@ -582,12 +579,10 @@ static void
> kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
> KVMState *s = kvm_state;
> KVMSlot *mem;
> hwaddr start_addr, size;
> - hwaddr slot_size, slot_offset = 0;
> + hwaddr slot_size;
>
> size = kvm_align_section(section, &start_addr);
> while (size) {
> - MemoryRegionSection subsection = *section;
> -
> slot_size = MIN(kvm_max_slot_size, size);
> mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
> if (!mem) {
> @@ -596,12 +591,7 @@ static void
> kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
> }
>
> kvm_slot_get_dirty_log(s, mem);
> -
> - subsection.offset_within_region += slot_offset;
> - subsection.size = int128_make64(slot_size);
> - kvm_get_dirty_pages_log_range(&subsection, mem->dirty_bmap);
> -
> - slot_offset += slot_size;
> + kvm_slot_sync_dirty_pages(mem);
> start_addr += slot_size;
> size -= slot_size;
> }
> @@ -1023,7 +1013,8 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
> int err;
> MemoryRegion *mr = section->mr;
> bool writeable = !mr->readonly && !mr->rom_device;
> - hwaddr start_addr, size, slot_size;
> + hwaddr start_addr, size, slot_size, mr_offset;
> + ram_addr_t ram_start_offset;
> void *ram;
>
> if (!memory_region_is_ram(mr)) {
> @@ -1041,9 +1032,13 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
> return;
> }
>
> - /* use aligned delta to align the ram address */
> - ram = memory_region_get_ram_ptr(mr) + section->offset_within_region +
> - (start_addr - section->offset_within_address_space);
> + /* The offset of the kvmslot within the memory region */
> + mr_offset = section->offset_within_region + start_addr -
> + section->offset_within_address_space;
> +
> + /* use aligned delta to align the ram address and offset */
> + ram = memory_region_get_ram_ptr(mr) + mr_offset;
> + ram_start_offset = memory_region_get_ram_addr(mr) + mr_offset;
>
> kvm_slots_lock(kml);
>
> @@ -1082,6 +1077,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
> mem->as_id = kml->as_id;
> mem->memory_size = slot_size;
> mem->start_addr = start_addr;
> + mem->ram_start_offset = ram_start_offset;
> mem->ram = ram;
> mem->flags = kvm_mem_flags(mr);
> kvm_slot_init_dirty_bitmap(mem);
> @@ -1092,6 +1088,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
> abort();
> }
> start_addr += slot_size;
> + ram_start_offset += slot_size;
> ram += slot_size;
> size -= slot_size;
> } while (size);
> diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h
> index 4434e15ec7..1a19bfef80 100644
> --- a/include/sysemu/kvm_int.h
> +++ b/include/sysemu/kvm_int.h
> @@ -25,6 +25,8 @@ typedef struct KVMSlot
> unsigned long *dirty_bmap;
> /* Cache of the address space ID */
> int as_id;
> + /* Cache of the offset in ram address space */
> + ram_addr_t ram_start_offset;
> } KVMSlot;
>
> typedef struct KVMMemoryListener {
> --
> 2.24.1
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
