* Stefan Hajnoczi (stefa...@redhat.com) wrote:
> The dirty memory bitmap is managed by ram_addr.h and copied to
> migration_bitmap[] periodically during live migration.
>
> Move the code to sync the bitmap to ram_addr.h where related code lives.
Is this sync code going to need to gain a barrier (although I'm not quite
sure which) to ensure it's picked up all changes?
Dave
>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> arch_init.c | 46 ++--------------------------------------------
> include/exec/ram_addr.h | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 46 insertions(+), 44 deletions(-)
>
> diff --git a/arch_init.c b/arch_init.c
> index 7680d28..79c7784 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -436,52 +436,10 @@ ram_addr_t
> migration_bitmap_find_and_reset_dirty(MemoryRegion *mr,
> return (next - base) << TARGET_PAGE_BITS;
> }
>
> -static inline bool migration_bitmap_set_dirty(ram_addr_t addr)
> -{
> - bool ret;
> - int nr = addr >> TARGET_PAGE_BITS;
> -
> - ret = test_and_set_bit(nr, migration_bitmap);
> -
> - if (!ret) {
> - migration_dirty_pages++;
> - }
> - return ret;
> -}
> -
> static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length)
> {
> - ram_addr_t addr;
> - unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
> -
> - /* start address is aligned at the start of a word? */
> - if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) {
> - int k;
> - int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
> - unsigned long *src = ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION];
> -
> - for (k = page; k < page + nr; k++) {
> - if (src[k]) {
> - unsigned long new_dirty;
> - new_dirty = ~migration_bitmap[k];
> - migration_bitmap[k] |= src[k];
> - new_dirty &= src[k];
> - migration_dirty_pages += ctpopl(new_dirty);
> - src[k] = 0;
> - }
> - }
> - } else {
> - for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
> - if (cpu_physical_memory_get_dirty(start + addr,
> - TARGET_PAGE_SIZE,
> - DIRTY_MEMORY_MIGRATION)) {
> - cpu_physical_memory_reset_dirty(start + addr,
> - TARGET_PAGE_SIZE,
> - DIRTY_MEMORY_MIGRATION);
> - migration_bitmap_set_dirty(start + addr);
> - }
> - }
> - }
> + migration_dirty_pages +=
> + cpu_physical_memory_sync_dirty_bitmap(migration_bitmap, start,
> length);
> }
>
>
> diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
> index ba90daa..87a8b28 100644
> --- a/include/exec/ram_addr.h
> +++ b/include/exec/ram_addr.h
> @@ -190,5 +190,49 @@ static inline void
> cpu_physical_memory_clear_dirty_range(ram_addr_t start,
> void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t length,
> unsigned client);
>
> +static inline
> +uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
> + ram_addr_t start,
> + ram_addr_t length)
> +{
> + ram_addr_t addr;
> + unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
> + uint64_t num_dirty = 0;
> +
> + /* start address is aligned at the start of a word? */
> + if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) {
> + int k;
> + int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
> + unsigned long *src = ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION];
> +
> + for (k = page; k < page + nr; k++) {
> + if (src[k]) {
> + unsigned long new_dirty;
> + new_dirty = ~dest[k];
> + dest[k] |= src[k];
> + new_dirty &= src[k];
> + num_dirty += ctpopl(new_dirty);
> + src[k] = 0;
> + }
> + }
> + } else {
> + for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
> + if (cpu_physical_memory_get_dirty(start + addr,
> + TARGET_PAGE_SIZE,
> + DIRTY_MEMORY_MIGRATION)) {
> + cpu_physical_memory_reset_dirty(start + addr,
> + TARGET_PAGE_SIZE,
> + DIRTY_MEMORY_MIGRATION);
> + long k = (start + addr) >> TARGET_PAGE_BITS;
> + if (!test_and_set_bit(k, dest)) {
> + num_dirty++;
> + }
> + }
> + }
> + }
> +
> + return num_dirty;
> +}
> +
> #endif
> #endif
> --
> 2.1.0
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
