* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> We record the address of the dirty pages that received,
> it will help flushing pages that cached into SVM.
> We record them by re-using migration dirty bitmap.
>
> Cc: Juan Quintela <quint...@redhat.com>
> Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
> Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> migration/ram.c | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index b588990..ed3b606 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -2231,6 +2231,9 @@ static inline void *host_from_ram_block_offset(RAMBlock
> *block,
> static inline void *colo_cache_from_block_offset(RAMBlock *block,
> ram_addr_t offset)
> {
> + unsigned long *bitmap;
> + long k;
You could use a better name than 'k'.
Dave
> if (!offset_in_ramblock(block, offset)) {
> return NULL;
> }
> @@ -2239,6 +2242,17 @@ static inline void
> *colo_cache_from_block_offset(RAMBlock *block,
> __func__, block->idstr);
> return NULL;
> }
> +
> + k = (memory_region_get_ram_addr(block->mr) + offset) >> TARGET_PAGE_BITS;
> + bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
> + /*
> + * During colo checkpoint, we need bitmap of these migrated pages.
> + * It help us to decide which pages in ram cache should be flushed
> + * into VM's RAM later.
> + */
> + if (!test_and_set_bit(k, bitmap)) {
> + migration_dirty_pages++;
> + }
> return block->colo_cache + offset;
> }
>
> @@ -2664,6 +2678,7 @@ static int ram_load(QEMUFile *f, void *opaque, int
> version_id)
> int colo_init_ram_cache(void)
> {
> RAMBlock *block;
> + int64_t ram_cache_pages = last_ram_offset() >> TARGET_PAGE_BITS;
>
> rcu_read_lock();
> QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
> @@ -2678,6 +2693,15 @@ int colo_init_ram_cache(void)
> }
> rcu_read_unlock();
> ram_cache_enable = true;
> + /*
> + * Record the dirty pages that sent by PVM, we use this dirty bitmap
> together
> + * with to decide which page in cache should be flushed into SVM's RAM.
> Here
> + * we use the same name 'migration_bitmap_rcu' as for migration.
> + */
> + migration_bitmap_rcu = g_new0(struct BitmapRcu, 1);
> + migration_bitmap_rcu->bmap = bitmap_new(ram_cache_pages);
> + migration_dirty_pages = 0;
> +
> return 0;
>
> out_locked:
> @@ -2695,9 +2719,15 @@ out_locked:
> void colo_release_ram_cache(void)
> {
> RAMBlock *block;
> + struct BitmapRcu *bitmap = migration_bitmap_rcu;
>
> ram_cache_enable = false;
>
> + atomic_rcu_set(&migration_bitmap_rcu, NULL);
> + if (bitmap) {
> + call_rcu(bitmap, migration_bitmap_free, rcu);
> + }
> +
> rcu_read_lock();
> QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
> if (block->colo_cache) {
> --
> 1.8.3.1
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
