Thanks, I didn't notice this case.
On Sun, Jul 14, 2019 at 10:51:19PM +0800, Ivan Ren wrote:
>Reproduce the problem:
>migrate
>migrate_cancel
>migrate
>
>Error happen for memory migration
>
>The reason as follows:
>1. qemu start, ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] all set to
> 1 by a series of cpu_physical_memory_set_dirty_range
>2. migration start:ram_init_bitmaps
> - memory_global_dirty_log_start: begin log diry
s/diry/dirty/
> - memory_global_dirty_log_sync: sync dirty bitmap to
> ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]
> - migration_bitmap_sync_range: sync ram_list.
> dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap
> and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero
>3. migration data...
>4. migrate_cancel, will stop log dirty
>5. migration start:ram_init_bitmaps
> - memory_global_dirty_log_start: begin log diry
same as above
> - memory_global_dirty_log_sync: sync dirty bitmap to
> ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]
> - migration_bitmap_sync_range: sync ram_list.
> dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap
> and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero
>
> Here RAMBlock.bmap only have new logged dirty pages, don't contain
> the whole guest pages.
>
>Signed-off-by: Ivan Ren <ivan...@tencent.com>
>---
> migration/ram.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
>
>diff --git a/migration/ram.c b/migration/ram.c
>index 908517fc2b..bbebaee0c1 100644
>--- a/migration/ram.c
>+++ b/migration/ram.c
>@@ -3173,11 +3173,11 @@ static int ram_state_init(RAMState **rsp)
> QSIMPLEQ_INIT(&(*rsp)->src_page_requests);
>
> /*
>+ * Count the total number of pages used by ram blocks not including any
>+ * gaps due to alignment or unplugs.
> * This must match with the initial values of dirty bitmap.
>- * Currently we initialize the dirty bitmap to all zeros so
>- * here the total dirty page count is zero.
> */
>- (*rsp)->migration_dirty_pages = 0;
>+ (*rsp)->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
> ram_state_reset(*rsp);
>
> return 0;
>@@ -3196,12 +3196,13 @@ static void ram_list_init_bitmaps(void)
> * The initial dirty bitmap for migration must be set with all
> * ones to make sure we'll migrate every guest RAM page to
> * destination.
>- * Here we didn't set RAMBlock.bmap simply because it is already
>- * set in ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] in
>- * ram_block_add, and that's where we'll sync the dirty bitmaps.
>- * Here setting RAMBlock.bmap would be fine too but not necessary.
>+ * Here we set RAMBlock.bmap all to 1 because when rebegin a
>+ * new migration after a failed migration, ram_list.
It is after failure or cancel?
>+ * dirty_memory[DIRTY_MEMORY_MIGRATION] don't include the whole
>+ * guest memory.
> */
> block->bmap = bitmap_new(pages);
>+ bitmap_set(block->bmap, 0, pages);
> if (migrate_postcopy_ram()) {
> block->unsentmap = bitmap_new(pages);
> bitmap_set(block->unsentmap, 0, pages);
>--
>2.17.2 (Apple Git-113)
>
Reviewed-by: Wei Yang <richardw.y...@linux.intel.com>
--
Wei Yang
Help you, Help me
