Re: [Qemu-devel] [PATCH 46/51] ram: Remember last_page instead of last_offset

[Dr. David Alan Gilbert]

* Juan Quintela (address@hidden) wrote:
> Signed-off-by: Juan Quintela <address@hidden>
> ---
>  migration/ram.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index b1a031e..57b776b 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -171,8 +171,8 @@ struct RAMState {
>      RAMBlock *last_seen_block;
>      /* Last block from where we have sent data */
>      RAMBlock *last_sent_block;
> -    /* Last offset we have sent data from */
> -    ram_addr_t last_offset;
> +    /* Last dirty page we have sent */

Can you make that 'Last dirty target page we have sent' 
just so we know which shape page we're dealing with.

> +    ram_addr_t last_page;
>      /* last ram version we have seen */
>      uint32_t last_version;
>      /* We are in the first round */
> @@ -1063,7 +1063,7 @@ static bool find_dirty_block(RAMState *rs, 
> PageSearchStatus *pss,
>      pss->offset = migration_bitmap_find_dirty(rs, pss->block, pss->offset,
>                                                page);
>      if (pss->complete_round && pss->block == rs->last_seen_block &&
> -        pss->offset >= rs->last_offset) {
> +        pss->offset >= rs->last_page) {

That's odd; isn't pss->offset still in bytes?

Dave

>          /*
>           * We've been once around the RAM and haven't found anything.
>           * Give up.
> @@ -1396,7 +1396,7 @@ static int ram_find_and_save_block(RAMState *rs, bool 
> last_stage)
>      }
>  
>      pss.block = rs->last_seen_block;
> -    pss.offset = rs->last_offset;
> +    pss.offset = rs->last_page << TARGET_PAGE_BITS;
>      pss.complete_round = false;
>  
>      if (!pss.block) {
> @@ -1418,7 +1418,7 @@ static int ram_find_and_save_block(RAMState *rs, bool 
> last_stage)
>      } while (!pages && again);
>  
>      rs->last_seen_block = pss.block;
> -    rs->last_offset = pss.offset;
> +    rs->last_page = pss.offset >> TARGET_PAGE_BITS;
>  
>      return pages;
>  }
> @@ -1493,7 +1493,7 @@ static void ram_state_reset(RAMState *rs)
>  {
>      rs->last_seen_block = NULL;
>      rs->last_sent_block = NULL;
> -    rs->last_offset = 0;
> +    rs->last_page = 0;
>      rs->last_version = ram_list.version;
>      rs->ram_bulk_stage = true;
>  }
> @@ -1838,7 +1838,7 @@ static int postcopy_chunk_hostpages(MigrationState *ms)
>      /* Easiest way to make sure we don't resume in the middle of a host-page 
> */
>      rs->last_seen_block = NULL;
>      rs->last_sent_block = NULL;
> -    rs->last_offset     = 0;
> +    rs->last_page = 0;
>  
>      QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
>          unsigned long first = block->offset >> TARGET_PAGE_BITS;
> -- 
> 2.9.3
> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK