* Peter Xu (peterx@redhat.com) wrote:
> We used to do off-by-one fixup for pss->page when finished one host huge page
> transfer. That seems to be unnecesary at all. Drop it.
>
> Cc: Keqian Zhu <zhukeqian1@huawei.com>
> Cc: Kunkun Jiang <jiangkunkun@huawei.com>
> Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
Yes, I think so - I guess the -1 and +1 cancel so it works, and in
practice ram_save_host_page then points to 1 page inside the hugepage
which is then always clean (because it just sent it) so probably
survives.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
> migration/ram.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 5234d1ece1..381ad56d26 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1611,7 +1611,7 @@ static int ram_save_release_protection(RAMState *rs, PageSearchStatus *pss,
> /* Check if page is from UFFD-managed region. */
> if (pss->block->flags & RAM_UF_WRITEPROTECT) {
> void *page_address = pss->block->host + (start_page << TARGET_PAGE_BITS);
> - uint64_t run_length = (pss->page - start_page + 1) << TARGET_PAGE_BITS;
> + uint64_t run_length = (pss->page - start_page) << TARGET_PAGE_BITS;
>
> /* Flush async buffers before un-protect. */
> qemu_fflush(rs->f);
> @@ -2230,7 +2230,7 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss,
> offset_in_ramblock(pss->block,
> ((ram_addr_t)pss->page) << TARGET_PAGE_BITS));
> /* The offset we leave with is the min boundary of host page and block */
> - pss->page = MIN(pss->page, hostpage_boundary) - 1;
> + pss->page = MIN(pss->page, hostpage_boundary);
>
> res = ram_save_release_protection(rs, pss, start_page);
> return (res < 0 ? res : pages);
> --
> 2.32.0
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK