Re: [PATCH RFC 13/21] migration: Add migration_ram_pagesize_largest()

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Peter Xu (peterx@redhat.com) wrote:
> Let it replace the old qemu_ram_pagesize_largest() just to fetch the page
> sizes using migration_ram_pagesize(), because it'll start to consider
> double mapping effect in migrations.
> 
> Also don't account the ignored ramblocks as they won't be migrated.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> ---
>  include/exec/cpu-common.h |  1 -
>  migration/migration.c     |  2 +-
>  migration/ram.c           | 12 ++++++++++++
>  migration/ram.h           |  1 +
>  softmmu/physmem.c         | 13 -------------
>  5 files changed, 14 insertions(+), 15 deletions(-)
> 
> diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
> index 94452aa17f..4c394ccdfc 100644
> --- a/include/exec/cpu-common.h
> +++ b/include/exec/cpu-common.h
> @@ -96,7 +96,6 @@ int qemu_ram_get_fd(RAMBlock *rb);
>  
>  size_t qemu_ram_pagesize(RAMBlock *block);
>  bool qemu_ram_is_hugetlb(RAMBlock *rb);
> -size_t qemu_ram_pagesize_largest(void);
>  
>  /**
>   * cpu_address_space_init:
> diff --git a/migration/migration.c b/migration/migration.c
> index f6fe474fc3..7724e00c47 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -604,7 +604,7 @@ process_incoming_migration_co(void *opaque)
>  
>      assert(mis->from_src_file);
>      mis->migration_incoming_co = qemu_coroutine_self();
> -    mis->largest_page_size = qemu_ram_pagesize_largest();
> +    mis->largest_page_size = migration_ram_pagesize_largest();
>      postcopy_state_set(POSTCOPY_INCOMING_NONE);
>      migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
>                        MIGRATION_STATUS_ACTIVE);
> diff --git a/migration/ram.c b/migration/ram.c
> index 945c6477fd..2ebf414f5f 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -135,6 +135,18 @@ size_t migration_ram_pagesize(RAMBlock *block)
>      return qemu_ram_pagesize(block);
>  }
>  
> +size_t migration_ram_pagesize_largest(void)
> +{
> +    RAMBlock *block;
> +    size_t largest = 0;
> +
> +    RAMBLOCK_FOREACH_NOT_IGNORED(block) {
> +        largest = MAX(largest, migration_ram_pagesize(block));
> +    }
> +
> +    return largest;
> +}
> +
>  static void XBZRLE_cache_lock(void)
>  {
>      if (migrate_use_xbzrle()) {
> diff --git a/migration/ram.h b/migration/ram.h
> index 162b3e7cb8..cefe166841 100644
> --- a/migration/ram.h
> +++ b/migration/ram.h
> @@ -69,6 +69,7 @@ bool ramblock_is_ignored(RAMBlock *block);
>  
>  int xbzrle_cache_resize(uint64_t new_size, Error **errp);
>  size_t migration_ram_pagesize(RAMBlock *block);
> +size_t migration_ram_pagesize_largest(void);
>  uint64_t ram_bytes_remaining(void);
>  uint64_t ram_bytes_total(void);
>  void mig_throttle_counter_reset(void);
> diff --git a/softmmu/physmem.c b/softmmu/physmem.c
> index cdda7eaea5..536c204811 100644
> --- a/softmmu/physmem.c
> +++ b/softmmu/physmem.c
> @@ -1813,19 +1813,6 @@ bool qemu_ram_is_hugetlb(RAMBlock *rb)
>      return rb->page_size > qemu_real_host_page_size();
>  }
>  
> -/* Returns the largest size of page in use */
> -size_t qemu_ram_pagesize_largest(void)
> -{
> -    RAMBlock *block;
> -    size_t largest = 0;
> -
> -    RAMBLOCK_FOREACH(block) {
> -        largest = MAX(largest, qemu_ram_pagesize(block));
> -    }
> -
> -    return largest;
> -}
> -
>  static int memory_try_enable_merging(void *addr, size_t len)
>  {
>      if (!machine_mem_merge(current_machine)) {
> -- 
> 2.37.3
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK