Re: [Qemu-devel] [PATCH 5/8] Only calculate expected_time for stage 2

[Orit Wasserman]

On 06/22/2012 04:46 PM, Juan Quintela wrote:
> ram_save_remaining() is an expensive operation when there is a lot of memory.
> So we only call the function when we need it.
> 
> Signed-off-by: Juan Quintela <address@hidden>
> ---
>  arch_init.c |   10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/arch_init.c b/arch_init.c
> index a9e8b74..424efe7 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -299,7 +299,6 @@ int ram_save_live(QEMUFile *f, int stage, void *opaque)
>      ram_addr_t addr;
>      uint64_t bytes_transferred_last;
>      double bwidth = 0;
> -    uint64_t expected_time = 0;
>      int ret;
> 
>      if (stage < 0) {
> @@ -376,9 +375,12 @@ int ram_save_live(QEMUFile *f, int stage, void *opaque)
> 
>      qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
> 
> -    expected_time = ram_save_remaining() * TARGET_PAGE_SIZE / bwidth;
> -
> -    return (stage == 2) && (expected_time <= migrate_max_downtime());
> +    if (stage == 2) {
> +        uint64_t expected_time;
> +        expected_time = ram_save_remaining() * TARGET_PAGE_SIZE / bwidth;
> +        return expected_time <= migrate_max_downtime();
> +    }
> +    return 0;
>  }
> 
>  static inline void *host_from_stream_offset(QEMUFile *f,
Reviewed-by: Orit Wasserman <address@hidden>