Re: [PATCH RFC 03/15] migration: Enable UFFD_FEATURE_THREAD_ID even without blocktime feat

[Dr. David Alan Gilbert]

* Peter Xu (peterx@redhat.com) wrote:
> This patch allows us to read the tid even without blocktime feature enabled.
> It's useful when tracing postcopy fault thread on faulted pages to show thread
> id too with the address.
> 
> Remove the comments - they're merely not helpful at all.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>

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

> ---
>  migration/postcopy-ram.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
> index d18b5d05b2..2176ed68a5 100644
> --- a/migration/postcopy-ram.c
> +++ b/migration/postcopy-ram.c
> @@ -283,15 +283,13 @@ static bool ufd_check_and_apply(int ufd, 
> MigrationIncomingState *mis)
>      }
>  
>  #ifdef UFFD_FEATURE_THREAD_ID
> -    if (migrate_postcopy_blocktime() && mis &&
> -        UFFD_FEATURE_THREAD_ID & supported_features) {
> -        /* kernel supports that feature */
> -        /* don't create blocktime_context if it exists */
> -        if (!mis->blocktime_ctx) {
> -            mis->blocktime_ctx = blocktime_context_new();
> -        }
> -
> +    if (UFFD_FEATURE_THREAD_ID & supported_features) {
>          asked_features |= UFFD_FEATURE_THREAD_ID;
> +        if (migrate_postcopy_blocktime()) {
> +            if (!mis->blocktime_ctx) {
> +                mis->blocktime_ctx = blocktime_context_new();
> +            }
> +        }
>      }
>  #endif
>  
> -- 
> 2.32.0
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK