RFR(two-liner): 8212707: GlobalCounter padding is too optimistic

[Claes Redestad]

Looks good to me, and as you imply in the comments the 
DEFAULT_CACHE_LINE_SIZE should be 64 on x86_64

/Claes

On 2018-10-22 13:06, Robbin Ehn wrote:
> Hi all, please review.
>
> We should not divide DEFAULT_CACHE_LINE_SIZE by 2.
> More info in issue:
> https://bugs.openjdk.java.net/browse/JDK-8212707
>
> Code: below
>
> Sanity with T1.
>
> Thanks, Robbin
>
> diff -r bca2b63dd839 src/hotspot/share/utilities/globalCounter.hpp
> --- a/src/hotspot/share/utilities/globalCounter.hpp    Mon Oct 22 
> 14:08:07 2018 +0800
> +++ b/src/hotspot/share/utilities/globalCounter.hpp    Mon Oct 22 
> 11:48:17 2018 +0200
> @@ -48,1 +48,1 @@
> -    DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE/2, 0);
> +    DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, 0);
> @@ -50,1 +50,1 @@
> -    DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE/2, 
> sizeof(volatile uintx));
> +    DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile 
> uintx));