[dpdk-dev] [PATCH v7 02/10] eal: add power management intrinsics

[Ferruh Yigit]

On 10/15/2020 1:04 PM, Anatoly Burakov wrote:
> From: Liang Ma <liang.j.ma at intel.com>
> 
> Add two new power management intrinsics, and provide an implementation
> in eal/x86 based on UMONITOR/UMWAIT instructions. The instructions
> are implemented as raw byte opcodes because there is not yet widespread
> compiler support for these instructions.
> 
> The power management instructions provide an architecture-specific
> function to either wait until a specified TSC timestamp is reached, or
> optionally wait until either a TSC timestamp is reached or a memory
> location is written to. The monitor function also provides an optional
> comparison, to avoid sleeping when the expected write has already
> happened, and no more writes are expected.
> 
> For more details, please refer to Intel(R) 64 and IA-32 Architectures
> Software Developer's Manual, Volume 2.
> 
> Signed-off-by: Liang Ma <liang.j.ma at intel.com>
> Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
> Acked-by: David Christensen <drc at linux.vnet.ibm.com>
> ---
> 
> Notes:
>      v7:
>      - Fix code style and other nitpicks (Konstantin)
>      v6:
>      - Add spinlock-enabled version to allow pthread-wait-like
>        constructs with umwait
>      - Clarify comments
>      - Added experimental tags to intrinsics
>      - Added endianness support
>      v5:
>      - Removed return values
>      - Simplified intrinsics and hardcoded C0.2 state
>      - Added other arch stubs
> 

Hi Ruifeng,

This is the patch we have talked in today's release status meeting, can you 
please check the patch from Arm perspective?
Since the instructions are not supported by Arm I expect it should be OK but it 
would be good to get your ack to proceed.

Thanks,
ferruh