RE: [PATCH 2/4] x86/hyper-v: use 'fast' hypercall for HVCALL_SEND_IPI

[Michael Kelley (EOSG)]

> -----Original Message-----
> From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> Sent: Friday, June 22, 2018 10:06 AM
> To: x86@xxxxxxxxxx
> Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; KY Srinivasan
> <kys@xxxxxxxxxxxxx>; Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>; Stephen Hemminger
> <sthemmin@xxxxxxxxxxxxx>; Thomas Gleixner <tglx@xxxxxxxxxxxxx>; Ingo Molnar
> <mingo@xxxxxxxxxx>; H. Peter Anvin <hpa@xxxxxxxxx>; Tianyu Lan
> <Tianyu.Lan@xxxxxxxxxxxxx>; Michael Kelley (EOSG) <Michael.H.Kelley@xxxxxxxxxxxxx>
> Subject: [PATCH 2/4] x86/hyper-v: use 'fast' hypercall for HVCALL_SEND_IPI
> 
> Current Hyper-V TLFS (v5.0b) claims that HvCallSendSyntheticClusterIpi
> hypercall can't be 'fast' (passing parameters through registers) but
> apparently this is not true, Windows always uses 'fast' version. We can
> do the same in Linux too.
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>