From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [Patch 2 of 2]: PV-domain SMP performance Linux-part
Date: Thu, 18 Dec 2008 07:41:57 +0000
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To: Juergen Gross <juergen.gross@fujitsu-siemens.com>
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>>> Juergen Gross <juergen.gross@fujitsu-siemens.com> 18.12.08 08:18 >>>
>Jan Beulich wrote:
>>=20
>>> +		_vcpu->no_desched =3D 0;					=
\
>>> +	        _vcpu->evtchn_upcall_mask =3D 0;				=
\
>>> 		barrier(); /* unmask then check (avoid races) */	\
>>> +		if ( unlikely(_vcpu->desched_delay) )			\
>>> +			(void)((HYPERVISOR_sched_op(SCHEDOP_yield, =
_vcpu))?:0); \
>>=20
>> Why not just cast the function result to void? Likewise further =
below...
>
>I took that from include/xen/hypercall.h, which mentioned problems with =
just
>casting the function result.

Ah, yes, I recall. But then why don't you use that macro? After all, =
hypercall.h
must have been included if you're able to call HYPERVISOR_sched_op().

Jan