> -----Original Message----- > From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx] > Sent: Friday, April 7, 2017 04:27 > To: devel@xxxxxxxxxxxxxxxxxxxxxx; x86@xxxxxxxxxx > Cc: 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>; Steven > Rostedt <rostedt@xxxxxxxxxxx>; Jork Loeser <Jork.Loeser@xxxxxxxxxxxxx> > Subject: [PATCH 2/7] x86/hyper-v: fast hypercall implementation > diff --git a/arch/x86/include/asm/mshyperv.h > b/arch/x86/include/asm/mshyperv.h index 331e834..9a5f58b 100644 > --- a/arch/x86/include/asm/mshyperv.h > +++ b/arch/x86/include/asm/mshyperv.h > @@ -216,6 +216,43 @@ static inline u64 hv_do_hypercall(u64 control, void > *input, void *output) #endif /* !x86_64 */ } > > +/* Fast hypercall with 8 bytes of input and no output */ static inline > +u64 hv_do_fast_hypercall8(u16 code, u64 input1) { > + union hv_hypercall_input control = {0}; > + > + control.code = code; > + control.fast = 1; > +#ifdef CONFIG_X86_64 > + { > + u64 hv_status; > + > + __asm__ __volatile__("call *%3" > + : "=a" (hv_status) > + : "c" (control.as_uint64), "d" (input1), > + "m" (hv_hypercall_pg) > + : "cc", "r8", "%r9", "%r10", "%r11"); > + return hv_status; Clobber memory (are there such fast hypercalls)? > + } > +#else > + { > + u32 hv_status_hi, hv_status_lo; > + > + __asm__ __volatile__ ("call *%6" > + : "=d"(hv_status_hi), > + "=a"(hv_status_lo) : > + "d" (control.as_uint32_hi), > + "a" (control.as_uint32_lo), > + "c" ((u32)input1), > + "b" ((u32)(input1 >> 32)), > + "m" (hv_hypercall_pg) > + : "cc"); > + > + return hv_status_lo | ((u64)hv_status_hi << 32); > + } > +#endif Please clobber ECX, EDI and ESI for x86. Clobber memory as well? _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
