On 07/04/2012 01:15 PM, Caraman Mihai Claudiu-B02008 wrote: >> ________________________________________ >> From: Alexander Graf [agraf@xxxxxxx] >> Sent: Wednesday, July 04, 2012 6:45 PM >> To: Caraman Mihai Claudiu-B02008 >> Cc: <kvm-ppc@xxxxxxxxxxxxxxx>; KVM list; linuxppc-dev; qemu-ppc@xxxxxxxxxx List; Benjamin Herrenschmidt >> Subject: Re: [Qemu-ppc] [RFC PATCH 12/17] PowerPC: booke64: Add DO_KVM kernel hooks >> >> On 04.07.2012, at 17:27, Caraman Mihai Claudiu-B02008 wrote: >> >>>> -----Original Message----- >>>> From: Alexander Graf [mailto:agraf@xxxxxxx] >>>> Sent: Wednesday, July 04, 2012 5:30 PM >>>> To: Caraman Mihai Claudiu-B02008 >>>> Cc: <kvm-ppc@xxxxxxxxxxxxxxx>; KVM list; linuxppc-dev; qemu- >>>> ppc@xxxxxxxxxx List; Benjamin Herrenschmidt >>>> Subject: Re: [Qemu-ppc] [RFC PATCH 12/17] PowerPC: booke64: Add DO_KVM >>>> kernel hooks >>>> >>>> >>>> On 25.06.2012, at 14:26, Mihai Caraman wrote: >>>> >>>>> Hook DO_KVM macro to 64-bit booke in a optimal way similar to 32-bit >>>> booke >>>>> see head_fsl_booke.S file. Extend interrupt handlers' parameter list >>>> with >>>>> interrupt vector numbers to accomodate the macro. Rework Guest Doorbell >>>>> handler to use the proper GSRRx save/restore registers. >>>>> Only the bolted version of tlb miss handers is addressed now. >>>>> >>>>> Signed-off-by: Mihai Caraman <mihai.caraman@xxxxxxxxxxxxx> >>>>> --- >>>>> arch/powerpc/kernel/exceptions-64e.S | 114 ++++++++++++++++++++++++--- >>>> ------- >>>>> arch/powerpc/mm/tlb_low_64e.S | 14 +++- >>>>> 2 files changed, 92 insertions(+), 36 deletions(-) >>>>> >>>>> diff --git a/arch/powerpc/kernel/exceptions-64e.S >>>> b/arch/powerpc/kernel/exceptions-64e.S >>>>> index 06f7aec..a60f81f 100644 >>>>> --- a/arch/powerpc/kernel/exceptions-64e.S >>>>> +++ b/arch/powerpc/kernel/exceptions-64e.S >>>>> @@ -25,6 +25,8 @@ >>>>> #include <asm/ppc-opcode.h> >>>>> #include <asm/mmu.h> >>>>> #include <asm/hw_irq.h> >>>>> +#include <asm/kvm_asm.h> >>>>> +#include <asm/kvm_booke_hv_asm.h> >>>>> >>>>> /* XXX This will ultimately add space for a special exception save >>>>> * structure used to save things like SRR0/SRR1, SPRGs, MAS, etc... >>>>> @@ -34,13 +36,24 @@ >>>>> */ >>>>> #define SPECIAL_EXC_FRAME_SIZE INT_FRAME_SIZE >>>>> >>>>> +#ifdef CONFIG_KVM_BOOKE_HV >>>>> +#define KVM_BOOKE_HV_MFSPR(reg, spr) \ >>>>> + BEGIN_FTR_SECTION \ >>>>> + mfspr reg, spr; \ >>>>> + END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) >>>>> +#else >>>>> +#define KVM_BOOKE_HV_MFSPR(reg, spr) >>>>> +#endif >>>> >>>> Bleks - this is ugly. >>> >>> I agree :) But I opted to keep the optimizations done for 32-bit. >>> >>>> Do we really need to open-code the #ifdef here? >>> >>> 32-bit implementation fortunately use asm macros, we can't nest defines. >>> >>>> Can't the feature section code determine that the feature is disabled and >>>> just always not include the code? >>> >>> CPU_FTR_EMB_HV is set even if KVM is not configured. >> >> I don't get the point then. Why not have the whole DO_KVM masked under FTR_SECTION_IFSET(CPU_FTR_EMB_HV)? Are there book3s_64 implementations without HV? > > I guess you refer to book3e_64. I don't know all implementations but Embedded.HV category is optional. > >> Can't we just mfspr unconditionally in DO_KVM? > > I think Scott should better answer this question, I don't know why he opted for the other approach. That was on 32-bit, where some of DO_KVM's users want SRR1 for their own purposes. >>>>> -.macro tlb_prolog_bolted addr >>>>> +.macro tlb_prolog_bolted intnum addr >>>>> mtspr SPRN_SPRG_TLB_SCRATCH,r13 >>>>> mfspr r13,SPRN_SPRG_PACA >>>>> std r10,PACA_EXTLB+EX_TLB_R10(r13) >>>>> mfcr r10 >>>>> std r11,PACA_EXTLB+EX_TLB_R11(r13) >>>>> +#ifdef CONFIG_KVM_BOOKE_HV >>>>> +BEGIN_FTR_SECTION >>>>> + mfspr r11, SPRN_SRR1 >>>>> +END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) >>>>> +#endif >>>> >>>> This thing really should vanish behind DO_KVM :) >>> >>> Then let's do it first for 32-bit ;) >> >> You could #ifdef it in DO_KVM for 64-bit for now. IIRC it's not done on 32-bit because the register value is used even beyond DO_KVM there. > > Nope, 32-bit code is also guarded by CONFIG_KVM_BOOKE_HV. Only in the TLB miss handlers, not the normal exception prolog. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
