[PATCH v2 24/37] KVM: PPC: Book3S HV P9: inline kvmhv_load_hv_regs_and_go into __kvmhv_vcpu_entry_p9

Fabiano Rosas farosas at linux.ibm.com
Wed Mar 3 00:48:35 AEDT 2021


Nicholas Piggin <npiggin at gmail.com> writes:

> Now the initial C implementation is done, inline more HV code to make
> rearranging things easier.
>
> And rename __kvmhv_vcpu_entry_p9 to drop the leading underscores as it's
> now C, and is now a more complete vcpu entry.
>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>

Reviewed-by: Fabiano Rosas <farosas at linux.ibm.com>

> ---
>  arch/powerpc/include/asm/kvm_book3s_64.h |   2 +-
>  arch/powerpc/kvm/book3s_hv.c             | 181 +----------------------
>  arch/powerpc/kvm/book3s_hv_interrupt.c   | 168 ++++++++++++++++++++-
>  3 files changed, 169 insertions(+), 182 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
> index c214bcffb441..eaf3a562bf1e 100644
> --- a/arch/powerpc/include/asm/kvm_book3s_64.h
> +++ b/arch/powerpc/include/asm/kvm_book3s_64.h
> @@ -153,7 +153,7 @@ static inline bool kvmhv_vcpu_is_radix(struct kvm_vcpu *vcpu)
>  	return radix;
>  }
>
> -int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu);
> +int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr);
>
>  #define KVM_DEFAULT_HPT_ORDER	24	/* 16MB HPT by default */
>  #endif
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 28a2761515e3..f99503acdda5 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -3442,183 +3442,6 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
>  	trace_kvmppc_run_core(vc, 1);
>  }
>
> -static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
> -{
> -	struct kvmppc_vcore *vc = vcpu->arch.vcore;
> -	struct kvm_nested_guest *nested = vcpu->arch.nested;
> -	u32 lpid;
> -
> -	lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
> -
> -	mtspr(SPRN_LPID, lpid);
> -	mtspr(SPRN_LPCR, lpcr);
> -	mtspr(SPRN_PID, vcpu->arch.pid);
> -	isync();
> -
> -	/* TLBIEL must have LPIDR set, so set guest LPID before flushing. */
> -	kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
> -}
> -
> -static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
> -{
> -	mtspr(SPRN_PID, pid);
> -	mtspr(SPRN_LPID, kvm->arch.host_lpid);
> -	mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
> -	isync();
> -}
> -
> -/*
> - * Load up hypervisor-mode registers on P9.
> - */
> -static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
> -				     unsigned long lpcr)
> -{
> -	struct kvm *kvm = vcpu->kvm;
> -	struct kvmppc_vcore *vc = vcpu->arch.vcore;
> -	s64 hdec;
> -	u64 tb, purr, spurr;
> -	int trap;
> -	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
> -	unsigned long host_ciabr = mfspr(SPRN_CIABR);
> -	unsigned long host_dawr0 = mfspr(SPRN_DAWR0);
> -	unsigned long host_dawrx0 = mfspr(SPRN_DAWRX0);
> -	unsigned long host_psscr = mfspr(SPRN_PSSCR);
> -	unsigned long host_pidr = mfspr(SPRN_PID);
> -	unsigned long host_dawr1 = 0;
> -	unsigned long host_dawrx1 = 0;
> -
> -	if (cpu_has_feature(CPU_FTR_DAWR1)) {
> -		host_dawr1 = mfspr(SPRN_DAWR1);
> -		host_dawrx1 = mfspr(SPRN_DAWRX1);
> -	}
> -
> -	tb = mftb();
> -	hdec = time_limit - tb;
> -	if (hdec < 0)
> -		return BOOK3S_INTERRUPT_HV_DECREMENTER;
> -
> -	if (vc->tb_offset) {
> -		u64 new_tb = tb + vc->tb_offset;
> -		mtspr(SPRN_TBU40, new_tb);
> -		tb = mftb();
> -		if ((tb & 0xffffff) < (new_tb & 0xffffff))
> -			mtspr(SPRN_TBU40, new_tb + 0x1000000);
> -		vc->tb_offset_applied = vc->tb_offset;
> -	}
> -
> -	if (vc->pcr)
> -		mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
> -	mtspr(SPRN_DPDES, vc->dpdes);
> -	mtspr(SPRN_VTB, vc->vtb);
> -
> -	local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
> -	local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
> -	mtspr(SPRN_PURR, vcpu->arch.purr);
> -	mtspr(SPRN_SPURR, vcpu->arch.spurr);
> -
> -	if (dawr_enabled()) {
> -		mtspr(SPRN_DAWR0, vcpu->arch.dawr0);
> -		mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0);
> -		if (cpu_has_feature(CPU_FTR_DAWR1)) {
> -			mtspr(SPRN_DAWR1, vcpu->arch.dawr1);
> -			mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1);
> -		}
> -	}
> -	mtspr(SPRN_CIABR, vcpu->arch.ciabr);
> -	mtspr(SPRN_IC, vcpu->arch.ic);
> -
> -	mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
> -	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
> -
> -	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
> -
> -	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
> -	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
> -	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
> -	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
> -
> -	mtspr(SPRN_AMOR, ~0UL);
> -
> -	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
> -
> -	/*
> -	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
> -	 * so set guest LPCR (with HDICE) before writing HDEC.
> -	 */
> -	mtspr(SPRN_HDEC, hdec);
> -
> -	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
> -	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
> -
> -	trap = __kvmhv_vcpu_entry_p9(vcpu);
> -
> -	/* Advance host PURR/SPURR by the amount used by guest */
> -	purr = mfspr(SPRN_PURR);
> -	spurr = mfspr(SPRN_SPURR);
> -	mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr +
> -	      purr - vcpu->arch.purr);
> -	mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr +
> -	      spurr - vcpu->arch.spurr);
> -	vcpu->arch.purr = purr;
> -	vcpu->arch.spurr = spurr;
> -
> -	vcpu->arch.ic = mfspr(SPRN_IC);
> -	vcpu->arch.pid = mfspr(SPRN_PID);
> -	vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
> -
> -	vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
> -	vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
> -	vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
> -	vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
> -
> -	/* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
> -	mtspr(SPRN_PSSCR, host_psscr |
> -	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
> -	mtspr(SPRN_HFSCR, host_hfscr);
> -	mtspr(SPRN_CIABR, host_ciabr);
> -	mtspr(SPRN_DAWR0, host_dawr0);
> -	mtspr(SPRN_DAWRX0, host_dawrx0);
> -	if (cpu_has_feature(CPU_FTR_DAWR1)) {
> -		mtspr(SPRN_DAWR1, host_dawr1);
> -		mtspr(SPRN_DAWRX1, host_dawrx1);
> -	}
> -
> -	/*
> -	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
> -	 * case we interrupted the guest between a tlbie and a ptesync.
> -	 */
> -	asm volatile("eieio; tlbsync; ptesync");
> -
> -	/*
> -	 * cp_abort is required if the processor supports local copy-paste
> -	 * to clear the copy buffer that was under control of the guest.
> -	 */
> -	if (cpu_has_feature(CPU_FTR_ARCH_31))
> -		asm volatile(PPC_CP_ABORT);
> -
> -	vc->dpdes = mfspr(SPRN_DPDES);
> -	vc->vtb = mfspr(SPRN_VTB);
> -	mtspr(SPRN_DPDES, 0);
> -	if (vc->pcr)
> -		mtspr(SPRN_PCR, PCR_MASK);
> -
> -	if (vc->tb_offset_applied) {
> -		u64 new_tb = mftb() - vc->tb_offset_applied;
> -		mtspr(SPRN_TBU40, new_tb);
> -		tb = mftb();
> -		if ((tb & 0xffffff) < (new_tb & 0xffffff))
> -			mtspr(SPRN_TBU40, new_tb + 0x1000000);
> -		vc->tb_offset_applied = 0;
> -	}
> -
> -	/* HDEC must be at least as large as DEC, so decrementer_max fits */
> -	mtspr(SPRN_HDEC, decrementer_max);
> -
> -	switch_mmu_to_host_radix(kvm, host_pidr);
> -
> -	return trap;
> -}
> -
>  /*
>   * Virtual-mode guest entry for POWER9 and later when the host and
>   * guest are both using the radix MMU.  The LPIDR has already been set.
> @@ -3710,7 +3533,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>  		 * We need to save and restore the guest visible part of the
>  		 * psscr (i.e. using SPRN_PSSCR_PR) since the hypervisor
>  		 * doesn't do this for us. Note only required if pseries since
> -		 * this is done in kvmhv_load_hv_regs_and_go() below otherwise.
> +		 * this is done in kvmhv_vcpu_entry_p9() below otherwise.
>  		 */
>  		unsigned long host_psscr;
>  		/* call our hypervisor to load up HV regs and go */
> @@ -3748,7 +3571,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>
>  	} else {
>  		kvmppc_xive_push_vcpu(vcpu);
> -		trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
> +		trap = kvmhv_vcpu_entry_p9(vcpu, time_limit, lpcr);
>  		/* H_CEDE has to be handled now, not later */
>  		/* XICS hcalls must be handled before xive is pulled */
>  		if (trap == BOOK3S_INTERRUPT_SYSCALL &&
> diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
> index 5a7b036c447f..dea3eca3648a 100644
> --- a/arch/powerpc/kvm/book3s_hv_interrupt.c
> +++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
> @@ -55,6 +55,31 @@ static void __accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator
>  #define accumulate_time(vcpu, next) do {} while (0)
>  #endif
>
> +static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
> +{
> +	struct kvmppc_vcore *vc = vcpu->arch.vcore;
> +	struct kvm_nested_guest *nested = vcpu->arch.nested;
> +	u32 lpid;
> +
> +	lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
> +
> +	mtspr(SPRN_LPID, lpid);
> +	mtspr(SPRN_LPCR, lpcr);
> +	mtspr(SPRN_PID, vcpu->arch.pid);
> +	isync();
> +
> +	/* TLBIEL must have LPIDR set, so set guest LPID before flushing. */
> +	kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
> +}
> +
> +static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
> +{
> +	mtspr(SPRN_PID, pid);
> +	mtspr(SPRN_LPID, kvm->arch.host_lpid);
> +	mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
> +	isync();
> +}
> +
>  static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
>  {
>  	asm volatile("slbmfev  %0,%1" : "=r" (*slbev) : "r" (idx));
> @@ -94,11 +119,86 @@ static void radix_clear_slb(void)
>  	}
>  }
>
> -int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu)
> +int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr)
>  {
> +	struct kvm *kvm = vcpu->kvm;
> +	struct kvmppc_vcore *vc = vcpu->arch.vcore;
> +	s64 hdec;
> +	u64 tb, purr, spurr;
>  	u64 *exsave;
>  	unsigned long msr = mfmsr();
>  	int trap;
> +	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
> +	unsigned long host_ciabr = mfspr(SPRN_CIABR);
> +	unsigned long host_dawr0 = mfspr(SPRN_DAWR0);
> +	unsigned long host_dawrx0 = mfspr(SPRN_DAWRX0);
> +	unsigned long host_psscr = mfspr(SPRN_PSSCR);
> +	unsigned long host_pidr = mfspr(SPRN_PID);
> +	unsigned long host_dawr1 = 0;
> +	unsigned long host_dawrx1 = 0;
> +
> +	if (cpu_has_feature(CPU_FTR_DAWR1)) {
> +		host_dawr1 = mfspr(SPRN_DAWR1);
> +		host_dawrx1 = mfspr(SPRN_DAWRX1);
> +	}
> +
> +	tb = mftb();
> +	hdec = time_limit - tb;
> +	if (hdec < 0)
> +		return BOOK3S_INTERRUPT_HV_DECREMENTER;
> +
> +	if (vc->tb_offset) {
> +		u64 new_tb = tb + vc->tb_offset;
> +		mtspr(SPRN_TBU40, new_tb);
> +		tb = mftb();
> +		if ((tb & 0xffffff) < (new_tb & 0xffffff))
> +			mtspr(SPRN_TBU40, new_tb + 0x1000000);
> +		vc->tb_offset_applied = vc->tb_offset;
> +	}
> +
> +	if (vc->pcr)
> +		mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
> +	mtspr(SPRN_DPDES, vc->dpdes);
> +	mtspr(SPRN_VTB, vc->vtb);
> +
> +	local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
> +	local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
> +	mtspr(SPRN_PURR, vcpu->arch.purr);
> +	mtspr(SPRN_SPURR, vcpu->arch.spurr);
> +
> +	if (dawr_enabled()) {
> +		mtspr(SPRN_DAWR0, vcpu->arch.dawr0);
> +		mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0);
> +		if (cpu_has_feature(CPU_FTR_DAWR1)) {
> +			mtspr(SPRN_DAWR1, vcpu->arch.dawr1);
> +			mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1);
> +		}
> +	}
> +	mtspr(SPRN_CIABR, vcpu->arch.ciabr);
> +	mtspr(SPRN_IC, vcpu->arch.ic);
> +
> +	mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
> +	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
> +
> +	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
> +
> +	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
> +	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
> +	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
> +	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
> +
> +	mtspr(SPRN_AMOR, ~0UL);
> +
> +	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
> +
> +	/*
> +	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
> +	 * so set guest LPCR (with HDICE) before writing HDEC.
> +	 */
> +	mtspr(SPRN_HDEC, hdec);
> +
> +	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
> +	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
>
>  	start_timing(vcpu, &vcpu->arch.rm_entry);
>
> @@ -216,6 +316,70 @@ int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu)
>
>  	end_timing(vcpu);
>
> +	/* Advance host PURR/SPURR by the amount used by guest */
> +	purr = mfspr(SPRN_PURR);
> +	spurr = mfspr(SPRN_SPURR);
> +	mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr +
> +	      purr - vcpu->arch.purr);
> +	mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr +
> +	      spurr - vcpu->arch.spurr);
> +	vcpu->arch.purr = purr;
> +	vcpu->arch.spurr = spurr;
> +
> +	vcpu->arch.ic = mfspr(SPRN_IC);
> +	vcpu->arch.pid = mfspr(SPRN_PID);
> +	vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
> +
> +	vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
> +	vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
> +	vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
> +	vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
> +
> +	/* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
> +	mtspr(SPRN_PSSCR, host_psscr |
> +	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
> +	mtspr(SPRN_HFSCR, host_hfscr);
> +	mtspr(SPRN_CIABR, host_ciabr);
> +	mtspr(SPRN_DAWR0, host_dawr0);
> +	mtspr(SPRN_DAWRX0, host_dawrx0);
> +	if (cpu_has_feature(CPU_FTR_DAWR1)) {
> +		mtspr(SPRN_DAWR1, host_dawr1);
> +		mtspr(SPRN_DAWRX1, host_dawrx1);
> +	}
> +
> +	/*
> +	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
> +	 * case we interrupted the guest between a tlbie and a ptesync.
> +	 */
> +	asm volatile("eieio; tlbsync; ptesync");
> +
> +	/*
> +	 * cp_abort is required if the processor supports local copy-paste
> +	 * to clear the copy buffer that was under control of the guest.
> +	 */
> +	if (cpu_has_feature(CPU_FTR_ARCH_31))
> +		asm volatile(PPC_CP_ABORT);
> +
> +	vc->dpdes = mfspr(SPRN_DPDES);
> +	vc->vtb = mfspr(SPRN_VTB);
> +	mtspr(SPRN_DPDES, 0);
> +	if (vc->pcr)
> +		mtspr(SPRN_PCR, PCR_MASK);
> +
> +	if (vc->tb_offset_applied) {
> +		u64 new_tb = mftb() - vc->tb_offset_applied;
> +		mtspr(SPRN_TBU40, new_tb);
> +		tb = mftb();
> +		if ((tb & 0xffffff) < (new_tb & 0xffffff))
> +			mtspr(SPRN_TBU40, new_tb + 0x1000000);
> +		vc->tb_offset_applied = 0;
> +	}
> +
> +	/* HDEC must be at least as large as DEC, so decrementer_max fits */
> +	mtspr(SPRN_HDEC, decrementer_max);
> +
> +	switch_mmu_to_host_radix(kvm, host_pidr);
> +
>  	return trap;
>  }
> -EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9);
> +EXPORT_SYMBOL_GPL(kvmhv_vcpu_entry_p9);


More information about the Linuxppc-dev mailing list