From: Nicholas Piggin <npiggin@gmail.com>
To: kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>
Subject: [PATCH v3 41/52] KVM: PPC: Book3S HV P9: Don't restore PSSCR if not needed
Date: Tue, 5 Oct 2021 02:00:38 +1000 [thread overview]
Message-ID: <20211004160049.1338837-42-npiggin@gmail.com> (raw)
In-Reply-To: <20211004160049.1338837-1-npiggin@gmail.com>
This also moves the PSSCR update in nested entry to avoid a SPR
scoreboard stall.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kvm/book3s_hv.c | 7 +++++--
arch/powerpc/kvm/book3s_hv_p9_entry.c | 26 +++++++++++++++++++-------
2 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index f4445cc5a29a..f10cb4167549 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3876,7 +3876,9 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns
if (unlikely(load_vcpu_state(vcpu, &host_os_sprs)))
msr = mfmsr(); /* TM restore can update msr */
- mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr);
+ if (vcpu->arch.psscr != host_psscr)
+ mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr);
+
kvmhv_save_hv_regs(vcpu, &hvregs);
hvregs.lpcr = lpcr;
vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
@@ -3917,7 +3919,6 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns
vcpu->arch.shregs.dar = mfspr(SPRN_DAR);
vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR);
vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR);
- mtspr(SPRN_PSSCR_PR, host_psscr);
store_vcpu_state(vcpu);
@@ -3930,6 +3931,8 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns
timer_rearm_host_dec(*tb);
restore_p9_host_os_sprs(vcpu, &host_os_sprs);
+ if (vcpu->arch.psscr != host_psscr)
+ mtspr(SPRN_PSSCR_PR, host_psscr);
return trap;
}
diff --git a/arch/powerpc/kvm/book3s_hv_p9_entry.c b/arch/powerpc/kvm/book3s_hv_p9_entry.c
index 0f341011816c..eae9d806d704 100644
--- a/arch/powerpc/kvm/book3s_hv_p9_entry.c
+++ b/arch/powerpc/kvm/book3s_hv_p9_entry.c
@@ -649,6 +649,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
unsigned long host_dawr0;
unsigned long host_dawrx0;
unsigned long host_psscr;
+ unsigned long host_hpsscr;
unsigned long host_pidr;
unsigned long host_dawr1;
unsigned long host_dawrx1;
@@ -666,7 +667,9 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
host_hfscr = mfspr(SPRN_HFSCR);
host_ciabr = mfspr(SPRN_CIABR);
- host_psscr = mfspr(SPRN_PSSCR);
+ host_psscr = mfspr(SPRN_PSSCR_PR);
+ if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST))
+ host_hpsscr = mfspr(SPRN_PSSCR);
host_pidr = mfspr(SPRN_PID);
if (dawr_enabled()) {
@@ -750,8 +753,14 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
if (vcpu->arch.ciabr != host_ciabr)
mtspr(SPRN_CIABR, vcpu->arch.ciabr);
- mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
- (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+
+ if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
+ mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
+ (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+ } else {
+ if (vcpu->arch.psscr != host_psscr)
+ mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr);
+ }
mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
@@ -957,7 +966,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
vcpu->arch.ic = mfspr(SPRN_IC);
vcpu->arch.pid = mfspr(SPRN_PID);
- vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
+ vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR);
vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
@@ -1003,9 +1012,12 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr);
mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr);
- /* 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));
+ if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) {
+ /* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
+ mtspr(SPRN_PSSCR, host_hpsscr |
+ (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+ }
+
mtspr(SPRN_HFSCR, host_hfscr);
if (vcpu->arch.ciabr != host_ciabr)
mtspr(SPRN_CIABR, host_ciabr);
--
2.23.0
next prev parent reply other threads:[~2021-10-04 16:28 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-04 15:59 [PATCH v3 00/52] KVM: PPC: Book3S HV P9: entry/exit optimisations Nicholas Piggin
2021-10-04 15:59 ` [PATCH v3 01/52] powerpc/64s: Remove WORT SPR from POWER9/10 (take 2) Nicholas Piggin
2021-10-04 15:59 ` [PATCH v3 02/52] powerpc/64s: guard optional TIDR SPR with CPU ftr test Nicholas Piggin
2021-10-11 18:44 ` Fabiano Rosas
2021-10-12 2:08 ` Michael Ellerman
2021-10-13 16:51 ` Fabiano Rosas
2021-10-04 16:00 ` [PATCH v3 03/52] KMV: PPC: Book3S HV P9: Use set_dec to set decrementer to host Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 04/52] KVM: PPC: Book3S HV P9: Use host timer accounting to avoid decrementer read Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 05/52] KVM: PPC: Book3S HV P9: Use large decrementer for HDEC Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 06/52] KVM: PPC: Book3S HV P9: Reduce mftb per guest entry/exit Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 07/52] powerpc/time: add API for KVM to re-arm the host timer/decrementer Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 08/52] KVM: PPC: Book3S HV: POWER10 enable HAIL when running radix guests Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 09/52] powerpc/64s: Keep AMOR SPR a constant ~0 at runtime Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 10/52] KVM: PPC: Book3S HV: Don't always save PMU for guest capable of nesting Nicholas Piggin
2021-10-16 12:38 ` Fabiano Rosas
2021-10-20 5:26 ` Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 11/52] powerpc/64s: Always set PMU control registers to frozen/disabled when not in use Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 12/52] powerpc/64s: Implement PMU override command line option Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 13/52] KVM: PPC: Book3S HV P9: Implement PMU save/restore in C Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 14/52] KVM: PPC: Book3S HV P9: Factor PMU save/load into context switch functions Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 15/52] KVM: PPC: Book3S HV P9: Demand fault PMU SPRs when marked not inuse Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 16/52] KVM: PPC: Book3S HV P9: Factor out yield_count increment Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 17/52] KVM: PPC: Book3S HV: CTRL SPR does not require read-modify-write Nicholas Piggin
2021-10-16 12:54 ` Fabiano Rosas
2021-10-04 16:00 ` [PATCH v3 18/52] KVM: PPC: Book3S HV P9: Move SPRG restore to restore_p9_host_os_sprs Nicholas Piggin
2021-10-16 12:59 ` Fabiano Rosas
2021-10-04 16:00 ` [PATCH v3 19/52] KVM: PPC: Book3S HV P9: Reduce mtmsrd instructions required to save host SPRs Nicholas Piggin
2021-10-16 13:45 ` Fabiano Rosas
2021-10-20 5:35 ` Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 20/52] KVM: PPC: Book3S HV P9: Improve mtmsrd scheduling by delaying MSR[EE] disable Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 21/52] KVM: PPC: Book3S HV P9: Add kvmppc_stop_thread to match kvmppc_start_thread Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 22/52] KVM: PPC: Book3S HV: Change dec_expires to be relative to guest timebase Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 23/52] KVM: PPC: Book3S HV P9: Move TB updates Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 24/52] KVM: PPC: Book3S HV P9: Optimise timebase reads Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 25/52] KVM: PPC: Book3S HV P9: Avoid SPR scoreboard stalls Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 26/52] KVM: PPC: Book3S HV P9: Only execute mtSPR if the value changed Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 27/52] KVM: PPC: Book3S HV P9: Juggle SPR switching around Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 28/52] KVM: PPC: Book3S HV P9: Move vcpu register save/restore into functions Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 29/52] KVM: PPC: Book3S HV P9: Move host OS save/restore functions to built-in Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 30/52] KVM: PPC: Book3S HV P9: Move nested guest entry into its own function Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 31/52] KVM: PPC: Book3S HV P9: Move remaining SPR and MSR access into low level entry Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 32/52] KVM: PPC: Book3S HV P9: Implement TM fastpath for guest entry/exit Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 33/52] KVM: PPC: Book3S HV P9: Switch PMU to guest as late as possible Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 34/52] KVM: PPC: Book3S HV P9: Restrict DSISR canary workaround to processors that require it Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 35/52] KVM: PPC: Book3S HV P9: More SPR speed improvements Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 36/52] KVM: PPC: Book3S HV P9: Demand fault EBB facility registers Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 37/52] KVM: PPC: Book3S HV P9: Demand fault TM " Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 38/52] KVM: PPC: Book3S HV P9: Use Linux SPR save/restore to manage some host SPRs Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 39/52] KVM: PPC: Book3S HV P9: Comment and fix MMU context switching code Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 40/52] KVM: PPC: Book3S HV P9: Test dawr_enabled() before saving host DAWR SPRs Nicholas Piggin
2021-10-04 16:00 ` Nicholas Piggin [this message]
2021-10-04 16:00 ` [PATCH v3 42/52] KVM: PPC: Book3S HV P9: Avoid tlbsync sequence on radix guest exit Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 43/52] KVM: PPC: Book3S HV Nested: Avoid extra mftb() in nested entry Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 44/52] KVM: PPC: Book3S HV P9: Improve mfmsr performance on entry Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 45/52] KVM: PPC: Book3S HV P9: Optimise hash guest SLB saving Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 46/52] KVM: PPC: Book3S HV P9: Avoid changing MSR[RI] in entry and exit Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 47/52] KVM: PPC: Book3S HV P9: Add unlikely annotation for !mmu_ready Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 48/52] KVM: PPC: Book3S HV P9: Avoid cpu_in_guest atomics on entry and exit Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 49/52] KVM: PPC: Book3S HV P9: Remove most of the vcore logic Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 50/52] KVM: PPC: Book3S HV P9: Tidy kvmppc_create_dtl_entry Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 51/52] KVM: PPC: Book3S HV P9: Stop using vc->dpdes Nicholas Piggin
2021-10-04 16:00 ` [PATCH v3 52/52] KVM: PPC: Book3S HV P9: Remove subcore HMI handling Nicholas Piggin
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