From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicholas Piggin Date: Tue, 22 Jun 2021 10:57:14 +0000 Subject: [RFC PATCH 21/43] KVM: PPC: Book3S HV P9: Move TB updates Message-Id: <20210622105736.633352-22-npiggin@gmail.com> List-Id: References: <20210622105736.633352-1-npiggin@gmail.com> In-Reply-To: <20210622105736.633352-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ppc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin Move the TB updates between saving and loading guest and host SPRs, to improve scheduling by keeping issue-NTC operations together as much as possible. Signed-off-by: Nicholas Piggin --- arch/powerpc/kvm/book3s_hv_p9_entry.c | 36 +++++++++++++-------------- 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_p9_entry.c b/arch/powerpc/kvm/book3s_hv_p9_entry.c index 469dd5cbb52d..44ee805875ba 100644 --- a/arch/powerpc/kvm/book3s_hv_p9_entry.c +++ b/arch/powerpc/kvm/book3s_hv_p9_entry.c @@ -215,15 +215,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc vcpu->arch.ceded = 0; - 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; - } - /* Could avoid mfmsr by passing around, but probably no big deal */ msr = mfmsr(); @@ -238,6 +229,15 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc host_dawrx1 = mfspr(SPRN_DAWRX1); } + 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); @@ -454,6 +454,15 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc tb = mftb(); vcpu->arch.dec_expires = dec + tb; + if (vc->tb_offset_applied) { + u64 new_tb = tb - 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; + } + /* 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)); @@ -488,15 +497,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc 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); -- 2.23.0