From 2ce008c8b25467ceacf45bcf0e183d660edb82f2 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 28 May 2021 19:07:45 +1000 Subject: [PATCH] KVM: PPC: Book3S HV: Remove unused nested HV tests in XICS emulation Commit f3c18e9342a44 ("KVM: PPC: Book3S HV: Use XICS hypercalls when running as a nested hypervisor") added nested HV tests in XICS hypercalls, but not all are required. * icp_eoi is only called by kvmppc_deliver_irq_passthru which is only called by kvmppc_check_passthru which is only caled by kvmppc_read_one_intr. * kvmppc_read_one_intr is only called by kvmppc_read_intr which is only called by the L0 HV rmhandlers code. * kvmhv_rm_send_ipi is called by: - kvmhv_interrupt_vcore which is only called by kvmhv_commence_exit which is only called by the L0 HV rmhandlers code. - icp_send_hcore_msg which is only called by icp_rm_set_vcpu_irq. - icp_rm_set_vcpu_irq which is only called by icp_rm_try_update - icp_rm_set_vcpu_irq is not nested HV safe because it writes to LPCR directly without a kvmhv_on_pseries test. Nested handlers should not in general be using the rm handlers. The important test seems to be in kvmppc_ipi_thread, which sends the virt-mode H_IPI handler kick to use smp_call_function rather than msgsnd. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210528090752.3542186-26-npiggin@gmail.com --- arch/powerpc/kvm/book3s_hv_builtin.c | 44 +++++++----------------------------- arch/powerpc/kvm/book3s_hv_rm_xics.c | 15 ------------ 2 files changed, 8 insertions(+), 51 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index 8d669a0..259492b 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -199,15 +199,6 @@ void kvmhv_rm_send_ipi(int cpu) void __iomem *xics_phys; unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER); - /* For a nested hypervisor, use the XICS via hcall */ - if (kvmhv_on_pseries()) { - unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; - - plpar_hcall_raw(H_IPI, retbuf, get_hard_smp_processor_id(cpu), - IPI_PRIORITY); - return; - } - /* On POWER9 we can use msgsnd for any destination cpu. */ if (cpu_has_feature(CPU_FTR_ARCH_300)) { msg |= get_hard_smp_processor_id(cpu); @@ -420,19 +411,12 @@ static long kvmppc_read_one_intr(bool *again) return 1; /* Now read the interrupt from the ICP */ - if (kvmhv_on_pseries()) { - unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; - - rc = plpar_hcall_raw(H_XIRR, retbuf, 0xFF); - xirr = cpu_to_be32(retbuf[0]); - } else { - xics_phys = local_paca->kvm_hstate.xics_phys; - rc = 0; - if (!xics_phys) - rc = opal_int_get_xirr(&xirr, false); - else - xirr = __raw_rm_readl(xics_phys + XICS_XIRR); - } + xics_phys = local_paca->kvm_hstate.xics_phys; + rc = 0; + if (!xics_phys) + rc = opal_int_get_xirr(&xirr, false); + else + xirr = __raw_rm_readl(xics_phys + XICS_XIRR); if (rc < 0) return 1; @@ -461,13 +445,7 @@ static long kvmppc_read_one_intr(bool *again) */ if (xisr == XICS_IPI) { rc = 0; - if (kvmhv_on_pseries()) { - unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; - - plpar_hcall_raw(H_IPI, retbuf, - hard_smp_processor_id(), 0xff); - plpar_hcall_raw(H_EOI, retbuf, h_xirr); - } else if (xics_phys) { + if (xics_phys) { __raw_rm_writeb(0xff, xics_phys + XICS_MFRR); __raw_rm_writel(xirr, xics_phys + XICS_XIRR); } else { @@ -493,13 +471,7 @@ static long kvmppc_read_one_intr(bool *again) /* We raced with the host, * we need to resend that IPI, bummer */ - if (kvmhv_on_pseries()) { - unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; - - plpar_hcall_raw(H_IPI, retbuf, - hard_smp_processor_id(), - IPI_PRIORITY); - } else if (xics_phys) + if (xics_phys) __raw_rm_writeb(IPI_PRIORITY, xics_phys + XICS_MFRR); else diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c index c2c9c73..0a11ec8 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_xics.c +++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c @@ -141,13 +141,6 @@ static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu, return; } - if (xive_enabled() && kvmhv_on_pseries()) { - /* No XICS access or hypercalls available, too hard */ - this_icp->rm_action |= XICS_RM_KICK_VCPU; - this_icp->rm_kick_target = vcpu; - return; - } - /* * Check if the core is loaded, * if not, find an available host core to post to wake the VCPU, @@ -771,14 +764,6 @@ static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again) void __iomem *xics_phys; int64_t rc; - if (kvmhv_on_pseries()) { - unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; - - iosync(); - plpar_hcall_raw(H_EOI, retbuf, hwirq); - return; - } - rc = pnv_opal_pci_msi_eoi(c, hwirq); if (rc) -- 2.7.4