| Message ID | 20210922000533.713300-16-seanjc@google.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | perf: KVM: Fix, optimize, and clean up callbacks | expand |
On Wed, 22 Sep 2021 01:05:32 +0100, Sean Christopherson <seanjc@google.com> wrote: > > Call KVM's (un)register perf callbacks helpers directly from arm.c, and > move the PMU bits into pmu.c and rename the related helper accordingly. > > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/arm64/include/asm/kvm_host.h | 3 --- > arch/arm64/kvm/Makefile | 2 +- > arch/arm64/kvm/arm.c | 6 ++++-- > arch/arm64/kvm/perf.c | 27 --------------------------- > arch/arm64/kvm/pmu.c | 8 ++++++++ > include/kvm/arm_pmu.h | 1 + > 6 files changed, 14 insertions(+), 33 deletions(-) > delete mode 100644 arch/arm64/kvm/perf.c > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index 828b6eaa2c56..f141ac65f4f1 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -670,9 +670,6 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len); > int kvm_handle_mmio_return(struct kvm_vcpu *vcpu); > int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa); > > -void kvm_perf_init(void); > -void kvm_perf_teardown(void); > - > #ifdef CONFIG_GUEST_PERF_EVENTS > static inline bool kvm_arch_pmi_in_guest(struct kvm_vcpu *vcpu) > { > diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile > index 989bb5dad2c8..0bcc378b7961 100644 > --- a/arch/arm64/kvm/Makefile > +++ b/arch/arm64/kvm/Makefile > @@ -12,7 +12,7 @@ obj-$(CONFIG_KVM) += hyp/ > > kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ > $(KVM)/vfio.o $(KVM)/irqchip.o $(KVM)/binary_stats.o \ > - arm.o mmu.o mmio.o psci.o perf.o hypercalls.o pvtime.o \ > + arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ > inject_fault.o va_layout.o handle_exit.o \ > guest.o debug.o reset.o sys_regs.o \ > vgic-sys-reg-v3.o fpsimd.o pmu.o \ > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 2b542fdc237e..48f89d80f464 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1744,7 +1744,9 @@ static int init_subsystems(void) > if (err) > goto out; > > - kvm_perf_init(); > + kvm_pmu_init(); > + kvm_register_perf_callbacks(NULL); > + > kvm_sys_reg_table_init(); > > out: > @@ -2160,7 +2162,7 @@ int kvm_arch_init(void *opaque) > /* NOP: Compiling as a module not supported */ > void kvm_arch_exit(void) > { > - kvm_perf_teardown(); > + kvm_unregister_perf_callbacks(); > } > > static int __init early_kvm_mode_cfg(char *arg) > diff --git a/arch/arm64/kvm/perf.c b/arch/arm64/kvm/perf.c > deleted file mode 100644 > index 0b902e0d5b5d..000000000000 > --- a/arch/arm64/kvm/perf.c > +++ /dev/null > @@ -1,27 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0-only > -/* > - * Based on the x86 implementation. > - * > - * Copyright (C) 2012 ARM Ltd. > - * Author: Marc Zyngier <marc.zyngier@arm.com> > - */ > - > -#include <linux/perf_event.h> > -#include <linux/kvm_host.h> > - > -#include <asm/kvm_emulate.h> > - > -DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available); > - > -void kvm_perf_init(void) > -{ > - if (kvm_pmu_probe_pmuver() != 0xf && !is_protected_kvm_enabled()) > - static_branch_enable(&kvm_arm_pmu_available); > - > - kvm_register_perf_callbacks(NULL); > -} > - > -void kvm_perf_teardown(void) > -{ > - kvm_unregister_perf_callbacks(); > -} > diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c > index 03a6c1f4a09a..d98b57a17043 100644 > --- a/arch/arm64/kvm/pmu.c > +++ b/arch/arm64/kvm/pmu.c > @@ -7,6 +7,14 @@ > #include <linux/perf_event.h> > #include <asm/kvm_hyp.h> > > +DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available); > + > +void kvm_pmu_init(void) > +{ > + if (kvm_pmu_probe_pmuver() != 0xf && !is_protected_kvm_enabled()) > + static_branch_enable(&kvm_arm_pmu_available); > +} > + > /* > * Given the perf event attributes and system type, determine > * if we are going to need to switch counters at guest entry/exit. > diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h > index 864b9997efb2..42270676498d 100644 > --- a/include/kvm/arm_pmu.h > +++ b/include/kvm/arm_pmu.h > @@ -14,6 +14,7 @@ > #define ARMV8_PMU_MAX_COUNTER_PAIRS ((ARMV8_PMU_MAX_COUNTERS + 1) >> 1) > > DECLARE_STATIC_KEY_FALSE(kvm_arm_pmu_available); > +void kvm_pmu_init(void); > > static __always_inline bool kvm_arm_support_pmu_v3(void) > { Note that this patch is now conflicting with e840f42a4992 ("KVM: arm64: Fix PMU probe ordering"), which was merged in -rc4. Moving the static key definition to arch/arm64/kvm/pmu-emul.c and getting rid of kvm_pmu_init() altogether should be enough to resolve it. With that, Reviewed-by: Marc Zyngier <maz@kernel.org> M.
On Mon, Oct 11, 2021, Marc Zyngier wrote: > On Wed, 22 Sep 2021 01:05:32 +0100, > Sean Christopherson <seanjc@google.com> wrote: > > diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h > > index 864b9997efb2..42270676498d 100644 > > --- a/include/kvm/arm_pmu.h > > +++ b/include/kvm/arm_pmu.h > > @@ -14,6 +14,7 @@ > > #define ARMV8_PMU_MAX_COUNTER_PAIRS ((ARMV8_PMU_MAX_COUNTERS + 1) >> 1) > > > > DECLARE_STATIC_KEY_FALSE(kvm_arm_pmu_available); > > +void kvm_pmu_init(void); > > > > static __always_inline bool kvm_arm_support_pmu_v3(void) > > { > > Note that this patch is now conflicting with e840f42a4992 ("KVM: > arm64: Fix PMU probe ordering"), which was merged in -rc4. Moving the > static key definition to arch/arm64/kvm/pmu-emul.c and getting rid of > kvm_pmu_init() altogether should be enough to resolve it. Defining kvm_arm_pmu_available in pmu-emul.c doesn't work as-is because pmu-emul.c depends on CONFIG_HW_PERF_EVENTS=y. Since pmu-emul.c is the only path that enables the key, my plan is to add a prep match to bury kvm_arm_pmu_available behind the existing #ifdef CONFIG_HW_PERF_EVENTS in arm_pmu.h and add a stub for kvm_arm_support_pmu_v3(). The only ugly part is that the KVM_NVHE_ALIAS() also gains an #ifdef, but that doesn't seem too bad.
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 828b6eaa2c56..f141ac65f4f1 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -670,9 +670,6 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len); int kvm_handle_mmio_return(struct kvm_vcpu *vcpu); int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa); -void kvm_perf_init(void); -void kvm_perf_teardown(void); - #ifdef CONFIG_GUEST_PERF_EVENTS static inline bool kvm_arch_pmi_in_guest(struct kvm_vcpu *vcpu) { diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 989bb5dad2c8..0bcc378b7961 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -12,7 +12,7 @@ obj-$(CONFIG_KVM) += hyp/ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ $(KVM)/vfio.o $(KVM)/irqchip.o $(KVM)/binary_stats.o \ - arm.o mmu.o mmio.o psci.o perf.o hypercalls.o pvtime.o \ + arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 2b542fdc237e..48f89d80f464 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1744,7 +1744,9 @@ static int init_subsystems(void) if (err) goto out; - kvm_perf_init(); + kvm_pmu_init(); + kvm_register_perf_callbacks(NULL); + kvm_sys_reg_table_init(); out: @@ -2160,7 +2162,7 @@ int kvm_arch_init(void *opaque) /* NOP: Compiling as a module not supported */ void kvm_arch_exit(void) { - kvm_perf_teardown(); + kvm_unregister_perf_callbacks(); } static int __init early_kvm_mode_cfg(char *arg) diff --git a/arch/arm64/kvm/perf.c b/arch/arm64/kvm/perf.c deleted file mode 100644 index 0b902e0d5b5d..000000000000 --- a/arch/arm64/kvm/perf.c +++ /dev/null @@ -1,27 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Based on the x86 implementation. - * - * Copyright (C) 2012 ARM Ltd. - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/perf_event.h> -#include <linux/kvm_host.h> - -#include <asm/kvm_emulate.h> - -DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available); - -void kvm_perf_init(void) -{ - if (kvm_pmu_probe_pmuver() != 0xf && !is_protected_kvm_enabled()) - static_branch_enable(&kvm_arm_pmu_available); - - kvm_register_perf_callbacks(NULL); -} - -void kvm_perf_teardown(void) -{ - kvm_unregister_perf_callbacks(); -} diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index 03a6c1f4a09a..d98b57a17043 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -7,6 +7,14 @@ #include <linux/perf_event.h> #include <asm/kvm_hyp.h> +DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available); + +void kvm_pmu_init(void) +{ + if (kvm_pmu_probe_pmuver() != 0xf && !is_protected_kvm_enabled()) + static_branch_enable(&kvm_arm_pmu_available); +} + /* * Given the perf event attributes and system type, determine * if we are going to need to switch counters at guest entry/exit. diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 864b9997efb2..42270676498d 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -14,6 +14,7 @@ #define ARMV8_PMU_MAX_COUNTER_PAIRS ((ARMV8_PMU_MAX_COUNTERS + 1) >> 1) DECLARE_STATIC_KEY_FALSE(kvm_arm_pmu_available); +void kvm_pmu_init(void); static __always_inline bool kvm_arm_support_pmu_v3(void) {
Call KVM's (un)register perf callbacks helpers directly from arm.c, and move the PMU bits into pmu.c and rename the related helper accordingly. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/arm64/include/asm/kvm_host.h | 3 --- arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/arm.c | 6 ++++-- arch/arm64/kvm/perf.c | 27 --------------------------- arch/arm64/kvm/pmu.c | 8 ++++++++ include/kvm/arm_pmu.h | 1 + 6 files changed, 14 insertions(+), 33 deletions(-) delete mode 100644 arch/arm64/kvm/perf.c