[1/2] perf: arm_pmuv3: Remove cyclical dependency with kvm_host.h

Commit Message

Colton Lewis Feb. 4, 2025, 7:57 p.m. UTC

asm/kvm_host.h includes asm/arm_pmu.h which includes perf/arm_pmuv3.h
which includes asm/arm_pmuv3.h which includes asm/kvm_host.h This
causes confusing compilation problems when trying to use anything in
the chain.

Break the cycle by taking asm/kvm_host.h out of asm/arm_pmuv3.h
because asm/kvm_host.h is huge and we only need a few functions from
it. Move the required declarations to asm/arm_pmuv3.h.

Signed-off-by: Colton Lewis <[e-mail]>
---
 arch/arm64/include/asm/arm_pmuv3.h | 24 ++++++++++++++++++++++--
 arch/arm64/include/asm/kvm_host.h  | 18 ------------------
 include/kvm/arm_pmu.h              |  1 -
 3 files changed, 22 insertions(+), 21 deletions(-)


base-commit: 5bc55a333a2f7316b58edc7573e8e893f7acb532

Comments

Oliver Upton Feb. 4, 2025, 11:52 p.m. UTC | #1

Hi Colton,

On Tue, Feb 04, 2025 at 07:57:07PM +0000, Colton Lewis wrote:
> asm/kvm_host.h includes asm/arm_pmu.h which includes perf/arm_pmuv3.h
> which includes asm/arm_pmuv3.h which includes asm/kvm_host.h This
> causes confusing compilation problems when trying to use anything in
> the chain.
> 
> Break the cycle by taking asm/kvm_host.h out of asm/arm_pmuv3.h
> because asm/kvm_host.h is huge and we only need a few functions from
> it. Move the required declarations to asm/arm_pmuv3.h.
> 
> Signed-off-by: Colton Lewis <[e-mail]>

Please do not move KVM namespaced functions into non-KVM headers. Having
a separate header for KVM<->PMUv3 driver interfaces is probably the
right thing to do, especially since you're going to be adding more with
partitioned PMU support.

Patch

diff --git a/arch/arm64/include/asm/arm_pmuv3.h b/arch/arm64/include/asm/arm_pmuv3.h
index 8a777dec8d88..89fd6abb7da6 100644
--- a/arch/arm64/include/asm/arm_pmuv3.h
+++ b/arch/arm64/include/asm/arm_pmuv3.h
@@ -6,11 +6,31 @@ 
 #ifndef __ASM_PMUV3_H
 #define __ASM_PMUV3_H
 
-#include <asm/kvm_host.h>
-
 #include <asm/cpufeature.h>
 #include <asm/sysreg.h>
 
+#include <linux/perf_event.h>
+
+#ifdef CONFIG_KVM
+void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr);
+void kvm_clr_pmu_events(u64 clr);
+bool kvm_set_pmuserenr(u64 val);
+#else
+static inline void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr) {}
+static inline void kvm_clr_pmu_events(u64 clr) {}
+static inline bool kvm_set_pmuserenr(u64 val)
+{
+	return false;
+}
+#endif
+
+static inline bool kvm_pmu_counter_deferred(struct perf_event_attr *attr)
+{
+	return (!has_vhe() && attr->exclude_host);
+}
+
+void kvm_vcpu_pmu_resync_el0(void);
+
 #define RETURN_READ_PMEVCNTRN(n) \
 	return read_sysreg(pmevcntr##n##_el0)
 static inline unsigned long read_pmevcntrn(int n)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e18e9244d17a..3eeb762944c9 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -1362,28 +1362,10 @@  void kvm_arch_vcpu_ctxflush_fp(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu);
 
-static inline bool kvm_pmu_counter_deferred(struct perf_event_attr *attr)
-{
-	return (!has_vhe() && attr->exclude_host);
-}
-
 /* Flags for host debug state */
 void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu);
 
-#ifdef CONFIG_KVM
-void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr);
-void kvm_clr_pmu_events(u64 clr);
-bool kvm_set_pmuserenr(u64 val);
-#else
-static inline void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr) {}
-static inline void kvm_clr_pmu_events(u64 clr) {}
-static inline bool kvm_set_pmuserenr(u64 val)
-{
-	return false;
-}
-#endif
-
 void kvm_vcpu_load_vhe(struct kvm_vcpu *vcpu);
 void kvm_vcpu_put_vhe(struct kvm_vcpu *vcpu);
 
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 147bd3ee4f7b..2c78b1b1a9bb 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -74,7 +74,6 @@  int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu);
 struct kvm_pmu_events *kvm_get_pmu_events(void);
 void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu);
 void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu);
-void kvm_vcpu_pmu_resync_el0(void);
 
 #define kvm_vcpu_has_pmu(vcpu)					\
 	(vcpu_has_feature(vcpu, KVM_ARM_VCPU_PMU_V3))