[PATCH 4/9] perf: arm_pmuv3: Prepare for more than 32 counters

Rob Herring (Arm)
2024-06-07T20:32:41Z

Various PMUv3 registers which are a mask of counters are 64-bit
registers, but the accessor functions take a u32. This has been fine as
the upper 32-bits have been RES0 as there has been a maximum of 32
counters prior to Armv9.4/8.9. With Armv9.4/8.9, a 33rd counter is
added. Update the accessor functions to use a u64 instead.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
arch/arm64/include/asm/arm_pmuv3.h | 12 ++++++------
arch/arm64/include/asm/kvm_host.h | 8 ++++----
arch/arm64/kvm/pmu.c | 8 ++++----
drivers/perf/arm_pmuv3.c | 40 ++++++++++++++++++++------------------
include/kvm/arm_pmu.h | 4 ++--
5 files changed, 37 insertions(+), 35 deletions(-)

diff --git a/arch/arm64/include/asm/arm_pmuv3.h b/arch/arm64/include/asm/arm_pmuv3.h
index c27404fa4418..e96ce7900fc7 100644
--- a/arch/arm64/include/asm/arm_pmuv3.h
+++ b/arch/arm64/include/asm/arm_pmuv3.h
@@ -71,22 +71,22 @@ static inline u64 read_pmccntr(void)
return read_sysreg(pmccntr_el0);
}

-static inline void write_pmcntenset(u32 val)
+static inline void write_pmcntenset(u64 val)
{
write_sysreg(val, pmcntenset_el0);
}

-static inline void write_pmcntenclr(u32 val)
+static inline void write_pmcntenclr(u64 val)
{
write_sysreg(val, pmcntenclr_el0);
}

-static inline void write_pmintenset(u32 val)
+static inline void write_pmintenset(u64 val)
{
write_sysreg(val, pmintenset_el1);
}

-static inline void write_pmintenclr(u32 val)
+static inline void write_pmintenclr(u64 val)
{
write_sysreg(val, pmintenclr_el1);
}
@@ -96,12 +96,12 @@ static inline void write_pmccfiltr(u64 val)
write_sysreg(val, pmccfiltr_el0);
}

-static inline void write_pmovsclr(u32 val)
+static inline void write_pmovsclr(u64 val)
{
write_sysreg(val, pmovsclr_el0);
}

-static inline u32 read_pmovsclr(void)
+static inline u64 read_pmovsclr(void)
{
return read_sysreg(pmovsclr_el0);
}
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 8170c04fde91..6243a01d9d26 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -1267,12 +1267,12 @@ 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(u32 set, struct perf_event_attr *attr);
-void kvm_clr_pmu_events(u32 clr);
+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(u32 set, struct perf_event_attr *attr) {}
-static inline void kvm_clr_pmu_events(u32 clr) {}
+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;
diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c
index 329819806096..e633b4434c6a 100644
--- a/arch/arm64/kvm/pmu.c
+++ b/arch/arm64/kvm/pmu.c
@@ -35,7 +35,7 @@ struct kvm_pmu_events *kvm_get_pmu_events(void)
* Add events to track that we may want to switch at guest entry/exit
* time.
*/
-void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr)
+void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr)
{
struct kvm_pmu_events *pmu = kvm_get_pmu_events();

@@ -51,7 +51,7 @@ void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr)
/*
* Stop tracking events
*/
-void kvm_clr_pmu_events(u32 clr)
+void kvm_clr_pmu_events(u64 clr)
{
struct kvm_pmu_events *pmu = kvm_get_pmu_events();

@@ -176,7 +176,7 @@ static void kvm_vcpu_pmu_disable_el0(unsigned long events)
void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu)
{
struct kvm_pmu_events *pmu;
- u32 events_guest, events_host;
+ u64 events_guest, events_host;

if (!kvm_arm_support_pmu_v3() || !has_vhe())
return;
@@ -197,7 +197,7 @@ void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu)
void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu)
{
struct kvm_pmu_events *pmu;
- u32 events_guest, events_host;
+ u64 events_guest, events_host;

if (!kvm_arm_support_pmu_v3() || !has_vhe())
return;
diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index 80202346fc7a..3b49144f3a58 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -502,14 +502,14 @@ static void armv8pmu_pmcr_write(u64 val)
write_pmcr(val);
}

-static int armv8pmu_has_overflowed(u32 pmovsr)
+static int armv8pmu_has_overflowed(u64 pmovsr)
{
- return pmovsr & ARMV8_PMU_OVERFLOWED_MASK;
+ return !!(pmovsr & ARMV8_PMU_OVERFLOWED_MASK);
}

-static int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
+static int armv8pmu_counter_has_overflowed(u64 pmnc, int idx)
{
- return pmnc & BIT(idx);
+ return !!(pmnc & BIT(idx));
}

static u64 armv8pmu_read_evcntr(int idx)
@@ -648,17 +648,17 @@ static void armv8pmu_write_event_type(struct perf_event *event)
}
}

-static u32 armv8pmu_event_cnten_mask(struct perf_event *event)
+static u64 armv8pmu_event_cnten_mask(struct perf_event *event)
{
int counter = event->hw.idx;
- u32 mask = BIT(counter);
+ u64 mask = BIT(counter);

if (armv8pmu_event_is_chained(event))
mask |= BIT(counter - 1);
return mask;
}

-static void armv8pmu_enable_counter(u32 mask)
+static void armv8pmu_enable_counter(u64 mask)
{
/*
* Make sure event configuration register writes are visible before we
@@ -671,7 +671,7 @@ static void armv8pmu_enable_counter(u32 mask)
static void armv8pmu_enable_event_counter(struct perf_event *event)
{
struct perf_event_attr *attr = &event->attr;
- u32 mask = armv8pmu_event_cnten_mask(event);
+ u64 mask = armv8pmu_event_cnten_mask(event);

kvm_set_pmu_events(mask, attr);

@@ -680,7 +680,7 @@ static void armv8pmu_enable_event_counter(struct perf_event *event)
armv8pmu_enable_counter(mask);
}

-static void armv8pmu_disable_counter(u32 mask)
+static void armv8pmu_disable_counter(u64 mask)
{
write_pmcntenclr(mask);
/*
@@ -693,7 +693,7 @@ static void armv8pmu_disable_counter(u32 mask)
static void armv8pmu_disable_event_counter(struct perf_event *event)
{
struct perf_event_attr *attr = &event->attr;
- u32 mask = armv8pmu_event_cnten_mask(event);
+ u64 mask = armv8pmu_event_cnten_mask(event);

kvm_clr_pmu_events(mask);

@@ -702,7 +702,7 @@ static void armv8pmu_disable_event_counter(struct perf_event *event)
armv8pmu_disable_counter(mask);
}

-static void armv8pmu_enable_intens(u32 mask)
+static void armv8pmu_enable_intens(u64 mask)
{
write_pmintenset(mask);
}
@@ -712,7 +712,7 @@ static void armv8pmu_enable_event_irq(struct perf_event *event)
armv8pmu_enable_intens(BIT(event->hw.idx));
}

-static void armv8pmu_disable_intens(u32 mask)
+static void armv8pmu_disable_intens(u64 mask)
{
write_pmintenclr(mask);
isb();
@@ -726,9 +726,9 @@ static void armv8pmu_disable_event_irq(struct perf_event *event)
armv8pmu_disable_intens(BIT(event->hw.idx));
}

-static u32 armv8pmu_getreset_flags(void)
+static u64 armv8pmu_getreset_flags(void)
{
- u32 value;
+ u64 value;

/* Read */
value = read_pmovsclr();
@@ -823,7 +823,7 @@ static void armv8pmu_stop(struct arm_pmu *cpu_pmu)

static irqreturn_t armv8pmu_handle_irq(struct arm_pmu *cpu_pmu)
{
- u32 pmovsr;
+ u64 pmovsr;
struct perf_sample_data data;
struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
struct pt_regs *regs;
@@ -1035,14 +1035,16 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event,
static void armv8pmu_reset(void *info)
{
struct arm_pmu *cpu_pmu = (struct arm_pmu *)info;
- u64 pmcr;
+ u64 pmcr, mask;
+
+ bitmap_to_arr64(&mask, cpu_pmu->cntr_mask, ARMPMU_MAX_HWEVENTS);

/* The counter and interrupt enable registers are unknown at reset. */
- armv8pmu_disable_counter(U32_MAX);
- armv8pmu_disable_intens(U32_MAX);
+ armv8pmu_disable_counter(mask);
+ armv8pmu_disable_intens(mask);

/* Clear the counters we flip at guest entry/exit */
- kvm_clr_pmu_events(U32_MAX);
+ kvm_clr_pmu_events(mask);

/*
* Initialize & Reset PMNC. Request overflow interrupt for
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 35d4ca4f6122..334d7c5503cf 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -19,8 +19,8 @@ struct kvm_pmc {
};

struct kvm_pmu_events {
- u32 events_host;
- u32 events_guest;
+ u64 events_host;
+ u64 events_guest;
};

struct kvm_pmu {

--
2.43.0