ARM: perf: check ARMv7 counter validity on a per-pmu basis

Multi-cluster ARMv7 systems may have CPU PMUs with different number of
counters.

This patch updates armv7_pmnc_counter_valid so that it takes a pmu
argument and checks the counter validity against that. We also remove a
number of redundant counter checks whether the current PMU is not easily
retrievable.

Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

1 files changed, 30 insertions, 64 deletions

diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index 1183c81087b2..7d0cce85d17e 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -736,7 +736,8 @@ static const unsigned armv7_a7_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
  */
 #define ARMV7_IDX_CYCLE_COUNTER 0
 #define ARMV7_IDX_COUNTER0      1
-#define ARMV7_IDX_COUNTER_LAST  (ARMV7_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)
+#define ARMV7_IDX_COUNTER_LAST(cpu_pmu) \
+        (ARMV7_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)
 
 #define ARMV7_MAX_COUNTERS      32
 #define ARMV7_COUNTER_MASK      (ARMV7_MAX_COUNTERS - 1)
@@ -802,38 +803,20 @@ static inline int armv7_pmnc_has_overflowed(u32 pmnc)
         return pmnc & ARMV7_OVERFLOWED_MASK;
 }
 
-static inline int armv7_pmnc_counter_valid(int idx)
+static inline int armv7_pmnc_counter_valid(struct arm_pmu *cpu_pmu, int idx)
 {
-        return idx >= ARMV7_IDX_CYCLE_COUNTER && idx <= ARMV7_IDX_COUNTER_LAST;
+        return idx >= ARMV7_IDX_CYCLE_COUNTER &&
+                idx <= ARMV7_IDX_COUNTER_LAST(cpu_pmu);
 }
 
 static inline int armv7_pmnc_counter_has_overflowed(u32 pmnc, int idx)
 {
-        int ret = 0;
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u checking wrong counter %d overflow status\n",
-                        smp_processor_id(), idx);
-        } else {
-                counter = ARMV7_IDX_TO_COUNTER(idx);
-                ret = pmnc & BIT(counter);
-        }
-
-        return ret;
+        return pmnc & BIT(ARMV7_IDX_TO_COUNTER(idx));
 }
 
 static inline int armv7_pmnc_select_counter(int idx)
 {
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u selecting wrong PMNC counter %d\n",
-                        smp_processor_id(), idx);
-                return -EINVAL;
-        }
-
-        counter = ARMV7_IDX_TO_COUNTER(idx);
+        u32 counter = ARMV7_IDX_TO_COUNTER(idx);
         asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (counter));
         isb();
 
@@ -842,11 +825,12 @@ static inline int armv7_pmnc_select_counter(int idx)
 
 static inline u32 armv7pmu_read_counter(struct perf_event *event)
 {
+        struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
         struct hw_perf_event *hwc = &event->hw;
         int idx = hwc->idx;
         u32 value = 0;
 
-        if (!armv7_pmnc_counter_valid(idx))
+        if (!armv7_pmnc_counter_valid(cpu_pmu, idx))
                 pr_err("CPU%u reading wrong counter %d\n",
                         smp_processor_id(), idx);
         else if (idx == ARMV7_IDX_CYCLE_COUNTER)
@@ -859,10 +843,11 @@ static inline u32 armv7pmu_read_counter(struct perf_event *event)
 
 static inline void armv7pmu_write_counter(struct perf_event *event, u32 value)
 {
+        struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
         struct hw_perf_event *hwc = &event->hw;
         int idx = hwc->idx;
 
-        if (!armv7_pmnc_counter_valid(idx))
+        if (!armv7_pmnc_counter_valid(cpu_pmu, idx))
                 pr_err("CPU%u writing wrong counter %d\n",
                         smp_processor_id(), idx);
         else if (idx == ARMV7_IDX_CYCLE_COUNTER)
@@ -881,60 +866,28 @@ static inline void armv7_pmnc_write_evtsel(int idx, u32 val)
 
 static inline int armv7_pmnc_enable_counter(int idx)
 {
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u enabling wrong PMNC counter %d\n",
-                        smp_processor_id(), idx);
-                return -EINVAL;
-        }
-
-        counter = ARMV7_IDX_TO_COUNTER(idx);
+        u32 counter = ARMV7_IDX_TO_COUNTER(idx);
         asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (BIT(counter)));
         return idx;
 }
 
 static inline int armv7_pmnc_disable_counter(int idx)
 {
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u disabling wrong PMNC counter %d\n",
-                        smp_processor_id(), idx);
-                return -EINVAL;
-        }
-
-        counter = ARMV7_IDX_TO_COUNTER(idx);
+        u32 counter = ARMV7_IDX_TO_COUNTER(idx);
         asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (BIT(counter)));
         return idx;
 }
 
 static inline int armv7_pmnc_enable_intens(int idx)
 {
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
-                        smp_processor_id(), idx);
-                return -EINVAL;
-        }
-
-        counter = ARMV7_IDX_TO_COUNTER(idx);
+        u32 counter = ARMV7_IDX_TO_COUNTER(idx);
         asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (BIT(counter)));
         return idx;
 }
 
 static inline int armv7_pmnc_disable_intens(int idx)
 {
-        u32 counter;
-
-        if (!armv7_pmnc_counter_valid(idx)) {
-                pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
-                        smp_processor_id(), idx);
-                return -EINVAL;
-        }
-
-        counter = ARMV7_IDX_TO_COUNTER(idx);
+        u32 counter = ARMV7_IDX_TO_COUNTER(idx);
         asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (BIT(counter)));
         isb();
         /* Clear the overflow flag in case an interrupt is pending. */
@@ -959,7 +912,7 @@ static inline u32 armv7_pmnc_getreset_flags(void)
 }
 
 #ifdef DEBUG
-static void armv7_pmnc_dump_regs(void)
+static void armv7_pmnc_dump_regs(struct arm_pmu *cpu_pmu)
 {
         u32 val;
         unsigned int cnt;
@@ -984,7 +937,8 @@ static void armv7_pmnc_dump_regs(void)
         asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
         printk(KERN_INFO "CCNT  =0x%08x\n", val);
 
-        for (cnt = ARMV7_IDX_COUNTER0; cnt <= ARMV7_IDX_COUNTER_LAST; cnt++) {
+        for (cnt = ARMV7_IDX_COUNTER0;
+                        cnt <= ARMV7_IDX_COUNTER_LAST(cpu_pmu); cnt++) {
                 armv7_pmnc_select_counter(cnt);
                 asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
                 printk(KERN_INFO "CNT[%d] count =0x%08x\n",
@@ -1004,6 +958,12 @@ static void armv7pmu_enable_event(struct perf_event *event)
         struct pmu_hw_events *events = cpu_pmu->get_hw_events();
         int idx = hwc->idx;
 
+        if (!armv7_pmnc_counter_valid(cpu_pmu, idx)) {
+                pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
+                        smp_processor_id(), idx);
+                return;
+        }
+
         /*
          * Enable counter and interrupt, and set the counter to count
          * the event that we're interested in.
@@ -1044,6 +1004,12 @@ static void armv7pmu_disable_event(struct perf_event *event)
         struct pmu_hw_events *events = cpu_pmu->get_hw_events();
         int idx = hwc->idx;
 
+        if (!armv7_pmnc_counter_valid(cpu_pmu, idx)) {
+                pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
+                        smp_processor_id(), idx);
+                return;
+        }
+
         /*
          * Disable counter and interrupt
          */