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ARM: perf: check ARMv7 counter validity on a per-pmu basis
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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>
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Sudeep KarkadaNagesha authored and Will Deacon committed Nov 9, 2012
1 parent ed6f2a5 commit 7279adb
Showing 1 changed file with 30 additions and 64 deletions.
94 changes: 30 additions & 64 deletions arch/arm/kernel/perf_event_v7.c
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Original file line number Diff line number Diff line change
Expand Up @@ -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)
Expand Down Expand Up @@ -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();

Expand All @@ -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)
Expand All @@ -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)
Expand All @@ -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. */
Expand All @@ -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;
Expand All @@ -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",
Expand All @@ -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.
Expand Down Expand Up @@ -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
*/
Expand Down

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