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ARCv2: perf: SMP support 

* split off pmu info into singleton and per-cpu bits
* setup PMU on all cores

Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
hifive-unleashed-5.1
Alexey Brodkin 2015-08-24 14:03:30 +03:00 committed by Vineet Gupta
parent e6b1d126bb
commit e525c37f84
1 changed files with 55 additions and 16 deletions
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71
arch/arc/kernel/perf_event.c
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@ -21,10 +21,22 @@
struct arc_pmu {
struct pmu pmu;
unsigned int irq;
int n_counters;
unsigned long used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)];
u64 max_period;
int ev_hw_idx[PERF_COUNT_ARC_HW_MAX];
};
struct arc_pmu_cpu {
/*
* A 1 bit for an index indicates that the counter is being used for
* an event. A 0 means that the counter can be used.
*/
unsigned long used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)];
/*
* The events that are active on the PMU for the given index.
*/
struct perf_event *act_counter[ARC_PERF_MAX_COUNTERS];
};
@ -67,6 +79,7 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
}
static struct arc_pmu *arc_pmu;
static DEFINE_PER_CPU(struct arc_pmu_cpu, arc_pmu_cpu);
/* read counter #idx; note that counter# != event# on ARC! */
static uint64_t arc_pmu_read_counter(int idx)
@ -304,10 +317,12 @@ static void arc_pmu_stop(struct perf_event *event, int flags)
static void arc_pmu_del(struct perf_event *event, int flags)
{
arc_pmu_stop(event, PERF_EF_UPDATE);
__clear_bit(event->hw.idx, arc_pmu->used_mask);
struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
arc_pmu->act_counter[event->hw.idx] = 0;
arc_pmu_stop(event, PERF_EF_UPDATE);
__clear_bit(event->hw.idx, pmu_cpu->used_mask);
pmu_cpu->act_counter[event->hw.idx] = 0;
perf_event_update_userpage(event);
}
@ -315,22 +330,23 @@ static void arc_pmu_del(struct perf_event *event, int flags)
/* allocate hardware counter and optionally start counting */
static int arc_pmu_add(struct perf_event *event, int flags)
{
struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
if (__test_and_set_bit(idx, arc_pmu->used_mask)) {
idx = find_first_zero_bit(arc_pmu->used_mask,
if (__test_and_set_bit(idx, pmu_cpu->used_mask)) {
idx = find_first_zero_bit(pmu_cpu->used_mask,
arc_pmu->n_counters);
if (idx == arc_pmu->n_counters)
return -EAGAIN;
__set_bit(idx, arc_pmu->used_mask);
__set_bit(idx, pmu_cpu->used_mask);
hwc->idx = idx;
}
write_aux_reg(ARC_REG_PCT_INDEX, idx);
arc_pmu->act_counter[idx] = event;
pmu_cpu->act_counter[idx] = event;
if (is_sampling_event(event)) {
/* Mimic full counter overflow as other arches do */
@ -357,7 +373,7 @@ static int arc_pmu_add(struct perf_event *event, int flags)
static irqreturn_t arc_pmu_intr(int irq, void *dev)
{
struct perf_sample_data data;
struct arc_pmu *arc_pmu = (struct arc_pmu *)dev;
struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
struct pt_regs *regs;
int active_ints;
int idx;
@ -369,7 +385,7 @@ static irqreturn_t arc_pmu_intr(int irq, void *dev)
regs = get_irq_regs();
for (idx = 0; idx < arc_pmu->n_counters; idx++) {
struct perf_event *event = arc_pmu->act_counter[idx];
struct perf_event *event = pmu_cpu->act_counter[idx];
struct hw_perf_event *hwc;
if (!(active_ints & (1 << idx)))
@ -412,6 +428,17 @@ static irqreturn_t arc_pmu_intr(int irq, void *dev)
#endif /* CONFIG_ISA_ARCV2 */
void arc_cpu_pmu_irq_init(void)
{
struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
arc_request_percpu_irq(arc_pmu->irq, smp_processor_id(), arc_pmu_intr,
"ARC perf counters", pmu_cpu);
/* Clear all pending interrupt flags */
write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);
}
static int arc_pmu_device_probe(struct platform_device *pdev)
{
struct arc_reg_pct_build pct_bcr;
@ -488,18 +515,30 @@ static int arc_pmu_device_probe(struct platform_device *pdev)
if (has_interrupts) {
int irq = platform_get_irq(pdev, 0);
unsigned long flags;
if (irq < 0) {
pr_err("Cannot get IRQ number for the platform\n");
return -ENODEV;
}
ret = devm_request_irq(&pdev->dev, irq, arc_pmu_intr, 0,
"arc-pmu", arc_pmu);
if (ret) {
pr_err("could not allocate PMU IRQ\n");
return ret;
}
arc_pmu->irq = irq;
/*
* arc_cpu_pmu_irq_init() needs to be called on all cores for
* their respective local PMU.
* However we use opencoded on_each_cpu() to ensure it is called
* on core0 first, so that arc_request_percpu_irq() sets up
* AUTOEN etc. Otherwise enable_percpu_irq() fails to enable
* perf IRQ on non master cores.
* see arc_request_percpu_irq()
*/
preempt_disable();
local_irq_save(flags);
arc_cpu_pmu_irq_init();
local_irq_restore(flags);
smp_call_function((smp_call_func_t)arc_cpu_pmu_irq_init, 0, 1);
preempt_enable();
/* Clean all pending interrupt flags */
write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);