drivers/perf: arm_pmu: rework per-cpu allocation

For historical reasons, we allocate per-cpu data associated with a PMU
rather late, in cpu_pmu_init, after we've parsed whatever hardware
information we were provided with.

In order to allow use to store some per-cpu data early in the probe
path, we need to allocate (and initialise) the per-cpu data earlier.
This patch reworks the way we allocate the pmu and associated per-cpu
data in order to make that possible.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: make armpmu_{alloc,free} static
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Mark Rutland 2017-03-10 10:46:13 +00:00 committed by Will Deacon
parent 5d3fa803b1
commit 2681f01842

View File

@ -828,29 +828,16 @@ static inline void cpu_pm_pmu_unregister(struct arm_pmu *cpu_pmu) { }
static int cpu_pmu_init(struct arm_pmu *cpu_pmu)
{
int err;
int cpu;
struct pmu_hw_events __percpu *cpu_hw_events;
cpu_hw_events = alloc_percpu(struct pmu_hw_events);
if (!cpu_hw_events)
return -ENOMEM;
err = cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING,
&cpu_pmu->node);
if (err)
goto out_free;
goto out;
err = cpu_pm_pmu_register(cpu_pmu);
if (err)
goto out_unregister;
for_each_possible_cpu(cpu) {
struct pmu_hw_events *events = per_cpu_ptr(cpu_hw_events, cpu);
raw_spin_lock_init(&events->pmu_lock);
events->percpu_pmu = cpu_pmu;
}
cpu_pmu->hw_events = cpu_hw_events;
cpu_pmu->request_irq = cpu_pmu_request_irq;
cpu_pmu->free_irq = cpu_pmu_free_irq;
@ -876,8 +863,7 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu)
out_unregister:
cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING,
&cpu_pmu->node);
out_free:
free_percpu(cpu_hw_events);
out:
return err;
}
@ -886,7 +872,6 @@ static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu)
cpu_pm_pmu_unregister(cpu_pmu);
cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING,
&cpu_pmu->node);
free_percpu(cpu_pmu->hw_events);
}
/*
@ -1008,6 +993,45 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu)
return 0;
}
static struct arm_pmu *armpmu_alloc(void)
{
struct arm_pmu *pmu;
int cpu;
pmu = kzalloc(sizeof(*pmu), GFP_KERNEL);
if (!pmu) {
pr_info("failed to allocate PMU device!\n");
goto out;
}
pmu->hw_events = alloc_percpu(struct pmu_hw_events);
if (!pmu->hw_events) {
pr_info("failed to allocate per-cpu PMU data.\n");
goto out_free_pmu;
}
for_each_possible_cpu(cpu) {
struct pmu_hw_events *events;
events = per_cpu_ptr(pmu->hw_events, cpu);
raw_spin_lock_init(&events->pmu_lock);
events->percpu_pmu = pmu;
}
return pmu;
out_free_pmu:
kfree(pmu);
out:
return NULL;
}
static void armpmu_free(struct arm_pmu *pmu)
{
free_percpu(pmu->hw_events);
kfree(pmu);
}
int arm_pmu_device_probe(struct platform_device *pdev,
const struct of_device_id *of_table,
const struct pmu_probe_info *probe_table)
@ -1018,11 +1042,9 @@ int arm_pmu_device_probe(struct platform_device *pdev,
struct arm_pmu *pmu;
int ret = -ENODEV;
pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
if (!pmu) {
pr_info("failed to allocate PMU device!\n");
pmu = armpmu_alloc();
if (!pmu)
return -ENOMEM;
}
armpmu_init(pmu);
@ -1076,7 +1098,7 @@ out_free:
pr_info("%s: failed to register PMU devices!\n",
of_node_full_name(node));
kfree(pmu->irq_affinity);
kfree(pmu);
armpmu_free(pmu);
return ret;
}