arm_pmu: acpi: request IRQs up-front

We can't request IRQs in atomic context, so for ACPI systems we'll have
to request them up-front, and later associate them with CPUs.

This patch reorganises the arm_pmu code to do so. As we no longer have
the arm_pmu structure at probe time, a number of prototypes need to be
adjusted, requiring changes to the common arm_pmu code and arm_pmu
platform code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Mark Rutland 2017-10-09 17:09:05 +01:00 committed by Will Deacon
parent 84b4be57ae
commit 167e61438d
4 changed files with 23 additions and 38 deletions

View File

@ -534,7 +534,7 @@ static int armpmu_count_irq_users(const int irq)
return count;
}
void armpmu_free_cpu_irq(int irq, int cpu)
void armpmu_free_irq(int irq, int cpu)
{
if (per_cpu(cpu_irq, cpu) == 0)
return;
@ -549,15 +549,7 @@ void armpmu_free_cpu_irq(int irq, int cpu)
per_cpu(cpu_irq, cpu) = 0;
}
void armpmu_free_irq(struct arm_pmu *armpmu, int cpu)
{
struct pmu_hw_events __percpu *hw_events = armpmu->hw_events;
int irq = per_cpu(hw_events->irq, cpu);
armpmu_free_cpu_irq(irq, cpu);
}
int armpmu_request_cpu_irq(int irq, int cpu)
int armpmu_request_irq(int irq, int cpu)
{
int err = 0;
const irq_handler_t handler = armpmu_dispatch_irq;
@ -598,16 +590,6 @@ int armpmu_request_cpu_irq(int irq, int cpu)
return err;
}
int armpmu_request_irq(struct arm_pmu *armpmu, int cpu)
{
struct pmu_hw_events __percpu *hw_events = armpmu->hw_events;
int irq = per_cpu(hw_events->irq, cpu);
if (!irq)
return 0;
return armpmu_request_cpu_irq(irq, cpu);
}
static int armpmu_get_cpu_irq(struct arm_pmu *pmu, int cpu)
{
struct pmu_hw_events __percpu *hw_events = pmu->hw_events;

View File

@ -89,7 +89,13 @@ static int arm_pmu_acpi_parse_irqs(void)
pr_warn("No ACPI PMU IRQ for CPU%d\n", cpu);
}
/*
* Log and request the IRQ so the core arm_pmu code can manage
* it. We'll have to sanity-check IRQs later when we associate
* them with their PMUs.
*/
per_cpu(pmu_irqs, cpu) = irq;
armpmu_request_irq(irq, cpu);
}
return 0;
@ -204,14 +210,6 @@ static int arm_pmu_acpi_cpu_starting(unsigned int cpu)
cpumask_set_cpu(cpu, &pmu->supported_cpus);
/*
* Log and request the IRQ so the core arm_pmu code can manage it. In
* some situations (e.g. mismatched PPIs), we may fail to request the
* IRQ. However, it may be too late for us to do anything about it.
* The common ARM PMU code will log a warning in this case.
*/
armpmu_request_irq(pmu, cpu);
/*
* Ideally, we'd probe the PMU here when we find the first matching
* CPU. We can't do that for several reasons; see the comment in
@ -281,11 +279,6 @@ static int arm_pmu_acpi_init(void)
if (acpi_disabled)
return 0;
/*
* We can't request IRQs yet, since we don't know the cookie value
* until we know which CPUs share the same logical PMU. We'll handle
* that in arm_pmu_acpi_cpu_starting().
*/
ret = arm_pmu_acpi_parse_irqs();
if (ret)
return ret;

View File

@ -159,10 +159,15 @@ static int pmu_parse_irqs(struct arm_pmu *pmu)
static int armpmu_request_irqs(struct arm_pmu *armpmu)
{
struct pmu_hw_events __percpu *hw_events = armpmu->hw_events;
int cpu, err;
for_each_cpu(cpu, &armpmu->supported_cpus) {
err = armpmu_request_irq(armpmu, cpu);
int irq = per_cpu(hw_events->irq, cpu);
if (!irq)
continue;
err = armpmu_request_irq(irq, cpu);
if (err)
break;
}
@ -173,9 +178,13 @@ static int armpmu_request_irqs(struct arm_pmu *armpmu)
static void armpmu_free_irqs(struct arm_pmu *armpmu)
{
int cpu;
struct pmu_hw_events __percpu *hw_events = armpmu->hw_events;
for_each_cpu(cpu, &armpmu->supported_cpus)
armpmu_free_irq(armpmu, cpu);
for_each_cpu(cpu, &armpmu->supported_cpus) {
int irq = per_cpu(hw_events->irq, cpu);
armpmu_free_irq(irq, cpu);
}
}
int arm_pmu_device_probe(struct platform_device *pdev,

View File

@ -14,6 +14,7 @@
#include <linux/interrupt.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <linux/sysfs.h>
#include <asm/cputype.h>
@ -159,8 +160,8 @@ struct arm_pmu *armpmu_alloc(void);
struct arm_pmu *armpmu_alloc_atomic(void);
void armpmu_free(struct arm_pmu *pmu);
int armpmu_register(struct arm_pmu *pmu);
int armpmu_request_irq(struct arm_pmu *armpmu, int cpu);
void armpmu_free_irq(struct arm_pmu *armpmu, int cpu);
int armpmu_request_irq(int irq, int cpu);
void armpmu_free_irq(int irq, int cpu);
#define ARMV8_PMU_PDEV_NAME "armv8-pmu"