arm_pmu: factor out PMU matching

A subsequent patch will rework the ACPI probing of PMUs, and we'll need
to match a CPU with a known cpuid in two separate paths.

Factor out the matching logic into a helper function so that it can be
reused.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Pierre Gondois <pierre.gondois@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-and-tested-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/r/20220930111844.1522365-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
index a52a4aafd629f7bdee663a0433e0145492b5e241..99abea3b2cc9b2b26dcb3ca319b6b67053630685 100644 (file)
--- a/drivers/perf/arm_pmu_acpi.c
+++ b/drivers/perf/arm_pmu_acpi.c
@@ -187,7 +187,7 @@ out_err:
        return err;
 }
 
-static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
+static struct arm_pmu *arm_pmu_acpi_find_pmu(void)
 {
        unsigned long cpuid = read_cpuid_id();
        struct arm_pmu *pmu;
@@ -201,6 +201,17 @@ static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
                return pmu;
        }
 
+       return NULL;
+}
+
+static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
+{
+       struct arm_pmu *pmu;
+
+       pmu = arm_pmu_acpi_find_pmu();
+       if (pmu)
+               return pmu;
+
        pmu = armpmu_alloc_atomic();
        if (!pmu) {
                pr_warn("Unable to allocate PMU for CPU%d\n",
@@ -208,7 +219,7 @@ static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void)
                return NULL;
        }
 
-       pmu->acpi_cpuid = cpuid;
+       pmu->acpi_cpuid = read_cpuid_id();
 
        return pmu;
 }