[patch V2 23/28] x86/perf/intel/rapl: Refactor code some more

From: Thomas Gleixner
Date: Mon Feb 22 2016 - 06:11:13 EST


Split out code from init into seperate functions. Tidy up the code and get rid
of pointless comments. I wish there would be comments for code which is not
obvious....

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event_intel_rapl.c | 61 ++++++++++++++--------------
1 file changed, 31 insertions(+), 30 deletions(-)

Index: b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
===================================================================
--- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
@@ -110,7 +110,7 @@ static ssize_t __rapl_##_var##_show(stru
static struct kobj_attribute format_attr_##_var = \
__ATTR(_name, 0444, __rapl_##_var##_show, NULL)

-#define RAPL_CNTR_WIDTH 32 /* 32-bit rapl counters */
+#define RAPL_CNTR_WIDTH 32

#define RAPL_EVENT_ATTR_STR(_name, v, str) \
static struct perf_pmu_events_attr event_attr_##v = { \
@@ -120,15 +120,16 @@ static struct perf_pmu_events_attr event
};

struct rapl_pmu {
- spinlock_t lock;
- int n_active; /* number of active events */
- struct list_head active_list;
- struct pmu *pmu; /* pointer to rapl_pmu_class */
- ktime_t timer_interval; /* in ktime_t unit */
- struct hrtimer hrtimer;
+ spinlock_t lock;
+ int n_active;
+ struct list_head active_list;
+ struct pmu *pmu;
+ ktime_t timer_interval;
+ struct hrtimer hrtimer;
};

-static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly; /* 1/2^hw_unit Joule */
+ /* 1/2^hw_unit Joule */
+static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly;
static struct pmu rapl_pmu_class;
static cpumask_t rapl_cpu_mask;
static int rapl_cntr_mask;
@@ -200,11 +201,6 @@ static void rapl_start_hrtimer(struct ra
HRTIMER_MODE_REL_PINNED);
}

-static void rapl_stop_hrtimer(struct rapl_pmu *pmu)
-{
- hrtimer_cancel(&pmu->hrtimer);
-}
-
static enum hrtimer_restart rapl_hrtimer_handle(struct hrtimer *hrtimer)
{
struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
@@ -216,9 +212,8 @@ static enum hrtimer_restart rapl_hrtimer

spin_lock_irqsave(&pmu->lock, flags);

- list_for_each_entry(event, &pmu->active_list, active_entry) {
+ list_for_each_entry(event, &pmu->active_list, active_entry)
rapl_event_update(event);
- }

spin_unlock_irqrestore(&pmu->lock, flags);

@@ -275,7 +270,7 @@ static void rapl_pmu_event_stop(struct p
WARN_ON_ONCE(pmu->n_active <= 0);
pmu->n_active--;
if (pmu->n_active == 0)
- rapl_stop_hrtimer(pmu);
+ hrtimer_cancel(&pmu->hrtimer);

list_del(&event->active_entry);

@@ -542,7 +537,7 @@ static void rapl_cpu_exit(int cpu)
perf_pmu_migrate_context(pmu->pmu, cpu, target);

/* cancel overflow polling timer for CPU */
- rapl_stop_hrtimer(pmu);
+ hrtimer_cancel(&pmu->hrtimer);
}

static void rapl_cpu_init(int cpu)
@@ -698,6 +693,20 @@ static void __init rapl_advertise(void)
}
}

+static int __init rapl_prepare_cpus(void)
+{
+ unsigned int cpu;
+ int ret;
+
+ for_each_online_cpu(cpu) {
+ ret = rapl_cpu_prepare(cpu);
+ if (ret)
+ return ret;
+ rapl_cpu_init(cpu);
+ }
+ return 0;
+}
+
static void __init cleanup_rapl_pmus(void)
{
int cpu;
@@ -706,7 +715,7 @@ static void __init cleanup_rapl_pmus(voi
kfree(per_cpu(rapl_pmu, cpu));
}

-static const struct x86_cpu_id rapl_cpu_match[] = {
+static const struct x86_cpu_id rapl_cpu_match[] __initconst = {
[0] = { .vendor = X86_VENDOR_INTEL, .family = 6 },
[1] = {},
};
@@ -714,15 +723,11 @@ static const struct x86_cpu_id rapl_cpu_
static int __init rapl_pmu_init(void)
{
void (*quirk)(void) = NULL;
- int cpu, ret;
+ int ret;

- /*
- * check for Intel processor family 6
- */
if (!x86_match_cpu(rapl_cpu_match))
return -ENODEV;

- /* check supported CPU */
switch (boot_cpu_data.x86_model) {
case 42: /* Sandy Bridge */
case 58: /* Ivy Bridge */
@@ -751,7 +756,6 @@ static int __init rapl_pmu_init(void)
rapl_pmu_events_group.attrs = rapl_events_knl_attr;
break;
default:
- /* unsupported */
return -ENODEV;
}

@@ -761,12 +765,9 @@ static int __init rapl_pmu_init(void)

cpu_notifier_register_begin();

- for_each_online_cpu(cpu) {
- ret = rapl_cpu_prepare(cpu);
- if (ret)
- goto out;
- rapl_cpu_init(cpu);
- }
+ ret = rapl_prepare_cpus();
+ if (ret)
+ goto out;

ret = perf_pmu_register(&rapl_pmu_class, "power", -1);
if (ret)