[tip:perf/core] perf/x86/intel/rapl: Make PMU lock raw

From: tip-bot for Thomas Gleixner
Date: Mon Feb 29 2016 - 06:13:11 EST


Commit-ID: a208749c642618b6c106874153906b53f8e2ded9
Gitweb: http://git.kernel.org/tip/a208749c642618b6c106874153906b53f8e2ded9
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Mon, 22 Feb 2016 22:19:25 +0000
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 29 Feb 2016 09:35:25 +0100

perf/x86/intel/rapl: Make PMU lock raw

This lock is taken in hard interrupt context even on Preempt-RT. Make it raw
so RT does not have to patch it.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Andi Kleen <andi.kleen@xxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Harish Chegondi <harish.chegondi@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20160222221012.669411833@xxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/events/intel/rapl.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/events/intel/rapl.c b/arch/x86/events/intel/rapl.c
index ba5043b..2934999 100644
--- a/arch/x86/events/intel/rapl.c
+++ b/arch/x86/events/intel/rapl.c
@@ -120,7 +120,7 @@ static struct perf_pmu_events_attr event_attr_##v = { \
};

struct rapl_pmu {
- spinlock_t lock;
+ raw_spinlock_t lock;
int n_active;
struct list_head active_list;
struct pmu *pmu;
@@ -210,12 +210,12 @@ static enum hrtimer_restart rapl_hrtimer_handle(struct hrtimer *hrtimer)
if (!pmu->n_active)
return HRTIMER_NORESTART;

- spin_lock_irqsave(&pmu->lock, flags);
+ raw_spin_lock_irqsave(&pmu->lock, flags);

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

- spin_unlock_irqrestore(&pmu->lock, flags);
+ raw_spin_unlock_irqrestore(&pmu->lock, flags);

hrtimer_forward_now(hrtimer, pmu->timer_interval);

@@ -252,9 +252,9 @@ static void rapl_pmu_event_start(struct perf_event *event, int mode)
struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
unsigned long flags;

- spin_lock_irqsave(&pmu->lock, flags);
+ raw_spin_lock_irqsave(&pmu->lock, flags);
__rapl_pmu_event_start(pmu, event);
- spin_unlock_irqrestore(&pmu->lock, flags);
+ raw_spin_unlock_irqrestore(&pmu->lock, flags);
}

static void rapl_pmu_event_stop(struct perf_event *event, int mode)
@@ -263,7 +263,7 @@ static void rapl_pmu_event_stop(struct perf_event *event, int mode)
struct hw_perf_event *hwc = &event->hw;
unsigned long flags;

- spin_lock_irqsave(&pmu->lock, flags);
+ raw_spin_lock_irqsave(&pmu->lock, flags);

/* mark event as deactivated and stopped */
if (!(hwc->state & PERF_HES_STOPPED)) {
@@ -288,7 +288,7 @@ static void rapl_pmu_event_stop(struct perf_event *event, int mode)
hwc->state |= PERF_HES_UPTODATE;
}

- spin_unlock_irqrestore(&pmu->lock, flags);
+ raw_spin_unlock_irqrestore(&pmu->lock, flags);
}

static int rapl_pmu_event_add(struct perf_event *event, int mode)
@@ -297,14 +297,14 @@ static int rapl_pmu_event_add(struct perf_event *event, int mode)
struct hw_perf_event *hwc = &event->hw;
unsigned long flags;

- spin_lock_irqsave(&pmu->lock, flags);
+ raw_spin_lock_irqsave(&pmu->lock, flags);

hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;

if (mode & PERF_EF_START)
__rapl_pmu_event_start(pmu, event);

- spin_unlock_irqrestore(&pmu->lock, flags);
+ raw_spin_unlock_irqrestore(&pmu->lock, flags);

return 0;
}
@@ -567,7 +567,7 @@ static int rapl_cpu_prepare(int cpu)
pmu = kzalloc_node(sizeof(*pmu), GFP_KERNEL, cpu_to_node(cpu));
if (!pmu)
return -1;
- spin_lock_init(&pmu->lock);
+ raw_spin_lock_init(&pmu->lock);

INIT_LIST_HEAD(&pmu->active_list);