[PATCH RT 06/14] perf/x86/intel/rapl: Make PMU lock raw

Steven Rostedt
2016-07-12T16:48:59Z

[-- Attachment #1: 0006-perf-x86-intel-rapl-Make-PMU-lock-raw.patch --]
[-- Type: text/plain, Size: 4131 bytes --]

3.14.72-rt76-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@linutronix.de>

Upstream commit: a208749c6426 ("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@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Cc: stable-rt@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221012.669411833@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/kernel/cpu/perf_event_intel_rapl.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_rapl.c b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
index 95700e52061d..4d270d910c33 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
@@ -98,7 +98,7 @@ static struct kobj_attribute format_attr_##_var = \
#define RAPL_CNTR_WIDTH 32 /* 32-bit rapl counters */

struct rapl_pmu {
- spinlock_t lock;
+ raw_spinlock_t lock;
int hw_unit; /* 1/2^hw_unit Joule */
int n_active; /* number of active events */
struct list_head active_list;
@@ -188,13 +188,13 @@ 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);

@@ -231,9 +231,9 @@ static void rapl_pmu_event_start(struct perf_event *event, int mode)
struct rapl_pmu *pmu = __get_cpu_var(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)
@@ -242,7 +242,7 @@ 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)) {
@@ -267,7 +267,7 @@ 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)
@@ -276,14 +276,14 @@ 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;
}
@@ -526,7 +526,7 @@ static int rapl_cpu_prepare(int cpu)
if (!pmu)
return -1;

- spin_lock_init(&pmu->lock);
+ raw_spin_lock_init(&pmu->lock);

INIT_LIST_HEAD(&pmu->active_list);

--
2.8.1