[RFC][PATCH 5/9] perf: arm, convert to new API pmu->init_event

[RFC][PATCH 5/9] perf: arm, convert to new API pmu->init_event

[Lin Ming]

perf: arm, convert to new API pmu->init_event

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
---
 arch/arm/kernel/perf_event.c |   28 +++++++++++++++-------------
 1 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 8400ddf..565f13a 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -270,13 +270,6 @@ out:
 	return err;
 }
 
-static struct pmu pmu = {
-	.enable	    = armpmu_enable,
-	.disable    = armpmu_disable,
-	.unthrottle = armpmu_unthrottle,
-	.read	    = armpmu_read,
-};
-
 static int
 validate_event(struct cpu_hw_events *cpuc,
 	       struct perf_event *event)
@@ -446,20 +439,19 @@ __hw_perf_event_init(struct perf_event *event)
 	return err;
 }
 
-struct pmu *
-hw_perf_event_init(struct perf_event *event)
+static int armpmu_init_event(struct perf_event *event)
 {
 	int err = 0;
 
 	if (!armpmu)
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 
 	event->destroy = hw_perf_event_destroy;
 
 	if (!atomic_inc_not_zero(&active_events)) {
 		if (atomic_read(&active_events) > perf_max_events) {
 			atomic_dec(&active_events);
-			return ERR_PTR(-ENOSPC);
+			return -ENOSPC;
 		}
 
 		mutex_lock(&pmu_reserve_mutex);
@@ -473,15 +465,23 @@ hw_perf_event_init(struct perf_event *event)
 	}
 
 	if (err)
-		return ERR_PTR(err);
+		return err;
 
 	err = __hw_perf_event_init(event);
 	if (err)
 		hw_perf_event_destroy(event);
 
-	return err ? ERR_PTR(err) : &pmu;
+	return err;
 }
 
+static struct pmu pmu = {
+	.enable	    = armpmu_enable,
+	.disable    = armpmu_disable,
+	.unthrottle = armpmu_unthrottle,
+	.read	    = armpmu_read,
+	.init_event  = armpmu_init_event,
+};
+
 void
 hw_perf_enable(void)
 {
@@ -2138,6 +2138,8 @@ init_hw_perf_events(void)
 		pr_info("enabled with %s PMU driver, %d counters available\n",
 			armpmu->name, armpmu->num_events);
 
+	perf_event_register_pmu(&pmu);
+
 	return 0;
 }
 arch_initcall(init_hw_perf_events);

Re: [RFC][PATCH 5/9] perf: arm, convert to new API pmu->init_event

[Russell King]

On Mon, May 10, 2010 at 05:27:52PM +0800, Lin Ming wrote:
> perf: arm, convert to new API pmu->init_event

Unfortunately, this seems to clash with a rework of the ARM PMU/oprofile
code.  You also really need to copy the guys doing this work, eg the
authors of arch/arm/kernel/perf_event.c - Will Deacon.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:

Re: [RFC][PATCH 5/9] perf: arm, convert to new API pmu->init_event

[Lin Ming]

On Mon, 2010-05-10 at 17:38 +0800, Russell King wrote:
> Unfortunately, this seems to clash with a rework of the ARM PMU/oprofile
> code.  You also really need to copy the guys doing this work, eg the
> authors of arch/arm/kernel/perf_event.c - Will Deacon.

(Add Will Deacon)

I'll check the rework of the ARM PMU/oprofile code.

Thanks.

On Mon, 2010-05-10 at 17:27 +0800, Lin Ming wrote:
> perf: arm, convert to new API pmu->init_event
> 
> Signed-off-by: Lin Ming <ming.m.lin@intel.com>
> ---
>  arch/arm/kernel/perf_event.c |   28 +++++++++++++++-------------
>  1 files changed, 15 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
> index 8400ddf..565f13a 100644
> --- a/arch/arm/kernel/perf_event.c
> +++ b/arch/arm/kernel/perf_event.c
> @@ -270,13 +270,6 @@ out:
>  	return err;
>  }
>  
> -static struct pmu pmu = {
> -	.enable	    = armpmu_enable,
> -	.disable    = armpmu_disable,
> -	.unthrottle = armpmu_unthrottle,
> -	.read	    = armpmu_read,
> -};
> -
>  static int
>  validate_event(struct cpu_hw_events *cpuc,
>  	       struct perf_event *event)
> @@ -446,20 +439,19 @@ __hw_perf_event_init(struct perf_event *event)
>  	return err;
>  }
>  
> -struct pmu *
> -hw_perf_event_init(struct perf_event *event)
> +static int armpmu_init_event(struct perf_event *event)
>  {
>  	int err = 0;
>  
>  	if (!armpmu)
> -		return ERR_PTR(-ENODEV);
> +		return -ENODEV;
>  
>  	event->destroy = hw_perf_event_destroy;
>  
>  	if (!atomic_inc_not_zero(&active_events)) {
>  		if (atomic_read(&active_events) > perf_max_events) {
>  			atomic_dec(&active_events);
> -			return ERR_PTR(-ENOSPC);
> +			return -ENOSPC;
>  		}
>  
>  		mutex_lock(&pmu_reserve_mutex);
> @@ -473,15 +465,23 @@ hw_perf_event_init(struct perf_event *event)
>  	}
>  
>  	if (err)
> -		return ERR_PTR(err);
> +		return err;
>  
>  	err = __hw_perf_event_init(event);
>  	if (err)
>  		hw_perf_event_destroy(event);
>  
> -	return err ? ERR_PTR(err) : &pmu;
> +	return err;
>  }
>  
> +static struct pmu pmu = {
> +	.enable	    = armpmu_enable,
> +	.disable    = armpmu_disable,
> +	.unthrottle = armpmu_unthrottle,
> +	.read	    = armpmu_read,
> +	.init_event  = armpmu_init_event,
> +};
> +
>  void
>  hw_perf_enable(void)
>  {
> @@ -2138,6 +2138,8 @@ init_hw_perf_events(void)
>  		pr_info("enabled with %s PMU driver, %d counters available\n",
>  			armpmu->name, armpmu->num_events);
>  
> +	perf_event_register_pmu(&pmu);
> +
>  	return 0;
>  }
>  arch_initcall(init_hw_perf_events);
> 

Re: [RFC][PATCH 5/9] perf: arm, convert to new API pmu->init_event

[Will Deacon]

Hi Lin [thanks to Russell for the CC],

On Mon, 2010-05-10 at 11:00 +0100, Lin Ming wrote:
> On Mon, 2010-05-10 at 17:27 +0800, Lin Ming wrote:
> > perf: arm, convert to new API pmu->init_event
> >
> > Signed-off-by: Lin Ming <ming.m.lin@intel.com>
> > ---
> >  arch/arm/kernel/perf_event.c |   28 +++++++++++++++-------------
> >  1 files changed, 15 insertions(+), 13 deletions(-)
> >
 
--------8<--------

The changes I've made to perf_event.c that result in conflicts
with this patch shouldn't cause you any trouble. If you rebase
the patch then everything should work as expected. Please CC me
when you submit the next iteration.

Cheers,

Will