Re: [Intel-gfx] [PATCH] drm/i915/pmu: Check is pmu is closed before stopping event
On Thu, 19 Oct 2023, Umesh Nerlige Ramappa
wrote:
> When the driver unbinds, pmu is unregistered and i915->uabi_engines is
> set to RB_ROOT. Due to this, when i915 PMU tries to stop the engine
> events, it issues a warn_on because engine lookup fails.
>
> All perf hooks are taking care of this using a pmu->closed flag that is
> set when PMU unregisters. The stop event seems to have been left out.
>
> Check for pmu->closed in pmu_event_stop as well.
>
> Based on discussion here -
> https://patchwork.freedesktop.org/patch/492079/?series=105790&rev=2
>
> Signed-off-by: Umesh Nerlige Ramappa
> ---
> drivers/gpu/drm/i915/i915_pmu.c | 9 +
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 108b675088ba..f861863eb7c1 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -831,9 +831,18 @@ static void i915_pmu_event_start(struct perf_event
> *event, int flags)
>
> static void i915_pmu_event_stop(struct perf_event *event, int flags)
> {
> + struct drm_i915_private *i915 =
> + container_of(event->pmu, typeof(*i915), pmu.base);
> + struct i915_pmu *pmu = &i915->pmu;
This inspired me to write [1]. Please review.
BR,
Jani.
[1] https://patchwork.freedesktop.org/series/125464/
> +
> + if (pmu->closed)
> + goto out;
> +
> if (flags & PERF_EF_UPDATE)
> i915_pmu_event_read(event);
> i915_pmu_disable(event);
> +
> +out:
> event->hw.state = PERF_HES_STOPPED;
> }
--
Jani Nikula, Intel
[Intel-gfx] [PATCH] drm/i915/pmu: Check is pmu is closed before stopping event
When the driver unbinds, pmu is unregistered and i915->uabi_engines is
set to RB_ROOT. Due to this, when i915 PMU tries to stop the engine
events, it issues a warn_on because engine lookup fails.
All perf hooks are taking care of this using a pmu->closed flag that is
set when PMU unregisters. The stop event seems to have been left out.
Check for pmu->closed in pmu_event_stop as well.
Based on discussion here -
https://patchwork.freedesktop.org/patch/492079/?series=105790&rev=2
Signed-off-by: Umesh Nerlige Ramappa
---
drivers/gpu/drm/i915/i915_pmu.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index 108b675088ba..f861863eb7c1 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -831,9 +831,18 @@ static void i915_pmu_event_start(struct perf_event *event,
int flags)
static void i915_pmu_event_stop(struct perf_event *event, int flags)
{
+ struct drm_i915_private *i915 =
+ container_of(event->pmu, typeof(*i915), pmu.base);
+ struct i915_pmu *pmu = &i915->pmu;
+
+ if (pmu->closed)
+ goto out;
+
if (flags & PERF_EF_UPDATE)
i915_pmu_event_read(event);
i915_pmu_disable(event);
+
+out:
event->hw.state = PERF_HES_STOPPED;
}
--
2.38.1
[Intel-gfx] [PATCH] drm/i915/pmu: Check is pmu is closed before stopping event
When the driver unbinds, pmu is unregistered and i915->uabi_engines is
set to RB_ROOT. Due to this, when i915 PMU tries to stop the engine
events, it issues a warn_on because engine lookup fails.
All perf hooks are taking care of this using a pmu->closed flag that is
set when PMU unregisters. The stop event seems to have been left out.
Check for pmu->closed in pmu_event_stop as well.
Based on discussion here -
https://patchwork.freedesktop.org/patch/492079/?series=105790&rev=2
Signed-off-by: Umesh Nerlige Ramappa
---
drivers/gpu/drm/i915/i915_pmu.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index 108b675088ba..f861863eb7c1 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -831,9 +831,18 @@ static void i915_pmu_event_start(struct perf_event *event,
int flags)
static void i915_pmu_event_stop(struct perf_event *event, int flags)
{
+ struct drm_i915_private *i915 =
+ container_of(event->pmu, typeof(*i915), pmu.base);
+ struct i915_pmu *pmu = &i915->pmu;
+
+ if (pmu->closed)
+ goto out;
+
if (flags & PERF_EF_UPDATE)
i915_pmu_event_read(event);
i915_pmu_disable(event);
+
+out:
event->hw.state = PERF_HES_STOPPED;
}
--
2.38.1
