Re: [PATCH v8 7/7] drm/panfrost: Switch to generic memory shrinker
Hello Steve, On 11/14/22 19:54, Steven Price wrote: > On 05/11/2022 23:27, Dmitry Osipenko wrote: >> Replace Panfrost's custom memory shrinker with a common drm-shmem >> memory shrinker. >> >> Signed-off-by: Dmitry Osipenko > > Sadly this triggers GPU faults under memory pressure - it looks > suspiciously like mappings are being freed while the jobs are still running. > > I'm not sure I understand how the generic shrinker replicates the > "gpu_usecount" atomic that Panfrost currently has, and I'm wondering if > that's the cause? > > Also just reverting this commit (so just patches 1-6) I can't actually > get Panfrost to purge any memory. So I don't think the changes (most > likely in patch 4) are quite right either. > > At the moment I don't have the time to investigate in detail. But if > you've any ideas for something specific I should look at I can run more > testing. Thank you for the testing! It just occurred to me that the shrinker callback lost the dma_resv_test_signaled() in comparison to the previous versions of this patchset. It appeared to me that the drm_gem_lru now checks whether reservation is busy, but it doesn't. I saw a similar page faults once in a while when was testing the Panfrost driver, but then couldn't reproduce the faults after applying the IOMMU unmap range fix that Robin made recently. I'll re-add the dma_resv_test_signaled() in v9, it was a luck that I didn't hit it much during my testing. -- Best regards, Dmitry
Re: [PATCH v8 7/7] drm/panfrost: Switch to generic memory shrinker
On 05/11/2022 23:27, Dmitry Osipenko wrote:
> Replace Panfrost's custom memory shrinker with a common drm-shmem
> memory shrinker.
>
> Signed-off-by: Dmitry Osipenko
Sadly this triggers GPU faults under memory pressure - it looks
suspiciously like mappings are being freed while the jobs are still running.
I'm not sure I understand how the generic shrinker replicates the
"gpu_usecount" atomic that Panfrost currently has, and I'm wondering if
that's the cause?
Also just reverting this commit (so just patches 1-6) I can't actually
get Panfrost to purge any memory. So I don't think the changes (most
likely in patch 4) are quite right either.
At the moment I don't have the time to investigate in detail. But if
you've any ideas for something specific I should look at I can run more
testing.
Steve
> ---
> drivers/gpu/drm/panfrost/Makefile | 1 -
> drivers/gpu/drm/panfrost/panfrost_device.h| 4 -
> drivers/gpu/drm/panfrost/panfrost_drv.c | 19 +--
> drivers/gpu/drm/panfrost/panfrost_gem.c | 33 +++--
> drivers/gpu/drm/panfrost/panfrost_gem.h | 9 --
> .../gpu/drm/panfrost/panfrost_gem_shrinker.c | 129 --
> drivers/gpu/drm/panfrost/panfrost_job.c | 18 ++-
> 7 files changed, 42 insertions(+), 171 deletions(-)
> delete mode 100644 drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
>
> diff --git a/drivers/gpu/drm/panfrost/Makefile
> b/drivers/gpu/drm/panfrost/Makefile
> index 7da2b3f02ed9..11622e22cf15 100644
> --- a/drivers/gpu/drm/panfrost/Makefile
> +++ b/drivers/gpu/drm/panfrost/Makefile
> @@ -5,7 +5,6 @@ panfrost-y := \
> panfrost_device.o \
> panfrost_devfreq.o \
> panfrost_gem.o \
> - panfrost_gem_shrinker.o \
> panfrost_gpu.o \
> panfrost_job.o \
> panfrost_mmu.o \
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h
> b/drivers/gpu/drm/panfrost/panfrost_device.h
> index 8b25278f34c8..fe04b21fc044 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -115,10 +115,6 @@ struct panfrost_device {
> atomic_t pending;
> } reset;
>
> - struct mutex shrinker_lock;
> - struct list_head shrinker_list;
> - struct shrinker shrinker;
> -
> struct panfrost_devfreq pfdevfreq;
> };
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c
> b/drivers/gpu/drm/panfrost/panfrost_drv.c
> index 94b8e6de34b8..fe78d5c75abf 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_drv.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
> @@ -160,7 +160,6 @@ panfrost_lookup_bos(struct drm_device *dev,
> break;
> }
>
> - atomic_inc(>gpu_usecount);
> job->mappings[i] = mapping;
> }
>
> @@ -392,7 +391,6 @@ static int panfrost_ioctl_madvise(struct drm_device *dev,
> void *data,
> {
> struct panfrost_file_priv *priv = file_priv->driver_priv;
> struct drm_panfrost_madvise *args = data;
> - struct panfrost_device *pfdev = dev->dev_private;
> struct drm_gem_object *gem_obj;
> struct panfrost_gem_object *bo;
> int ret = 0;
> @@ -409,7 +407,6 @@ static int panfrost_ioctl_madvise(struct drm_device *dev,
> void *data,
> if (ret)
> goto out_put_object;
>
> - mutex_lock(>shrinker_lock);
> mutex_lock(>mappings.lock);
> if (args->madv == PANFROST_MADV_DONTNEED) {
> struct panfrost_gem_mapping *first;
> @@ -435,17 +432,8 @@ static int panfrost_ioctl_madvise(struct drm_device
> *dev, void *data,
>
> args->retained = drm_gem_shmem_madvise(>base, args->madv);
>
> - if (args->retained) {
> - if (args->madv == PANFROST_MADV_DONTNEED)
> - list_move_tail(>base.madv_list,
> ->shrinker_list);
> - else if (args->madv == PANFROST_MADV_WILLNEED)
> - list_del_init(>base.madv_list);
> - }
> -
> out_unlock_mappings:
> mutex_unlock(>mappings.lock);
> - mutex_unlock(>shrinker_lock);
> dma_resv_unlock(bo->base.base.resv);
> out_put_object:
> drm_gem_object_put(gem_obj);
> @@ -577,9 +565,6 @@ static int panfrost_probe(struct platform_device *pdev)
> ddev->dev_private = pfdev;
> pfdev->ddev = ddev;
>
> - mutex_init(>shrinker_lock);
> - INIT_LIST_HEAD(>shrinker_list);
> -
> err = panfrost_device_init(pfdev);
> if (err) {
> if (err != -EPROBE_DEFER)
> @@ -601,7 +586,7 @@ static int panfrost_probe(struct platform_device *pdev)
> if (err < 0)
> goto err_out1;
>
> - panfrost_gem_shrinker_init(ddev);
> + drm_gem_shmem_shrinker_register(ddev, "panfrost-shrinker");
>
> return 0;
>
> @@ -619,8 +604,8 @@ static int panfrost_remove(struct platform_device *pdev)
> struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> struct drm_device *ddev = pfdev->ddev;
>
> +
[PATCH v8 7/7] drm/panfrost: Switch to generic memory shrinker
Replace Panfrost's custom memory shrinker with a common drm-shmem
memory shrinker.
Signed-off-by: Dmitry Osipenko
---
drivers/gpu/drm/panfrost/Makefile | 1 -
drivers/gpu/drm/panfrost/panfrost_device.h| 4 -
drivers/gpu/drm/panfrost/panfrost_drv.c | 19 +--
drivers/gpu/drm/panfrost/panfrost_gem.c | 33 +++--
drivers/gpu/drm/panfrost/panfrost_gem.h | 9 --
.../gpu/drm/panfrost/panfrost_gem_shrinker.c | 129 --
drivers/gpu/drm/panfrost/panfrost_job.c | 18 ++-
7 files changed, 42 insertions(+), 171 deletions(-)
delete mode 100644 drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
diff --git a/drivers/gpu/drm/panfrost/Makefile
b/drivers/gpu/drm/panfrost/Makefile
index 7da2b3f02ed9..11622e22cf15 100644
--- a/drivers/gpu/drm/panfrost/Makefile
+++ b/drivers/gpu/drm/panfrost/Makefile
@@ -5,7 +5,6 @@ panfrost-y := \
panfrost_device.o \
panfrost_devfreq.o \
panfrost_gem.o \
- panfrost_gem_shrinker.o \
panfrost_gpu.o \
panfrost_job.o \
panfrost_mmu.o \
diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h
b/drivers/gpu/drm/panfrost/panfrost_device.h
index 8b25278f34c8..fe04b21fc044 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.h
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -115,10 +115,6 @@ struct panfrost_device {
atomic_t pending;
} reset;
- struct mutex shrinker_lock;
- struct list_head shrinker_list;
- struct shrinker shrinker;
-
struct panfrost_devfreq pfdevfreq;
};
diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c
b/drivers/gpu/drm/panfrost/panfrost_drv.c
index 94b8e6de34b8..fe78d5c75abf 100644
--- a/drivers/gpu/drm/panfrost/panfrost_drv.c
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -160,7 +160,6 @@ panfrost_lookup_bos(struct drm_device *dev,
break;
}
- atomic_inc(>gpu_usecount);
job->mappings[i] = mapping;
}
@@ -392,7 +391,6 @@ static int panfrost_ioctl_madvise(struct drm_device *dev,
void *data,
{
struct panfrost_file_priv *priv = file_priv->driver_priv;
struct drm_panfrost_madvise *args = data;
- struct panfrost_device *pfdev = dev->dev_private;
struct drm_gem_object *gem_obj;
struct panfrost_gem_object *bo;
int ret = 0;
@@ -409,7 +407,6 @@ static int panfrost_ioctl_madvise(struct drm_device *dev,
void *data,
if (ret)
goto out_put_object;
- mutex_lock(>shrinker_lock);
mutex_lock(>mappings.lock);
if (args->madv == PANFROST_MADV_DONTNEED) {
struct panfrost_gem_mapping *first;
@@ -435,17 +432,8 @@ static int panfrost_ioctl_madvise(struct drm_device *dev,
void *data,
args->retained = drm_gem_shmem_madvise(>base, args->madv);
- if (args->retained) {
- if (args->madv == PANFROST_MADV_DONTNEED)
- list_move_tail(>base.madv_list,
- >shrinker_list);
- else if (args->madv == PANFROST_MADV_WILLNEED)
- list_del_init(>base.madv_list);
- }
-
out_unlock_mappings:
mutex_unlock(>mappings.lock);
- mutex_unlock(>shrinker_lock);
dma_resv_unlock(bo->base.base.resv);
out_put_object:
drm_gem_object_put(gem_obj);
@@ -577,9 +565,6 @@ static int panfrost_probe(struct platform_device *pdev)
ddev->dev_private = pfdev;
pfdev->ddev = ddev;
- mutex_init(>shrinker_lock);
- INIT_LIST_HEAD(>shrinker_list);
-
err = panfrost_device_init(pfdev);
if (err) {
if (err != -EPROBE_DEFER)
@@ -601,7 +586,7 @@ static int panfrost_probe(struct platform_device *pdev)
if (err < 0)
goto err_out1;
- panfrost_gem_shrinker_init(ddev);
+ drm_gem_shmem_shrinker_register(ddev, "panfrost-shrinker");
return 0;
@@ -619,8 +604,8 @@ static int panfrost_remove(struct platform_device *pdev)
struct panfrost_device *pfdev = platform_get_drvdata(pdev);
struct drm_device *ddev = pfdev->ddev;
+ drm_gem_shmem_shrinker_unregister(ddev);
drm_dev_unregister(ddev);
- panfrost_gem_shrinker_cleanup(ddev);
pm_runtime_get_sync(pfdev->dev);
pm_runtime_disable(pfdev->dev);
diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c
b/drivers/gpu/drm/panfrost/panfrost_gem.c
index 293e799e2fe8..f1436405e3a0 100644
--- a/drivers/gpu/drm/panfrost/panfrost_gem.c
+++ b/drivers/gpu/drm/panfrost/panfrost_gem.c
@@ -19,16 +19,6 @@ static void panfrost_gem_free_object(struct drm_gem_object
*obj)
struct panfrost_gem_object *bo = to_panfrost_bo(obj);
struct panfrost_device *pfdev = obj->dev->dev_private;
- /*
-* Make sure the BO is no longer inserted in the shrinker list before
-* taking care of the destruction itself. If we don't do that we
