On Fri, 28 Nov 2025 19:52:51 +0100 Loïc Molinari <[email protected]> wrote:
> Introduce the 'panfrost.transparent_hugepage' boolean module parameter > (false by default). When the parameter is set to true, a new tmpfs > mountpoint is created and mounted using the 'huge=within_size' > option. It's then used at GEM object creation instead of the default > 'shm_mnt' mountpoint in order to enable Transparent Hugepage (THP) for > the object (without having to rely on a system wide parameter). > > v3: > - use huge tmpfs mountpoint in drm_device > > v4: > - fix builds with CONFIG_TRANSPARENT_HUGEPAGE=n > - clean up mountpoint creation error handling > - print negative error value > > v5: > - use drm_gem_has_huge_tmp() helper > - get rid of CONFIG_TRANSPARENT_HUGEPAGE ifdefs > > v9: > - replace drm_gem_has_huge_tmp() by drm_gem_get_huge_tmp() > > Signed-off-by: Loïc Molinari <[email protected]> > Reviewed-by: Boris Brezillon <[email protected]> > --- > drivers/gpu/drm/panfrost/panfrost_device.c | 3 +++ > drivers/gpu/drm/panfrost/panfrost_drv.c | 6 ++++++ > drivers/gpu/drm/panfrost/panfrost_drv.h | 9 +++++++++ > drivers/gpu/drm/panfrost/panfrost_gem.c | 18 ++++++++++++++++++ > drivers/gpu/drm/panfrost/panfrost_gem.h | 2 ++ > 5 files changed, 38 insertions(+) > create mode 100644 drivers/gpu/drm/panfrost/panfrost_drv.h > > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c > b/drivers/gpu/drm/panfrost/panfrost_device.c > index c61b97af120c..dedc13e56631 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_device.c > +++ b/drivers/gpu/drm/panfrost/panfrost_device.c > @@ -12,6 +12,7 @@ > #include "panfrost_device.h" > #include "panfrost_devfreq.h" > #include "panfrost_features.h" > +#include "panfrost_gem.h" > #include "panfrost_issues.h" > #include "panfrost_gpu.h" > #include "panfrost_job.h" > @@ -267,6 +268,8 @@ int panfrost_device_init(struct panfrost_device *pfdev) > if (err) > goto out_job; > > + panfrost_gem_init(pfdev); > + > return 0; > out_job: > panfrost_jm_fini(pfdev); > diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c > b/drivers/gpu/drm/panfrost/panfrost_drv.c > index 7d8c7c337606..7f59568faa05 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_drv.c > +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c > @@ -858,6 +858,12 @@ static const struct drm_driver panfrost_drm_driver = { > #endif > }; > > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE > +bool panfrost_transparent_hugepage; Same here, if there's no downside to enabling THP support, make it the default. > +module_param_named(transparent_hugepage, panfrost_transparent_hugepage, > bool, 0400); > +MODULE_PARM_DESC(transparent_hugepage, "Use a dedicated tmpfs mount point > with Transparent Hugepage enabled (false = default)"); > +#endif > + > static int panfrost_probe(struct platform_device *pdev) > { > struct panfrost_device *pfdev; > diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.h > b/drivers/gpu/drm/panfrost/panfrost_drv.h > new file mode 100644 > index 000000000000..edeb093eb6da > --- /dev/null > +++ b/drivers/gpu/drm/panfrost/panfrost_drv.h > @@ -0,0 +1,9 @@ > +// SPDX-License-Identifier: GPL-2.0 or MIT > +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ > + > +#ifndef __PANFROST_DRV_H__ > +#define __PANFROST_DRV_H__ > + > +extern bool panfrost_transparent_hugepage; > + > +#endif > diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c > b/drivers/gpu/drm/panfrost/panfrost_gem.c > index 8041b65c6609..c1688a542ec2 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_gem.c > +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c > @@ -1,5 +1,6 @@ > // SPDX-License-Identifier: GPL-2.0 > /* Copyright 2019 Linaro, Ltd, Rob Herring <[email protected]> */ > +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ > > #include <linux/cleanup.h> > #include <linux/err.h> > @@ -10,9 +11,26 @@ > #include <drm/panfrost_drm.h> > #include <drm/drm_print.h> > #include "panfrost_device.h" > +#include "panfrost_drv.h" > #include "panfrost_gem.h" > #include "panfrost_mmu.h" > > +void panfrost_gem_init(struct panfrost_device *pfdev) > +{ > + int err; > + > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && > + !panfrost_transparent_hugepage) > + return; > + > + err = drm_gem_huge_mnt_create(&pfdev->base, "within_size"); > + if (drm_gem_get_huge_mnt(&pfdev->base)) > + drm_info(&pfdev->base, "Using Transparent Hugepage\n"); > + else if (err) > + drm_warn(&pfdev->base, "Can't use Transparent Hugepage (%d)\n", > + err); > +} > + > #ifdef CONFIG_DEBUG_FS > static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev, > struct panfrost_gem_object *bo) > diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h > b/drivers/gpu/drm/panfrost/panfrost_gem.h > index 8de3e76f2717..1a62529ff06f 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_gem.h > +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h > @@ -124,6 +124,8 @@ drm_mm_node_to_panfrost_mapping(struct drm_mm_node *node) > return container_of(node, struct panfrost_gem_mapping, mmnode); > } > > +void panfrost_gem_init(struct panfrost_device *pfdev); > + > struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, > size_t size); > > struct drm_gem_object *
