| Message ID | 20240105184624.508603-15-dmitry.osipenko@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add generic memory shrinker to VirtIO-GPU and Panfrost DRM drivers | expand |
On Fri, 5 Jan 2024 21:46:08 +0300 Dmitry Osipenko <dmitry.osipenko@collabora.com> wrote: > We're going to move away from having implicit get_pages() done by > get_pages_sgt() to ease simplify refcnt handling. Drivers will manage > get/put_pages() by themselves. Add drm_gem_shmem_put_pages(). > > Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> > --- > drivers/gpu/drm/drm_gem_shmem_helper.c | 20 ++++++++++++++++++++ > include/drm/drm_gem_shmem_helper.h | 1 + > 2 files changed, 21 insertions(+) > > diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c > index dc416a4bce1b..f5ed64f78648 100644 > --- a/drivers/gpu/drm/drm_gem_shmem_helper.c > +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c > @@ -218,6 +218,7 @@ static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) > * @shmem: shmem GEM object > * > * This function decreases the use count and puts the backing pages when use drops to zero. > + * Caller must hold GEM's reservation lock. > */ > void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) > { > @@ -228,6 +229,25 @@ void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) > } > EXPORT_SYMBOL_GPL(drm_gem_shmem_put_pages_locked); > > +/* > + * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object > + * @shmem: shmem GEM object > + * > + * This function decreases the use count and puts the backing pages when use drops to zero. > + * It's unlocked version of drm_gem_shmem_put_pages_locked(), caller must not hold > + * GEM's reservation lock. > + */ > +void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) > +{ > + if (refcount_dec_not_one(&shmem->pages_use_count)) > + return; > + > + dma_resv_lock(shmem->base.resv, NULL); > + drm_gem_shmem_put_pages_locked(shmem); > + dma_resv_unlock(shmem->base.resv); > +} > +EXPORT_SYMBOL_GPL(drm_gem_shmem_put_pages); > + > /* > * drm_gem_shmem_get_pages - Increase use count on the backing pages for a shmem GEM object > * @shmem: shmem GEM object > diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h > index 6dedc0739fbc..525480488451 100644 > --- a/include/drm/drm_gem_shmem_helper.h > +++ b/include/drm/drm_gem_shmem_helper.h > @@ -111,6 +111,7 @@ struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t > void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem); > > int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem); > +void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem); > void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem); > int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem); > void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index dc416a4bce1b..f5ed64f78648 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -218,6 +218,7 @@ static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) * @shmem: shmem GEM object * * This function decreases the use count and puts the backing pages when use drops to zero. + * Caller must hold GEM's reservation lock. */ void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) { @@ -228,6 +229,25 @@ void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) } EXPORT_SYMBOL_GPL(drm_gem_shmem_put_pages_locked); +/* + * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object + * @shmem: shmem GEM object + * + * This function decreases the use count and puts the backing pages when use drops to zero. + * It's unlocked version of drm_gem_shmem_put_pages_locked(), caller must not hold + * GEM's reservation lock. + */ +void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) +{ + if (refcount_dec_not_one(&shmem->pages_use_count)) + return; + + dma_resv_lock(shmem->base.resv, NULL); + drm_gem_shmem_put_pages_locked(shmem); + dma_resv_unlock(shmem->base.resv); +} +EXPORT_SYMBOL_GPL(drm_gem_shmem_put_pages); + /* * drm_gem_shmem_get_pages - Increase use count on the backing pages for a shmem GEM object * @shmem: shmem GEM object diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 6dedc0739fbc..525480488451 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -111,6 +111,7 @@ struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem); int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem); +void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem); int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
We're going to move away from having implicit get_pages() done by get_pages_sgt() to ease simplify refcnt handling. Drivers will manage get/put_pages() by themselves. Add drm_gem_shmem_put_pages(). Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 20 ++++++++++++++++++++ include/drm/drm_gem_shmem_helper.h | 1 + 2 files changed, 21 insertions(+)