Thomas Zimmermann
2023-Feb-17 13:19 UTC
[PATCH v10 08/11] drm/shmem-helper: Add memory shrinker
Hi Am 08.01.23 um 22:04 schrieb Dmitry Osipenko:> Introduce common drm-shmem shrinker for DRM drivers. > > To start using drm-shmem shrinker drivers should do the following: > > 1. Implement evict() callback of GEM object where driver should check > whether object is purgeable or evictable using drm-shmem helpers and > perform the shrinking action > > 2. Initialize drm-shmem internals using drmm_gem_shmem_init(drm_device), > which will register drm-shmem shrinker > > 3. Implement madvise IOCTL that will use drm_gem_shmem_madvise()I left commenets beloew, but it's complicated code and a fairly large change. It there any chance of splitting this up in a meaningful way?> > Signed-off-by: Daniel Almeida <daniel.almeida at collabora.com> > Signed-off-by: Dmitry Osipenko <dmitry.osipenko at collabora.com> > --- > drivers/gpu/drm/drm_gem_shmem_helper.c | 460 ++++++++++++++++-- > .../gpu/drm/panfrost/panfrost_gem_shrinker.c | 9 +- > include/drm/drm_device.h | 10 +- > include/drm/drm_gem_shmem_helper.h | 61 ++- > 4 files changed, 490 insertions(+), 50 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c > index a1f2f2158c50..3ab5ec325ddb 100644 > --- a/drivers/gpu/drm/drm_gem_shmem_helper.c > +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c > @@ -20,6 +20,7 @@ > #include <drm/drm_device.h> > #include <drm/drm_drv.h> > #include <drm/drm_gem_shmem_helper.h> > +#include <drm/drm_managed.h> > #include <drm/drm_prime.h> > #include <drm/drm_print.h> > > @@ -128,6 +129,57 @@ struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t > } > EXPORT_SYMBOL_GPL(drm_gem_shmem_create); > > +static void drm_gem_shmem_resv_assert_held(struct drm_gem_shmem_object *shmem) > +{ > + /* > + * Destroying the object is a special case.. drm_gem_shmem_free() > + * calls many things that WARN_ON if the obj lock is not held. But > + * acquiring the obj lock in drm_gem_shmem_free() can cause a locking > + * order inversion between reservation_ww_class_mutex and fs_reclaim. > + * > + * This deadlock is not actually possible, because no one should > + * be already holding the lock when msm_gem_free_object() is called. > + * Unfortunately lockdep is not aware of this detail. So when the > + * refcount drops to zero, we pretend it is already locked. > + */ > + if (kref_read(&shmem->base.refcount)) > + dma_resv_assert_held(shmem->base.resv); > +} > + > +static bool drm_gem_shmem_is_evictable(struct drm_gem_shmem_object *shmem) > +{ > + dma_resv_assert_held(shmem->base.resv); > + > + return (shmem->madv >= 0) && shmem->base.funcs->evict && > + shmem->pages_use_count && !shmem->pages_pin_count && > + !shmem->base.dma_buf && !shmem->base.import_attach && > + shmem->sgt && !shmem->evicted; > +} > + > +static void > +drm_gem_shmem_update_pages_state(struct drm_gem_shmem_object *shmem) > +{ > + struct drm_gem_object *obj = &shmem->base; > + struct drm_gem_shmem *shmem_mm = obj->dev->shmem_mm; > + struct drm_gem_shmem_shrinker *gem_shrinker = &shmem_mm->shrinker; > + > + drm_gem_shmem_resv_assert_held(shmem); > + > + if (!gem_shrinker || obj->import_attach) > + return; > + > + if (shmem->madv < 0) > + drm_gem_lru_remove(&shmem->base); > + else if (drm_gem_shmem_is_evictable(shmem) || drm_gem_shmem_is_purgeable(shmem)) > + drm_gem_lru_move_tail(&gem_shrinker->lru_evictable, &shmem->base); > + else if (shmem->evicted) > + drm_gem_lru_move_tail(&gem_shrinker->lru_evicted, &shmem->base); > + else if (!shmem->pages) > + drm_gem_lru_remove(&shmem->base); > + else > + drm_gem_lru_move_tail(&gem_shrinker->lru_pinned, &shmem->base); > +} > + > /** > * drm_gem_shmem_free - Free resources associated with a shmem GEM object > * @shmem: shmem GEM object to free > @@ -142,7 +194,8 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) > if (obj->import_attach) { > drm_prime_gem_destroy(obj, shmem->sgt); > } else { > - dma_resv_lock(shmem->base.resv, NULL); > + /* take out shmem GEM object from the memory shrinker */ > + drm_gem_shmem_madvise(shmem, -1); > > drm_WARN_ON(obj->dev, shmem->vmap_use_count); > > @@ -152,12 +205,10 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) > sg_free_table(shmem->sgt); > kfree(shmem->sgt); > } > - if (shmem->pages) > + if (shmem->pages_use_count) > drm_gem_shmem_put_pages(shmem); > > drm_WARN_ON(obj->dev, shmem->pages_use_count); > - > - dma_resv_unlock(shmem->base.resv); > } > > drm_gem_object_release(obj); > @@ -165,19 +216,31 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) > } > EXPORT_SYMBOL_GPL(drm_gem_shmem_free); > > -static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) > +static int > +drm_gem_shmem_acquire_pages(struct drm_gem_shmem_object *shmem) > { > struct drm_gem_object *obj = &shmem->base; > struct page **pages; > > - if (shmem->pages_use_count++ > 0) > + dma_resv_assert_held(shmem->base.resv); > + > + if (shmem->madv < 0) { > + drm_WARN_ON(obj->dev, shmem->pages); > + return -ENOMEM; > + } > + > + if (shmem->pages) { > + drm_WARN_ON(obj->dev, !shmem->evicted); > return 0; > + } > + > + if (drm_WARN_ON(obj->dev, !shmem->pages_use_count)) > + return -EINVAL; > > pages = drm_gem_get_pages(obj); > if (IS_ERR(pages)) { > drm_dbg_kms(obj->dev, "Failed to get pages (%ld)\n", > PTR_ERR(pages)); > - shmem->pages_use_count = 0; > return PTR_ERR(pages); > } > > @@ -196,6 +259,58 @@ static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) > return 0; > } > > +static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) > +{ > + int err; > + > + dma_resv_assert_held(shmem->base.resv); > + > + if (shmem->madv < 0) > + return -ENOMEM; > + > + if (shmem->pages_use_count++ > 0) { > + err = drm_gem_shmem_swap_in(shmem); > + if (err) > + goto err_zero_use; > + > + return 0; > + } > + > + err = drm_gem_shmem_acquire_pages(shmem); > + if (err) > + goto err_zero_use; > + > + drm_gem_shmem_update_pages_state(shmem); > + > + return 0; > + > +err_zero_use: > + shmem->pages_use_count = 0; > + > + return err; > +} > + > +static void > +drm_gem_shmem_release_pages(struct drm_gem_shmem_object *shmem) > +{ > + struct drm_gem_object *obj = &shmem->base; > + > + if (!shmem->pages) { > + drm_WARN_ON(obj->dev, !shmem->evicted && shmem->madv >= 0); > + return; > + } > + > +#ifdef CONFIG_X86 > + if (shmem->map_wc) > + set_pages_array_wb(shmem->pages, obj->size >> PAGE_SHIFT); > +#endif > + > + drm_gem_put_pages(obj, shmem->pages, > + shmem->pages_mark_dirty_on_put, > + shmem->pages_mark_accessed_on_put); > + shmem->pages = NULL; > +} > + > /* > * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object > * @shmem: shmem GEM object > @@ -206,7 +321,7 @@ void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) > { > struct drm_gem_object *obj = &shmem->base; > > - dma_resv_assert_held(shmem->base.resv); > + drm_gem_shmem_resv_assert_held(shmem); > > if (drm_WARN_ON_ONCE(obj->dev, !shmem->pages_use_count)) > return; > @@ -214,15 +329,9 @@ void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) > if (--shmem->pages_use_count > 0) > return; > > -#ifdef CONFIG_X86 > - if (shmem->map_wc) > - set_pages_array_wb(shmem->pages, obj->size >> PAGE_SHIFT); > -#endif > + drm_gem_shmem_release_pages(shmem); > > - drm_gem_put_pages(obj, shmem->pages, > - shmem->pages_mark_dirty_on_put, > - shmem->pages_mark_accessed_on_put); > - shmem->pages = NULL; > + drm_gem_shmem_update_pages_state(shmem); > } > EXPORT_SYMBOL(drm_gem_shmem_put_pages); > > @@ -239,12 +348,17 @@ EXPORT_SYMBOL(drm_gem_shmem_put_pages); > int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem) > { > struct drm_gem_object *obj = &shmem->base; > + int ret; > > dma_resv_assert_held(shmem->base.resv); > > drm_WARN_ON(obj->dev, obj->import_attach); > > - return drm_gem_shmem_get_pages(shmem); > + ret = drm_gem_shmem_get_pages(shmem); > + if (!ret) > + shmem->pages_pin_count++; > + > + return ret; > } > EXPORT_SYMBOL(drm_gem_shmem_pin); > > @@ -263,7 +377,12 @@ void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem) > > drm_WARN_ON(obj->dev, obj->import_attach); > > + if (drm_WARN_ON_ONCE(obj->dev, !shmem->pages_pin_count)) > + return; > + > drm_gem_shmem_put_pages(shmem); > + > + shmem->pages_pin_count--; > } > EXPORT_SYMBOL(drm_gem_shmem_unpin); > > @@ -306,7 +425,7 @@ int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, > return 0; > } > > - ret = drm_gem_shmem_get_pages(shmem); > + ret = drm_gem_shmem_pin(shmem); > if (ret) > goto err_zero_use; > > @@ -329,7 +448,7 @@ int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, > > err_put_pages: > if (!obj->import_attach) > - drm_gem_shmem_put_pages(shmem); > + drm_gem_shmem_unpin(shmem); > err_zero_use: > shmem->vmap_use_count = 0; > > @@ -366,7 +485,7 @@ void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, > return; > > vunmap(shmem->vaddr); > - drm_gem_shmem_put_pages(shmem); > + drm_gem_shmem_unpin(shmem); > } > > shmem->vaddr = NULL; > @@ -403,48 +522,84 @@ drm_gem_shmem_create_with_handle(struct drm_file *file_priv, > */ > int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv) > { > - dma_resv_assert_held(shmem->base.resv); > + drm_gem_shmem_resv_assert_held(shmem); > > if (shmem->madv >= 0) > shmem->madv = madv; > > madv = shmem->madv; > > + drm_gem_shmem_update_pages_state(shmem); > + > return (madv >= 0); > } > EXPORT_SYMBOL(drm_gem_shmem_madvise); > > -void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem) > +/** > + * drm_gem_shmem_swap_in() - Moves shmem GEM back to memory and enables > + * hardware access to the memory.Do we have a better name than _swap_in()? I suggest drm_gem_shmem_unevict(), which suggest that it's the inverse to _evict().> + * @shmem: shmem GEM object > + * > + * This function moves shmem GEM back to memory if it was previously evicted > + * by the memory shrinker. The GEM is ready to use on success. > + * > + * Returns: > + * 0 on success or a negative error code on failure. > + */ > +int drm_gem_shmem_swap_in(struct drm_gem_shmem_object *shmem) > { > struct drm_gem_object *obj = &shmem->base; > - struct drm_device *dev = obj->dev; > + struct sg_table *sgt; > + int err; > > dma_resv_assert_held(shmem->base.resv); > > - drm_WARN_ON(obj->dev, !drm_gem_shmem_is_purgeable(shmem)); > + if (shmem->evicted) { > + err = drm_gem_shmem_acquire_pages(shmem); > + if (err) > + return err; > + > + sgt = drm_gem_shmem_get_sg_table(shmem); > + if (IS_ERR(sgt)) > + return PTR_ERR(sgt); > + > + err = dma_map_sgtable(obj->dev->dev, sgt, > + DMA_BIDIRECTIONAL, 0); > + if (err) { > + sg_free_table(sgt); > + kfree(sgt); > + return err; > + } > > - dma_unmap_sgtable(dev->dev, shmem->sgt, DMA_BIDIRECTIONAL, 0); > - sg_free_table(shmem->sgt); > - kfree(shmem->sgt); > - shmem->sgt = NULL; > + shmem->sgt = sgt; > + shmem->evicted = false; > > - drm_gem_shmem_put_pages(shmem); > + drm_gem_shmem_update_pages_state(shmem); > + } > > - shmem->madv = -1; > + if (!shmem->pages) > + return -ENOMEM; > > - drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping); > - drm_gem_free_mmap_offset(obj); > + return 0; > +} > +EXPORT_SYMBOL_GPL(drm_gem_shmem_swap_in); > > - /* Our goal here is to return as much of the memory as > - * is possible back to the system as we are called from OOM. > - * To do this we must instruct the shmfs to drop all of its > - * backing pages, *now*. > - */ > - shmem_truncate_range(file_inode(obj->filp), 0, (loff_t)-1); > +static void drm_gem_shmem_unpin_pages(struct drm_gem_shmem_object *shmem) > +{ > + struct drm_gem_object *obj = &shmem->base; > + struct drm_device *dev = obj->dev; > > - invalidate_mapping_pages(file_inode(obj->filp)->i_mapping, 0, (loff_t)-1); > + if (shmem->evicted) > + return; > + > + dma_unmap_sgtable(dev->dev, shmem->sgt, DMA_BIDIRECTIONAL, 0); > + drm_gem_shmem_release_pages(shmem); > + drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping); > + > + sg_free_table(shmem->sgt); > + kfree(shmem->sgt); > + shmem->sgt = NULL; > } > -EXPORT_SYMBOL(drm_gem_shmem_purge); > > /** > * drm_gem_shmem_dumb_create - Create a dumb shmem buffer object > @@ -495,22 +650,33 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) > vm_fault_t ret; > struct page *page; > pgoff_t page_offset; > + bool pages_unpinned; > + int err; > > /* We don't use vmf->pgoff since that has the fake offset */ > page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT; > > dma_resv_lock(shmem->base.resv, NULL); > > - if (page_offset >= num_pages || > - drm_WARN_ON_ONCE(obj->dev, !shmem->pages) || > - shmem->madv < 0) { > + /* Sanity-check that we have the pages pointer when it should present */ > + pages_unpinned = (shmem->evicted || shmem->madv < 0 || !shmem->pages_use_count); > + drm_WARN_ON_ONCE(obj->dev, !shmem->pages ^ pages_unpinned); > + > + if (page_offset >= num_pages || (!shmem->pages && !shmem->evicted)) { > ret = VM_FAULT_SIGBUS; > } else { > + err = drm_gem_shmem_swap_in(shmem); > + if (err) { > + ret = VM_FAULT_OOM; > + goto unlock; > + } > + > page = shmem->pages[page_offset]; > > ret = vmf_insert_pfn(vma, vmf->address, page_to_pfn(page)); > } > > +unlock: > dma_resv_unlock(shmem->base.resv); > > return ret; > @@ -533,6 +699,7 @@ static void drm_gem_shmem_vm_open(struct vm_area_struct *vma) > if (!drm_WARN_ON_ONCE(obj->dev, !shmem->pages_use_count)) > shmem->pages_use_count++; > > + drm_gem_shmem_update_pages_state(shmem); > dma_resv_unlock(shmem->base.resv); > > drm_gem_vm_open(vma); > @@ -615,7 +782,9 @@ void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem, > drm_printf_indent(p, indent, "vmap_use_count=%u\n", > shmem->vmap_use_count); > > + drm_printf_indent(p, indent, "evicted=%d\n", shmem->evicted); > drm_printf_indent(p, indent, "vaddr=%p\n", shmem->vaddr); > + drm_printf_indent(p, indent, "madv=%d\n", shmem->madv); > } > EXPORT_SYMBOL(drm_gem_shmem_print_info); > > @@ -688,6 +857,8 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem) > > shmem->sgt = sgt; > > + drm_gem_shmem_update_pages_state(shmem); > + > dma_resv_unlock(shmem->base.resv); > > return sgt; > @@ -738,6 +909,209 @@ drm_gem_shmem_prime_import_sg_table(struct drm_device *dev, > } > EXPORT_SYMBOL_GPL(drm_gem_shmem_prime_import_sg_table); > > +static struct drm_gem_shmem_shrinker * > +to_drm_shrinker(struct shrinker *shrinker)to_drm_gem_shmem_shrinker()> +{ > + return container_of(shrinker, struct drm_gem_shmem_shrinker, base); > +} > + > +static unsigned long > +drm_gem_shmem_shrinker_count_objects(struct shrinker *shrinker, > + struct shrink_control *sc) > +{ > + struct drm_gem_shmem_shrinker *gem_shrinker = to_drm_shrinker(shrinker); > + unsigned long count = gem_shrinker->lru_evictable.count; > + > + if (count >= SHRINK_EMPTY) > + return SHRINK_EMPTY - 1; > + > + return count ?: SHRINK_EMPTY; > +} > + > +void drm_gem_shmem_evict(struct drm_gem_shmem_object *shmem) > +{ > + struct drm_gem_object *obj = &shmem->base; > + > + drm_WARN_ON(obj->dev, !drm_gem_shmem_is_evictable(shmem)); > + drm_WARN_ON(obj->dev, shmem->evicted); > + > + drm_gem_shmem_unpin_pages(shmem); > + > + shmem->evicted = true; > + drm_gem_shmem_update_pages_state(shmem); > +} > +EXPORT_SYMBOL_GPL(drm_gem_shmem_evict); > + > +void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem) > +{ > + struct drm_gem_object *obj = &shmem->base; > + > + drm_WARN_ON(obj->dev, !drm_gem_shmem_is_purgeable(shmem)); > + > + drm_gem_shmem_unpin_pages(shmem); > + drm_gem_free_mmap_offset(obj); > + > + /* Our goal here is to return as much of the memory as > + * is possible back to the system as we are called from OOM. > + * To do this we must instruct the shmfs to drop all of its > + * backing pages, *now*. > + */ > + shmem_truncate_range(file_inode(obj->filp), 0, (loff_t)-1); > + > + invalidate_mapping_pages(file_inode(obj->filp)->i_mapping, 0, (loff_t)-1); > + > + shmem->madv = -1; > + shmem->evicted = false; > + drm_gem_shmem_update_pages_state(shmem); > +} > +EXPORT_SYMBOL_GPL(drm_gem_shmem_purge); > + > +static bool drm_gem_is_busy(struct drm_gem_object *obj) > +{ > + return !dma_resv_test_signaled(obj->resv, DMA_RESV_USAGE_READ); > +}This is a generic GEM function. But do we need it?> + > +static bool drm_gem_shmem_shrinker_evict(struct drm_gem_object *obj) > +{ > + struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); > + > + if (!drm_gem_shmem_is_evictable(shmem) || > + get_nr_swap_pages() < obj->size >> PAGE_SHIFT || > + drm_gem_is_busy(obj))Because here and below, we call drm_gem_is_busy(). Could we test dma_resv_test_signaled() directly in drm_gem_shmem_evict() once and for all?> + return false; > + > + return drm_gem_object_evict(obj);I complaint about the use of booleans before. Here is should be int ret = _evcit(); if (ret) return false; return true and the shrink callback for drm_gem_lru_scan() should be changed to use errno codes as well. That's for a later patchset.> +} > + > +static bool drm_gem_shmem_shrinker_purge(struct drm_gem_object *obj) > +{ > + struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); > + > + if (!drm_gem_shmem_is_purgeable(shmem) || > + drm_gem_is_busy(obj)) > + return false; > + > + return drm_gem_object_evict(obj); > +} > + > +static unsigned long > +drm_gem_shmem_shrinker_scan_objects(struct shrinker *shrinker, > + struct shrink_control *sc) > +{ > + struct drm_gem_shmem_shrinker *gem_shrinker = to_drm_shrinker(shrinker); > + unsigned long nr_to_scan = sc->nr_to_scan; > + unsigned long remaining = 0; > + unsigned long freed = 0; > + > + /* purge as many objects as we can */ > + freed += drm_gem_lru_scan(&gem_shrinker->lru_evictable, > + nr_to_scan, &remaining, > + drm_gem_shmem_shrinker_purge); > + > + /* evict as many objects as we can */ > + if (freed < nr_to_scan) > + freed += drm_gem_lru_scan(&gem_shrinker->lru_evictable, > + nr_to_scan - freed, &remaining, > + drm_gem_shmem_shrinker_evict); > + > + return (freed > 0 && remaining > 0) ? freed : SHRINK_STOP; > +} > + > +static int drm_gem_shmem_shrinker_init(struct drm_gem_shmem *shmem_mm, > + const char *shrinker_name) > +{ > + struct drm_gem_shmem_shrinker *gem_shrinker = &shmem_mm->shrinker; > + int err; > + > + gem_shrinker->base.count_objects = drm_gem_shmem_shrinker_count_objects; > + gem_shrinker->base.scan_objects = drm_gem_shmem_shrinker_scan_objects; > + gem_shrinker->base.seeks = DEFAULT_SEEKS; > + > + mutex_init(&gem_shrinker->lock); > + drm_gem_lru_init(&gem_shrinker->lru_evictable, &gem_shrinker->lock); > + drm_gem_lru_init(&gem_shrinker->lru_evicted, &gem_shrinker->lock); > + drm_gem_lru_init(&gem_shrinker->lru_pinned, &gem_shrinker->lock); > + > + err = register_shrinker(&gem_shrinker->base, shrinker_name); > + if (err) { > + mutex_destroy(&gem_shrinker->lock); > + return err; > + } > + > + return 0; > +} > + > +static void drm_gem_shmem_shrinker_release(struct drm_device *dev, > + struct drm_gem_shmem *shmem_mm) > +{ > + struct drm_gem_shmem_shrinker *gem_shrinker = &shmem_mm->shrinker; > + > + unregister_shrinker(&gem_shrinker->base); > + drm_WARN_ON(dev, !list_empty(&gem_shrinker->lru_evictable.list)); > + drm_WARN_ON(dev, !list_empty(&gem_shrinker->lru_evicted.list)); > + drm_WARN_ON(dev, !list_empty(&gem_shrinker->lru_pinned.list)); > + mutex_destroy(&gem_shrinker->lock); > +} > + > +static int drm_gem_shmem_init(struct drm_device *dev) > +{ > + int err; > + > + if (WARN_ON(dev->shmem_mm))drm_WARN_ON()> + return -EBUSY; > + > + dev->shmem_mm = kzalloc(sizeof(*dev->shmem_mm), GFP_KERNEL); > + if (!dev->shmem_mm) > + return -ENOMEM; > + > + err = drm_gem_shmem_shrinker_init(dev->shmem_mm, dev->unique); > + if (err) > + goto free_gem_shmem; > + > + return 0; > + > +free_gem_shmem: > + kfree(dev->shmem_mm); > + dev->shmem_mm = NULL; > + > + return err; > +} > + > +static void drm_gem_shmem_release(struct drm_device *dev, void *ptr) > +{ > + struct drm_gem_shmem *shmem_mm = dev->shmem_mm; > + > + drm_gem_shmem_shrinker_release(dev, shmem_mm); > + dev->shmem_mm = NULL; > + kfree(shmem_mm); > +} > + > +/** > + * drmm_gem_shmem_init() - Initialize drm-shmem internals > + * @dev: DRM device > + * > + * Cleanup is automatically managed as part of DRM device releasing. > + * Calling this function multiple times will result in a error. > + * > + * Returns: > + * 0 on success or a negative error code on failure. > + */ > +int drmm_gem_shmem_init(struct drm_device *dev) > +{ > + int err; > + > + err = drm_gem_shmem_init(dev); > + if (err) > + return err; > + > + err = drmm_add_action_or_reset(dev, drm_gem_shmem_release, NULL); > + if (err) > + return err; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(drmm_gem_shmem_init); > + > MODULE_DESCRIPTION("DRM SHMEM memory-management helpers"); > MODULE_IMPORT_NS(DMA_BUF); > MODULE_LICENSE("GPL v2"); > diff --git a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c > index 6a71a2555f85..865a989d67c8 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c > +++ b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c > @@ -15,6 +15,13 @@ > #include "panfrost_gem.h" > #include "panfrost_mmu.h" > > +static bool panfrost_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem) > +{ > + return (shmem->madv > 0) && > + !shmem->pages_pin_count && shmem->sgt && > + !shmem->base.dma_buf && !shmem->base.import_attach; > +} > + > static unsigned long > panfrost_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc) > { > @@ -27,7 +34,7 @@ panfrost_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc > return 0; > > list_for_each_entry(shmem, &pfdev->shrinker_list, madv_list) { > - if (drm_gem_shmem_is_purgeable(shmem)) > + if (panfrost_gem_shmem_is_purgeable(shmem)) > count += shmem->base.size >> PAGE_SHIFT; > } > > diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h > index a68c6a312b46..8acd455fc156 100644 > --- a/include/drm/drm_device.h > +++ b/include/drm/drm_device.h > @@ -16,6 +16,7 @@ struct drm_vblank_crtc; > struct drm_vma_offset_manager; > struct drm_vram_mm; > struct drm_fb_helper; > +struct drm_gem_shmem_shrinker; > > struct inode; > > @@ -277,8 +278,13 @@ struct drm_device { > /** @vma_offset_manager: GEM information */ > struct drm_vma_offset_manager *vma_offset_manager; > > - /** @vram_mm: VRAM MM memory manager */ > - struct drm_vram_mm *vram_mm; > + union { > + /** @vram_mm: VRAM MM memory manager */ > + struct drm_vram_mm *vram_mm; > + > + /** @shmem_mm: SHMEM GEM memory manager */ > + struct drm_gem_shmem *shmem_mm; > + }; > > /** > * @switch_power_state: > diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h > index 20ddcd799df9..c264caf6c83b 100644 > --- a/include/drm/drm_gem_shmem_helper.h > +++ b/include/drm/drm_gem_shmem_helper.h > @@ -6,6 +6,7 @@ > #include <linux/fs.h> > #include <linux/mm.h> > #include <linux/mutex.h> > +#include <linux/shrinker.h> > > #include <drm/drm_file.h> > #include <drm/drm_gem.h> > @@ -15,6 +16,7 @@ > struct dma_buf_attachment; > struct drm_mode_create_dumb; > struct drm_printer; > +struct drm_device;Alphabetically, please.> struct sg_table; > > /** > @@ -39,12 +41,21 @@ struct drm_gem_shmem_object { > */ > unsigned int pages_use_count; > > + /** > + * @pages_pin_count: > + * > + * Reference count on the pinned pages table. > + * The pages allowed to be evicted by memory shrinker > + * only when the count is zero. > + */ > + unsigned int pages_pin_count; > + > /** > * @madv: State for madvise > * > * 0 is active/inuse. > + * 1 is not-needed/can-be-purged > * A negative value is the object is purged. > - * Positive values are driver specific and not used by the helpers. > */ > int madv; > > @@ -91,6 +102,12 @@ struct drm_gem_shmem_object { > * @map_wc: map object write-combined (instead of using shmem defaults). > */ > bool map_wc : 1; > + > + /** > + * @evicted: True if shmem pages are evicted by the memory shrinker. > + * Used internally by memory shrinker. > + */ > + bool evicted : 1; > }; > > #define to_drm_gem_shmem_obj(obj) \ > @@ -112,11 +129,17 @@ int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv); > > static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem) > { > - return (shmem->madv > 0) && > - !shmem->vmap_use_count && shmem->sgt && > - !shmem->base.dma_buf && !shmem->base.import_attach; > + dma_resv_assert_held(shmem->base.resv); > + > + return (shmem->madv > 0) && shmem->base.funcs->evict && > + shmem->pages_use_count && !shmem->pages_pin_count && > + !shmem->base.dma_buf && !shmem->base.import_attach && > + (shmem->sgt || shmem->evicted); > } > > +int drm_gem_shmem_swap_in(struct drm_gem_shmem_object *shmem); > + > +void drm_gem_shmem_evict(struct drm_gem_shmem_object *shmem); > void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem); > > struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem); > @@ -260,6 +283,36 @@ static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct v > return drm_gem_shmem_mmap(shmem, vma); > } > > +/** > + * struct drm_gem_shmem_shrinker - Memory shrinker of GEM shmem memory manager > + */ > +struct drm_gem_shmem_shrinker { > + /** @base: Shrinker for purging shmem GEM objects */ > + struct shrinker base; > + > + /** @lock: Protects @lru_* */ > + struct mutex lock; > + > + /** @lru_pinned: List of pinned shmem GEM objects */ > + struct drm_gem_lru lru_pinned; > + > + /** @lru_evictable: List of shmem GEM objects to be evicted */ > + struct drm_gem_lru lru_evictable; > + > + /** @lru_evicted: List of evicted shmem GEM objects */ > + struct drm_gem_lru lru_evicted; > +}; > + > +/** > + * struct drm_gem_shmem - GEM shmem memory manager > + */ > +struct drm_gem_shmem { > + /** @shrinker: GEM shmem shrinker */ > + struct drm_gem_shmem_shrinker shrinker; > +}; > + > +int drmm_gem_shmem_init(struct drm_device *dev); > + > /* > * Driver ops > */-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 N?rnberg, Germany (HRB 36809, AG N?rnberg) Gesch?ftsf?hrer: Ivo Totev -------------- next part -------------- A non-text attachment was scrubbed... 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