From patchwork Sun Sep 3 17:07:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Osipenko X-Patchwork-Id: 13373303 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ABC71C83F2D for ; Sun, 3 Sep 2023 17:09:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 75D3710E117; Sun, 3 Sep 2023 17:09:16 +0000 (UTC) Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by gabe.freedesktop.org (Postfix) with ESMTPS id B331910E110 for ; Sun, 3 Sep 2023 17:09:00 +0000 (UTC) Received: from workpc.. (109-252-153-31.dynamic.spd-mgts.ru [109.252.153.31]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dmitry.osipenko) by madras.collabora.co.uk (Postfix) with ESMTPSA id 0186E66072DE; Sun, 3 Sep 2023 18:08:57 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1693760939; bh=u2d0CW59oyRwVxHtpQuBYqf56+g4KltySw9Q+ePXjw4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Box75CBzyoUI6TRRT3DH/ZEz6GOb2clBfQxDv+J9RBUIXPdHSXUocyUR6k7QBhkGC z8duZaW+HcVBiSubv2Hl/10JRUiGUjJ1hEOlTPs6HXzYk4eUWHMG3I9WC2Ju+89OGv gnhNqykjamTpfGNaA0CfDPBCGC12pZnJ81h/U9sXJaCxuGGsmYHGo8Rr2TRxX8fP7o EtfvtTt6L2eelbXG1Qbwee9VQ2tUoLAjogZjM6MTjFL3SRQWkKerKcOQRDNJm0z1RR Wr1ZS7WSLFM8SuT4yaR5mVfFXFCEZ6JjAi5Kcwa2vlPHbZokP1HC/u0yOYnJkK7cXt tl8ykktkp4MFA== From: Dmitry Osipenko To: David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , =?utf-8?q?Christian_K=C3=B6nig?= , Qiang Yu , Steven Price , Boris Brezillon , Emma Anholt , Melissa Wen Subject: [PATCH v16 15/20] drm/shmem-helper: Add memory shrinker Date: Sun, 3 Sep 2023 20:07:31 +0300 Message-ID: <20230903170736.513347-16-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230903170736.513347-1-dmitry.osipenko@collabora.com> References: <20230903170736.513347-1-dmitry.osipenko@collabora.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kernel@collabora.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" 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() Signed-off-by: Daniel Almeida Signed-off-by: Dmitry Osipenko --- drivers/gpu/drm/drm_gem_shmem_helper.c | 442 ++++++++++++++++-- .../gpu/drm/panfrost/panfrost_gem_shrinker.c | 9 +- include/drm/drm_device.h | 10 +- include/drm/drm_gem_shmem_helper.h | 71 ++- 4 files changed, 494 insertions(+), 38 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 4633a418faba..a0a6c7e505c8 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -88,8 +89,6 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private) if (ret) goto err_release; - INIT_LIST_HEAD(&shmem->madv_list); - if (!private) { /* * Our buffers are kept pinned, so allocating them @@ -128,6 +127,62 @@ struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t } EXPORT_SYMBOL_GPL(drm_gem_shmem_create); +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 && + refcount_read(&shmem->pages_use_count) && + !refcount_read(&shmem->pages_pin_count) && + !shmem->base.dma_buf && !shmem->base.import_attach && + shmem->sgt && !shmem->evicted; +} + +static void +drm_gem_shmem_update_pages_state_locked(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 *shmem_shrinker = &shmem_mm->shrinker; + + dma_resv_assert_held(shmem->base.resv); + + if (!shmem_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(&shmem_shrinker->lru_evictable, &shmem->base); + else if (shmem->evicted) + drm_gem_lru_move_tail(&shmem_shrinker->lru_evicted, &shmem->base); + else if (!shmem->pages) + drm_gem_lru_remove(&shmem->base); + else + drm_gem_lru_move_tail(&shmem_shrinker->lru_pinned, &shmem->base); +} + +static void +drm_gem_shmem_do_release_pages_locked(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_free - Free resources associated with a shmem GEM object * @shmem: shmem GEM object to free @@ -142,8 +197,6 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) if (obj->import_attach) { drm_prime_gem_destroy(obj, shmem->sgt); } else if (!shmem->imported_sgt) { - dma_resv_lock(shmem->base.resv, NULL); - drm_WARN_ON(obj->dev, refcount_read(&shmem->vmap_use_count)); if (shmem->sgt) { @@ -152,14 +205,27 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) sg_free_table(shmem->sgt); kfree(shmem->sgt); } - if (refcount_read(&shmem->pages_use_count)) { - drm_gem_shmem_put_pages_locked(shmem); - drm_WARN_ON(obj->dev, !shmem->got_pages_sgt); + + /* + * 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_release_pages_locked() 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 drm_gem_shmem_free() is called. + * Unfortunately lockdep is not aware of this detail. So when the + * refcount drops to zero, don't touch the reservation lock. + */ + if (shmem->got_pages_sgt && + refcount_dec_and_test(&shmem->pages_use_count)) { + drm_gem_shmem_do_release_pages_locked(shmem); + shmem->got_pages_sgt = false; } drm_WARN_ON(obj->dev, refcount_read(&shmem->pages_use_count)); - - dma_resv_unlock(shmem->base.resv); + drm_WARN_ON(obj->dev, shmem->got_pages_sgt); } drm_gem_object_release(obj); @@ -167,15 +233,26 @@ 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_locked(struct drm_gem_shmem_object *shmem) +static int +drm_gem_shmem_acquire_pages(struct drm_gem_shmem_object *shmem, bool init) { struct drm_gem_object *obj = &shmem->base; struct page **pages; dma_resv_assert_held(shmem->base.resv); - if (refcount_inc_not_zero(&shmem->pages_use_count)) + 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, !(init ^ refcount_read(&shmem->pages_use_count)))) + return -EINVAL; pages = drm_gem_get_pages(obj); if (IS_ERR(pages)) { @@ -196,8 +273,36 @@ static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) shmem->pages = pages; + return 0; +} + +static void +drm_gem_shmem_release_pages_locked(struct drm_gem_shmem_object *shmem) +{ + dma_resv_assert_held(shmem->base.resv); + drm_gem_shmem_do_release_pages_locked(shmem); +} + +static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) +{ + int err; + + dma_resv_assert_held(shmem->base.resv); + + if (shmem->madv < 0) + return -ENOMEM; + + if (refcount_inc_not_zero(&shmem->pages_use_count)) + return 0; + + err = drm_gem_shmem_acquire_pages(shmem, true); + if (err) + return err; + refcount_set(&shmem->pages_use_count, 1); + drm_gem_shmem_update_pages_state_locked(shmem); + return 0; } @@ -209,20 +314,11 @@ static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) */ void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) { - struct drm_gem_object *obj = &shmem->base; - dma_resv_assert_held(shmem->base.resv); if (refcount_dec_and_test(&shmem->pages_use_count)) { -#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_release_pages_locked(shmem); + drm_gem_shmem_update_pages_state_locked(shmem); } } EXPORT_SYMBOL_GPL(drm_gem_shmem_put_pages_locked); @@ -251,8 +347,15 @@ static int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem) return 0; ret = drm_gem_shmem_get_pages_locked(shmem); - if (!ret) + if (!ret) { + ret = drm_gem_shmem_swapin_locked(shmem); + if (ret) { + drm_gem_shmem_put_pages_locked(shmem); + return ret; + } + refcount_set(&shmem->pages_pin_count, 1); + } return ret; } @@ -448,29 +551,54 @@ int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv) madv = shmem->madv; + drm_gem_shmem_update_pages_state_locked(shmem); + return (madv >= 0); } EXPORT_SYMBOL_GPL(drm_gem_shmem_madvise_locked); -void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) +int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv) +{ + struct drm_gem_object *obj = &shmem->base; + int ret; + + ret = dma_resv_lock_interruptible(obj->resv, NULL); + if (ret) + return ret; + + ret = drm_gem_shmem_madvise_locked(shmem, madv); + dma_resv_unlock(obj->resv); + + return ret; +} +EXPORT_SYMBOL_GPL(drm_gem_shmem_madvise); + +static void drm_gem_shmem_unpin_pages_locked(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; struct drm_device *dev = obj->dev; dma_resv_assert_held(shmem->base.resv); - drm_WARN_ON(obj->dev, !drm_gem_shmem_is_purgeable(shmem)); + if (shmem->evicted) + return; dma_unmap_sgtable(dev->dev, shmem->sgt, DMA_BIDIRECTIONAL, 0); + drm_gem_shmem_release_pages_locked(shmem); + drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping); + sg_free_table(shmem->sgt); kfree(shmem->sgt); shmem->sgt = NULL; +} - drm_gem_shmem_put_pages_locked(shmem); +void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) +{ + struct drm_gem_object *obj = &shmem->base; - shmem->madv = -1; + drm_WARN_ON(obj->dev, !drm_gem_shmem_is_purgeable(shmem)); - drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping); + drm_gem_shmem_unpin_pages_locked(shmem); drm_gem_free_mmap_offset(obj); /* Our goal here is to return as much of the memory as @@ -481,9 +609,59 @@ void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem) 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_locked(shmem); } EXPORT_SYMBOL_GPL(drm_gem_shmem_purge_locked); +/** + * drm_gem_shmem_swapin_locked() - Moves shmem GEM back to memory and enables + * hardware access to the memory. + * @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_swapin_locked(struct drm_gem_shmem_object *shmem) +{ + struct drm_gem_object *obj = &shmem->base; + struct sg_table *sgt; + int err; + + dma_resv_assert_held(shmem->base.resv); + + if (shmem->evicted) { + err = drm_gem_shmem_acquire_pages(shmem, false); + 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; + } + + shmem->sgt = sgt; + shmem->evicted = false; + + drm_gem_shmem_update_pages_state_locked(shmem); + } + + return 0; +} +EXPORT_SYMBOL_GPL(drm_gem_shmem_swapin_locked); + /** * drm_gem_shmem_dumb_create - Create a dumb shmem buffer object * @file: DRM file structure to create the dumb buffer for @@ -530,22 +708,34 @@ 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 || + !refcount_read(&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_swapin_locked(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; @@ -568,6 +758,7 @@ static void drm_gem_shmem_vm_open(struct vm_area_struct *vma) drm_WARN_ON_ONCE(obj->dev, !refcount_inc_not_zero(&shmem->pages_use_count)); + drm_gem_shmem_update_pages_state_locked(shmem); dma_resv_unlock(shmem->base.resv); drm_gem_vm_open(vma); @@ -653,7 +844,9 @@ void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem, drm_printf_indent(p, indent, "pages_pin_count=%u\n", refcount_read(&shmem->pages_pin_count)); drm_printf_indent(p, indent, "pages_use_count=%u\n", refcount_read(&shmem->pages_use_count)); drm_printf_indent(p, indent, "vmap_use_count=%u\n", refcount_read(&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_GPL(drm_gem_shmem_print_info); @@ -715,6 +908,8 @@ static struct sg_table *drm_gem_shmem_get_pages_sgt_locked(struct drm_gem_shmem_ shmem->sgt = sgt; + drm_gem_shmem_update_pages_state_locked(shmem); + return sgt; err_free_sgt: @@ -802,6 +997,191 @@ 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_gem_shmem_shrinker(struct shrinker *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 *shmem_shrinker = + to_drm_gem_shmem_shrinker(shrinker); + unsigned long count = shmem_shrinker->lru_evictable.count; + + if (count >= SHRINK_EMPTY) + return SHRINK_EMPTY - 1; + + return count ?: SHRINK_EMPTY; +} + +void drm_gem_shmem_evict_locked(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_locked(shmem); + + shmem->evicted = true; + drm_gem_shmem_update_pages_state_locked(shmem); +} +EXPORT_SYMBOL_GPL(drm_gem_shmem_evict_locked); + +static bool drm_gem_shmem_shrinker_evict_locked(struct drm_gem_object *obj) +{ + struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); + int err; + + if (!drm_gem_shmem_is_evictable(shmem) || + get_nr_swap_pages() < obj->size >> PAGE_SHIFT) + return false; + + err = drm_gem_evict_locked(obj); + if (err) + return false; + + return true; +} + +static bool drm_gem_shmem_shrinker_purge_locked(struct drm_gem_object *obj) +{ + struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); + int err; + + if (!drm_gem_shmem_is_purgeable(shmem)) + return false; + + err = drm_gem_evict_locked(obj); + if (err) + return false; + + return true; +} + +static unsigned long +drm_gem_shmem_shrinker_scan_objects(struct shrinker *shrinker, + struct shrink_control *sc) +{ + struct drm_gem_shmem_shrinker *shmem_shrinker; + unsigned long nr_to_scan = sc->nr_to_scan; + unsigned long remaining = 0; + unsigned long freed = 0; + + shmem_shrinker = to_drm_gem_shmem_shrinker(shrinker); + + /* purge as many objects as we can */ + freed += drm_gem_lru_scan(&shmem_shrinker->lru_evictable, + nr_to_scan, &remaining, + drm_gem_shmem_shrinker_purge_locked); + + /* evict as many objects as we can */ + if (freed < nr_to_scan) + freed += drm_gem_lru_scan(&shmem_shrinker->lru_evictable, + nr_to_scan - freed, &remaining, + drm_gem_shmem_shrinker_evict_locked); + + 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 *shmem_shrinker = &shmem_mm->shrinker; + int err; + + shmem_shrinker->base.count_objects = drm_gem_shmem_shrinker_count_objects; + shmem_shrinker->base.scan_objects = drm_gem_shmem_shrinker_scan_objects; + shmem_shrinker->base.seeks = DEFAULT_SEEKS; + + mutex_init(&shmem_shrinker->lock); + drm_gem_lru_init(&shmem_shrinker->lru_evictable, &shmem_shrinker->lock); + drm_gem_lru_init(&shmem_shrinker->lru_evicted, &shmem_shrinker->lock); + drm_gem_lru_init(&shmem_shrinker->lru_pinned, &shmem_shrinker->lock); + + err = register_shrinker(&shmem_shrinker->base, shrinker_name); + if (err) { + mutex_destroy(&shmem_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 *shmem_shrinker = &shmem_mm->shrinker; + + unregister_shrinker(&shmem_shrinker->base); + drm_WARN_ON(dev, !list_empty(&shmem_shrinker->lru_evictable.list)); + drm_WARN_ON(dev, !list_empty(&shmem_shrinker->lru_evicted.list)); + drm_WARN_ON(dev, !list_empty(&shmem_shrinker->lru_pinned.list)); + mutex_destroy(&shmem_shrinker->lock); +} + +static int drm_gem_shmem_init(struct drm_device *dev) +{ + int err; + + if (drm_WARN_ON(dev, dev->shmem_mm)) + 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 72193bd734e1..1aa94fff7072 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) && + !refcount_read(&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 7cf4afae2e79..a978f0cb5e84 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; @@ -290,8 +291,13 @@ 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 63e91e8f2d5c..65c99da25048 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -6,6 +6,7 @@ #include #include #include +#include #include #include @@ -13,6 +14,7 @@ #include struct dma_buf_attachment; +struct drm_device; struct drm_mode_create_dumb; struct drm_printer; struct sg_table; @@ -53,8 +55,8 @@ struct drm_gem_shmem_object { * @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; @@ -115,6 +117,12 @@ 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) \ @@ -133,14 +141,22 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma); int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv); +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) && - !refcount_read(&shmem->pages_pin_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 && + refcount_read(&shmem->pages_use_count) && + !refcount_read(&shmem->pages_pin_count) && + !shmem->base.dma_buf && !shmem->base.import_attach && + (shmem->sgt || shmem->evicted); } +int drm_gem_shmem_swapin_locked(struct drm_gem_shmem_object *shmem); + +void drm_gem_shmem_evict_locked(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem); struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem); @@ -284,6 +300,53 @@ static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct v return drm_gem_shmem_mmap(shmem, vma); } +/** + * drm_gem_shmem_object_madvise - unlocked GEM object function for drm_gem_shmem_madvise_locked() + * @obj: GEM object + * @madv: Madvise value + * + * This function wraps drm_gem_shmem_madvise_locked(), providing unlocked variant. + * + * Returns: + * 0 on success or a negative error code on failure. + */ +static inline int drm_gem_shmem_object_madvise(struct drm_gem_object *obj, int madv) +{ + struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); + + return drm_gem_shmem_madvise(shmem, madv); +} + +/** + * 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 */