From 96a7b60f6ddb2bc966fac800c1dd18876a6e3c3f Mon Sep 17 00:00:00 2001 From: Christian König Date: Thu, 26 Jan 2023 11:26:38 +0100 Subject: drm: remove dumb_destroy callback MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Not used by any driver any more. Signed-off-by: Christian König Reviewed-by: Thomas Zimmermann Tested-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20230126102814.8722-2-christian.koenig@amd.com --- drivers/gpu/drm/drm_gem.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'drivers/gpu/drm/drm_gem.c') diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 59a0bb5ebd852..aa15c52ae1821 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -336,13 +336,6 @@ out: } EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset); -int drm_gem_dumb_destroy(struct drm_file *file, - struct drm_device *dev, - u32 handle) -{ - return drm_gem_handle_delete(file, handle); -} - /** * drm_gem_handle_create_tail - internal functions to create a handle * @file_priv: drm file-private structure to register the handle for -- cgit v1.2.3 From 9630b585b607bd26f505d34620b14d75b9a5af7d Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 4 Nov 2022 19:04:59 +0300 Subject: drm/msm/gem: Prevent blocking within shrinker loop Consider this scenario: 1. APP1 continuously creates lots of small GEMs 2. APP2 triggers `drop_caches` 3. Shrinker starts to evict APP1 GEMs, while APP1 produces new purgeable GEMs 4. msm_gem_shrinker_scan() returns non-zero number of freed pages and causes shrinker to try shrink more 5. msm_gem_shrinker_scan() returns non-zero number of freed pages again, goto 4 6. The APP2 is blocked in `drop_caches` until APP1 stops producing purgeable GEMs To prevent this blocking scenario, check number of remaining pages that GPU shrinker couldn't release due to a GEM locking contention or shrinking rejection. If there are no remaining pages left to shrink, then there is no need to free up more pages and shrinker may break out from the loop. This problem was found during shrinker/madvise IOCTL testing of virtio-gpu driver. The MSM driver is affected in the same way. Reviewed-by: Rob Clark Reviewed-by: Thomas Zimmermann Fixes: b352ba54a820 ("drm/msm/gem: Convert to using drm_gem_lru") Signed-off-by: Dmitry Osipenko Link: https://lore.kernel.org/all/20230108210445.3948344-2-dmitry.osipenko@collabora.com/ --- drivers/gpu/drm/drm_gem.c | 9 +++++++-- drivers/gpu/drm/msm/msm_gem_shrinker.c | 11 +++++++++-- include/drm/drm_gem.h | 4 +++- 3 files changed, 19 insertions(+), 5 deletions(-) (limited to 'drivers/gpu/drm/drm_gem.c') diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index b8db675e7fb5e..b0246a8480068 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1375,10 +1375,13 @@ EXPORT_SYMBOL(drm_gem_lru_move_tail); * * @lru: The LRU to scan * @nr_to_scan: The number of pages to try to reclaim + * @remaining: The number of pages left to reclaim, should be initialized by caller * @shrink: Callback to try to shrink/reclaim the object. */ unsigned long -drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan, +drm_gem_lru_scan(struct drm_gem_lru *lru, + unsigned int nr_to_scan, + unsigned long *remaining, bool (*shrink)(struct drm_gem_object *obj)) { struct drm_gem_lru still_in_lru; @@ -1417,8 +1420,10 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan, * hit shrinker in response to trying to get backing pages * for this obj (ie. while it's lock is already held) */ - if (!dma_resv_trylock(obj->resv)) + if (!dma_resv_trylock(obj->resv)) { + *remaining += obj->size >> PAGE_SHIFT; goto tail; + } if (shrink(obj)) { freed += obj->size >> PAGE_SHIFT; diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c index 051bdbc093cf9..f38296ad87434 100644 --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c @@ -107,6 +107,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) bool (*shrink)(struct drm_gem_object *obj); bool cond; unsigned long freed; + unsigned long remaining; } stages[] = { /* Stages of progressively more aggressive/expensive reclaim: */ { &priv->lru.dontneed, purge, true }, @@ -116,14 +117,18 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) }; long nr = sc->nr_to_scan; unsigned long freed = 0; + unsigned long remaining = 0; for (unsigned i = 0; (nr > 0) && (i < ARRAY_SIZE(stages)); i++) { if (!stages[i].cond) continue; stages[i].freed = - drm_gem_lru_scan(stages[i].lru, nr, stages[i].shrink); + drm_gem_lru_scan(stages[i].lru, nr, + &stages[i].remaining, + stages[i].shrink); nr -= stages[i].freed; freed += stages[i].freed; + remaining += stages[i].remaining; } if (freed) { @@ -132,7 +137,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) stages[3].freed); } - return (freed > 0) ? freed : SHRINK_STOP; + return (freed > 0 && remaining > 0) ? freed : SHRINK_STOP; } #ifdef CONFIG_DEBUG_FS @@ -182,10 +187,12 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr) NULL, }; unsigned idx, unmapped = 0; + unsigned long remaining = 0; for (idx = 0; lrus[idx] && unmapped < vmap_shrink_limit; idx++) { unmapped += drm_gem_lru_scan(lrus[idx], vmap_shrink_limit - unmapped, + &remaining, vmap_shrink); } diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index a17c2f903f81e..b46ade8124436 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -475,7 +475,9 @@ int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock); void drm_gem_lru_remove(struct drm_gem_object *obj); void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj); -unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan, +unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, + unsigned int nr_to_scan, + unsigned long *remaining, bool (*shrink)(struct drm_gem_object *obj)); #endif /* __DRM_GEM_H__ */ -- cgit v1.2.3 From 7eabaa892d9c57ad9b2946f923d781e8a16f8e88 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Wed, 16 Nov 2022 17:07:50 +0300 Subject: drm/gem: Add evict() callback to drm_gem_object_funcs Add new common evict() callback to drm_gem_object_funcs and corresponding drm_gem_object_evict() helper. This is a first step on a way to providing common GEM-shrinker API for DRM drivers. Reviewed-by: Thomas Zimmermann Suggested-by: Thomas Zimmermann Signed-off-by: Dmitry Osipenko Link: https://lore.kernel.org/all/20230108210445.3948344-4-dmitry.osipenko@collabora.com/ --- drivers/gpu/drm/drm_gem.c | 18 ++++++++++++++++++ include/drm/drm_gem.h | 12 ++++++++++++ 2 files changed, 30 insertions(+) (limited to 'drivers/gpu/drm/drm_gem.c') diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index aa15c52ae1821..9b2e7864dbd0a 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1459,3 +1459,21 @@ tail: return freed; } EXPORT_SYMBOL(drm_gem_lru_scan); + +/** + * drm_gem_evict - helper to evict backing pages for a GEM object + * @obj: obj in question + */ +int drm_gem_evict(struct drm_gem_object *obj) +{ + dma_resv_assert_held(obj->resv); + + if (!dma_resv_test_signaled(obj->resv, DMA_RESV_USAGE_READ)) + return -EBUSY; + + if (obj->funcs->evict) + return obj->funcs->evict(obj); + + return 0; +} +EXPORT_SYMBOL(drm_gem_evict); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 772a4adf52870..c76e651f2d440 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -164,6 +164,16 @@ struct drm_gem_object_funcs { */ int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma); + /** + * @evict: + * + * Evicts gem object out from memory. Used by the drm_gem_object_evict() + * helper. Returns 0 on success, -errno otherwise. + * + * This callback is optional. + */ + int (*evict)(struct drm_gem_object *obj); + /** * @vm_ops: * @@ -479,4 +489,6 @@ void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj); unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan, bool (*shrink)(struct drm_gem_object *obj)); +int drm_gem_evict(struct drm_gem_object *obj); + #endif /* __DRM_GEM_H__ */ -- cgit v1.2.3 From b43f9afb81262d6c150152e2831a000b3c1b5d11 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Mon, 20 Mar 2023 07:43:28 -0700 Subject: drm/gem: Export drm_gem_lru_move_tail_locked() Export the locked version or lru's move_tail(). Signed-off-by: Rob Clark Patchwork: https://patchwork.freedesktop.org/patch/527835/ Link: https://lore.kernel.org/r/20230320144356.803762-7-robdclark@gmail.com --- drivers/gpu/drm/drm_gem.c | 11 ++++++++++- include/drm/drm_gem.h | 1 + 2 files changed, 11 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/drm_gem.c') diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index ee3e11e7177dd..0f7f928f21da1 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1337,7 +1337,15 @@ drm_gem_lru_remove(struct drm_gem_object *obj) } EXPORT_SYMBOL(drm_gem_lru_remove); -static void +/** + * drm_gem_lru_move_tail_locked - move the object to the tail of the LRU + * + * Like &drm_gem_lru_move_tail but lru lock must be held + * + * @lru: The LRU to move the object into. + * @obj: The GEM object to move into this LRU + */ +void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj) { lockdep_assert_held_once(lru->lock); @@ -1349,6 +1357,7 @@ drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj list_add_tail(&obj->lru_node, &lru->list); obj->lru = lru; } +EXPORT_SYMBOL(drm_gem_lru_move_tail_locked); /** * drm_gem_lru_move_tail - move the object to the tail of the LRU diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index c76e651f2d440..189fd618ca65a 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -485,6 +485,7 @@ int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock); void drm_gem_lru_remove(struct drm_gem_object *obj); +void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj); void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj); unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan, bool (*shrink)(struct drm_gem_object *obj)); -- cgit v1.2.3