Merge tag 'drm-misc-next-2021-09-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for $kernel-version:

UAPI Changes:

Cross-subsystem Changes:
  - dma-buf: Avoid a warning with some allocations, Remove
    DMA_FENCE_TRACE macros

Core Changes:
  - bridge: New helper to git rid of panels in drivers
  - fence: Improve dma_fence_add_callback documentation, Improve
    dma_fence_ops->wait documentation
  - ioctl: Unexport drm_ioctl_permit
  - lease: Documentation improvements
  - fourcc: Add new macro to determine the modifier vendor
  - quirks: Add the Steam Deck, Chuwi HiBook, Chuwi Hi10 Pro, Samsung
    Galaxy Book 10.6, KD Kurio Smart C15200 2-in-1, Lenovo Ideapad D330
  - resv: Improve the documentation
  - shmem-helpers: Allocate WC pages on x86, Switch to vmf_insert_pfn
  - sched: Fix for a timer being canceled too soon, Avoid null pointer
    derefence if the fence is null in drm_sched_fence_free, Convert
    drivers to rely on its dependency tracking
  - ttm: Switch to kerneldoc, new helper to clear all DMA mappings, pool
    shrinker optitimization, Remove ttm_tt_destroy_common, Fix for
    unbinding on multiple drivers

Driver Changes:
  - bochs: New PCI IDs
  - msm: Fence ordering impromevemnts
  - stm: Add layer alpha support, zpos
  - v3d: Fix for a Vulkan CTS failure
  - vc4: Conversion to the new bridge helpers
  - vgem: Use shmem helpers
  - virtio: Support mapping exported vram
  - zte: Remove obsolete driver

  - bridge: Probe improvements for it66121, enable DSI EOTP for anx7625,
    errors propagation improvements for anx7625

  - panels: 60fps mode for otm8009a, New driver for Samsung S6D27A1

Signed-off-by: Dave Airlie <airlied@redhat.com>

# gpg: Signature made Thu 16 Sep 2021 17:30:50 AEST
# gpg:                using EDDSA key 5C1337A45ECA9AEB89060E9EE3EF0D6F671851C5
# gpg: Can't check signature: No public key
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916073132.ptbbmjetm7v3ufq3@gilmour

1 files changed, 22 insertions, 18 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c
index 82cbb29a05aa..c961a788b519 100644
--- a/drivers/gpu/drm/ttm/ttm_pool.c
+++ b/drivers/gpu/drm/ttm/ttm_pool.c
@@ -70,7 +70,7 @@ static struct ttm_pool_type global_uncached[MAX_ORDER];
 static struct ttm_pool_type global_dma32_write_combined[MAX_ORDER];
 static struct ttm_pool_type global_dma32_uncached[MAX_ORDER];
 
-static struct mutex shrinker_lock;
+static spinlock_t shrinker_lock;
 static struct list_head shrinker_list;
 static struct shrinker mm_shrinker;
 
@@ -263,9 +263,9 @@ static void ttm_pool_type_init(struct ttm_pool_type *pt, struct ttm_pool *pool,
 	spin_lock_init(&pt->lock);
 	INIT_LIST_HEAD(&pt->pages);
 
-	mutex_lock(&shrinker_lock);
+	spin_lock(&shrinker_lock);
 	list_add_tail(&pt->shrinker_list, &shrinker_list);
-	mutex_unlock(&shrinker_lock);
+	spin_unlock(&shrinker_lock);
 }
 
 /* Remove a pool_type from the global shrinker list and free all pages */
@@ -273,9 +273,9 @@ static void ttm_pool_type_fini(struct ttm_pool_type *pt)
 {
 	struct page *p;
 
-	mutex_lock(&shrinker_lock);
+	spin_lock(&shrinker_lock);
 	list_del(&pt->shrinker_list);
-	mutex_unlock(&shrinker_lock);
+	spin_unlock(&shrinker_lock);
 
 	while ((p = ttm_pool_type_take(pt)))
 		ttm_pool_free_page(pt->pool, pt->caching, pt->order, p);
@@ -313,24 +313,23 @@ static struct ttm_pool_type *ttm_pool_select_type(struct ttm_pool *pool,
 static unsigned int ttm_pool_shrink(void)
 {
 	struct ttm_pool_type *pt;
-	unsigned int num_freed;
+	unsigned int num_pages;
 	struct page *p;
 
-	mutex_lock(&shrinker_lock);
+	spin_lock(&shrinker_lock);
 	pt = list_first_entry(&shrinker_list, typeof(*pt), shrinker_list);
+	list_move_tail(&pt->shrinker_list, &shrinker_list);
+	spin_unlock(&shrinker_lock);
 
 	p = ttm_pool_type_take(pt);
 	if (p) {
 		ttm_pool_free_page(pt->pool, pt->caching, pt->order, p);
-		num_freed = 1 << pt->order;
+		num_pages = 1 << pt->order;
 	} else {
-		num_freed = 0;
+		num_pages = 0;
 	}
 
-	list_move_tail(&pt->shrinker_list, &shrinker_list);
-	mutex_unlock(&shrinker_lock);
-
-	return num_freed;
+	return num_pages;
 }
 
 /* Return the allocation order based for a page */
@@ -531,6 +530,11 @@ void ttm_pool_fini(struct ttm_pool *pool)
 			for (j = 0; j < MAX_ORDER; ++j)
 				ttm_pool_type_fini(&pool->caching[i].orders[j]);
 	}
+
+	/* We removed the pool types from the LRU, but we need to also make sure
+	 * that no shrinker is concurrently freeing pages from the pool.
+	 */
+	synchronize_shrinkers();
 }
 
 /* As long as pages are available make sure to release at least one */
@@ -605,7 +609,7 @@ static int ttm_pool_debugfs_globals_show(struct seq_file *m, void *data)
 {
 	ttm_pool_debugfs_header(m);
 
-	mutex_lock(&shrinker_lock);
+	spin_lock(&shrinker_lock);
 	seq_puts(m, "wc\t:");
 	ttm_pool_debugfs_orders(global_write_combined, m);
 	seq_puts(m, "uc\t:");
@@ -614,7 +618,7 @@ static int ttm_pool_debugfs_globals_show(struct seq_file *m, void *data)
 	ttm_pool_debugfs_orders(global_dma32_write_combined, m);
 	seq_puts(m, "uc 32\t:");
 	ttm_pool_debugfs_orders(global_dma32_uncached, m);
-	mutex_unlock(&shrinker_lock);
+	spin_unlock(&shrinker_lock);
 
 	ttm_pool_debugfs_footer(m);
 
@@ -641,7 +645,7 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m)
 
 	ttm_pool_debugfs_header(m);
 
-	mutex_lock(&shrinker_lock);
+	spin_lock(&shrinker_lock);
 	for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) {
 		seq_puts(m, "DMA ");
 		switch (i) {
@@ -657,7 +661,7 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m)
 		}
 		ttm_pool_debugfs_orders(pool->caching[i].orders, m);
 	}
-	mutex_unlock(&shrinker_lock);
+	spin_unlock(&shrinker_lock);
 
 	ttm_pool_debugfs_footer(m);
 	return 0;
@@ -694,7 +698,7 @@ int ttm_pool_mgr_init(unsigned long num_pages)
 	if (!page_pool_size)
 		page_pool_size = num_pages;
 
-	mutex_init(&shrinker_lock);
+	spin_lock_init(&shrinker_lock);
 	INIT_LIST_HEAD(&shrinker_list);
 
 	for (i = 0; i < MAX_ORDER; ++i) {