1 files changed, 41 insertions, 38 deletions

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 29486eb9d1dc..ef7c90b7a346 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -47,6 +47,8 @@
 #ifndef PREALLOC_DMA_DEBUG_ENTRIES
 #define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
 #endif
+/* If the pool runs out, add this many new entries at once */
+#define DMA_DEBUG_DYNAMIC_ENTRIES 256
 
 enum {
 	dma_debug_single,
@@ -646,6 +648,34 @@ static void add_dma_entry(struct dma_debug_entry *entry)
 	 */
 }
 
+static int dma_debug_create_entries(u32 num_entries, gfp_t gfp)
+{
+	struct dma_debug_entry *entry, *next_entry;
+	int i;
+
+	for (i = 0; i < num_entries; ++i) {
+		entry = kzalloc(sizeof(*entry), gfp);
+		if (!entry)
+			goto out_err;
+
+		list_add_tail(&entry->list, &free_entries);
+	}
+
+	num_free_entries += num_entries;
+	nr_total_entries += num_entries;
+
+	return 0;
+
+out_err:
+
+	list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
+		list_del(&entry->list);
+		kfree(entry);
+	}
+
+	return -ENOMEM;
+}
+
 static struct dma_debug_entry *__dma_entry_alloc(void)
 {
 	struct dma_debug_entry *entry;
@@ -672,12 +702,14 @@ static struct dma_debug_entry *dma_entry_alloc(void)
 	unsigned long flags;
 
 	spin_lock_irqsave(&free_entries_lock, flags);
-
-	if (list_empty(&free_entries)) {
-		global_disable = true;
-		spin_unlock_irqrestore(&free_entries_lock, flags);
-		pr_err("debugging out of memory - disabling\n");
-		return NULL;
+	if (num_free_entries == 0) {
+		if (dma_debug_create_entries(DMA_DEBUG_DYNAMIC_ENTRIES,
+					     GFP_ATOMIC)) {
+			global_disable = true;
+			spin_unlock_irqrestore(&free_entries_lock, flags);
+			pr_err("debugging out of memory - disabling\n");
+			return NULL;
+		}
 	}
 
 	entry = __dma_entry_alloc();
@@ -764,36 +796,6 @@ int dma_debug_resize_entries(u32 num_entries)
  *   2. Preallocate a given number of dma_debug_entry structs
  */
 
-static int prealloc_memory(u32 num_entries)
-{
-	struct dma_debug_entry *entry, *next_entry;
-	int i;
-
-	for (i = 0; i < num_entries; ++i) {
-		entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-		if (!entry)
-			goto out_err;
-
-		list_add_tail(&entry->list, &free_entries);
-	}
-
-	num_free_entries = num_entries;
-	min_free_entries = num_entries;
-
-	pr_info("preallocated %d debug entries\n", num_entries);
-
-	return 0;
-
-out_err:
-
-	list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
-		list_del(&entry->list);
-		kfree(entry);
-	}
-
-	return -ENOMEM;
-}
-
 static ssize_t filter_read(struct file *file, char __user *user_buf,
 			   size_t count, loff_t *ppos)
 {
@@ -1038,14 +1040,15 @@ static int dma_debug_init(void)
 		return 0;
 	}
 
-	if (prealloc_memory(nr_prealloc_entries) != 0) {
+	if (dma_debug_create_entries(nr_prealloc_entries, GFP_KERNEL) != 0) {
 		pr_err("debugging out of memory error - disabled\n");
 		global_disable = true;
 
 		return 0;
 	}
 
-	nr_total_entries = num_free_entries;
+	min_free_entries = num_free_entries;
+	pr_info("preallocated %d debug entries\n", nr_total_entries);
 
 	dma_debug_initialized = true;