binder: add more debug info when allocation fails.

Display information about allocated/free space whenever
binder buffer allocation fails on synchronous
transactions.
Signed-off-by: Martijn Coenen <maco@android.com>
Signed-off-by: Siqi Lin <siqilin@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/android/binder_alloc.c

@@ -337,8 +337,36 @@ struct binder_buffer *binder_alloc_new_buf_locked(struct binder_alloc *alloc,
 		}
 	}
 	if (best_fit == NULL) {
+		size_t allocated_buffers = 0;
+		size_t largest_alloc_size = 0;
+		size_t total_alloc_size = 0;
+		size_t free_buffers = 0;
+		size_t largest_free_size = 0;
+		size_t total_free_size = 0;
+
+		for (n = rb_first(&alloc->allocated_buffers); n != NULL;
+		     n = rb_next(n)) {
+			buffer = rb_entry(n, struct binder_buffer, rb_node);
+			buffer_size = binder_alloc_buffer_size(alloc, buffer);
+			allocated_buffers++;
+			total_alloc_size += buffer_size;
+			if (buffer_size > largest_alloc_size)
+				largest_alloc_size = buffer_size;
+		}
+		for (n = rb_first(&alloc->free_buffers); n != NULL;
+		     n = rb_next(n)) {
+			buffer = rb_entry(n, struct binder_buffer, rb_node);
+			buffer_size = binder_alloc_buffer_size(alloc, buffer);
+			free_buffers++;
+			total_free_size += buffer_size;
+			if (buffer_size > largest_free_size)
+				largest_free_size = buffer_size;
+		}
 		pr_err("%d: binder_alloc_buf size %zd failed, no address space\n",
 			alloc->pid, size);
+		pr_err("allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n",
+		       total_alloc_size, allocated_buffers, largest_alloc_size,
+		       total_free_size, free_buffers, largest_free_size);
 		return ERR_PTR(-ENOSPC);
 	}
 	if (n == NULL) {
@@ -698,9 +726,10 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
 static void print_binder_buffer(struct seq_file *m, const char *prefix,
 				struct binder_buffer *buffer)
 {
-	seq_printf(m, "%s %d: %pK size %zd:%zd %s\n",
+	seq_printf(m, "%s %d: %pK size %zd:%zd:%zd %s\n",
 		   prefix, buffer->debug_id, buffer->data,
 		   buffer->data_size, buffer->offsets_size,
+		   buffer->extra_buffers_size,
 		   buffer->transaction ? "active" : "delivered");
 }