drm/i915: split out i915_list_util.h

Move list related utilities from i915_utils.h to separate new file
i915_list_util.h. Clean up related includes.

Note: Arguably none of this should exist in i915 in the first place. At
least isolate it better.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://lore.kernel.org/r/d7526809735194137116682f37cfa126a6a87ec9.1757582214.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Author: jnikula

drivers/gpu/drm/i915/gt/intel_execlists_submission.c

@@ -112,6 +112,7 @@
 
 #include "gen8_engine_cs.h"
 #include "i915_drv.h"
+#include "i915_list_util.h"
 #include "i915_reg.h"
 #include "i915_timer_util.h"
 #include "i915_trace.h"

drivers/gpu/drm/i915/gt/intel_gt_buffer_pool.c

@@ -7,6 +7,7 @@
 #include "gem/i915_gem_object.h"
 
 #include "i915_drv.h"
+#include "i915_list_util.h"
 #include "intel_engine_pm.h"
 #include "intel_gt_buffer_pool.h"
 

drivers/gpu/drm/i915/gt/intel_timeline.h

@@ -9,8 +9,8 @@
 #include <linux/lockdep.h>
 
 #include "i915_active.h"
+#include "i915_list_util.h"
 #include "i915_syncmap.h"
-#include "i915_utils.h"
 #include "intel_timeline_types.h"
 
 struct drm_printer;

drivers/gpu/drm/i915/i915_list_util.h

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: MIT */
+/* Copyright © 2025 Intel Corporation */
+
+#ifndef __I915_LIST_UTIL_H__
+#define __I915_LIST_UTIL_H__
+
+#include <linux/list.h>
+#include <asm/rwonce.h>
+
+static inline void __list_del_many(struct list_head *head,
+				   struct list_head *first)
+{
+	first->prev = head;
+	WRITE_ONCE(head->next, first);
+}
+
+static inline int list_is_last_rcu(const struct list_head *list,
+				   const struct list_head *head)
+{
+	return READ_ONCE(list->next) == head;
+}
+
+#endif /* __I915_LIST_UTIL_H__ */

drivers/gpu/drm/i915/i915_utils.h

@@ -25,7 +25,6 @@
 #ifndef __I915_UTILS_H
 #define __I915_UTILS_H
 
-#include <linux/list.h>
 #include <linux/overflow.h>
 #include <linux/sched.h>
 #include <linux/string_helpers.h>
@@ -101,19 +100,6 @@ static inline bool is_power_of_2_u64(u64 n)
 	return (n != 0 && ((n & (n - 1)) == 0));
 }
 
-static inline void __list_del_many(struct list_head *head,
-				   struct list_head *first)
-{
-	first->prev = head;
-	WRITE_ONCE(head->next, first);
-}
-
-static inline int list_is_last_rcu(const struct list_head *list,
-				   const struct list_head *head)
-{
-	return READ_ONCE(list->next) == head;
-}
-
 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
 {
 	unsigned long j = msecs_to_jiffies(m);