[PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

Some of the existing users, and definitely will be new ones, want to
count existing nodes in the list. Provide a generic API for that by
moving code from i915 to list.h.

Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v5: added tag (Lucas), renamed API to list_count_nodes() (LKP)
v4: fixed prototype when converting to static inline
v3: added tag (Jani), changed to be static inline (Mike)
v2: dropped the duplicate code in i915 (LKP)
 drivers/gpu/drm/i915/gt/intel_engine_cs.c | 15 ++-------------
 include/linux/list.h                      | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 1f7188129cd1..370164363b0d 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -2004,17 +2004,6 @@ static void print_request_ring(struct drm_printer *m, struct i915_request *rq)
 	}
 }
 
-static unsigned long list_count(struct list_head *list)
-{
-	struct list_head *pos;
-	unsigned long count = 0;
-
-	list_for_each(pos, list)
-		count++;
-
-	return count;
-}
-
 static unsigned long read_ul(void *p, size_t x)
 {
 	return *(unsigned long *)(p + x);
@@ -2189,8 +2178,8 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
 	engine_dump_active_requests(engine, m);
 
-	drm_printf(m, "\tOn hold?: %lu\n",
-		   list_count(&engine->sched_engine->hold));
+	drm_printf(m, "\tOn hold?: %zu\n",
+		   list_count_nodes(&engine->sched_engine->hold));
 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
 
 	drm_printf(m, "\tMMIO base:  0x%08x\n", engine->mmio_base);
diff --git a/include/linux/list.h b/include/linux/list.h
index 61762054b4be..f10344dbad4d 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -655,6 +655,21 @@ static inline void list_splice_tail_init(struct list_head *list,
 	     !list_is_head(pos, (head)); \
 	     pos = n, n = pos->prev)
 
+/**
+ * list_count_nodes - count nodes in the list
+ * @head:	the head for your list.
+ */
+static inline size_t list_count_nodes(struct list_head *head)
+{
+	struct list_head *pos;
+	size_t count = 0;
+
+	list_for_each(pos, head)
+		count++;
+
+	return count;
+}
+
 /**
  * list_entry_is_head - test if the entry points to the head of the list
  * @pos:	the type * to cursor
-- 
2.35.1