i915: Move list_count() to list.h as list_count_nodes() for broader use

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>
Link: https://lore.kernel.org/r/20221130134838.23805-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index c33e0d7..0dcf4ac 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -2094,17 +2094,6 @@ 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);
@@ -2279,8 +2268,8 @@ 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 6176205..f10344d 100644 (file)
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -656,6 +656,21 @@ static inline void list_splice_tail_init(struct list_head *list,
             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
  * @head:      the head for your list.