[Intel-gfx] [PATCH i-g-t] debugfs: Define DROP_RCU

[Chris Wilson]

Corresponding kernel commit 54895010a893 ("drm/i915: Add an rcu_barrier
option to i915_drop_caches")

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld at gmail.com>
---
 lib/igt_debugfs.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/igt_debugfs.h b/lib/igt_debugfs.h
index 36b638177..a56f09dd2 100644
--- a/lib/igt_debugfs.h
+++ b/lib/igt_debugfs.h
@@ -172,6 +172,13 @@ void igt_require_hpd_storm_ctl(int fd);
  * Reset the global request seqno counter back to 0
  */
 #define DROP_RESET_SEQNO 0x100
+/**
+ * DROP_RCU:
+ *
+ * Performs rcu_barrier() and waits for an RCU grace period to complete,
+ * which will flush any RCU callbacks and deferred tasks.
+ */
+#define DROP_RCU 0x200
 /**
  * DROP_ALL:
  *
-- 
2.23.0