mac80211: introduce flush operation

We've long lacked a good confirmation that frames
have really gone out, e.g. before going off-channel
for a scan. Add a flush() operation that drivers
can implement to provide that confirmation, and use
it in a few places:
 * before scanning sends the nullfunc frames
 * after scanning sends the nullfunc frames, if any
 * when going idle, to send any pending frames

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index 7a849b920165..977cc7528bc6 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -690,6 +690,27 @@ TRACE_EVENT(drv_ampdu_action,
                 LOCAL_PR_ARG, VIF_PR_ARG, STA_PR_ARG, __entry->action, __entry->tid, __entry->ret
         )
 );
+
+TRACE_EVENT(drv_flush,
+        TP_PROTO(struct ieee80211_local *local, bool drop),
+
+        TP_ARGS(local, drop),
+
+        TP_STRUCT__entry(
+                LOCAL_ENTRY
+                __field(bool, drop)
+        ),
+
+        TP_fast_assign(
+                LOCAL_ASSIGN;
+                __entry->drop = drop;
+        ),
+
+        TP_printk(
+                LOCAL_PR_FMT " drop:%d",
+                LOCAL_PR_ARG, __entry->drop
+        )
+);
 #endif /* !__MAC80211_DRIVER_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH