ircd::ctx: Add minor commentary.

include/ircd/ctx/dock.h

@@ -30,6 +30,10 @@ enum class cv_status
 	no_timeout, timeout
 };
 
+/**
+ * a dock is a condition variable which has no requirement for locking
+ * because the context system does not require mutual exclusion.
+ */
 class dock
 {
 	std::deque<ctx *> q;

include/ircd/ctx/mutex.h

@@ -25,6 +25,11 @@
 namespace ircd {
 namespace ctx  {
 
+/**
+ * The mutex only allows one context to lock it and continue,
+ * additional contexts are queued. This can be used with std::
+ * locking concepts.
+ */
 class mutex
 {
 	bool m;

ircd/ctx.cc

@@ -802,6 +802,7 @@ ircd::ctx::ole::offload(const std::function<void ()> &func)
 			eptr = std::current_exception();
 		}
 
+		// To wake the context on the IRCd thread we give it the kick
 		strand(*context, kick);
 	});