Reduce contention of queued_data_mutex.

[cubemap] / stream.h

diff --git a/stream.h b/stream.h
index f2ba5d43dccc561ef530cf2445ea302f3a555e05..2cdba11ad46b48a1d07801dccd7821efa11568ce 100644 (file)
--- a/stream.h
+++ b/stream.h
@@ -34,6 +34,11 @@ struct Stream {
        // Changes the backlog size, restructuring the data as needed.
        void set_backlog_size(size_t new_size);
 
+       // Mutex protecting <queued_data> and <queued_data_last_starting_point>.
+       // Note that if you want to hold both this and the owning server's
+       // <mutex> you will need to take <mutex> before this one.
+       mutable pthread_mutex_t queued_data_mutex;
+
        std::string url;
 
        // The HTTP response header, without the trailing double newline.
@@ -79,12 +84,12 @@ struct Stream {
        // What pool to fetch marks from, or NULL.
        MarkPool *mark_pool;
 
-       // Queued data, if any. Protected by the owning Server's <queued_data_mutex>.
+       // Queued data, if any. Protected by <queued_data_mutex>.
        // The data pointers in the iovec are owned by us.
        std::vector<iovec> queued_data;
 
        // Index of the last element in queued_data that is suitable to start streaming at.
-       // -1 if none.
+       // -1 if none. Protected by <queued_data_mutex>.
        int queued_data_last_starting_point;
 
        // Put client to sleep, since there is no more data for it; we will on
@@ -94,11 +99,10 @@ struct Stream {
 
        // Add more data to <queued_data>, adding Metacube headers if needed.
        // Does not take ownership of <data>.
-       // You should hold the owning Server's <queued_data_mutex>.
        void add_data_deferred(const char *data, size_t bytes, StreamStartSuitability suitable_for_stream_start);
 
        // Add queued data to the stream, if any.
-       // You should hold the owning Server's <mutex> _and_ <queued_data_mutex>.
+       // You should hold the owning Server's <mutex>.
        void process_queued_data();
 
 private: