Fix: Missing rcu read side lock in consumer

[lttng-tools.git] / src / common / consumer.h

diff --git a/src/common/consumer.h b/src/common/consumer.h
index 8bcf27d2c99166393cfa035ed644b4cd267e60df..dba7765772859bd703adb5ba9e0889759d5fb757 100644 (file)
--- a/src/common/consumer.h
+++ b/src/common/consumer.h
@@ -17,8 +17,8 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#ifndef _LTTNG_CONSUMER_H
-#define _LTTNG_CONSUMER_H
+#ifndef LIB_CONSUMER_H
+#define LIB_CONSUMER_H
 
 #include <limits.h>
 #include <poll.h>
@@ -54,6 +54,8 @@ enum lttng_consumer_command {
        /* inform the consumer to quit when all fd has hang up */
        LTTNG_CONSUMER_STOP,
        LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
+       /* Inform the consumer to kill a specific relayd connection */
+       LTTNG_CONSUMER_DESTROY_RELAYD,
 };
 
 /* State of each fd in consumer */
@@ -81,7 +83,6 @@ struct lttng_consumer_channel {
        void *mmap_base;
        size_t mmap_len;
        struct lttng_ust_shm_handle *handle;
-       int nr_streams;
        int wait_fd_is_copy;
        int cpucount;
 };
@@ -128,6 +129,8 @@ struct lttng_consumer_stream {
        unsigned int metadata_flag;
        /* Used when the stream is set for network streaming */
        uint64_t relayd_stream_id;
+       /* Next sequence number to use for trace packet */
+       uint64_t next_net_seq_num;
 };
 
 /*
@@ -138,9 +141,30 @@ struct consumer_relayd_sock_pair {
        int net_seq_idx;
        /* Number of stream associated with this relayd */
        unsigned int refcount;
+
+       /*
+        * This flag indicates whether or not we should destroy this object. The
+        * destruction should ONLY occurs when this flag is set and the refcount is
+        * set to zero.
+        */
+       unsigned int destroy_flag;
+
+       /*
+        * Mutex protecting the control socket to avoid out of order packets
+        * between threads sending data to the relayd. Since metadata data is sent
+        * over that socket, at least two sendmsg() are needed (header + data)
+        * creating a race for packets to overlap between threads using it.
+        */
        pthread_mutex_t ctrl_sock_mutex;
-       /* Sockets information */
+
+       /* Control socket. Command and metadata are passed over it */
        struct lttcomm_sock control_sock;
+
+       /*
+        * We don't need a mutex at this point since we only splice or write single
+        * large chunk of data with a header appended at the begining. Moreover,
+        * this socket is for now only used in a single thread.
+        */
        struct lttcomm_sock data_sock;
        struct lttng_ht_node_ulong node;
 };
@@ -199,10 +223,13 @@ struct lttng_consumer_local_data {
        char *consumer_command_sock_path;
        /* communication with splice */
        int consumer_thread_pipe[2];
+       int consumer_splice_metadata_pipe[2];
        /* pipe to wake the poll thread when necessary */
        int consumer_poll_pipe[2];
        /* to let the signal handler wake up the fd receiver thread */
        int consumer_should_quit[2];
+       /* Metadata poll thread pipe. Transfer metadata stream to it */
+       int consumer_metadata_pipe[2];
 };
 
 /*
@@ -293,8 +320,7 @@ extern int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 
 extern int consumer_update_poll_array(
                struct lttng_consumer_local_data *ctx, struct pollfd **pollfd,
-               struct lttng_consumer_stream **local_consumer_streams,
-               struct lttng_ht *metadata_ht);
+               struct lttng_consumer_stream **local_consumer_streams);
 
 extern struct lttng_consumer_stream *consumer_allocate_stream(
                int channel_key, int stream_key,
@@ -320,7 +346,6 @@ extern struct lttng_consumer_channel *consumer_allocate_channel(
 int consumer_add_channel(struct lttng_consumer_channel *channel);
 
 /* lttng-relayd consumer command */
-int consumer_add_relayd(struct consumer_relayd_sock_pair *relayd);
 struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair(
                int net_seq_idx);
 struct consumer_relayd_sock_pair *consumer_find_relayd(int key);
@@ -337,10 +362,12 @@ extern struct lttng_consumer_local_data *lttng_consumer_create(
 extern void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 extern ssize_t lttng_consumer_on_read_subbuffer_mmap(
                struct lttng_consumer_local_data *ctx,
-               struct lttng_consumer_stream *stream, unsigned long len);
+               struct lttng_consumer_stream *stream, unsigned long len,
+               unsigned long padding);
 extern ssize_t lttng_consumer_on_read_subbuffer_splice(
                struct lttng_consumer_local_data *ctx,
-               struct lttng_consumer_stream *stream, unsigned long len);
+               struct lttng_consumer_stream *stream, unsigned long len,
+               unsigned long padding);
 extern int lttng_consumer_take_snapshot(struct lttng_consumer_local_data *ctx,
                struct lttng_consumer_stream *stream);
 extern int lttng_consumer_get_produced_snapshot(
@@ -355,5 +382,10 @@ extern int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
                struct lttng_consumer_local_data *ctx);
 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
+int consumer_add_relayd_socket(int net_seq_idx, int sock_type,
+               struct lttng_consumer_local_data *ctx, int sock,
+               struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock);
+void consumer_flag_relayd_for_destroy(
+               struct consumer_relayd_sock_pair *relayd);
 
-#endif /* _LTTNG_CONSUMER_H */
+#endif /* LIB_CONSUMER_H */