ust: first try at blocking support for consumer

[ust.git] / libtracectl / tracectl.c

diff --git a/libtracectl/tracectl.c b/libtracectl/tracectl.c
index c407be97c13f22f4e99f1a36a7a508924eda5ef4..3732bc03714ae585297dd3b933e86a912b3c7a29 100644 (file)
--- a/libtracectl/tracectl.c
+++ b/libtracectl/tracectl.c
@@ -11,13 +11,10 @@
 #include "tracer.h"
 #include "localerr.h"
 #include "ustcomm.h"
+#include "relay.h" /* FIXME: remove */
 
 //#define USE_CLONE
 
-#define UNIX_PATH_MAX 108
-
-#define SOCKETDIR "/tmp/socks"
-#define SOCKETDIRLEN sizeof(SOCKETDIR)
 #define USTSIGNAL SIGIO
 
 #define MAX_MSG_SIZE (100)
@@ -47,9 +44,6 @@ struct trctl_msg {
        char payload[94];
 };
 
-char mysocketfile[UNIX_PATH_MAX] = "";
-//int pfd = -1;
-
 struct consumer_channel {
        int fd;
        struct ltt_channel_struct *chan;
@@ -184,8 +178,6 @@ void notif_cb(void)
        }
 }
 
-#define CONSUMER_DAEMON_SOCK SOCKETDIR "/ustd"
-
 static int inform_consumer_daemon(void)
 {
        ustcomm_request_consumer(getpid(), "metadata");
@@ -536,6 +528,55 @@ int listener_main(void *p)
                        free(channel_name);
                        free(consumed_old_str);
                }
+               else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
+                       struct ltt_trace_struct *trace;
+                       char trace_name[] = "auto";
+                       int i;
+                       char *channel_name;
+
+                       DBG("get_notifications");
+
+                       channel_name = strdup_malloc(nth_token(recvbuf, 1));
+                       if(channel_name == NULL) {
+                               ERR("put_subbuf_size: cannot parse channel");
+                               goto next_cmd;
+                       }
+
+                       ltt_lock_traces();
+                       trace = _ltt_trace_find(trace_name);
+                       ltt_unlock_traces();
+
+                       if(trace == NULL) {
+                               CPRINTF("cannot find trace!");
+                               return 1;
+                       }
+
+                       for(i=0; i<trace->nr_channels; i++) {
+                               struct rchan *rchan = trace->channels[i].trans_channel_data;
+                               int fd;
+
+                               if(!strcmp(trace->channels[i].channel_name, channel_name)) {
+                                       struct rchan_buf *rbuf = rchan->buf;
+                                       struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
+
+                                       result = fd = ustcomm_app_detach_client(&ustcomm_app, &src);
+                                       if(result == -1) {
+                                               ERR("ustcomm_app_detach_client failed");
+                                               goto next_cmd;
+                                       }
+
+                                       lttbuf->wake_consumer_arg = (void *) fd;
+
+                                       smp_wmb();
+
+                                       lttbuf->call_wake_consumer = 1;
+
+                                       break;
+                               }
+                       }
+
+                       free(channel_name);
+               }
                else {
                        ERR("unable to parse message: %s", recvbuf);
                }
@@ -593,15 +634,15 @@ static int init_socket(void)
 
 static void destroy_socket(void)
 {
-       int result;
-
-       if(mysocketfile[0] == '\0')
-               return;
-
-       result = unlink(mysocketfile);
-       if(result == -1) {
-               PERROR("unlink");
-       }
+//     int result;
+//
+//     if(mysocketfile[0] == '\0')
+//             return;
+//
+//     result = unlink(mysocketfile);
+//     if(result == -1) {
+//             PERROR("unlink");
+//     }
 }
 
 static int init_signal_handler(void)
@@ -646,12 +687,39 @@ static void auto_probe_connect(struct marker *m)
        DBG("just auto connected marker %s %s to probe default", m->channel, m->name);
 }
 
+/* Wake the consumer of a buffer 
+ *
+ * wake_consumer_cb is called in tracing context so it must haste.
+ *
+ * FIXME: don't do a system call here; maybe schedule work to be done
+ * in listener context? Once this is done in listener context, we can
+ * check for the return value of send_message_fd and remove the fd if necessary
+ *
+ * @arg: the buffer
+ * @finished: 0: subbuffer full; 1: buffer being destroyed
+ */
+
+static void wake_consumer_cb(void *arg, int finished)
+{
+       struct ltt_channel_buf_struct *ltt_buf = (struct ltt_channel_buf_struct *) arg;
+       int fd = (int)ACCESS_ONCE(arg);
+
+       if(!finished) {
+               send_message_fd(fd, "consume", NULL);
+       }
+       else {
+               send_message_fd(fd, "destroyed", NULL);
+       }
+}
+
 static void __attribute__((constructor(101))) init0()
 {
        DBG("UST_AUTOPROBE constructor");
        if(getenv("UST_AUTOPROBE")) {
                marker_set_new_marker_cb(auto_probe_connect);
        }
+
+       relay_set_wake_consumer(wake_consumer_cb);
 }
 
 static void fini(void);