Fix: rotation may never complete in per-PID buffering mode

[lttng-tools.git] / src / bin / lttng-sessiond / channel.c

diff --git a/src/bin/lttng-sessiond/channel.c b/src/bin/lttng-sessiond/channel.c
index f35410e3ae3fe85c1a7b05e87d3c25e5865795ae..5aa0cd82b60884782e7a60644c0715e9b8e10176 100644 (file)
--- a/src/bin/lttng-sessiond/channel.c
+++ b/src/bin/lttng-sessiond/channel.c
@@ -41,6 +41,7 @@ struct lttng_channel *channel_new_default_attr(int dom,
 {
        struct lttng_channel *chan;
        const char *channel_name = DEFAULT_CHANNEL_NAME;
+       struct lttng_channel_extended *extended_attr = NULL;
 
        chan = zmalloc(sizeof(struct lttng_channel));
        if (chan == NULL) {
@@ -48,6 +49,14 @@ struct lttng_channel *channel_new_default_attr(int dom,
                goto error_alloc;
        }
 
+       extended_attr = zmalloc(sizeof(struct lttng_channel_extended));
+       if (!extended_attr) {
+               PERROR("zmalloc channel extended init");
+               goto error;
+       }
+
+       chan->attr.extended.ptr = extended_attr;
+
        /* Same for all domains. */
        chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
        chan->attr.tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE;
@@ -63,6 +72,9 @@ struct lttng_channel *channel_new_default_attr(int dom,
                chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
                chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
                chan->attr.live_timer_interval = DEFAULT_KERNEL_CHANNEL_LIVE_TIMER;
+               extended_attr->blocking_timeout = DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT;
+               extended_attr->monitor_timer_interval =
+                       DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER;
                break;
        case LTTNG_DOMAIN_JUL:
                channel_name = DEFAULT_JUL_CHANNEL_NAME;
@@ -86,6 +98,9 @@ common_ust:
                                DEFAULT_UST_UID_CHANNEL_READ_TIMER;
                        chan->attr.live_timer_interval =
                                DEFAULT_UST_UID_CHANNEL_LIVE_TIMER;
+                       extended_attr->blocking_timeout = DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT;
+                       extended_attr->monitor_timer_interval =
+                               DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER;
                        break;
                case LTTNG_BUFFER_PER_PID:
                default:
@@ -97,7 +112,10 @@ common_ust:
                        chan->attr.read_timer_interval =
                                DEFAULT_UST_PID_CHANNEL_READ_TIMER;
                        chan->attr.live_timer_interval =
-                               DEFAULT_UST_UID_CHANNEL_LIVE_TIMER;
+                               DEFAULT_UST_PID_CHANNEL_LIVE_TIMER;
+                       extended_attr->blocking_timeout = DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT;
+                       extended_attr->monitor_timer_interval =
+                               DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER;
                        break;
                }
                break;
@@ -113,11 +131,21 @@ common_ust:
        return chan;
 
 error:
+       free(extended_attr);
        free(chan);
 error_alloc:
        return NULL;
 }
 
+void channel_attr_destroy(struct lttng_channel *channel)
+{
+       if (!channel) {
+               return;
+       }
+       free(channel->attr.extended.ptr);
+       free(channel);
+}
+
 /*
  * Disable kernel channel of the kernel session.
  */
@@ -192,6 +220,15 @@ static int channel_validate(struct lttng_channel *attr)
        return 0;
 }
 
+static int channel_validate_kernel(struct lttng_channel *attr)
+{
+       /* Kernel channels do not support blocking timeout. */
+       if (((struct lttng_channel_extended *)attr->attr.extended.ptr)->blocking_timeout) {
+               return -1;
+       }
+       return 0;
+}
+
 /*
  * Create kernel channel of the kernel session and notify kernel thread.
  */
@@ -214,9 +251,16 @@ int channel_kernel_create(struct ltt_kernel_session *ksession,
                attr = defattr;
        }
 
+       /*
+        * Set the overwrite mode for this channel based on the session
+        * type unless the client explicitly overrides the channel mode.
+        */
+       if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) {
+               attr->attr.overwrite = !!ksession->snapshot_mode;
+       }
+
+       /* Enforce mmap output for snapshot sessions. */
        if (ksession->snapshot_mode) {
-               /* Force channel attribute for snapshot mode. */
-               attr->attr.overwrite = 1;
                attr->attr.output = LTTNG_EVENT_MMAP;
        }
 
@@ -226,6 +270,11 @@ int channel_kernel_create(struct ltt_kernel_session *ksession,
                goto error;
        }
 
+       if (channel_validate_kernel(attr) < 0) {
+               ret = LTTNG_ERR_INVALID;
+               goto error;
+       }
+
        /* Channel not found, creating it */
        ret = kernel_create_channel(ksession, attr);
        if (ret < 0) {
@@ -242,7 +291,7 @@ int channel_kernel_create(struct ltt_kernel_session *ksession,
 
        ret = LTTNG_OK;
 error:
-       free(defattr);
+       channel_attr_destroy(defattr);
        return ret;
 }
 
@@ -318,9 +367,16 @@ int channel_ust_create(struct ltt_ust_session *usess,
                }
        }
 
+       /*
+        * Set the overwrite mode for this channel based on the session
+        * type unless the client explicitly overrides the channel mode.
+        */
+       if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) {
+               attr->attr.overwrite = !!usess->snapshot_mode;
+       }
+
+       /* Enforce mmap output for snapshot sessions. */
        if (usess->snapshot_mode) {
-               /* Force channel attribute for snapshot mode. */
-               attr->attr.overwrite = 1;
                attr->attr.output = LTTNG_EVENT_MMAP;
        }
 
@@ -445,7 +501,7 @@ int channel_ust_create(struct ltt_ust_session *usess,
                }
        }
 
-       free(defattr);
+       channel_attr_destroy(defattr);
        return LTTNG_OK;
 
 error_free_chan:
@@ -455,7 +511,7 @@ error_free_chan:
         */
        trace_ust_destroy_channel(uchan);
 error:
-       free(defattr);
+       channel_attr_destroy(defattr);
        return ret;
 }