X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=doc%2Fman%2Flttng-add-trigger.1.txt;fp=doc%2Fman%2Flttng-add-trigger.1.txt;h=d111c43b9f3f7991117ed2fec83bdf71780c81ea;hp=0b7363e8190a061930c5e0f4c07278bf289870d4;hb=473c70cacf20bda64e8bf5a298001f55edc37898;hpb=ed0a071d1ed8b289211d9b4f4c2afc5575143b13 diff --git a/doc/man/lttng-add-trigger.1.txt b/doc/man/lttng-add-trigger.1.txt index 0b7363e81..d111c43b9 100644 --- a/doc/man/lttng-add-trigger.1.txt +++ b/doc/man/lttng-add-trigger.1.txt @@ -1,6 +1,6 @@ lttng-add-trigger(1) ==================== -:revdate: 3 May 2021 +:revdate: 6 May 2021 NAME @@ -40,6 +40,8 @@ Unix user is `root`, with the man:lttng-list-triggers(1) command. Remove a trigger with the man:lttng-remove-trigger(1) command. +See the <> section below for usage examples. + [[cond-spec]] Condition specifier @@ -306,6 +308,116 @@ include::common-lttng-cmd-help-options.txt[] include::common-lttng-cmd-after-options.txt[] +[[examples]] +EXAMPLES +-------- +.Add an ``event rule matches'' trigger of which the action is to send a notification. +==== +The `event-rule-matches` trigger condition below specifies an event rule +which matches any Linux system call entry event with a name starting +with `exec`. + +[role="term"] +---- +$ lttng add-trigger --condition=event-rule-matches \ + --domain=kernel --type=syscall:entry \ + --name='exec*' --action=notify +---- +==== + +.Add an ``event rule matches'' trigger of which the action is to stop a tracing session and then rotate it. +==== +The `event-rule-matches` trigger condition below specifies an event rule +which matches any user space tracepoint event with a name starting with +`my_app:` and with a log level at least as severe as a warning. + +The order of the option:--action options below is significant. + +[role="term"] +---- +$ lttng add-trigger --condition=event-rule-matches \ + --domain=user --name='my_app:*' \ + --log-level=TRACE_WARNING.. \ + --action=stop-session my-session \ + --action=rotate-session my-session +---- + +See man:lttng-concepts(7) to learn more about tracing sessions and +rotations. +==== + +.Add an ``event rule matches'' trigger with a specific name. +==== +The `event-rule-matches` trigger condition below specifies an event rule +which matches events which LTTng creates from the `my-logger` Python +logger. + +The added trigger is named `my-trigger`, a unique name for your Unix +user. + +See the option:--name option. + +[role="term"] +---- +$ lttng add-trigger --name=my-trigger \ + --condition=event-rule-matches \ + --domain=python --name=my-logger \ + --action=snapshot-session my-session +---- +==== + +.Add an ``event rule matches'' trigger as another Unix user. +==== +The command line below adds a trigger as the `mireille` Unix user. + +Your Unix user must be `root` to use the option:--owner-uid option. + +The condition of the trigger specifies an event rule which matches LTTng +kernel tracepoint events with a name which starts with `sched`. + +[role="term"] +---- +# lttng add-trigger --owner-uid=$(id --user mireille) \ + --condition=event-rule-matches \ + --domain=kernel --name='sched*' \ + --action=notify +---- +==== + +.Add an ``event rule matches'' trigger with a notification action to be executed every 10{nbsp}times. +==== +The `event-rule-matches` trigger condition below specifies an event rule +which matches all user space tracepoint events. + +See the nloption:--rate-policy option above. + +[role="term"] +---- +$ lttng add-trigger --condition=event-rule-matches \ + --domain=user --action=notify \ + --rate-policy=every:10 +---- +==== + +.Add an ``event rule matches'' trigger with a tracing session starting action to be executed a single time after 40{nbsp}times. +==== +The `event-rule-matches` trigger condition below specifies an event rule +which matches any Linux system call event (entry and exit) of which the +`fd` event record field is less than{nbsp}3. + +See the nloption:--rate-policy option above. + +[role="term"] +---- +$ lttng add-trigger --condition=event-rule-matches \ + --domain=kernel --type=syscall \ + --filter='fd < 3' \ + --action=start-session my-session \ + --rate-policy=once-after:40 +---- +==== + + include::common-footer.txt[]