X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=contents%2Fusing-lttng%2Fcontrolling-tracing%2Fenabling-disabling-events.md;h=e41a9336716fd4685c9183da12718c6354ad9b7c;hb=47bfcb757a0192864b56d12d775f65dc8b180aaf;hp=fd6a5cd8385b76ec5900dc008f6010c0a9ed6f0f;hpb=b80ba3062f71ca7dd34abc956e5cfe9d84d90f35;p=lttng-docs.git diff --git a/contents/using-lttng/controlling-tracing/enabling-disabling-events.md b/contents/using-lttng/controlling-tracing/enabling-disabling-events.md index fd6a5cd..e41a933 100644 --- a/contents/using-lttng/controlling-tracing/enabling-disabling-events.md +++ b/contents/using-lttng/controlling-tracing/enabling-disabling-events.md @@ -12,7 +12,8 @@ in source code/binary program, logical processor and time capturing some payload) being recorded as trace data. This specific condition is composed of: - 1. A **domain** (kernel, user space or Java Util Logging) (required). + 1. A **domain** (kernel, user space, `java.util.logging`, or log4j) + (required). 2. One or many **instrumentation points** in source code or binary program (tracepoint name, address, symbol name, function name, logger name, etc.) to be executed (required). @@ -26,10 +27,10 @@ composed of: All conditions are specified using arguments passed to the `enable-event` command of the `lttng` tool. -Condition 1 is specified using either `--kernel/-k` (kernel), -`--userspace/-u` (user space) or `--jul/-j` -(JUL). Exactly one of those -three arguments must be specified. +Condition 1 is specified using either `--kernel`/`-k` (kernel), +`--userspace`/`-u` (user space), `--jul`/`-j` +(JUL), or `--log4j`/`-l` (log4j). +Exactly one of those four arguments must be specified. Condition 2 is specified using one of: @@ -86,6 +87,21 @@ the end of the string when specifying a _tracepoint_. Make sure to use it between single quotes in your favorite shell to avoid undesired shell expansion. +System call events can be enabled individually, too: + +
+lttng enable-event -k --syscall open
+lttng enable-event -k --syscall read
+lttng enable-event -k --syscall fork,chdir,pipe
+
+ +The complete list of available system call events can be +obtained using + +
+lttng list --kernel --syscall
+
+ You can see a list of events (enabled or disabled) using
@@ -123,7 +139,7 @@ Disabling an event does not add it to some blacklist: it simply removes
 it from its channel's whitelist. This is why you cannot disable an event
 which wasn't previously enabled.
 
-A disabled event will not generate any trace data, even if all its
+A disabled event doesn't generate any trace data, even if all its
 specified conditions are met.
 
 Events may be enabled and disabled at will, either when LTTng tracers