-LTTng 2.0 modules
+LTTng 2.x modules
Mathieu Desnoyers
-April 6, 2012
+March 29, 2013
-LTTng 2.0 kernel modules build against a vanilla or distribution kernel, without
+LTTng 2.x kernel modules build against a vanilla or distribution kernel, without
need for additional patches. Other features:
- Produces CTF (Common Trace Format) natively,
human-readable text log. These tools are available at the following URL:
http://lttng.org/lttng2.0
-So far, it has been tested on vanilla Linux kernels 2.6.38, 2.6.39, 3.0,
-3.1, 3.2, 3.3 (on x86 32/64-bit, and powerpc 32-bit at the moment, build
-tested on ARM). It should work fine with newer kernels and other
-architectures, but expect build issues with kernels older than 2.6.36.
-The clock source currently used is the standard gettimeofday (slower,
-less scalable and less precise than the LTTng 0.x clocks). Support for
-LTTng 0.x clocks will be added back soon into LTTng 2.0. Please note
-that lttng-modules 2.0 can build on a Linux kernel patched with the
-LTTng 0.x patchset, but the lttng-modules 2.0 replace the lttng-modules
-0.x, so both tracers cannot be installed at the same time for a given
-kernel version.
+Linux kernels >= 2.6.36 are supported.
* Kernel config options required
+CONFIG_MODULES: required
+ * Kernel modules support.
CONFIG_KALLSYMS: required
* See wrapper/ files. This is necessary until the few required missing
symbols are exported to GPL modules from mainline.
lttng add-context -t perf:*
CONFIG_EVENT_TRACING:
needed to allow block layer tracing
-CONFIG_KPROBES:
+CONFIG_KPROBES:
Dynamic probe.
lttng enable-event -k --probe ...
CONFIG_KRETPROBES:
Dynamic function entry/return probe.
lttng enable-event -k --function ...
+CONFIG_KALLSYMS_ALL:
+ State dump of mapping between block device number and name.
* Note about Perf PMU counters support