X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=README.md;h=fc083249cd5982b20dd1b0c9115ebda612868e72;hb=45fe4e1a42028b821757e0b98f9b33bf435a108a;hp=17553e63346d96dbbaef254eb3de3b13ebf5e509;hpb=6bb4326c067161532e0e6f3a0deec2d28b4595e8;p=lttng-modules.git diff --git a/README.md b/README.md index 17553e63..fc083249 100644 --- a/README.md +++ b/README.md @@ -66,6 +66,7 @@ Make sure your target kernel has the following config options enabled: - `CONFIG_TRACEPOINTS`: kernel tracepoint instrumentation (enabled as a side-effect of any of the perf/ftrace/blktrace instrumentation features). + - `CONFIG_KPROBES` (5.7+): use kallsyms for kernel 5.7 and newer. ### Supported (optional) kernel config options @@ -94,6 +95,34 @@ available from LTTng: - `CONFIG_KALLSYMS_ALL`: state dump of mapping between block device number and name +### LTTng specific kernel config options + +The following kernel configuration options are provided by LTTng: + + - `CONFIG_LTTNG`: Build LTTng (Defaults to 'm'). + - `CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM`: Enable the experimental bitwise + enumerations (Defaults to 'n'). This can be enabled by building with: + + make CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM=y + + - `CONFIG_LTTNG_CLOCK_PLUGIN_TEST`: Build the test clock plugin (Defaults to + 'm'). This plugin overrides the trace clock and should always be built as a + module for testing. + + +Customization/Extension +----------------------- + +The lttng-modules source includes definitions for the actual callback +functions that will be attached to the kernel tracepoints by lttng. +The lttng-modules project implements its own macros generating these +callbacks: the LTTNG_TRACEPOINT_EVENT macro family found in +instrumentation/events/lttng-module/. In order to show up in a +lttng-modules trace, a kernel tracepoint must be defined within the +kernel tree, and also defined within lttng-modules with the +LTTNG_TRACEPOINT_EVENT macro family. Customizations or extensions must +be done by modifying instances of these macros within the lttng-modules +source. Usage -----