X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=README.md;h=7b04cd83b04991153ce8f7282ef3203a24489661;hb=2b3dbafc429e1db16d1f3bc30b95b0bc92932d42;hp=17553e63346d96dbbaef254eb3de3b13ebf5e509;hpb=6bb4326c067161532e0e6f3a0deec2d28b4595e8;p=lttng-modules.git diff --git a/README.md b/README.md index 17553e63..7b04cd83 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 +95,19 @@ available from LTTng: - `CONFIG_KALLSYMS_ALL`: state dump of mapping between block device number and name +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 -----