syscall tracing: sys_getcpu

[lttng-modules.git] / README

diff --git a/README b/README
index 1a7cea16e4ca49e72ae957e1d3723edb8d746a19..1fd49b68dea49d650b394c064a4c43f73a5bbabe 100644 (file)
--- a/README
+++ b/README
@@ -1,7 +1,7 @@
 LTTng 2.0 modules
 
 Mathieu Desnoyers
-July 19, 2011
+February 8, 2012
 
 LTTng 2.0 kernel modules build against a vanilla or distribution kernel, without
 need for additional patches. Other features:
@@ -9,7 +9,7 @@ need for additional patches. Other features:
 - Produces CTF (Common Trace Format) natively,
   (http://www.efficios.com/ctf)
 - Tracepoints, Function tracer, CPU Performance Monitoring Unit (PMU)
-  counters and kprobes support,
+  counters, kprobes, and kretprobes support,
 - Integrated interface for both kernel and userspace tracing,
 - Have the ability to attach "context" information to events in the
   trace (e.g. any PMU counter, pid, ppid, tid, comm name, etc).
@@ -22,21 +22,20 @@ access to your full kernel source tree), and use:
 
 % make
 # make modules_install
+# depmod -a
 
 If you need to specify the target directory to the kernel you want to build
 against, use:
 
 % KERNELDIR=path_to_kernel_dir make
 # KERNELDIR=path_to_kernel_dir make modules_install
+# depmod -a kernel_version
 
 Use lttng-tools to control the tracer. LTTng tools should automatically load
 the kernel modules when needed. Use Babeltrace to print traces as a
 human-readable text log. These tools are available at the following URL:
 http://lttng.org/lttng2.0
 
-Please note that the LTTng-UST 2.0 (user-space tracing counterpart of LTTng 2.0)
-is still in active development and not released yet.
-
 So far, it has been tested on vanilla Linux kernels 2.6.38, 2.6.39 and 3.0 (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
@@ -47,6 +46,10 @@ 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.
 
+LTTng-modules depends on having kallsyms enabled in the kernel it is
+built against. Ideally, if you want to have system call tracing, the
+"Trace Syscalls" feature should be enabled too. 
+
 * Note about Perf PMU counters support
 
 Each PMU counter has its zero value set when it is attached to a context with