tracing: Remove markers

Now that the last users of markers have migrated to the event
tracer we can kill off the (now orphan) support code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090917173527.GA1699@lst.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 0 insertions, 104 deletions

diff --git a/Documentation/markers.txt b/Documentation/markers.txt
deleted file mode 100644
index d2b3d0e91b26..000000000000
--- a/Documentation/markers.txt
+++ /dev/null
@@ -1,104 +0,0 @@
-                     Using the Linux Kernel Markers
-
-                            Mathieu Desnoyers
-
-
-This document introduces Linux Kernel Markers and their use. It provides
-examples of how to insert markers in the kernel and connect probe functions to
-them and provides some examples of probe functions.
-
-
-* Purpose of markers
-
-A marker placed in code provides a hook to call a function (probe) that you can
-provide at runtime. A marker can be "on" (a probe is connected to it) or "off"
-(no probe is attached). When a marker is "off" it has no effect, except for
-adding a tiny time penalty (checking a condition for a branch) and space
-penalty (adding a few bytes for the function call at the end of the
-instrumented function and adds a data structure in a separate section).  When a
-marker is "on", the function you provide is called each time the marker is
-executed, in the execution context of the caller. When the function provided
-ends its execution, it returns to the caller (continuing from the marker site).
-
-You can put markers at important locations in the code. Markers are
-lightweight hooks that can pass an arbitrary number of parameters,
-described in a printk-like format string, to the attached probe function.
-
-They can be used for tracing and performance accounting.
-
-
-* Usage
-
-In order to use the macro trace_mark, you should include linux/marker.h.
-
-#include <linux/marker.h>
-
-And,
-
-trace_mark(subsystem_event, "myint %d mystring %s", someint, somestring);
-Where :
-- subsystem_event is an identifier unique to your event
-    - subsystem is the name of your subsystem.
-    - event is the name of the event to mark.
-- "myint %d mystring %s" is the formatted string for the serializer. "myint" and
-  "mystring" are repectively the field names associated with the first and
-  second parameter.
-- someint is an integer.
-- somestring is a char pointer.
-
-Connecting a function (probe) to a marker is done by providing a probe (function
-to call) for the specific marker through marker_probe_register() and can be
-activated by calling marker_arm(). Marker deactivation can be done by calling
-marker_disarm() as many times as marker_arm() has been called. Removing a probe
-is done through marker_probe_unregister(); it will disarm the probe.
-
-marker_synchronize_unregister() must be called between probe unregistration and
-the first occurrence of
-- the end of module exit function,
-  to make sure there is no caller left using the probe;
-- the free of any resource used by the probes,
-  to make sure the probes wont be accessing invalid data.
-This, and the fact that preemption is disabled around the probe call, make sure
-that probe removal and module unload are safe. See the "Probe example" section
-below for a sample probe module.
-
-The marker mechanism supports inserting multiple instances of the same marker.
-Markers can be put in inline functions, inlined static functions, and
-unrolled loops as well as regular functions.
-
-The naming scheme "subsystem_event" is suggested here as a convention intended
-to limit collisions. Marker names are global to the kernel: they are considered
-as being the same whether they are in the core kernel image or in modules.
-Conflicting format strings for markers with the same name will cause the markers
-to be detected to have a different format string not to be armed and will output
-a printk warning which identifies the inconsistency:
-
-"Format mismatch for probe probe_name (format), marker (format)"
-
-Another way to use markers is to simply define the marker without generating any
-function call to actually call into the marker. This is useful in combination
-with tracepoint probes in a scheme like this :
-
-void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk);
-
-DEFINE_MARKER_TP(marker_eventname, tracepoint_name, probe_tracepoint_name,
-        "arg1 %u pid %d");
-
-notrace void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk)
-{
-        struct marker *marker = &GET_MARKER(kernel_irq_entry);
-        /* write data to trace buffers ... */
-}
-
-* Probe / marker example
-
-See the example provided in samples/markers/src
-
-Compile them with your kernel.
-
-Run, as root :
-modprobe marker-example (insmod order is not important)
-modprobe probe-example
-cat /proc/marker-example (returns an expected error)
-rmmod marker-example probe-example
-dmesg