the module exit function to make sure there is no caller left using
the probe. 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 tracepoint mechanism supports inserting multiple instances of the
same tracepoint, but a single definition must be made of a given
If the tracepoint has to be used in kernel modules, an
EXPORT_TRACEPOINT_SYMBOL_GPL() or EXPORT_TRACEPOINT_SYMBOL() can be
used to export the defined tracepoints.
-
-* Probe / tracepoint example
-
-See the example provided in samples/tracepoints
-
-Compile them with your kernel. They are built during 'make' (not
-'make modules') when CONFIG_SAMPLE_TRACEPOINTS=m.
-
-Run, as root :
-modprobe tracepoint-sample (insmod order is not important)
-modprobe tracepoint-probe-sample
-cat /proc/tracepoint-sample (returns an expected error)
-rmmod tracepoint-sample tracepoint-probe-sample
-dmesg