RV now supports nested monitors, this functionality requires a container
monitor, which has virtually no functionality besides holding other
monitors, and nested monitors, that have a container as parent.
Add the -p flag to pass a parent to a monitor, this sets it up while
registering the monitor and adds necessary includes and configurations.
Add the -c flag to create a container, since containers are empty, we
don't allow supplying a dot model or a monitor type, the template is
also different since functions to enable and disable the monitor are not
defined, nor any tracepoint. The generated header file only allows to
include the rv_monitor structure in children monitors.
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/20250305140406.350227-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
dot2k suggests a list of changes to the kernel tree while adding a
monitor: edit tracepoints header, Makefile, Kconfig and moving the
monitor folder. Those changes can be easily run automatically.
Add a flag to dot2k to alter the kernel source.
The kernel source directory can be either assumed from the PWD, or from
the running kernel, if installed.
This feature works best if the kernel tree is a git repository, so that
its easier to make sure there are no unintended changes.
The main RV files (e.g. Makefile) have now a comment placeholder that
can be useful for manual editing (e.g. to know where to add new
monitors) and it is used by the script to append the required lines.
We also slightly adapt the file handling functions in dot2k: __open_file
is now called __read_file and also closes the file before returning the
content; __create_file is now a more general __write_file, we no longer
return on FileExistsError (not thrown while opening), a new
__create_file simply calls __write_file specifying the monitor folder in
the path.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20241227144752.362911-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This patch reduces and simplifies the manual steps still needed in
creating a new RV monitor.
It extends the dot2k script to create a tracepoint snippet and a
Kconfig file for the newly generated monitor. Those files can be kept
in the monitor's directory but shall be included in the main tracepoint
header and Kconfig.
Together with the checklist, dot2k now suggests the lines to add to
those files for inclusion and the Makefile line to compile the new
monitor:
Writing the monitor into the directory monitor_name
Almost done, checklist
- Edit the monitor_name/monitor_name.c to add the instrumentation
- Edit kernel/trace/rv/rv_trace.h:
Add this line where other tracepoints are included and DA_MON_EVENTS_ID is defined:
#include <monitors/monitor_name/monitor_name_trace.h>
- Edit kernel/trace/rv/Makefile:
Add this line where other monitors are included:
obj-$(CONFIG_RV_MON_MONITOR_NAME) += monitors/monitor_name/monitor_name.o
- Edit kernel/trace/rv/Kconfig:
Add this line where other monitors are included:
source "kernel/trace/rv/monitors/monitor_name/Kconfig"
- Move monitor_name/ to the kernel's monitor directory (kernel/trace/rv/monitors)
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20241227144752.362911-7-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
