rtla currently only sets tracer options that are explicitly set by the
user, with the exception of OSNOISE_WORKLOAD.
This leads to improper behavior in case rtla is run with those options
not set to the default value. rtla does reset them to the original
value upon exiting, but that does not protect it from starting with
non-default values set either by an improperly exited rtla or by another
user of the tracers.
For example, after running this command:
$ echo 1 > /sys/kernel/tracing/osnoise/stop_tracing_us
all runs of rtla will stop at the 1us threshold, even if not requested
by the user:
$ rtla osnoise hist
Index CPU-000 CPU-001
1 8 5
2 5 9
3 1 2
4 6 1
5 2 1
6 0 1
8 1 1
12 0 1
14 1 0
15 1 0
over: 0 0
count: 25 21
min: 1 1
avg: 3.68 3.05
max: 15 12
rtla osnoise hit stop tracing
Fix the problem by setting the default value for all tracer options if
the user has not provided their own value.
For most of the options, it's enough to just drop the if clause checking
for the value being set. For cpus, "all" is used as the default value,
and for osnoise default period and runtime, default values of
the osnoise_data variable in trace_osnoise.c are used.
Cc: Luis Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/20250320092500.101385-5-tglozar@redhat.com
Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
0122938a7a