Currently the statement block that follows an alias definition is
implicitly added as a prologue to any probe that refers to the alias.
But it seems to me that only allowing adding those statements contained
in an alias definition as a prologue makes me to lose some controls over
them.
For example, I have a tapsets:
probe addevent.tskdispatch.cpuidle
= kernel.inline("idle_balance")
{
log_cpuidle_tracedata(HOOKID_TASK_CPUIDLE, backtrace)
}
What I want is to let user specify whether to log backtrace in his
scripts, like the following:
stap -e "probe addevent.tskdispatch.cpuidle { backtrace=1 } -I LKET_TAPSETS
But unfortunately, it won't work because "backtrace=1" is added after
"log_cpuidle_tracedata(HOOKID_TASK_CPUIDLE, backtrace)". So how about
providing a way to specify whether the statements in a alias definition
could be added as prologue or epilogue to any probe that refers to that
alias?