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# Test cases for probefunc() function
proc grep {fd re } {
while {[gets $fd s] >= 0} {
if [regexp $re $s] {
return $s
}
}
}
proc sleep_one_sec {} {
wait_n_secs 1;
return 0;
}
set systemtap_script {
global funcname
probe %s {
funcname = probefunc()
exit()
}
probe begin {
log("systemtap starting probe")
}
probe end {
log("systemtap ending probe")
printf("%%s\n", funcname)
}
}
# open /proc/kallsyms to get address for scheduler_tick symbol
set symf "/proc/kallsyms"
set symfd [open $symf r]
set re "\\mscheduler_tick\\M"
set rs [grep $symfd $re]
set flds [split $rs " "]
set addr [lindex $flds 0]
close $symfd
set prefix "probefunc:"
# test probefunc() with kernel.statement().absolute
set output_string "\\mscheduler_tick\\M\r\n"
set probepoint "kernel.statement(0x$addr).absolute"
set script [format $systemtap_script $probepoint]
stap_run "${prefix}.statement.(0xaddr).absolute" sleep_one_sec $output_string -g -e $script
# test probefunc() with kernel.function()
set probepoint "kernel.function(\"scheduler_tick\")"
set script [format $systemtap_script $probepoint]
stap_run $prefix$probepoint sleep_one_sec $output_string -e $script
# test probefunc() with kernel.function().inline
# NOTE probefunc inline behavior changed after 1.8.
#
# Notice we're keeping the name of the test the same
# 'probefunc:kernel.function("context_switch").inline', but broadening
# the test a bit to also include 'kernel.function("should_resched")'
# for newer kernels. Keeping the name the same helps in comparing
# results between releases.
set output_string "\\m(context_switch|should_resched)\\M\r\n"
set testname "kernel.function(\"context_switch\").inline"
set probepoint "kernel.function(\"context_switch\").inline ?, kernel.function(\"should_resched\").inline ?"
set script [format $systemtap_script $probepoint]
stap_run $prefix$testname sleep_one_sec $output_string -e $script --compatible=1.8
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