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|
#!/bin/sh
# PCP QA Test No. 1705
# Exercise the bpftrace PMDA - error conditions
#
seq=`basename $0`
echo "QA output created by $seq"
. ./common.bpftrace
case `admin/whatami`
in
*openSUSE\ Leap\ 15.*)
_notrun "this test does not work on openSUSE 15.x"
;;
esac
_pmdabpftrace_check
echo "tracepoint:raw_syscalls:sys_enter" >$tmp.tmp
_pmdabpftrace_check_probes $tmp.tmp
case `hostname -s`
in
bozo-vm)
_notrun "cannot set bpftrace hz=999 on this VM"
;;
esac
status=1 # failure is the default!
_prepare_pmda bpftrace
trap "_pmdabpftrace_cleanup; exit \$status" 0 1 2 3 15
_stop_auto_restart pmcd
_filter_exit_code()
{
# some versions of bpftrace exit with different codes
sed -e 's/ value -6$/ value 1/g'
}
# names of first 512 d* kprobes are not deterministic ...
#
# bpftrace.control.register old value="{}" new value="// name: test4
# kprobe:d3cold_allowed_show { @c = count(); }
# kprobe:d3cold_allowed_store { @c = count(); }
# ...
# kprobe:debugfs_write_file_bool { @c = count(); }
# kprobe:debugfs_write_file_str { @c = count(); }"
#
_filter_kprobe()
{
$PCP_AWK_PROG '
!/^kprobe:/ { print; next }
{ print "kprobe:... { @c = count(); }"
print "..."
print "kprobe:... { @c = count(); }\""
exit
}'
}
# this shoud be the default, just to be sure, to be sure, ...
#
BPFTRACE_MAX_PROBES=512; export BPFTRACE_MAX_PROBES
# real QA test starts here
cat <<EOF | _pmdabpftrace_install
# Installed by PCP QA test $seq on `date`
[dynamic_scripts]
enabled = true
auth_enabled = false
[bpftrace]
# ridiculously small for test5 running on (potentially) slow VMs
max_throughput = 4096
EOF
echo "=== bpftrace script without variables ==="
./src/store_and_fetch bpftrace.control.register "// name: test1
tracepoint:raw_syscalls:sys_enter { }" | grep -o '"error": "no bpftrace variables or printf statements found, please include at least one variable or printf statement in your script"'
echo
echo "=== invalid probe ==="
pmstore bpftrace.control.register "// name: test2
does_not_exist { @c = count(); }"
_pmdabpftrace_wait_for_value bpftrace.scripts.test2.status '"error"'
# error message changed between bpftrace versions
pminfo -f bpftrace.scripts.test2.error >>$seq_full
pminfo -f bpftrace.scripts.test2.error \
| grep -E -q "(Invalid provider: 'does_not_exist')|(Unrecognized probe type: does_not_exist)|(Invalid probe type made it to attachpoint parser)|(Invalid probe type: does_not_exist)" \
&& echo "error message (invalid probe) found"
pminfo -f bpftrace.scripts.test2.exit_code | _filter_exit_code
echo
echo "=== syntax error ==="
pmstore bpftrace.control.register "// name: test3
tracepoint:raw_syscalls:sys_enter { @c = count(; }"
# 10sec (default) is not long enough on vm03
#
_pmdabpftrace_wait_for_value bpftrace.scripts.test3.status '"error"' 15
pminfo -f bpftrace.scripts.test3.error
pminfo -f bpftrace.scripts.test3.exit_code
echo
echo "=== too many attached tracepoints ==="
# kprobe:d* matches between 4000 and 6000 tracepoints, so more than enough
# ... pick the first 513 of 'em
#
# Note: we used to use kprobe:* here, but even though this matches
# a bazillion tracepoints, on some systems it counted as only
# 1 probe, so we never saw the 512 max exceeded; so now we're
# enumerating 513 explicit kprobes.
# Note: on vm20 (Ubuntu 20.04) this sort of tracepoint
# kprobe:dyn_constraint.isra.0
# causes bpftrace to choke at the .0 (not expecting an integer!)
# skip any tracepoints that match \.[0-9]
#
$sudo bpftrace -l "kprobe:d*" \
| sed -e '/\.[0-9]/d' \
| $PCP_AWK_PROG >$tmp.probe '
BEGIN { print "// name: test4" }
{ print $0 " { @c = count(); }" }
NR > 512 { exit }'
num_probes=`wc -l <$tmp.probe | sed -e 's/ *//g'`
num_probes=`expr $num_probes - 1`
if [ "$num_probes" -ne 513 ]
then
echo "Arrgh: expecting 513 probes, got $num_probes. See $seq.full"
echo "num_probes=$num_probes" >>$seq_full
cat $tmp.probe >>$seq_full
fi
pmstore bpftrace.control.register "`cat $tmp.probe`" 2>&1 \
| _filter_kprobe
_pmdabpftrace_wait_for_value bpftrace.scripts.test4.status '"error"' 15
# Note: Failure texts we've seen here include
# vm03 (Fedora 42)
# value "cannot attach kprobe, Invalid argument
# ERROR: Error attaching probe: kprobe:debug_registers_open"
# bozo (Ubuntu 24.04)
# value "ERROR: Can't attach to 514 probes because it exceeds the current limit of 512 probes.
# You can increase the limit through the BPFTRACE_MAX_PROBES environment variable, but BE CAREFUL since a high number of probes attached can cause your system to crash."
#
pminfo -f bpftrace.scripts.test4.error \
| tee -a $seq_full \
| sed \
-e 's/ [1-9][0-9]* / PROBES /g' \
-e 's/"ERROR: /"/' \
-e '/value "Can'"'"'t attach to PROBES probes/{
s/value ".*"*/value "<kprobes error babble>"/
n
/^You can increase the limit through/d
}' \
-e '/value "Error attaching probe: '"'"'kprobe:\*'"'"'"/{
s/value ".*"*/value "<kprobes error babble>"/
}' \
-e '/value "cannot attach kprobe, Invalid argument/{
s/value ".*"*/value "<kprobes error babble>"/
n
/^ERROR: Error attaching probe: kprobe:/d
}' \
-e '/value "create_probe_event: .* Too many open files/{
s/value ".*"*/value "<kprobes error babble>"/
n
/^ERROR: Error attaching probe: kprobe:/d
}' \
-e '/value "Unable to attach probe: kprobe:dbg_get_reg. /{
s/value ".*"/value "<kprobes error babble>"/
}'
# end
pminfo -f bpftrace.scripts.test4.exit_code \
| sed -e '/value/s/ 255$/ 1/'
echo
echo "=== too much output ==="
pmstore bpftrace.control.register '// name: test5
profile:hz:999 { printf("test"); }'
_pmdabpftrace_wait_for_value bpftrace.scripts.test5.status '"error"' 20
pminfo -f bpftrace.scripts.test5.error | sed -e 's/ [1-9][0-9]* / LIMIT /g'
echo
echo "=== duplicate script name ==="
pmstore bpftrace.control.register "// name: test6
tracepoint:raw_syscalls:sys_enter { @x = count() }"
./src/store_and_fetch bpftrace.control.register "// name: test6
tracepoint:raw_syscalls:sys_enter { @x = count() }" | grep -o '"error": "Script name .* is already in use by another script."'
echo
_pmdabpftrace_remove
status=0
exit
|
