/usr/sbin/killsnoop-perf is in perf-tools-unstable 0.0.1~20160212+git0c13e83-2.
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#
# killsnoop - trace kill() syscalls with signal/process details.
# Written using Linux ftrace.
#
# This traces kill() syscalls, showing which process killed which pid and
# returns the returncode (0 for success, -1 for error).
#
# This implementation is designed to work on older kernel versions, and without
# kernel debuginfo. It works by dynamic tracing of the return value of kill()
# and associating it with the previous kill() syscall return.
# This approach is kernel version specific, and may not work on your version.
# It is a workaround, and proof of concept for ftrace, until more kernel tracing
# functionality is available.
#
# USAGE: ./killsnoop [-hst] [-d secs] [-p pid] [-n name]
#
# Run "killsnoop -h" for full usage.
#
# REQUIREMENTS: FTRACE and KPROBE CONFIG, syscalls:sys_enter_kill and
# syscalls:sys_exit_kill kernel tracepoints (you may already have these
# on recent kernels) and awk.
#
# From perf-tools: https://github.com/brendangregg/perf-tools
#
# See the killsnoop(8) man page (in perf-tools) for more info.
#
# COPYRIGHT: Copyright (c) 2014 Brendan Gregg.
# COPYRIGHT: Copyright (c) 2014 Martin Probst.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
# (http://www.gnu.org/copyleft/gpl.html)
#
# 20-Jul-2014 Brendan Gregg Templated this.
# 13-Sep-2014 Martin Probst Created this.
### default variables
tracing=/sys/kernel/debug/tracing
flock=/var/tmp/.ftrace-lock; wroteflock=0
opt_duration=0; duration=; opt_name=0; name=; opt_pid=0; pid=; ftext=
opt_time=0; opt_fail=0; opt_file=0; file=
kevent_entry=events/syscalls/sys_enter_kill
kevent_return=events/syscalls/sys_exit_kill
trap ':' INT QUIT TERM PIPE HUP # sends execution to end tracing section
function usage {
cat <<-END >&2
USAGE: killsnoop [-hst] [-d secs] [-p PID] [-n name] [filename]
-d seconds # trace duration, and use buffers
-n name # process name to match
-p PID # PID to match on kill issue
-t # include time (seconds)
-s # human readable signal names
-h # this usage message
eg,
killsnoop # watch kill()s live (unbuffered)
killsnoop -d 1 # trace 1 sec (buffered)
killsnoop -p 181 # trace kill()s issued to PID 181 only
See the man page and example file for more info.
END
exit
}
function warn {
if ! eval "$@"; then
echo >&2 "WARNING: command failed \"$@\""
fi
}
function end {
# disable tracing
echo 2>/dev/null
echo "Ending tracing..." 2>/dev/null
cd $tracing
warn "echo 0 > $kevent_entry/enable"
warn "echo 0 > $kevent_return/enable"
warn "echo > trace"
(( wroteflock )) && warn "rm $flock"
}
function die {
echo >&2 "$@"
exit 1
}
function edie {
# die with a quiet end()
echo >&2 "$@"
exec >/dev/null 2>&1
end
exit 1
}
### process options
while getopts d:hn:p:st opt
do
case $opt in
d) opt_duration=1; duration=$OPTARG ;;
n) opt_name=1; name=$OPTARG ;;
p) opt_pid=1; pid=$OPTARG ;;
t) opt_time=1 ;;
s) opt_fancy=1 ;;
h|?) usage ;;
esac
done
shift $(( $OPTIND - 1 ))
(( $# )) && usage
### option logic
(( opt_pid && opt_name )) && die "ERROR: use either -p or -n."
(( opt_pid )) && ftext=" issued to PID $pid"
(( opt_name )) && ftext=" issued by process name \"$name\""
if (( opt_duration )); then
echo "Tracing kill()s$ftext for $duration seconds (buffered)..."
else
echo "Tracing kill()s$ftext. Ctrl-C to end."
fi
### select awk
# workaround for mawk fflush()
[[ -x /usr/bin/mawk ]] && awk="mawk" && mawk -W interactive && \
[ $? -eq 0 ] && awk="mawk -W interactive"
# workaround for gawk strtonum()
[[ -x /usr/bin/gawk ]] && awk="gawk --non-decimal-data"
### check permissions
cd $tracing || die "ERROR: accessing tracing. Root user? Kernel has FTRACE?
debugfs mounted? (mount -t debugfs debugfs /sys/kernel/debug)"
### ftrace lock
[[ -e $flock ]] && die "ERROR: ftrace may be in use by PID $(cat $flock) $flock"
echo $$ > $flock || die "ERROR: unable to write $flock."
wroteflock=1
### setup and begin tracing
echo nop > current_tracer
if ! echo 1 > $kevent_entry/enable; then
edie "ERROR: enabling kill() entry tracepoint Exiting."
fi
if ! echo 1 > $kevent_return/enable; then
edie "ERROR: enabling kill() return tracepoint. Exiting."
fi
(( opt_time )) && printf "%-16s " "TIMEs"
printf "%-16.16s %-6s %-8s %-10s %4s\n" "COMM" "PID" "TPID" "SIGNAL" "RETURN"
#
# Determine output format. It may be one of the following (newest first):
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# TASK-PID CPU# TIMESTAMP FUNCTION
# To differentiate between them, the number of header fields is counted,
# and an offset set, to skip the extra column when needed.
#
offset=$($awk 'BEGIN { o = 0; }
$1 == "#" && $2 ~ /TASK/ && NF == 6 { o = 1; }
$2 ~ /TASK/ { print o; exit }' trace)
### print trace buffer
warn "echo > trace"
( if (( opt_duration )); then
# wait then dump buffer
sleep $duration
cat trace
else
# print buffer live
cat trace_pipe
fi ) | $awk -v o=$offset -v opt_name=$opt_name -v name=$name \
-v opt_duration=$opt_duration -v opt_time=$opt_time \
-v opt_pid=$pid -v opt_fancy=$opt_fancy '
# fancy signal names
BEGIN {
signals[1] = "SIGHUP"
signals[2] = "SIGINT"
signals[3] = "SIGQUIT"
signals[4] = "SIGILL"
signals[6] = "SIGABRT"
signals[8] = "SIGFPE"
signals[9] = "SIGKILL"
signals[11] = "SIGSEGV"
signals[13] = "SIGPIPE"
signals[14] = "SIGALRM"
signals[15] = "SIGTERM"
signals[10] = "SIGUSR1"
signals[12] = "SIGUSR2"
signals[17] = "SIGCHLD"
signals[18] = "SIGCONT"
signals[19] = "SIGSTOP"
signals[20] = "SIGTSTP"
signals[21] = "SIGTTIN"
signals[22] = "SIGTTOU"
}
# common fields
$1 != "#" {
# task name can contain dashes
comm = pid = $1
sub(/-[0-9][0-9]*/, "", comm)
if (opt_name && match(comm, name) == 0)
next
sub(/.*-/, "", pid)
}
# sys_kill() entry
$1 != "#" && $(4+o) ~ /sys_kill/ && $(5+o) !~ /->/ {
#
# eg: ... sys_kill(pid:...
#
kpid = $(5+o)
signal = $(7+o)
sub(/,$/, "", kpid)
sub(/\)$/, "", signal)
kpid = int("0x"kpid)
signal = int("0x"signal)
current[pid,"kpid"] = kpid
current[pid,"signal"] = signal
}
# sys_kill exit
$1 != "#" && $(5+o) ~ /->/ {
rv = int($NF)
killed_pid = current[pid,"kpid"]
signal = current[pid,"signal"]
delete current[pid,"kpid"]
delete current[pid,"signal"]
if(opt_pid && killed_pid != opt_pid) {
next
}
if (opt_time) {
time = $(3+o); sub(":", "", time)
printf "%-16s ", time
}
if (opt_fancy) {
if (signals[signal] != "") {
signal = signals[signal]
}
}
printf "%-16.16s %-6s %-8s %-10s %-4s\n", comm, pid, killed_pid, signal,
rv
}
$0 ~ /LOST.*EVENTS/ { print "WARNING: " $0 > "/dev/stderr" }
'
### end tracing
end
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