tools/bootconfig: Add a script to generates bootconfig from ftrace

Add a ftrace2bconf.sh under tools/bootconfig/scripts which generates
a bootconfig file from the current ftrace settings.

To read the ftrace settings, ftrace2bconf.sh requires the root
privilege (or sudo). The ftrace2bconf.sh will output the bootconfig
to stdout and error messages to stderr, so usually you'll run it as

 # ftrace2bconf.sh > ftrace.bconf

Note that some ftrace configurations are not supported. For example,
function-call/callgraph trace/notrace settings are not supported because
the wildcard has been expanded and lost in the ftrace anymore.

Link: https://lkml.kernel.org/r/159704852163.175360.16738029520293360558.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Masami Hiramatsu 2020-08-10 17:35:21 +09:00 committed by Steven Rostedt (VMware)
parent 7e66ef0046
commit 2b86062a34

View File

@ -0,0 +1,244 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0-only
usage() {
echo "Dump boot-time tracing bootconfig from ftrace"
echo "Usage: $0 [--debug] [ > BOOTCONFIG-FILE]"
exit 1
}
DEBUG=
while [ x"$1" != x ]; do
case "$1" in
"--debug")
DEBUG=$1;;
-*)
usage
;;
esac
shift 1
done
if [ x"$DEBUG" != x ]; then
set -x
fi
TRACEFS=`grep -m 1 -w tracefs /proc/mounts | cut -f 2 -d " "`
if [ -z "$TRACEFS" ]; then
if ! grep -wq debugfs /proc/mounts; then
echo "Error: No tracefs/debugfs was mounted."
exit 1
fi
TRACEFS=`grep -m 1 -w debugfs /proc/mounts | cut -f 2 -d " "`/tracing
if [ ! -d $TRACEFS ]; then
echo "Error: ftrace is not enabled on this kernel." 1>&2
exit 1
fi
fi
######## main #########
set -e
emit_kv() { # key =|+= value
echo "$@"
}
global_options() {
val=`cat $TRACEFS/max_graph_depth`
[ $val != 0 ] && emit_kv kernel.fgraph_max_depth = $val
if grep -qv "^#" $TRACEFS/set_graph_function $TRACEFS/set_graph_notrace ; then
cat 1>&2 << EOF
# WARN: kernel.fgraph_filters and kernel.fgraph_notrace are not supported, since the wild card expression was expanded and lost from memory.
EOF
fi
}
kprobe_event_options() {
cat $TRACEFS/kprobe_events | while read p args; do
case $p in
r*)
cat 1>&2 << EOF
# WARN: A return probe found but it is not supported by bootconfig. Skip it.
EOF
continue;;
esac
p=${p#*:}
event=${p#*/}
group=${p%/*}
if [ $group != "kprobes" ]; then
cat 1>&2 << EOF
# WARN: kprobes group name $group is changed to "kprobes" for bootconfig.
EOF
fi
emit_kv $PREFIX.event.kprobes.$event.probes += $args
done
}
synth_event_options() {
cat $TRACEFS/synthetic_events | while read event fields; do
emit_kv $PREFIX.event.synthetic.$event.fields = `echo $fields | sed "s/;/,/g"`
done
}
# Variables resolver
DEFINED_VARS=
UNRESOLVED_EVENTS=
defined_vars() { # event-dir
grep "^hist" $1/trigger | grep -o ':[a-zA-Z0-9]*='
}
referred_vars() {
grep "^hist" $1/trigger | grep -o '$[a-zA-Z0-9]*'
}
per_event_options() { # event-dir
evdir=$1
# Check the special event which has no filter and no trigger
[ ! -f $evdir/filter ] && return
if grep -q "^hist:" $evdir/trigger; then
# hist action can refer the undefined variables
__vars=`defined_vars $evdir`
for v in `referred_vars $evdir`; do
if echo $DEFINED_VARS $__vars | grep -vqw ${v#$}; then
# $v is not defined yet, defer it
UNRESOLVED_EVENTS="$UNRESOLVED_EVENTS $evdir"
return;
fi
done
DEFINED_VARS="$DEFINED_VARS "`defined_vars $evdir`
fi
grep -v "^#" $evdir/trigger | while read action active; do
emit_kv $PREFIX.event.$group.$event.actions += \'$action\'
done
# enable is not checked; this is done by set_event in the instance.
val=`cat $evdir/filter`
if [ "$val" != "none" ]; then
emit_kv $PREFIX.event.$group.$event.filter = "$val"
fi
}
retry_unresolved() {
unresolved=$UNRESOLVED_EVENTS
UNRESOLVED_EVENTS=
for evdir in $unresolved; do
event=${evdir##*/}
group=${evdir%/*}; group=${group##*/}
per_event_options $evdir
done
}
event_options() {
# PREFIX and INSTANCE must be set
if [ $PREFIX = "ftrace" ]; then
# define the dynamic events
kprobe_event_options
synth_event_options
fi
for group in `ls $INSTANCE/events/` ; do
[ ! -d $INSTANCE/events/$group ] && continue
for event in `ls $INSTANCE/events/$group/` ;do
[ ! -d $INSTANCE/events/$group/$event ] && continue
per_event_options $INSTANCE/events/$group/$event
done
done
retry=0
while [ $retry -lt 3 ]; do
retry_unresolved
retry=$((retry + 1))
done
if [ "$UNRESOLVED_EVENTS" ]; then
cat 1>&2 << EOF
! ERROR: hist triggers in $UNRESOLVED_EVENTS use some undefined variables.
EOF
fi
}
is_default_trace_option() { # option
grep -qw $1 << EOF
print-parent
nosym-offset
nosym-addr
noverbose
noraw
nohex
nobin
noblock
trace_printk
annotate
nouserstacktrace
nosym-userobj
noprintk-msg-only
context-info
nolatency-format
record-cmd
norecord-tgid
overwrite
nodisable_on_free
irq-info
markers
noevent-fork
nopause-on-trace
function-trace
nofunction-fork
nodisplay-graph
nostacktrace
notest_nop_accept
notest_nop_refuse
EOF
}
instance_options() { # [instance-name]
if [ $# -eq 0 ]; then
PREFIX="ftrace"
INSTANCE=$TRACEFS
else
PREFIX="ftrace.instance.$1"
INSTANCE=$TRACEFS/instances/$1
fi
val=
for i in `cat $INSTANCE/trace_options`; do
is_default_trace_option $i && continue
val="$val, $i"
done
[ "$val" ] && emit_kv $PREFIX.options = "${val#,}"
val="local"
for i in `cat $INSTANCE/trace_clock` ; do
[ "${i#*]}" ] && continue
i=${i%]}; val=${i#[}
done
[ $val != "local" ] && emit_kv $PREFIX.trace_clock = $val
val=`cat $INSTANCE/buffer_size_kb`
if echo $val | grep -vq "expanded" ; then
emit_kv $PREFIX.buffer_size = $val"KB"
fi
if grep -q "is allocated" $INSTANCE/snapshot ; then
emit_kv $PREFIX.alloc_snapshot
fi
val=`cat $INSTANCE/tracing_cpumask`
if [ `echo $val | sed -e s/f//g`x != x ]; then
emit_kv $PREFIX.cpumask = $val
fi
val=
for i in `cat $INSTANCE/set_event`; do
val="$val, $i"
done
[ "$val" ] && emit_kv $PREFIX.events = "${val#,}"
val=`cat $INSTANCE/current_tracer`
[ $val != nop ] && emit_kv $PREFIX.tracer = $val
if grep -qv "^#" $INSTANCE/set_ftrace_filter $INSTANCE/set_ftrace_notrace; then
cat 1>&2 << EOF
# WARN: kernel.ftrace.filters and kernel.ftrace.notrace are not supported, since the wild card expression was expanded and lost from memory.
EOF
fi
event_options
}
global_options
instance_options
for i in `ls $TRACEFS/instances` ; do
instance_options $i
done