#!/bin/bash # SPDX-License-Identifier: GPL-2.0+ # # Run a series of tests under KVM. By default, this series is specified # by the relevant CFLIST file, but can be overridden by the --configs # command-line argument. # # Usage: kvm.sh [ options ] # # Copyright (C) IBM Corporation, 2011 # # Authors: Paul E. McKenney scriptname=$0 args="$*" T=${TMPDIR-/tmp}/kvm.sh.$$ trap 'rm -rf $T' 0 mkdir $T cd `dirname $scriptname`/../../../../../ # This script knows only English. LANG=en_US.UTF-8; export LANG dur=$((30*60)) dryrun="" RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE PATH=${RCUTORTURE}/bin:$PATH; export PATH . functions.sh TORTURE_ALLOTED_CPUS="`identify_qemu_vcpus`" TORTURE_DEFCONFIG=defconfig TORTURE_BOOT_IMAGE="" TORTURE_BUILDONLY= TORTURE_INITRD="$RCUTORTURE/initrd"; export TORTURE_INITRD TORTURE_KCONFIG_ARG="" TORTURE_KCONFIG_GDB_ARG="" TORTURE_BOOT_GDB_ARG="" TORTURE_QEMU_GDB_ARG="" TORTURE_JITTER_START="" TORTURE_JITTER_STOP="" TORTURE_KCONFIG_KASAN_ARG="" TORTURE_KCONFIG_KCSAN_ARG="" TORTURE_KMAKE_ARG="" TORTURE_QEMU_MEM=512 torture_qemu_mem_default=1 TORTURE_REMOTE= TORTURE_SHUTDOWN_GRACE=180 TORTURE_SUITE=rcu TORTURE_MOD=rcutorture TORTURE_TRUST_MAKE="" resdir="" configs="" cpus=0 ds=`date +%Y.%m.%d-%H.%M.%S` jitter="-1" startdate="`date`" starttime="`get_starttime`" usage () { echo "Usage: $scriptname optional arguments:" echo " --allcpus" echo " --bootargs kernel-boot-arguments" echo " --bootimage relative-path-to-kernel-boot-image" echo " --buildonly" echo " --configs \"config-file list w/ repeat factor (3*TINY01)\"" echo " --cpus N" echo " --datestamp string" echo " --defconfig string" echo " --dryrun batches|scenarios|sched|script" echo " --duration minutes | s | h | d" echo " --gdb" echo " --help" echo " --interactive" echo " --jitter N [ maxsleep (us) [ maxspin (us) ] ]" echo " --kasan" echo " --kconfig Kconfig-options" echo " --kcsan" echo " --kmake-arg kernel-make-arguments" echo " --mac nn:nn:nn:nn:nn:nn" echo " --memory megabytes|nnnG" echo " --no-initrd" echo " --qemu-args qemu-arguments" echo " --qemu-cmd qemu-system-..." echo " --remote" echo " --results absolute-pathname" echo " --shutdown-grace seconds" echo " --torture lock|rcu|rcuscale|refscale|scf|X*" echo " --trust-make" exit 1 } while test $# -gt 0 do case "$1" in --allcpus) cpus=$TORTURE_ALLOTED_CPUS max_cpus=$TORTURE_ALLOTED_CPUS ;; --bootargs|--bootarg) checkarg --bootargs "(list of kernel boot arguments)" "$#" "$2" '.*' '^--' TORTURE_BOOTARGS="$TORTURE_BOOTARGS $2" shift ;; --bootimage) checkarg --bootimage "(relative path to kernel boot image)" "$#" "$2" '[a-zA-Z0-9][a-zA-Z0-9_]*' '^--' TORTURE_BOOT_IMAGE="$2" shift ;; --buildonly|--build-only) TORTURE_BUILDONLY=1 ;; --configs|--config) checkarg --configs "(list of config files)" "$#" "$2" '^[^/.a-z]\+$' '^--' configs="$configs $2" shift ;; --cpus) checkarg --cpus "(number)" "$#" "$2" '^[0-9]*$' '^--' cpus=$2 TORTURE_ALLOTED_CPUS="$2" if test -z "$TORTURE_REMOTE" then max_cpus="`identify_qemu_vcpus`" if test "$TORTURE_ALLOTED_CPUS" -gt "$max_cpus" then TORTURE_ALLOTED_CPUS=$max_cpus fi fi shift ;; --datestamp) checkarg --datestamp "(relative pathname)" "$#" "$2" '^[a-zA-Z0-9._/-]*$' '^--' ds=$2 shift ;; --defconfig) checkarg --defconfig "defconfigtype" "$#" "$2" '^[^/][^/]*$' '^--' TORTURE_DEFCONFIG=$2 shift ;; --dryrun) checkarg --dryrun "batches|sched|script" $# "$2" 'batches\|scenarios\|sched\|script' '^--' dryrun=$2 shift ;; --duration) checkarg --duration "(minutes)" $# "$2" '^[0-9][0-9]*\(s\|m\|h\|d\|\)$' '^error' mult=60 if echo "$2" | grep -q 's$' then mult=1 elif echo "$2" | grep -q 'h$' then mult=3600 elif echo "$2" | grep -q 'd$' then mult=86400 fi ts=`echo $2 | sed -e 's/[smhd]$//'` dur=$(($ts*mult)) shift ;; --gdb) TORTURE_KCONFIG_GDB_ARG="CONFIG_DEBUG_INFO=y"; export TORTURE_KCONFIG_GDB_ARG TORTURE_BOOT_GDB_ARG="nokaslr"; export TORTURE_BOOT_GDB_ARG TORTURE_QEMU_GDB_ARG="-s -S"; export TORTURE_QEMU_GDB_ARG ;; --help|-h) usage ;; --interactive) TORTURE_QEMU_INTERACTIVE=1; export TORTURE_QEMU_INTERACTIVE ;; --jitter) checkarg --jitter "(# threads [ sleep [ spin ] ])" $# "$2" '^-\{,1\}[0-9]\+\( \+[0-9]\+\)\{,2\} *$' '^error$' jitter="$2" shift ;; --kasan) TORTURE_KCONFIG_KASAN_ARG="CONFIG_DEBUG_INFO=y CONFIG_KASAN=y"; export TORTURE_KCONFIG_KASAN_ARG if test -n "$torture_qemu_mem_default" then TORTURE_QEMU_MEM=2G fi ;; --kconfig|--kconfigs) checkarg --kconfig "(Kconfig options)" $# "$2" '^CONFIG_[A-Z0-9_]\+=\([ynm]\|[0-9]\+\)\( CONFIG_[A-Z0-9_]\+=\([ynm]\|[0-9]\+\)\)*$' '^error$' TORTURE_KCONFIG_ARG="`echo "$TORTURE_KCONFIG_ARG $2" | sed -e 's/^ *//' -e 's/ *$//'`" shift ;; --kcsan) TORTURE_KCONFIG_KCSAN_ARG="CONFIG_DEBUG_INFO=y CONFIG_KCSAN=y CONFIG_KCSAN_STRICT=y CONFIG_KCSAN_REPORT_ONCE_IN_MS=100000 CONFIG_KCSAN_VERBOSE=y CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y"; export TORTURE_KCONFIG_KCSAN_ARG ;; --kmake-arg|--kmake-args) checkarg --kmake-arg "(kernel make arguments)" $# "$2" '.*' '^error$' TORTURE_KMAKE_ARG="`echo "$TORTURE_KMAKE_ARG $2" | sed -e 's/^ *//' -e 's/ *$//'`" shift ;; --mac) checkarg --mac "(MAC address)" $# "$2" '^\([0-9a-fA-F]\{2\}:\)\{5\}[0-9a-fA-F]\{2\}$' error TORTURE_QEMU_MAC=$2 shift ;; --memory) checkarg --memory "(memory size)" $# "$2" '^[0-9]\+[MG]\?$' error TORTURE_QEMU_MEM=$2 torture_qemu_mem_default= shift ;; --no-initrd) TORTURE_INITRD=""; export TORTURE_INITRD ;; --qemu-args|--qemu-arg) checkarg --qemu-args "(qemu arguments)" $# "$2" '^-' '^error' TORTURE_QEMU_ARG="`echo "$TORTURE_QEMU_ARG $2" | sed -e 's/^ *//' -e 's/ *$//'`" shift ;; --qemu-cmd) checkarg --qemu-cmd "(qemu-system-...)" $# "$2" 'qemu-system-' '^--' TORTURE_QEMU_CMD="$2" shift ;; --remote) TORTURE_REMOTE=1 ;; --results) checkarg --results "(absolute pathname)" "$#" "$2" '^/' '^error' resdir=$2 shift ;; --shutdown-grace) checkarg --shutdown-grace "(seconds)" "$#" "$2" '^[0-9]*$' '^error' TORTURE_SHUTDOWN_GRACE=$2 shift ;; --torture) checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\|rcuscale\|refscale\|scf\|X.*\)$' '^--' TORTURE_SUITE=$2 TORTURE_MOD="`echo $TORTURE_SUITE | sed -e 's/^\(lock\|rcu\|scf\)$/\1torture/'`" shift if test "$TORTURE_SUITE" = rcuscale || test "$TORTURE_SUITE" = refscale then # If you really want jitter for refscale or # rcuscale, specify it after specifying the rcuscale # or the refscale. (But why jitter in these cases?) jitter=0 fi ;; --trust-make) TORTURE_TRUST_MAKE="y" ;; *) echo Unknown argument $1 usage ;; esac shift done if test -n "$dryrun" || test -z "$TORTURE_INITRD" || tools/testing/selftests/rcutorture/bin/mkinitrd.sh then : else echo No initrd and unable to create one, aborting test >&2 exit 1 fi CONFIGFRAG=${RCUTORTURE}/configs/${TORTURE_SUITE}; export CONFIGFRAG defaultconfigs="`tr '\012' ' ' < $CONFIGFRAG/CFLIST`" if test -z "$configs" then configs=$defaultconfigs fi if test -z "$resdir" then resdir=$RCUTORTURE/res fi # Create a file of test-name/#cpus pairs, sorted by decreasing #cpus. configs_derep= for CF in $configs do case $CF in [0-9]\**|[0-9][0-9]\**|[0-9][0-9][0-9]\**|[0-9][0-9][0-9][0-9]\**) config_reps=`echo $CF | sed -e 's/\*.*$//'` CF1=`echo $CF | sed -e 's/^[^*]*\*//'` ;; *) config_reps=1 CF1=$CF ;; esac for ((cur_rep=0;cur_rep<$config_reps;cur_rep++)) do configs_derep="$configs_derep $CF1" done done touch $T/cfgcpu configs_derep="`echo $configs_derep | sed -e "s/\/$defaultconfigs/g"`" if test -n "$TORTURE_KCONFIG_GDB_ARG" then if test "`echo $configs_derep | wc -w`" -gt 1 then echo "The --config list is: $configs_derep." echo "Only one --config permitted with --gdb, terminating." exit 1 fi fi echo 'BEGIN {' > $T/cfgcpu.awk for CF1 in `echo $configs_derep | tr -s ' ' '\012' | sort -u` do if test -f "$CONFIGFRAG/$CF1" then if echo "$TORTURE_KCONFIG_ARG" | grep -q '\ $T/KCONFIG_ARG cpu_count=`configNR_CPUS.sh $T/KCONFIG_ARG` else cpu_count=`configNR_CPUS.sh $CONFIGFRAG/$CF1` fi cpu_count=`configfrag_boot_cpus "$TORTURE_BOOTARGS" "$CONFIGFRAG/$CF1" "$cpu_count"` cpu_count=`configfrag_boot_maxcpus "$TORTURE_BOOTARGS" "$CONFIGFRAG/$CF1" "$cpu_count"` echo 'scenariocpu["'"$CF1"'"] = '"$cpu_count"';' >> $T/cfgcpu.awk else echo "The --configs file $CF1 does not exist, terminating." exit 1 fi done cat << '___EOF___' >> $T/cfgcpu.awk } { for (i = 1; i <= NF; i++) print $i, scenariocpu[$i]; } ___EOF___ echo $configs_derep | awk -f $T/cfgcpu.awk > $T/cfgcpu sort -k2nr $T/cfgcpu -T="$T" > $T/cfgcpu.sort # Use a greedy bin-packing algorithm, sorting the list accordingly. awk < $T/cfgcpu.sort > $T/cfgcpu.pack -v ncpus=$cpus ' BEGIN { njobs = 0; } { # Read file of tests and corresponding required numbers of CPUs. cf[njobs] = $1; cpus[njobs] = $2; njobs++; } END { batch = 0; nc = -1; # Each pass through the following loop creates on test batch that # can be executed concurrently given ncpus. Note that a given test # that requires more than the available CPUs will run in its own # batch. Such tests just have to make do with what is available. while (nc != ncpus) { batch++; nc = ncpus; # Each pass through the following loop considers one # test for inclusion in the current batch. for (i = 0; i < njobs; i++) { if (done[i]) continue; # Already part of a batch. if (nc >= cpus[i] || nc == ncpus) { # This test fits into the current batch. done[i] = batch; nc -= cpus[i]; if (nc <= 0) break; # Too-big test in its own batch. } } } # Dump out the tests in batch order. for (b = 1; b <= batch; b++) for (i = 0; i < njobs; i++) if (done[i] == b) print cf[i], cpus[i]; }' # Generate a script to execute the tests in appropriate batches. cat << ___EOF___ > $T/script CONFIGFRAG="$CONFIGFRAG"; export CONFIGFRAG RCUTORTURE="$RCUTORTURE"; export RCUTORTURE PATH="$PATH"; export PATH TORTURE_ALLOTED_CPUS="$TORTURE_ALLOTED_CPUS"; export TORTURE_ALLOTED_CPUS TORTURE_BOOT_IMAGE="$TORTURE_BOOT_IMAGE"; export TORTURE_BOOT_IMAGE TORTURE_BUILDONLY="$TORTURE_BUILDONLY"; export TORTURE_BUILDONLY TORTURE_DEFCONFIG="$TORTURE_DEFCONFIG"; export TORTURE_DEFCONFIG TORTURE_INITRD="$TORTURE_INITRD"; export TORTURE_INITRD TORTURE_KCONFIG_ARG="$TORTURE_KCONFIG_ARG"; export TORTURE_KCONFIG_ARG TORTURE_KCONFIG_GDB_ARG="$TORTURE_KCONFIG_GDB_ARG"; export TORTURE_KCONFIG_GDB_ARG TORTURE_BOOT_GDB_ARG="$TORTURE_BOOT_GDB_ARG"; export TORTURE_BOOT_GDB_ARG TORTURE_QEMU_GDB_ARG="$TORTURE_QEMU_GDB_ARG"; export TORTURE_QEMU_GDB_ARG TORTURE_KCONFIG_KASAN_ARG="$TORTURE_KCONFIG_KASAN_ARG"; export TORTURE_KCONFIG_KASAN_ARG TORTURE_KCONFIG_KCSAN_ARG="$TORTURE_KCONFIG_KCSAN_ARG"; export TORTURE_KCONFIG_KCSAN_ARG TORTURE_KMAKE_ARG="$TORTURE_KMAKE_ARG"; export TORTURE_KMAKE_ARG TORTURE_MOD="$TORTURE_MOD"; export TORTURE_MOD TORTURE_QEMU_CMD="$TORTURE_QEMU_CMD"; export TORTURE_QEMU_CMD TORTURE_QEMU_INTERACTIVE="$TORTURE_QEMU_INTERACTIVE"; export TORTURE_QEMU_INTERACTIVE TORTURE_QEMU_MAC="$TORTURE_QEMU_MAC"; export TORTURE_QEMU_MAC TORTURE_QEMU_MEM="$TORTURE_QEMU_MEM"; export TORTURE_QEMU_MEM TORTURE_SHUTDOWN_GRACE="$TORTURE_SHUTDOWN_GRACE"; export TORTURE_SHUTDOWN_GRACE TORTURE_SUITE="$TORTURE_SUITE"; export TORTURE_SUITE TORTURE_TRUST_MAKE="$TORTURE_TRUST_MAKE"; export TORTURE_TRUST_MAKE if ! test -e $resdir then mkdir -p "$resdir" || : fi mkdir -p $resdir/$ds TORTURE_RESDIR="$resdir/$ds"; export TORTURE_RESDIR TORTURE_STOPFILE="$resdir/$ds/STOP.1"; export TORTURE_STOPFILE echo Results directory: $resdir/$ds echo $scriptname $args touch $resdir/$ds/log echo $scriptname $args >> $resdir/$ds/log echo ${TORTURE_SUITE} > $resdir/$ds/torture_suite echo Build directory: `pwd` > $resdir/$ds/testid.txt if test -d .git then echo Current commit: `git rev-parse HEAD` >> $resdir/$ds/testid.txt echo >> $resdir/$ds/testid.txt echo ' ---' Output of "'"git status"'": >> $resdir/$ds/testid.txt git status >> $resdir/$ds/testid.txt echo >> $resdir/$ds/testid.txt echo >> $resdir/$ds/testid.txt echo ' ---' Output of "'"git diff HEAD"'": >> $resdir/$ds/testid.txt git diff HEAD >> $resdir/$ds/testid.txt fi ___EOF___ kvm-assign-cpus.sh /sys/devices/system/node > $T/cpuarray.awk kvm-get-cpus-script.sh $T/cpuarray.awk $T/dumpbatches.awk cat << '___EOF___' >> $T/dumpbatches.awk BEGIN { i = 0; } { cf[i] = $1; cpus[i] = $2; i++; } # Dump out the scripting required to run one test batch. function dump(first, pastlast, batchnum, affinitylist) { print "echo ----Start batch " batchnum ": `date` | tee -a " rd "log"; print "needqemurun=" jn=1 njitter = 0; split(jitter, ja); if (ja[1] == -1 && ncpus == 0) njitter = 1; else if (ja[1] == -1) njitter = ncpus; else njitter = ja[1]; print "TORTURE_JITTER_START=\". jitterstart.sh " njitter " " rd " " dur " " ja[2] " " ja[3] "\"; export TORTURE_JITTER_START"; print "TORTURE_JITTER_STOP=\". jitterstop.sh " rd " \"; export TORTURE_JITTER_STOP" for (j = first; j < pastlast; j++) { cpusr[jn] = cpus[j]; if (cfrep[cf[j]] == "") { cfr[jn] = cf[j]; cfrep[cf[j]] = 1; } else { cfrep[cf[j]]++; cfr[jn] = cf[j] "." cfrep[cf[j]]; } builddir=rd cfr[jn] "/build"; if (cpusr[jn] > ncpus && ncpus != 0) ovf = "-ovf"; else ovf = ""; print "echo ", cfr[jn], cpusr[jn] ovf ": Starting build. `date` | tee -a " rd "log"; print "mkdir " rd cfr[jn] " || :"; print "touch " builddir ".wait"; affinitylist = ""; if (gotcpus()) { affinitylist = nextcpus(cpusr[jn]); } if (affinitylist ~ /^[0-9,-][0-9,-]*$/) print "export TORTURE_AFFINITY=" affinitylist; else print "export TORTURE_AFFINITY="; print "kvm-test-1-run.sh " CONFIGDIR cf[j], rd cfr[jn], dur " \"" TORTURE_QEMU_ARG "\" \"" TORTURE_BOOTARGS "\" > " rd cfr[jn] "/kvm-test-1-run.sh.out 2>&1 &" print "echo ", cfr[jn], cpusr[jn] ovf ": Waiting for build to complete. `date` | tee -a " rd "log"; print "while test -f " builddir ".wait" print "do" print "\tsleep 1" print "done" print "echo ", cfr[jn], cpusr[jn] ovf ": Build complete. `date` | tee -a " rd "log"; jn++; } print "runfiles=" for (j = 1; j < jn; j++) { builddir=rd cfr[j] "/build"; if (TORTURE_BUILDONLY) print "rm -f " builddir ".ready" else print "mv " builddir ".ready " builddir ".run" print "runfiles=\"$runfiles " builddir ".run\"" fi print "if test -f \"" rd cfr[j] "/builtkernel\"" print "then" print "\techo ----", cfr[j], cpusr[j] ovf ": Kernel present. `date` | tee -a " rd "log"; print "\tneedqemurun=1" print "fi" } if (TORTURE_BUILDONLY && njitter != 0) { njitter = 0; print "echo Build-only run, so suppressing jitter | tee -a " rd "log" } if (TORTURE_BUILDONLY) { print "needqemurun=" } print "if test -n \"$needqemurun\"" print "then" print "\techo ---- Starting kernels. `date` | tee -a " rd "log"; print "\t$TORTURE_JITTER_START"; print "\twhile ls $runfiles > /dev/null 2>&1" print "\tdo" print "\t\t:" print "\tdone" print "\t$TORTURE_JITTER_STOP"; print "\techo ---- All kernel runs complete. `date` | tee -a " rd "log"; print "else" print "\twait" print "\techo ---- No kernel runs. `date` | tee -a " rd "log"; print "fi" for (j = 1; j < jn; j++) { print "echo ----", cfr[j], cpusr[j] ovf ": Build/run results: | tee -a " rd "log"; print "cat " rd cfr[j] "/kvm-test-1-run.sh.out | tee -a " rd "log"; } } END { njobs = i; nc = ncpus; first = 0; batchnum = 1; # Each pass through the following loop considers one test. for (i = 0; i < njobs; i++) { if (ncpus == 0) { # Sequential test specified, each test its own batch. dump(i, i + 1, batchnum); first = i; batchnum++; } else if (nc < cpus[i] && i != 0) { # Out of CPUs, dump out a batch. dump(first, i, batchnum); first = i; nc = ncpus; batchnum++; } # Account for the CPUs needed by the current test. nc -= cpus[i]; } # Dump the last batch. if (ncpus != 0) dump(first, i, batchnum); } ___EOF___ awk < $T/cfgcpu.pack \ -v TORTURE_BUILDONLY="$TORTURE_BUILDONLY" \ -v CONFIGDIR="$CONFIGFRAG/" \ -v RCUTORTURE="$RCUTORTURE" \ -v ncpus=$cpus \ -v jitter="$jitter" \ -v rd=$resdir/$ds/ \ -v dur=$dur \ -v TORTURE_QEMU_ARG="$TORTURE_QEMU_ARG" \ -v TORTURE_BOOTARGS="$TORTURE_BOOTARGS" \ -f $T/dumpbatches.awk >> $T/script echo kvm-end-run-stats.sh "$resdir/$ds" "$starttime" >> $T/script # Extract the tests and their batches from the script. egrep 'Start batch|Starting build\.' $T/script | grep -v ">>" | sed -e 's/:.*$//' -e 's/^echo //' -e 's/-ovf//' | awk ' /^----Start/ { batchno = $3; next; } { print batchno, $1, $2 }' > $T/batches # As above, but one line per batch. grep -v '^#' $T/batches | awk ' BEGIN { oldbatch = 1; } { if (oldbatch != $1) { print ++n ". " curbatch; curbatch = ""; oldbatch = $1; } curbatch = curbatch " " $2; } END { print ++n ". " curbatch; }' > $T/scenarios if test "$dryrun" = script then cat $T/script exit 0 elif test "$dryrun" = sched then # Extract the test run schedule from the script. egrep 'Start batch|Starting build\.' $T/script | grep -v ">>" | sed -e 's/:.*$//' -e 's/^echo //' nbuilds="`grep 'Starting build\.' $T/script | grep -v ">>" | sed -e 's/:.*$//' -e 's/^echo //' | awk '{ print $1 }' | grep -v '\.' | wc -l`" echo Total number of builds: $nbuilds nbatches="`grep 'Start batch' $T/script | grep -v ">>" | wc -l`" echo Total number of batches: $nbatches exit 0 elif test "$dryrun" = batches then cat $T/batches exit 0 elif test "$dryrun" = scenarios then cat $T/scenarios exit 0 else # Not a dryrun. Record the batches and the number of CPUs, then run the script. bash $T/script ret=$? cp $T/batches $resdir/$ds/batches cp $T/scenarios $resdir/$ds/scenarios echo '#' cpus=$cpus >> $resdir/$ds/batches exit $ret fi # Tracing: trace_event=rcu:rcu_grace_period,rcu:rcu_future_grace_period,rcu:rcu_grace_period_init,rcu:rcu_nocb_wake,rcu:rcu_preempt_task,rcu:rcu_unlock_preempted_task,rcu:rcu_quiescent_state_report,rcu:rcu_fqs,rcu:rcu_callback,rcu:rcu_kfree_callback,rcu:rcu_batch_start,rcu:rcu_invoke_callback,rcu:rcu_invoke_kfree_callback,rcu:rcu_batch_end,rcu:rcu_torture_read,rcu:rcu_barrier # Function-graph tracing: ftrace=function_graph ftrace_graph_filter=sched_setaffinity,migration_cpu_stop # Also --kconfig "CONFIG_FUNCTION_TRACER=y CONFIG_FUNCTION_GRAPH_TRACER=y" # Control buffer size: --bootargs trace_buf_size=3k # Get trace-buffer dumps on all oopses: --bootargs ftrace_dump_on_oops # Ditto, but dump only the oopsing CPU: --bootargs ftrace_dump_on_oops=orig_cpu # Heavy-handed way to also dump on warnings: --bootargs panic_on_warn