kexec-tools/mkdumprd
Tao Liu 0311f6e25b Set zstd as the default compression method for kdump initrd
zstd has better compression ratio and time consumption balance.
When no customized compression method specified in kdump.conf,
we will use zstd as the default compression method.

**The test method:

I installed kexec-tools with and without the patch, executing the following
command for 4 times, and calculate the averange time:

$ rm -f /boot/initramfs-*kdump.img && time kdumpctl rebuild && \
  ls -ail /boot/initramfs-*kdump.img

**The test result:

Bare metal x86_64 machine:
        dracut with squash module
         zlib     lzo      xz       lz4        zstd
real     10.6282  11.0398  11.395   8.6424    10.1676
user      9.8932  11.9072  14.2304  2.8286     8.6468
sys       3.523    3.4626   3.6028  3.5        3.4942
size of
kdump.img 30575616 31419392 27102208 36666368 29236224

        dracut without squash module
        zlib      lzo      xz       lz4        zstd
real     9.509    19.4876  11.6724  9.0338    10.267
user    10.6028   14.516   17.8662  4.0476     9.0936
sys      2.942     2.9184   3.0662  2.9232     3.0662
size of
kdump.img 19247949 19958120 14505056 21112544 17007764

PowerVM hosted ppc64le VM:
        dracut with squash module | dracut without sqaush module
         zlib        zstd         |  zlib          zstd
real     10.6742     10.7572      |   9.7676       10.5722
user     18.754      19.8338      |  20.7932       13.179
sys       1.8358      1.864       |   1.637         1.663
                                  |
size of                           |
kdump.img 36917248   35467264     |  21441323      19007108

**discussion

zstd has a better compression ratio and time consumption balance.

v1 -> v2:
Use kdump_get_conf_val() to get dracut_args values of kdump.conf

v2 -> v3:
Attached testing benchmark

v3 -> v4:
Re-measured and re-attached the testing benchmark of x86_64 and ppc64le.
Changed regex '.*[[:space:]]' to '(^|[[:space:]])'

v4 -> v5:
Attacked lzo/xz/lz4 testing benchmark.

v5 -> v6:
Add zstd as required in kexec-tools.spec

Hello Coiby, you may use "RELEASE=34 make test-run", for
CONFIG_RD_ZSTD is enabled since fc-cloud-34

Acked-by: Coiby Xu <coxu@redhat.com>
Signed-off-by: Tao Liu <ltao@redhat.com>
2022-01-06 08:16:27 +08:00

460 lines
11 KiB
Bash

#!/bin/bash --norc
# New mkdumprd
#
# Copyright 2011 Red Hat, Inc.
#
# Written by Cong Wang <amwang@redhat.com>
#
if [[ -f /etc/sysconfig/kdump ]]; then
. /etc/sysconfig/kdump
fi
[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
. $dracutbasedir/dracut-functions.sh
. /lib/kdump/kdump-lib.sh
. /lib/kdump/kdump-logger.sh
export IN_KDUMP=1
#initiate the kdump logger
if ! dlog_init; then
echo "failed to initiate the kdump logger."
exit 1
fi
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
SAVE_PATH=$(get_save_path)
OVERRIDE_RESETTABLE=0
extra_modules=""
dracut_args=(--add kdumpbase --quiet --hostonly --hostonly-cmdline --hostonly-i18n --hostonly-mode strict -o "plymouth resume ifcfg earlykdump")
MKDUMPRD_TMPDIR="$(mktemp -d -t mkdumprd.XXXXXX)"
[ -d "$MKDUMPRD_TMPDIR" ] || perror_exit "dracut: mktemp -p -d -t dracut.XXXXXX failed."
MKDUMPRD_TMPMNT="$MKDUMPRD_TMPDIR/target"
trap '
ret=$?;
is_mounted $MKDUMPRD_TMPMNT && umount -f $MKDUMPRD_TMPMNT;
[[ -d $MKDUMPRD_TMPDIR ]] && rm --one-file-system -rf -- "$MKDUMPRD_TMPDIR";
exit $ret;
' EXIT
# clean up after ourselves no matter how we die.
trap 'exit 1;' SIGINT
add_dracut_arg()
{
dracut_args+=("$@")
}
add_dracut_mount()
{
add_dracut_arg "--mount" "$1"
}
add_dracut_sshkey()
{
add_dracut_arg "--sshkey" "$1"
}
# caller should ensure $1 is valid and mounted in 1st kernel
to_mount()
{
local _target=$1 _fstype=$2 _options=$3 _sed_cmd _new_mntpoint _pdev
_new_mntpoint=$(get_kdump_mntpoint_from_target "$_target")
_fstype="${_fstype:-$(get_fs_type_from_target "$_target")}"
_options="${_options:-$(get_mntopt_from_target "$_target")}"
_options="${_options:-defaults}"
if [[ $_fstype == "nfs"* ]]; then
_pdev=$_target
_sed_cmd+='s/,\(mount\)\?addr=[^,]*//g;'
_sed_cmd+='s/,\(mount\)\?proto=[^,]*//g;'
_sed_cmd+='s/,clientaddr=[^,]*//;'
else
# for non-nfs _target converting to use udev persistent name
_pdev="$(kdump_get_persistent_dev "$_target")"
if [[ -z $_pdev ]]; then
return 1
fi
fi
# mount fs target as rw in 2nd kernel
_sed_cmd+='s/\(^\|,\)ro\($\|,\)/\1rw\2/g;'
# with 'noauto' in fstab nfs and non-root disk mount will fail in 2nd
# kernel, filter it out here.
_sed_cmd+='s/\(^\|,\)noauto\($\|,\)/\1/g;'
# drop nofail or nobootwait
_sed_cmd+='s/\(^\|,\)nofail\($\|,\)/\1/g;'
_sed_cmd+='s/\(^\|,\)nobootwait\($\|,\)/\1/g;'
_options=$(echo "$_options" | sed "$_sed_cmd")
echo "$_pdev $_new_mntpoint $_fstype $_options"
}
#Function: get_ssh_size
#$1=dump target
#called from while loop and shouldn't read from stdin, so we're using "ssh -n"
get_ssh_size()
{
local _out
local _opt=("-i" "$SSH_KEY_LOCATION" "-o" "BatchMode=yes" "-o" "StrictHostKeyChecking=yes")
if ! _out=$(ssh -q -n "${_opt[@]}" "$1" "df" "--output=avail" "$SAVE_PATH"); then
perror_exit "checking remote ssh server available size failed."
fi
echo -n "$_out" | tail -1
}
#mkdir if save path does not exist on ssh dump target
#$1=ssh dump target
#caller should ensure write permission on $1:$SAVE_PATH
#called from while loop and shouldn't read from stdin, so we're using "ssh -n"
mkdir_save_path_ssh()
{
local _opt _dir
_opt=(-i "$SSH_KEY_LOCATION" -o BatchMode=yes -o StrictHostKeyChecking=yes)
ssh -qn "${_opt[@]}" "$1" mkdir -p "$SAVE_PATH" &> /dev/null ||
perror_exit "mkdir failed on $1:$SAVE_PATH"
# check whether user has write permission on $1:$SAVE_PATH
_dir=$(ssh -qn "${_opt[@]}" "$1" mktemp -dqp "$SAVE_PATH" 2> /dev/null) ||
perror_exit "Could not create temporary directory on $1:$SAVE_PATH. Make sure user has write permission on destination"
ssh -qn "${_opt[@]}" "$1" rmdir "$_dir"
return 0
}
#Function: get_fs_size
#$1=dump target
get_fs_size()
{
df --output=avail "$(get_mntpoint_from_target "$1")/$SAVE_PATH" | tail -1
}
#Function: get_raw_size
#$1=dump target
get_raw_size()
{
fdisk -s "$1"
}
#Function: check_size
#$1: dump type string ('raw', 'fs', 'ssh')
#$2: dump target
check_size()
{
local avail memtotal
memtotal=$(awk '/MemTotal/{print $2}' /proc/meminfo)
case "$1" in
raw)
avail=$(get_raw_size "$2")
;;
ssh)
avail=$(get_ssh_size "$2")
;;
fs)
avail=$(get_fs_size "$2")
;;
*)
return
;;
esac || perror_exit "Check dump target size failed"
if [[ $avail -lt $memtotal ]]; then
dwarn "Warning: There might not be enough space to save a vmcore."
dwarn " The size of $2 should be greater than $memtotal kilo bytes."
fi
}
check_save_path_fs()
{
local _path=$1
if [[ ! -d $_path ]]; then
perror_exit "Dump path $_path does not exist."
fi
}
mount_failure()
{
local _target=$1
local _mnt=$2
local _fstype=$3
local msg="Failed to mount $_target"
if [[ -n $_mnt ]]; then
msg="$msg on $_mnt"
fi
msg="$msg for kdump preflight check."
if [[ $_fstype == "nfs" ]]; then
msg="$msg Please make sure nfs-utils has been installed."
fi
perror_exit "$msg"
}
check_user_configured_target()
{
local _target=$1 _cfg_fs_type=$2 _mounted
local _mnt _opt _fstype
_mnt=$(get_mntpoint_from_target "$_target")
_opt=$(get_mntopt_from_target "$_target")
_fstype=$(get_fs_type_from_target "$_target")
if [[ -n $_fstype ]]; then
# In case of nfs4, nfs should be used instead, nfs* options is deprecated in kdump.conf
[[ $_fstype == "nfs"* ]] && _fstype=nfs
if [[ -n $_cfg_fs_type ]] && [[ $_fstype != "$_cfg_fs_type" ]]; then
perror_exit "\"$_target\" have a wrong type config \"$_cfg_fs_type\", expected \"$_fstype\""
fi
else
_fstype="$_cfg_fs_type"
_fstype="$_cfg_fs_type"
fi
# For noauto mount, mount it inplace with default value.
# Else use the temporary target directory
if [[ -n $_mnt ]]; then
if ! is_mounted "$_mnt"; then
if [[ $_opt == *",noauto"* ]]; then
mount "$_mnt" || mount_failure "$_target" "$_mnt" "$_fstype"
_mounted=$_mnt
else
perror_exit "Dump target \"$_target\" is neither mounted nor configured as \"noauto\""
fi
fi
else
_mnt=$MKDUMPRD_TMPMNT
mkdir -p "$_mnt"
mount "$_target" "$_mnt" -t "$_fstype" -o defaults || mount_failure "$_target" "" "$_fstype"
_mounted=$_mnt
fi
# For user configured target, use $SAVE_PATH as the dump path within the target
if [[ ! -d "$_mnt/$SAVE_PATH" ]]; then
perror_exit "Dump path \"$_mnt/$SAVE_PATH\" does not exist in dump target \"$_target\""
fi
check_size fs "$_target"
# Unmount it early, if function is interrupted and didn't reach here, the shell trap will clear it up anyway
if [[ -n $_mounted ]]; then
umount -f -- "$_mounted"
fi
}
# $1: core_collector config value
verify_core_collector()
{
local _cmd="${1%% *}"
local _params="${1#* }"
if [[ $_cmd != "makedumpfile" ]]; then
if is_raw_dump_target; then
dwarn "Warning: specifying a non-makedumpfile core collector, you will have to recover the vmcore manually."
fi
return
fi
if is_ssh_dump_target || is_raw_dump_target; then
if ! strstr "$_params" "-F"; then
perror_exit 'The specified dump target needs makedumpfile "-F" option.'
fi
_params="$_params vmcore"
else
_params="$_params vmcore dumpfile"
fi
# shellcheck disable=SC2086
if ! $_cmd --check-params $_params; then
perror_exit "makedumpfile parameter check failed."
fi
}
add_mount()
{
local _mnt
_mnt=$(to_mount "$@") || exit 1
add_dracut_mount "$_mnt"
}
#handle the case user does not specify the dump target explicitly
handle_default_dump_target()
{
local _target
local _mntpoint
is_user_configured_dump_target && return
check_save_path_fs "$SAVE_PATH"
_save_path=$(get_bind_mount_source "$SAVE_PATH")
_target=$(get_target_from_path "$_save_path")
_mntpoint=$(get_mntpoint_from_target "$_target")
SAVE_PATH=${_save_path##"$_mntpoint"}
add_mount "$_target"
check_size fs "$_target"
}
# $1: function name
for_each_block_target()
{
local dev majmin
for dev in $(get_kdump_targets); do
[[ -b $dev ]] || continue
majmin=$(get_maj_min "$dev")
check_block_and_slaves "$1" "$majmin" && return 1
done
return 0
}
#judge if a specific device with $1 is unresettable
#return false if unresettable.
is_unresettable()
{
local path device resettable=1
path="/sys/$(udevadm info --query=all --path="/sys/dev/block/$1" | awk '/^P:/ {print $2}' | sed -e 's/\(cciss[0-9]\+\/\).*/\1/g' -e 's/\/block\/.*$//')/resettable"
if [[ -f $path ]]; then
resettable="$(< "$path")"
[[ $resettable -eq 0 ]] && [[ $OVERRIDE_RESETTABLE -eq 0 ]] && {
device=$(udevadm info --query=all --path="/sys/dev/block/$1" | awk -F= '/DEVNAME/{print $2}')
derror "Error: Can not save vmcore because device $device is unresettable"
return 0
}
fi
return 1
}
#check if machine is resettable.
#return true if resettable
check_resettable()
{
local _target _override_resettable
_override_resettable=$(kdump_get_conf_val override_resettable)
OVERRIDE_RESETTABLE=${_override_resettable:-$OVERRIDE_RESETTABLE}
if [ "$OVERRIDE_RESETTABLE" != "0" ] && [ "$OVERRIDE_RESETTABLE" != "1" ]; then
perror_exit "override_resettable value '$OVERRIDE_RESETTABLE' is invalid"
fi
for_each_block_target is_unresettable && return
return 1
}
check_crypt()
{
local _dev
for _dev in $(get_kdump_targets); do
if [[ -n $(get_luks_crypt_dev "$(get_maj_min "$_dev")") ]]; then
derror "Device $_dev is encrypted." && return 1
fi
done
}
if ! check_resettable; then
exit 1
fi
if ! check_crypt; then
dwarn "Warning: Encrypted device is in dump path, which is not recommended, see kexec-kdump-howto.txt for more details."
fi
# firstly get right SSH_KEY_LOCATION
keyfile=$(kdump_get_conf_val sshkey)
if [[ -f $keyfile ]]; then
# canonicalize the path
SSH_KEY_LOCATION=$(/usr/bin/readlink -m "$keyfile")
fi
while read -r config_opt config_val; do
# remove inline comments after the end of a directive.
case "$config_opt" in
extra_modules)
extra_modules="$extra_modules $config_val"
;;
ext[234] | xfs | btrfs | minix | nfs)
check_user_configured_target "$config_val" "$config_opt"
add_mount "$config_val" "$config_opt"
;;
raw)
# checking raw disk writable
dd if="$config_val" count=1 of=/dev/null > /dev/null 2>&1 || {
perror_exit "Bad raw disk $config_val"
}
_praw=$(persistent_policy="by-id" kdump_get_persistent_dev "$config_val")
if [[ -z $_praw ]]; then
exit 1
fi
add_dracut_arg "--device" "$_praw"
check_size raw "$config_val"
;;
ssh)
if strstr "$config_val" "@"; then
mkdir_save_path_ssh "$config_val"
check_size ssh "$config_val"
add_dracut_sshkey "$SSH_KEY_LOCATION"
else
perror_exit "Bad ssh dump target $config_val"
fi
;;
core_collector)
verify_core_collector "$config_val"
;;
dracut_args)
while read -r dracut_arg; do
add_dracut_arg "$dracut_arg"
done <<< "$(echo "$config_val" | xargs -n 1 echo)"
;;
*) ;;
esac
done <<< "$(kdump_read_conf)"
handle_default_dump_target
if ! have_compression_in_dracut_args; then
add_dracut_arg "--compress" "zstd"
fi
if [[ -n $extra_modules ]]; then
add_dracut_arg "--add-drivers" "$extra_modules"
fi
# TODO: The below check is not needed anymore with the introduction of
# 'zz-fadumpinit' module, that isolates fadump's capture kernel initrd,
# but still sysroot.mount unit gets generated based on 'root=' kernel
# parameter available in fadump case. So, find a way to fix that first
# before removing this check.
if ! is_fadump_capable; then
# The 2nd rootfs mount stays behind the normal dump target mount,
# so it doesn't affect the logic of check_dump_fs_modified().
is_dump_to_rootfs && add_mount "$(to_dev_name "$(get_root_fs_device)")"
add_dracut_arg "--no-hostonly-default-device"
fi
dracut "${dracut_args[@]}" "$@"
_rc=$?
sync
exit $_rc