diff mbox

migration: optimize the downtime

Message ID 1500522569-10760-1-git-send-email-jianjay.zhou@huawei.com (mailing list archive)
State New, archived
Headers show

Commit Message

Zhoujian (jay) July 20, 2017, 3:49 a.m. UTC
Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
with a 8U24G vm(20G is really occupied), the main cost comes from
KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
kvm_set_user_memory_region(). In kmod, the main cost is
kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
zap the unsync sptes.

I think it can be optimized:
(1) source vm will be destroyed if the migration is successfully done,
    so the resources will be cleanuped automatically by the system
(2) delay the cleanup if the migration failed

Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
---
 migration/migration.c | 16 +++++++++-------
 qmp.c                 | 10 ++++++++++
 2 files changed, 19 insertions(+), 7 deletions(-)

Comments

no-reply@patchew.org July 20, 2017, 4:23 a.m. UTC | #1
Hi,

This series failed automatic build test. Please find the testing commands and
their output below. If you have docker installed, you can probably reproduce it
locally.

Message-id: 1500522569-10760-1-git-send-email-jianjay.zhou@huawei.com
Subject: [Qemu-devel] [PATCH] migration: optimize the downtime
Type: series

=== TEST SCRIPT BEGIN ===
#!/bin/bash
set -e
git submodule update --init dtc
# Let docker tests dump environment info
export SHOW_ENV=1
export J=8
time make docker-test-quick@centos6
time make docker-test-build@min-glib
time make docker-test-mingw@fedora
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
Switched to a new branch 'test'
1ae581e migration: optimize the downtime

=== OUTPUT BEGIN ===
Submodule 'dtc' (git://git.qemu-project.org/dtc.git) registered for path 'dtc'
Cloning into '/var/tmp/patchew-tester-tmp-6slpqj5k/src/dtc'...
Submodule path 'dtc': checked out '558cd81bdd432769b59bff01240c44f82cfb1a9d'
  BUILD   centos6
make[1]: Entering directory '/var/tmp/patchew-tester-tmp-6slpqj5k/src'
  ARCHIVE qemu.tgz
  ARCHIVE dtc.tgz
  COPY    RUNNER
    RUN test-quick in qemu:centos6 
Packages installed:
SDL-devel-1.2.14-7.el6_7.1.x86_64
bison-2.4.1-5.el6.x86_64
ccache-3.1.6-2.el6.x86_64
epel-release-6-8.noarch
flex-2.5.35-9.el6.x86_64
gcc-4.4.7-18.el6.x86_64
git-1.7.1-8.el6.x86_64
glib2-devel-2.28.8-9.el6.x86_64
libfdt-devel-1.4.0-1.el6.x86_64
make-3.81-23.el6.x86_64
package g++ is not installed
pixman-devel-0.32.8-1.el6.x86_64
tar-1.23-15.el6_8.x86_64
zlib-devel-1.2.3-29.el6.x86_64

Environment variables:
PACKAGES=libfdt-devel ccache     tar git make gcc g++ flex bison     zlib-devel glib2-devel SDL-devel pixman-devel     epel-release
HOSTNAME=50d2403d8481
TERM=xterm
MAKEFLAGS= -j8
HISTSIZE=1000
J=8
USER=root
CCACHE_DIR=/var/tmp/ccache
EXTRA_CONFIGURE_OPTS=
V=
SHOW_ENV=1
MAIL=/var/spool/mail/root
PATH=/usr/lib/ccache:/usr/lib64/ccache:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
PWD=/
LANG=en_US.UTF-8
TARGET_LIST=
HISTCONTROL=ignoredups
SHLVL=1
HOME=/root
TEST_DIR=/tmp/qemu-test
LOGNAME=root
LESSOPEN=||/usr/bin/lesspipe.sh %s
FEATURES= dtc
DEBUG=
G_BROKEN_FILENAMES=1
CCACHE_HASHDIR=
_=/usr/bin/env

Configure options:
--enable-werror --target-list=x86_64-softmmu,aarch64-softmmu --prefix=/var/tmp/qemu-build/install
No C++ compiler available; disabling C++ specific optional code
Install prefix    /var/tmp/qemu-build/install
BIOS directory    /var/tmp/qemu-build/install/share/qemu
binary directory  /var/tmp/qemu-build/install/bin
library directory /var/tmp/qemu-build/install/lib
module directory  /var/tmp/qemu-build/install/lib/qemu
libexec directory /var/tmp/qemu-build/install/libexec
include directory /var/tmp/qemu-build/install/include
config directory  /var/tmp/qemu-build/install/etc
local state directory   /var/tmp/qemu-build/install/var
Manual directory  /var/tmp/qemu-build/install/share/man
ELF interp prefix /usr/gnemul/qemu-%M
Source path       /tmp/qemu-test/src
C compiler        cc
Host C compiler   cc
C++ compiler      
Objective-C compiler cc
ARFLAGS           rv
CFLAGS            -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g 
QEMU_CFLAGS       -I/usr/include/pixman-1   -I$(SRC_PATH)/dtc/libfdt -pthread -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include   -fPIE -DPIE -m64 -mcx16 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes -Wredundant-decls -Wall -Wundef -Wwrite-strings -Wmissing-prototypes -fno-strict-aliasing -fno-common -fwrapv  -Wendif-labels -Wno-missing-include-dirs -Wempty-body -Wnested-externs -Wformat-security -Wformat-y2k -Winit-self -Wignored-qualifiers -Wold-style-declaration -Wold-style-definition -Wtype-limits -fstack-protector-all
LDFLAGS           -Wl,--warn-common -Wl,-z,relro -Wl,-z,now -pie -m64 -g 
make              make
install           install
python            python -B
smbd              /usr/sbin/smbd
module support    no
host CPU          x86_64
host big endian   no
target list       x86_64-softmmu aarch64-softmmu
gprof enabled     no
sparse enabled    no
strip binaries    yes
profiler          no
static build      no
pixman            system
SDL support       yes (1.2.14)
GTK support       no 
GTK GL support    no
VTE support       no 
TLS priority      NORMAL
GNUTLS support    no
GNUTLS rnd        no
libgcrypt         no
libgcrypt kdf     no
nettle            no 
nettle kdf        no
libtasn1          no
curses support    no
virgl support     no
curl support      no
mingw32 support   no
Audio drivers     oss
Block whitelist (rw) 
Block whitelist (ro) 
VirtFS support    no
VNC support       yes
VNC SASL support  no
VNC JPEG support  no
VNC PNG support   no
xen support       no
brlapi support    no
bluez  support    no
Documentation     no
PIE               yes
vde support       no
netmap support    no
Linux AIO support no
ATTR/XATTR support yes
Install blobs     yes
KVM support       yes
HAX support       no
TCG support       yes
TCG debug enabled no
TCG interpreter   no
RDMA support      no
fdt support       yes
preadv support    yes
fdatasync         yes
madvise           yes
posix_madvise     yes
libcap-ng support no
vhost-net support yes
vhost-scsi support yes
vhost-vsock support yes
Trace backends    log
spice support     no 
rbd support       no
xfsctl support    no
smartcard support no
libusb            no
usb net redir     no
OpenGL support    no
OpenGL dmabufs    no
libiscsi support  no
libnfs support    no
build guest agent yes
QGA VSS support   no
QGA w32 disk info no
QGA MSI support   no
seccomp support   no
coroutine backend ucontext
coroutine pool    yes
debug stack usage no
crypto afalg      no
GlusterFS support no
gcov              gcov
gcov enabled      no
TPM support       yes
libssh2 support   no
TPM passthrough   yes
QOM debugging     yes
Live block migration yes
lzo support       no
snappy support    no
bzip2 support     no
NUMA host support no
tcmalloc support  no
jemalloc support  no
avx2 optimization no
replication support yes
VxHS block device no
  GEN     x86_64-softmmu/config-devices.mak.tmp
  GEN     aarch64-softmmu/config-devices.mak.tmp
mkdir -p dtc/libfdt
mkdir -p dtc/tests
  GEN     qemu-options.def
  GEN     config-host.h
  GEN     qmp-commands.h
  GEN     qapi-types.h
  GEN     qapi-visit.h
  GEN     qapi-event.h
  GEN     aarch64-softmmu/config-devices.mak
  GEN     x86_64-softmmu/config-devices.mak
  GEN     qmp-marshal.c
  GEN     qapi-types.c
  GEN     qapi-visit.c
  GEN     qapi-event.c
  GEN     qmp-introspect.h
  GEN     qmp-introspect.c
  GEN     trace/generated-tcg-tracers.h
  GEN     trace/generated-helpers-wrappers.h
  GEN     trace/generated-helpers.h
  GEN     trace/generated-helpers.c
  GEN     module_block.h
  GEN     tests/test-qapi-types.h
  GEN     tests/test-qapi-visit.h
  GEN     tests/test-qmp-commands.h
  GEN     tests/test-qapi-event.h
  GEN     tests/test-qmp-introspect.h
  GEN     trace-root.h
  GEN     util/trace.h
  GEN     crypto/trace.h
  GEN     io/trace.h
  GEN     migration/trace.h
  GEN     block/trace.h
  GEN     chardev/trace.h
  GEN     hw/block/trace.h
  GEN     hw/block/dataplane/trace.h
  GEN     hw/char/trace.h
  GEN     hw/intc/trace.h
  GEN     hw/net/trace.h
  GEN     hw/virtio/trace.h
  GEN     hw/audio/trace.h
  GEN     hw/misc/trace.h
  GEN     hw/usb/trace.h
  GEN     hw/scsi/trace.h
  GEN     hw/nvram/trace.h
  GEN     hw/display/trace.h
  GEN     hw/input/trace.h
  GEN     hw/timer/trace.h
  GEN     hw/dma/trace.h
  GEN     hw/sparc/trace.h
  GEN     hw/sd/trace.h
  GEN     hw/isa/trace.h
  GEN     hw/mem/trace.h
  GEN     hw/i386/trace.h
  GEN     hw/i386/xen/trace.h
  GEN     hw/9pfs/trace.h
  GEN     hw/ppc/trace.h
  GEN     hw/pci/trace.h
  GEN     hw/s390x/trace.h
  GEN     hw/vfio/trace.h
  GEN     hw/acpi/trace.h
  GEN     hw/arm/trace.h
  GEN     hw/alpha/trace.h
  GEN     hw/xen/trace.h
  GEN     ui/trace.h
  GEN     audio/trace.h
  GEN     net/trace.h
  GEN     target/arm/trace.h
  GEN     target/i386/trace.h
  GEN     target/mips/trace.h
  GEN     target/sparc/trace.h
  GEN     target/s390x/trace.h
  GEN     target/ppc/trace.h
  GEN     qom/trace.h
  GEN     linux-user/trace.h
  GEN     qapi/trace.h
  GEN     accel/tcg/trace.h
  GEN     accel/kvm/trace.h
  GEN     nbd/trace.h
  GEN     trace-root.c
  GEN     util/trace.c
  GEN     crypto/trace.c
  GEN     io/trace.c
  GEN     migration/trace.c
  GEN     block/trace.c
  GEN     chardev/trace.c
  GEN     hw/block/trace.c
  GEN     hw/block/dataplane/trace.c
  GEN     hw/char/trace.c
  GEN     hw/intc/trace.c
  GEN     hw/net/trace.c
  GEN     hw/virtio/trace.c
  GEN     hw/audio/trace.c
  GEN     hw/misc/trace.c
  GEN     hw/usb/trace.c
  GEN     hw/scsi/trace.c
  GEN     hw/nvram/trace.c
  GEN     hw/display/trace.c
  GEN     hw/input/trace.c
  GEN     hw/timer/trace.c
  GEN     hw/dma/trace.c
  GEN     hw/sparc/trace.c
  GEN     hw/sd/trace.c
  GEN     hw/isa/trace.c
  GEN     hw/mem/trace.c
  GEN     hw/i386/trace.c
  GEN     hw/i386/xen/trace.c
  GEN     hw/9pfs/trace.c
  GEN     hw/ppc/trace.c
  GEN     hw/pci/trace.c
  GEN     hw/s390x/trace.c
  GEN     hw/vfio/trace.c
  GEN     hw/acpi/trace.c
  GEN     hw/arm/trace.c
  GEN     hw/alpha/trace.c
  GEN     hw/xen/trace.c
  GEN     ui/trace.c
  GEN     audio/trace.c
  GEN     net/trace.c
  GEN     target/arm/trace.c
  GEN     target/i386/trace.c
  GEN     target/mips/trace.c
  GEN     target/sparc/trace.c
  GEN     target/s390x/trace.c
  GEN     target/ppc/trace.c
  GEN     qom/trace.c
  GEN     linux-user/trace.c
  GEN     qapi/trace.c
  GEN     accel/tcg/trace.c
  GEN     accel/kvm/trace.c
  GEN     nbd/trace.c
  GEN     config-all-devices.mak
	 DEP /tmp/qemu-test/src/dtc/tests/dumptrees.c
	 DEP /tmp/qemu-test/src/dtc/tests/testutils.c
	 DEP /tmp/qemu-test/src/dtc/tests/value-labels.c
	 DEP /tmp/qemu-test/src/dtc/tests/trees.S
	 DEP /tmp/qemu-test/src/dtc/tests/asm_tree_dump.c
	 DEP /tmp/qemu-test/src/dtc/tests/truncated_property.c
	 DEP /tmp/qemu-test/src/dtc/tests/check_path.c
	 DEP /tmp/qemu-test/src/dtc/tests/overlay_bad_fixup.c
	 DEP /tmp/qemu-test/src/dtc/tests/overlay.c
	 DEP /tmp/qemu-test/src/dtc/tests/subnode_iterate.c
	 DEP /tmp/qemu-test/src/dtc/tests/property_iterate.c
	 DEP /tmp/qemu-test/src/dtc/tests/utilfdt_test.c
	 DEP /tmp/qemu-test/src/dtc/tests/integer-expressions.c
	 DEP /tmp/qemu-test/src/dtc/tests/path_offset_aliases.c
	 DEP /tmp/qemu-test/src/dtc/tests/add_subnode_with_nops.c
	 DEP /tmp/qemu-test/src/dtc/tests/dtbs_equal_unordered.c
	 DEP /tmp/qemu-test/src/dtc/tests/dtb_reverse.c
	 DEP /tmp/qemu-test/src/dtc/tests/dtbs_equal_ordered.c
	 DEP /tmp/qemu-test/src/dtc/tests/extra-terminating-null.c
	 DEP /tmp/qemu-test/src/dtc/tests/incbin.c
	 DEP /tmp/qemu-test/src/dtc/tests/boot-cpuid.c
	 DEP /tmp/qemu-test/src/dtc/tests/phandle_format.c
	 DEP /tmp/qemu-test/src/dtc/tests/references.c
	 DEP /tmp/qemu-test/src/dtc/tests/path-references.c
	 DEP /tmp/qemu-test/src/dtc/tests/string_escapes.c
	 DEP /tmp/qemu-test/src/dtc/tests/propname_escapes.c
	 DEP /tmp/qemu-test/src/dtc/tests/appendprop2.c
	 DEP /tmp/qemu-test/src/dtc/tests/appendprop1.c
	 DEP /tmp/qemu-test/src/dtc/tests/del_node.c
	 DEP /tmp/qemu-test/src/dtc/tests/del_property.c
	 DEP /tmp/qemu-test/src/dtc/tests/setprop.c
	 DEP /tmp/qemu-test/src/dtc/tests/set_name.c
	 DEP /tmp/qemu-test/src/dtc/tests/rw_tree1.c
	 DEP /tmp/qemu-test/src/dtc/tests/open_pack.c
	 DEP /tmp/qemu-test/src/dtc/tests/nopulate.c
	 DEP /tmp/qemu-test/src/dtc/tests/move_and_save.c
	 DEP /tmp/qemu-test/src/dtc/tests/sw_tree1.c
	 DEP /tmp/qemu-test/src/dtc/tests/mangle-layout.c
	 DEP /tmp/qemu-test/src/dtc/tests/nop_node.c
	 DEP /tmp/qemu-test/src/dtc/tests/nop_property.c
	 DEP /tmp/qemu-test/src/dtc/tests/stringlist.c
	 DEP /tmp/qemu-test/src/dtc/tests/setprop_inplace.c
	 DEP /tmp/qemu-test/src/dtc/tests/addr_size_cells.c
	 DEP /tmp/qemu-test/src/dtc/tests/notfound.c
	 DEP /tmp/qemu-test/src/dtc/tests/sized_cells.c
	 DEP /tmp/qemu-test/src/dtc/tests/char_literal.c
	 DEP /tmp/qemu-test/src/dtc/tests/get_alias.c
	 DEP /tmp/qemu-test/src/dtc/tests/node_offset_by_compatible.c
	 DEP /tmp/qemu-test/src/dtc/tests/node_check_compatible.c
	 DEP /tmp/qemu-test/src/dtc/tests/node_offset_by_phandle.c
	 DEP /tmp/qemu-test/src/dtc/tests/node_offset_by_prop_value.c
	 DEP /tmp/qemu-test/src/dtc/tests/parent_offset.c
	 DEP /tmp/qemu-test/src/dtc/tests/supernode_atdepth_offset.c
	 DEP /tmp/qemu-test/src/dtc/tests/get_path.c
	 DEP /tmp/qemu-test/src/dtc/tests/get_phandle.c
	 DEP /tmp/qemu-test/src/dtc/tests/getprop.c
	 DEP /tmp/qemu-test/src/dtc/tests/get_name.c
	 DEP /tmp/qemu-test/src/dtc/tests/path_offset.c
	 DEP /tmp/qemu-test/src/dtc/tests/subnode_offset.c
	 DEP /tmp/qemu-test/src/dtc/tests/find_property.c
	 DEP /tmp/qemu-test/src/dtc/tests/root_node.c
	 DEP /tmp/qemu-test/src/dtc/tests/get_mem_rsv.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_addresses.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_overlay.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_empty_tree.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_strerror.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_rw.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_sw.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_wip.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt_ro.c
	 DEP /tmp/qemu-test/src/dtc/libfdt/fdt.c
	 DEP /tmp/qemu-test/src/dtc/util.c
	 DEP /tmp/qemu-test/src/dtc/fdtput.c
	 DEP /tmp/qemu-test/src/dtc/fdtget.c
	 DEP /tmp/qemu-test/src/dtc/fdtdump.c
	 LEX convert-dtsv0-lexer.lex.c
	 DEP /tmp/qemu-test/src/dtc/srcpos.c
	 BISON dtc-parser.tab.c
	 LEX dtc-lexer.lex.c
	 DEP /tmp/qemu-test/src/dtc/treesource.c
	 DEP /tmp/qemu-test/src/dtc/livetree.c
	 DEP /tmp/qemu-test/src/dtc/fstree.c
	 DEP /tmp/qemu-test/src/dtc/flattree.c
	 DEP /tmp/qemu-test/src/dtc/dtc.c
	 DEP /tmp/qemu-test/src/dtc/data.c
	 DEP /tmp/qemu-test/src/dtc/checks.c
	 DEP convert-dtsv0-lexer.lex.c
	 DEP dtc-parser.tab.c
	 DEP dtc-lexer.lex.c
	CHK version_gen.h
	UPD version_gen.h
	 DEP /tmp/qemu-test/src/dtc/util.c
	 CC libfdt/fdt.o
	 CC libfdt/fdt_ro.o
	 CC libfdt/fdt_wip.o
	 CC libfdt/fdt_sw.o
	 CC libfdt/fdt_rw.o
	 CC libfdt/fdt_strerror.o
	 CC libfdt/fdt_empty_tree.o
	 CC libfdt/fdt_addresses.o
	 CC libfdt/fdt_overlay.o
	 AR libfdt/libfdt.a
ar: creating libfdt/libfdt.a
a - libfdt/fdt.o
a - libfdt/fdt_ro.o
a - libfdt/fdt_wip.o
a - libfdt/fdt_sw.o
a - libfdt/fdt_rw.o
a - libfdt/fdt_strerror.o
a - libfdt/fdt_empty_tree.o
a - libfdt/fdt_addresses.o
a - libfdt/fdt_overlay.o
  CC      tests/qemu-iotests/socket_scm_helper.o
  GEN     qga/qapi-generated/qga-qapi-types.h
  GEN     qga/qapi-generated/qga-qapi-visit.h
  GEN     qga/qapi-generated/qga-qmp-commands.h
  GEN     qga/qapi-generated/qga-qapi-types.c
  GEN     qga/qapi-generated/qga-qapi-visit.c
  CC      qmp-introspect.o
  GEN     qga/qapi-generated/qga-qmp-marshal.c
  CC      qapi-visit.o
  CC      qapi/qapi-visit-core.o
  CC      qapi-event.o
  CC      qapi/qapi-dealloc-visitor.o
  CC      qapi/qobject-input-visitor.o
  CC      qapi-types.o
  CC      qapi/qobject-output-visitor.o
  CC      qapi/qmp-registry.o
  CC      qapi/qmp-dispatch.o
  CC      qapi/string-input-visitor.o
  CC      qapi/string-output-visitor.o
  CC      qapi/opts-visitor.o
  CC      qapi/qapi-clone-visitor.o
  CC      qapi/qmp-event.o
  CC      qapi/qapi-util.o
  CC      qobject/qnull.o
  CC      qobject/qnum.o
  CC      qobject/qstring.o
  CC      qobject/qdict.o
  CC      qobject/qlist.o
  CC      qobject/qbool.o
  CC      qobject/qjson.o
  CC      qobject/qobject.o
  CC      qobject/json-lexer.o
  CC      qobject/json-streamer.o
  CC      qobject/json-parser.o
  CC      trace/control.o
  CC      trace/qmp.o
  CC      util/osdep.o
  CC      util/cutils.o
  CC      util/qemu-timer-common.o
  CC      util/unicode.o
  CC      util/bufferiszero.o
  CC      util/lockcnt.o
  CC      util/aiocb.o
  CC      util/async.o
  CC      util/thread-pool.o
  CC      util/main-loop.o
  CC      util/qemu-timer.o
  CC      util/iohandler.o
  CC      util/compatfd.o
  CC      util/aio-posix.o
  CC      util/event_notifier-posix.o
  CC      util/mmap-alloc.o
  CC      util/oslib-posix.o
  CC      util/qemu-thread-posix.o
  CC      util/qemu-openpty.o
  CC      util/memfd.o
  CC      util/envlist.o
  CC      util/path.o
  CC      util/host-utils.o
  CC      util/module.o
  CC      util/bitmap.o
  CC      util/bitops.o
  CC      util/acl.o
  CC      util/fifo8.o
  CC      util/hbitmap.o
  CC      util/cacheinfo.o
  CC      util/error.o
  CC      util/qemu-error.o
  CC      util/id.o
  CC      util/iov.o
  CC      util/qemu-config.o
  CC      util/qemu-sockets.o
  CC      util/uri.o
  CC      util/notify.o
  CC      util/qemu-option.o
  CC      util/qemu-progress.o
  CC      util/keyval.o
  CC      util/hexdump.o
  CC      util/crc32c.o
  CC      util/uuid.o
  CC      util/throttle.o
  CC      util/getauxval.o
  CC      util/readline.o
  CC      util/rcu.o
  CC      util/qemu-coroutine.o
  CC      util/qemu-coroutine-lock.o
  CC      util/qemu-coroutine-io.o
  CC      util/qemu-coroutine-sleep.o
  CC      util/buffer.o
  CC      util/coroutine-ucontext.o
  CC      util/timed-average.o
  CC      util/base64.o
  CC      util/log.o
  CC      util/qdist.o
  CC      util/qht.o
  CC      util/range.o
  CC      util/stats64.o
  CC      trace-root.o
  CC      util/systemd.o
  CC      util/trace.o
  CC      crypto/trace.o
  CC      io/trace.o
  CC      migration/trace.o
  CC      block/trace.o
  CC      hw/block/trace.o
  CC      chardev/trace.o
  CC      hw/block/dataplane/trace.o
  CC      hw/char/trace.o
  CC      hw/net/trace.o
  CC      hw/intc/trace.o
  CC      hw/virtio/trace.o
  CC      hw/audio/trace.o
  CC      hw/misc/trace.o
  CC      hw/usb/trace.o
  CC      hw/scsi/trace.o
  CC      hw/nvram/trace.o
  CC      hw/display/trace.o
  CC      hw/input/trace.o
  CC      hw/timer/trace.o
  CC      hw/dma/trace.o
  CC      hw/sparc/trace.o
  CC      hw/sd/trace.o
  CC      hw/isa/trace.o
  CC      hw/mem/trace.o
  CC      hw/i386/trace.o
  CC      hw/i386/xen/trace.o
  CC      hw/9pfs/trace.o
  CC      hw/pci/trace.o
  CC      hw/ppc/trace.o
  CC      hw/s390x/trace.o
  CC      hw/vfio/trace.o
  CC      hw/acpi/trace.o
  CC      hw/arm/trace.o
  CC      hw/alpha/trace.o
  CC      ui/trace.o
  CC      audio/trace.o
  CC      hw/xen/trace.o
  CC      net/trace.o
  CC      target/arm/trace.o
  CC      target/i386/trace.o
  CC      target/mips/trace.o
  CC      target/sparc/trace.o
  CC      target/ppc/trace.o
  CC      target/s390x/trace.o
  CC      qom/trace.o
  CC      linux-user/trace.o
  CC      qapi/trace.o
  CC      accel/tcg/trace.o
  CC      accel/kvm/trace.o
  CC      nbd/trace.o
  CC      crypto/pbkdf-stub.o
  CC      stubs/arch-query-cpu-def.o
  CC      stubs/arch-query-cpu-model-expansion.o
  CC      stubs/arch-query-cpu-model-comparison.o
  CC      stubs/arch-query-cpu-model-baseline.o
  CC      stubs/bdrv-next-monitor-owned.o
  CC      stubs/blk-commit-all.o
  CC      stubs/blockdev-close-all-bdrv-states.o
  CC      stubs/clock-warp.o
  CC      stubs/cpu-get-clock.o
  CC      stubs/dump.o
  CC      stubs/cpu-get-icount.o
  CC      stubs/error-printf.o
  CC      stubs/fdset.o
  CC      stubs/gdbstub.o
  CC      stubs/get-vm-name.o
  CC      stubs/iothread.o
  CC      stubs/iothread-lock.o
  CC      stubs/is-daemonized.o
  CC      stubs/machine-init-done.o
  CC      stubs/migr-blocker.o
  CC      stubs/monitor.o
  CC      stubs/notify-event.o
  CC      stubs/qtest.o
  CC      stubs/replay.o
  CC      stubs/runstate-check.o
  CC      stubs/set-fd-handler.o
  CC      stubs/slirp.o
  CC      stubs/sysbus.o
  CC      stubs/trace-control.o
  CC      stubs/uuid.o
  CC      stubs/vm-stop.o
  CC      stubs/vmstate.o
  CC      stubs/qmp_pc_dimm_device_list.o
  CC      stubs/target-monitor-defs.o
  CC      stubs/target-get-monitor-def.o
  CC      stubs/pc_madt_cpu_entry.o
  CC      stubs/vmgenid.o
  CC      stubs/xen-common.o
  CC      stubs/xen-hvm.o
  CC      contrib/ivshmem-client/ivshmem-client.o
  CC      contrib/ivshmem-client/main.o
  CC      contrib/ivshmem-server/ivshmem-server.o
  CC      contrib/ivshmem-server/main.o
  CC      qemu-nbd.o
  CC      block.o
  CC      blockjob.o
  CC      qemu-io-cmds.o
  CC      replication.o
  CC      block/raw-format.o
  CC      block/qcow.o
  CC      block/vdi.o
  CC      block/vmdk.o
  CC      block/cloop.o
  CC      block/bochs.o
  CC      block/vpc.o
  CC      block/vvfat.o
  CC      block/dmg.o
  CC      block/qcow2.o
  CC      block/qcow2-refcount.o
  CC      block/qcow2-cluster.o
  CC      block/qcow2-cache.o
  CC      block/qcow2-snapshot.o
  CC      block/qcow2-bitmap.o
  CC      block/qed.o
  CC      block/qed-l2-cache.o
  CC      block/qed-table.o
  CC      block/qed-cluster.o
  CC      block/qed-check.o
  CC      block/vhdx.o
  CC      block/vhdx-endian.o
  CC      block/vhdx-log.o
  CC      block/quorum.o
  CC      block/parallels.o
  CC      block/blkdebug.o
  CC      block/blkverify.o
  CC      block/block-backend.o
  CC      block/snapshot.o
  CC      block/blkreplay.o
  CC      block/qapi.o
  CC      block/file-posix.o
  CC      block/null.o
  CC      block/mirror.o
  CC      block/commit.o
  CC      block/io.o
  CC      block/throttle-groups.o
  CC      block/nbd.o
  CC      block/nbd-client.o
  CC      block/sheepdog.o
  CC      block/accounting.o
  CC      block/dirty-bitmap.o
  CC      block/write-threshold.o
  CC      block/replication.o
  CC      block/backup.o
  CC      block/crypto.o
  CC      nbd/server.o
  CC      nbd/client.o
  CC      nbd/common.o
  CC      crypto/init.o
  CC      crypto/hash.o
  CC      crypto/hmac.o
  CC      crypto/hash-glib.o
  CC      crypto/hmac-glib.o
  CC      crypto/aes.o
  CC      crypto/desrfb.o
  CC      crypto/cipher.o
  CC      crypto/tlscreds.o
  CC      crypto/tlscredsanon.o
  CC      crypto/tlscredsx509.o
  CC      crypto/tlssession.o
  CC      crypto/secret.o
  CC      crypto/random-platform.o
  CC      crypto/pbkdf.o
  CC      crypto/ivgen.o
  CC      crypto/ivgen-essiv.o
  CC      crypto/ivgen-plain.o
  CC      crypto/afsplit.o
  CC      crypto/ivgen-plain64.o
  CC      crypto/xts.o
  CC      crypto/block.o
  CC      crypto/block-qcow.o
  CC      crypto/block-luks.o
  CC      io/channel.o
  CC      io/channel-command.o
  CC      io/channel-buffer.o
  CC      io/channel-file.o
  CC      io/channel-socket.o
  CC      io/channel-tls.o
  CC      io/channel-watch.o
  CC      io/channel-websock.o
  CC      io/channel-util.o
  CC      io/dns-resolver.o
  CC      io/task.o
  CC      qom/object.o
  CC      qom/container.o
  CC      qom/qom-qobject.o
  CC      qom/object_interfaces.o
  GEN     qemu-img-cmds.h
  CC      qemu-io.o
  CC      qemu-bridge-helper.o
  CC      blockdev.o
  CC      bootdevice.o
  CC      iothread.o
  CC      blockdev-nbd.o
  CC      device-hotplug.o
  CC      qdev-monitor.o
  CC      os-posix.o
  CC      bt-vhci.o
  CC      bt-host.o
  CC      dma-helpers.o
  CC      vl.o
  CC      device_tree.o
  CC      tpm.o
  CC      qmp-marshal.o
  CC      qmp.o
  CC      hmp.o
  CC      cpus-common.o
  CC      audio/audio.o
  CC      audio/wavaudio.o
  CC      audio/noaudio.o
  CC      audio/mixeng.o
  CC      audio/sdlaudio.o
  CC      audio/ossaudio.o
  CC      audio/wavcapture.o
  CC      backends/rng.o
  CC      backends/rng-egd.o
  CC      backends/rng-random.o
  CC      backends/tpm.o
  CC      backends/hostmem.o
  CC      backends/hostmem-ram.o
  CC      backends/hostmem-file.o
  CC      backends/cryptodev.o
  CC      backends/cryptodev-builtin.o
  CC      block/stream.o
  CC      chardev/msmouse.o
  CC      chardev/wctablet.o
  CC      chardev/testdev.o
  CC      disas/arm.o
  CC      disas/i386.o
  CC      fsdev/qemu-fsdev-dummy.o
  CC      fsdev/qemu-fsdev-opts.o
  CC      fsdev/qemu-fsdev-throttle.o
  CC      hw/acpi/core.o
  CC      hw/acpi/piix4.o
  CC      hw/acpi/pcihp.o
  CC      hw/acpi/ich9.o
  CC      hw/acpi/tco.o
  CC      hw/acpi/cpu_hotplug.o
  CC      hw/acpi/memory_hotplug.o
  CC      hw/acpi/cpu.o
  CC      hw/acpi/nvdimm.o
  CC      hw/acpi/vmgenid.o
  CC      hw/acpi/acpi_interface.o
  CC      hw/acpi/bios-linker-loader.o
  CC      hw/acpi/aml-build.o
  CC      hw/acpi/ipmi.o
  CC      hw/acpi/acpi-stub.o
  CC      hw/acpi/ipmi-stub.o
  CC      hw/audio/sb16.o
  CC      hw/audio/es1370.o
  CC      hw/audio/ac97.o
  CC      hw/audio/fmopl.o
  CC      hw/audio/adlib.o
  CC      hw/audio/gus.o
  CC      hw/audio/gusemu_mixer.o
  CC      hw/audio/gusemu_hal.o
  CC      hw/audio/cs4231a.o
  CC      hw/audio/intel-hda.o
  CC      hw/audio/hda-codec.o
  CC      hw/audio/pcspk.o
  CC      hw/audio/wm8750.o
  CC      hw/audio/pl041.o
  CC      hw/audio/lm4549.o
  CC      hw/audio/marvell_88w8618.o
  CC      hw/audio/soundhw.o
  CC      hw/block/cdrom.o
  CC      hw/block/block.o
  CC      hw/block/hd-geometry.o
  CC      hw/block/fdc.o
  CC      hw/block/m25p80.o
  CC      hw/block/nand.o
  CC      hw/block/pflash_cfi01.o
  CC      hw/block/pflash_cfi02.o
  CC      hw/block/ecc.o
  CC      hw/block/onenand.o
  CC      hw/block/nvme.o
  CC      hw/bt/core.o
  CC      hw/bt/l2cap.o
  CC      hw/bt/sdp.o
  CC      hw/bt/hci.o
  CC      hw/char/ipoctal232.o
  CC      hw/bt/hid.o
  CC      hw/bt/hci-csr.o
  CC      hw/char/parallel.o
  CC      hw/char/pl011.o
  CC      hw/char/serial.o
  CC      hw/char/serial-isa.o
  CC      hw/char/serial-pci.o
  CC      hw/char/virtio-console.o
  CC      hw/char/cadence_uart.o
  CC      hw/char/cmsdk-apb-uart.o
  CC      hw/char/debugcon.o
  CC      hw/char/imx_serial.o
  CC      hw/core/qdev.o
  CC      hw/core/qdev-properties.o
  CC      hw/core/bus.o
  CC      hw/core/reset.o
  CC      hw/core/fw-path-provider.o
  CC      hw/core/irq.o
  CC      hw/core/hotplug.o
  CC      hw/core/nmi.o
  CC      hw/core/ptimer.o
  CC      hw/core/sysbus.o
  CC      hw/core/machine.o
  CC      hw/core/loader.o
  CC      hw/core/qdev-properties-system.o
  CC      hw/core/register.o
  CC      hw/core/or-irq.o
  CC      hw/core/platform-bus.o
  CC      hw/cpu/core.o
  CC      hw/display/ads7846.o
  CC      hw/display/cirrus_vga.o
  CC      hw/display/pl110.o
  CC      hw/display/ssd0303.o
  CC      hw/display/ssd0323.o
  CC      hw/display/vga-pci.o
  CC      hw/display/vga-isa.o
  CC      hw/display/vmware_vga.o
  CC      hw/display/blizzard.o
  CC      hw/display/exynos4210_fimd.o
  CC      hw/display/tc6393xb.o
  CC      hw/display/framebuffer.o
  CC      hw/dma/pl080.o
  CC      hw/dma/pl330.o
  CC      hw/dma/xlnx-zynq-devcfg.o
  CC      hw/gpio/max7310.o
  CC      hw/dma/i8257.o
  CC      hw/gpio/pl061.o
  CC      hw/gpio/zaurus.o
  CC      hw/gpio/gpio_key.o
  CC      hw/i2c/core.o
  CC      hw/i2c/smbus.o
  CC      hw/i2c/smbus_eeprom.o
  CC      hw/i2c/versatile_i2c.o
  CC      hw/i2c/i2c-ddc.o
  CC      hw/i2c/smbus_ich9.o
  CC      hw/i2c/pm_smbus.o
  CC      hw/i2c/bitbang_i2c.o
  CC      hw/i2c/imx_i2c.o
  CC      hw/i2c/aspeed_i2c.o
  CC      hw/ide/core.o
  CC      hw/i2c/exynos4210_i2c.o
  CC      hw/ide/atapi.o
  CC      hw/ide/qdev.o
  CC      hw/ide/pci.o
  CC      hw/ide/isa.o
  CC      hw/ide/piix.o
  CC      hw/ide/microdrive.o
  CC      hw/ide/ahci.o
  CC      hw/ide/ich.o
  CC      hw/input/hid.o
  CC      hw/input/lm832x.o
  CC      hw/input/pckbd.o
  CC      hw/input/pl050.o
  CC      hw/input/ps2.o
  CC      hw/input/stellaris_input.o
  CC      hw/input/vmmouse.o
  CC      hw/input/tsc2005.o
  CC      hw/input/virtio-input.o
  CC      hw/input/virtio-input-hid.o
  CC      hw/input/virtio-input-host.o
  CC      hw/intc/i8259_common.o
  CC      hw/intc/i8259.o
  CC      hw/intc/pl190.o
  CC      hw/intc/imx_avic.o
  CC      hw/intc/realview_gic.o
  CC      hw/intc/ioapic_common.o
  CC      hw/intc/arm_gic_common.o
  CC      hw/intc/arm_gic.o
  CC      hw/intc/arm_gicv2m.o
  CC      hw/intc/arm_gicv3_common.o
  CC      hw/intc/arm_gicv3.o
  CC      hw/intc/arm_gicv3_dist.o
  CC      hw/intc/arm_gicv3_redist.o
  CC      hw/intc/arm_gicv3_its_common.o
  CC      hw/intc/intc.o
  CC      hw/ipack/ipack.o
  CC      hw/ipack/tpci200.o
  CC      hw/ipmi/ipmi.o
  CC      hw/ipmi/ipmi_bmc_sim.o
  CC      hw/ipmi/ipmi_bmc_extern.o
  CC      hw/ipmi/isa_ipmi_bt.o
  CC      hw/ipmi/isa_ipmi_kcs.o
  CC      hw/isa/isa-bus.o
  CC      hw/isa/apm.o
  CC      hw/mem/pc-dimm.o
  CC      hw/mem/nvdimm.o
  CC      hw/misc/applesmc.o
  CC      hw/misc/max111x.o
  CC      hw/misc/tmp105.o
  CC      hw/misc/tmp421.o
  CC      hw/misc/debugexit.o
  CC      hw/misc/sga.o
  CC      hw/misc/pc-testdev.o
  CC      hw/misc/edu.o
  CC      hw/misc/unimp.o
  CC      hw/misc/arm_l2x0.o
  CC      hw/misc/arm_integrator_debug.o
  CC      hw/misc/a9scu.o
  CC      hw/misc/pci-testdev.o
  CC      hw/misc/arm11scu.o
  CC      hw/net/ne2000.o
  CC      hw/net/pcnet-pci.o
  CC      hw/net/pcnet.o
  CC      hw/net/e1000.o
  CC      hw/net/eepro100.o
  CC      hw/net/e1000x_common.o
  CC      hw/net/net_tx_pkt.o
  CC      hw/net/net_rx_pkt.o
  CC      hw/net/e1000e.o
  CC      hw/net/e1000e_core.o
  CC      hw/net/rtl8139.o
  CC      hw/net/vmxnet3.o
  CC      hw/net/smc91c111.o
  CC      hw/net/lan9118.o
  CC      hw/net/ne2000-isa.o
  CC      hw/net/xgmac.o
  CC      hw/net/allwinner_emac.o
  CC      hw/net/imx_fec.o
  CC      hw/net/cadence_gem.o
  CC      hw/net/stellaris_enet.o
  CC      hw/net/ftgmac100.o
  CC      hw/net/rocker/rocker.o
  CC      hw/net/rocker/rocker_fp.o
  CC      hw/net/rocker/rocker_desc.o
  CC      hw/net/rocker/rocker_world.o
  CC      hw/net/rocker/rocker_of_dpa.o
  CC      hw/nvram/eeprom93xx.o
  CC      hw/nvram/fw_cfg.o
  CC      hw/nvram/chrp_nvram.o
  CC      hw/pci-bridge/pci_bridge_dev.o
  CC      hw/pci-bridge/pcie_root_port.o
  CC      hw/pci-bridge/gen_pcie_root_port.o
  CC      hw/pci-bridge/pci_expander_bridge.o
  CC      hw/pci-bridge/xio3130_upstream.o
  CC      hw/pci-bridge/ioh3420.o
  CC      hw/pci-bridge/xio3130_downstream.o
  CC      hw/pci-bridge/i82801b11.o
  CC      hw/pci-host/pam.o
  CC      hw/pci-host/versatile.o
  CC      hw/pci-host/piix.o
  CC      hw/pci-host/q35.o
  CC      hw/pci-host/gpex.o
  CC      hw/pci/pci.o
  CC      hw/pci/pci_bridge.o
  CC      hw/pci/msix.o
  CC      hw/pci/msi.o
  CC      hw/pci/shpc.o
  CC      hw/pci/slotid_cap.o
  CC      hw/pci/pci_host.o
  CC      hw/pci/pcie_host.o
  CC      hw/pci/pcie.o
  CC      hw/pci/pcie_aer.o
  CC      hw/pci/pcie_port.o
  CC      hw/pci/pci-stub.o
  CC      hw/scsi/scsi-disk.o
  CC      hw/pcmcia/pcmcia.o
  CC      hw/scsi/scsi-generic.o
  CC      hw/scsi/scsi-bus.o
  CC      hw/scsi/lsi53c895a.o
  CC      hw/scsi/mptsas.o
  CC      hw/scsi/mptconfig.o
  CC      hw/scsi/megasas.o
  CC      hw/scsi/mptendian.o
  CC      hw/scsi/esp.o
  CC      hw/scsi/vmw_pvscsi.o
  CC      hw/scsi/esp-pci.o
  CC      hw/sd/pl181.o
  CC      hw/sd/ssi-sd.o
  CC      hw/sd/sd.o
  CC      hw/sd/core.o
  CC      hw/smbios/smbios.o
  CC      hw/sd/sdhci.o
  CC      hw/smbios/smbios_type_38.o
  CC      hw/smbios/smbios-stub.o
  CC      hw/smbios/smbios_type_38-stub.o
  CC      hw/ssi/pl022.o
  CC      hw/ssi/ssi.o
  CC      hw/ssi/xilinx_spips.o
  CC      hw/ssi/aspeed_smc.o
  CC      hw/ssi/stm32f2xx_spi.o
  CC      hw/timer/arm_timer.o
  CC      hw/timer/arm_mptimer.o
  CC      hw/timer/armv7m_systick.o
  CC      hw/timer/a9gtimer.o
  CC      hw/timer/cadence_ttc.o
  CC      hw/timer/ds1338.o
  CC      hw/timer/hpet.o
  CC      hw/timer/i8254_common.o
  CC      hw/timer/i8254.o
  CC      hw/timer/pl031.o
  CC      hw/timer/twl92230.o
  CC      hw/timer/imx_epit.o
  CC      hw/timer/stm32f2xx_timer.o
  CC      hw/timer/aspeed_timer.o
  CC      hw/timer/imx_gpt.o
  CC      hw/timer/cmsdk-apb-timer.o
  CC      hw/tpm/tpm_tis.o
  CC      hw/tpm/tpm_passthrough.o
  CC      hw/tpm/tpm_util.o
  CC      hw/usb/core.o
  CC      hw/usb/combined-packet.o
  CC      hw/usb/bus.o
  CC      hw/usb/libhw.o
  CC      hw/usb/desc.o
  CC      hw/usb/desc-msos.o
  CC      hw/usb/hcd-uhci.o
  CC      hw/usb/hcd-ohci.o
  CC      hw/usb/hcd-ehci.o
  CC      hw/usb/hcd-ehci-pci.o
  CC      hw/usb/hcd-ehci-sysbus.o
  CC      hw/usb/hcd-xhci.o
  CC      hw/usb/hcd-xhci-nec.o
  CC      hw/usb/hcd-musb.o
  CC      hw/usb/dev-hub.o
  CC      hw/usb/dev-hid.o
  CC      hw/usb/dev-wacom.o
  CC      hw/usb/dev-storage.o
  CC      hw/usb/dev-uas.o
  CC      hw/usb/dev-audio.o
  CC      hw/usb/dev-network.o
  CC      hw/usb/dev-serial.o
  CC      hw/usb/dev-bluetooth.o
  CC      hw/usb/dev-smartcard-reader.o
  CC      hw/usb/dev-mtp.o
  CC      hw/usb/host-stub.o
  CC      hw/virtio/virtio-rng.o
  CC      hw/virtio/virtio-pci.o
  CC      hw/virtio/virtio-bus.o
  CC      hw/virtio/virtio-mmio.o
  CC      hw/virtio/vhost-stub.o
  CC      hw/watchdog/watchdog.o
  CC      hw/watchdog/wdt_ib700.o
  CC      hw/watchdog/wdt_i6300esb.o
  CC      hw/watchdog/wdt_aspeed.o
  CC      migration/migration.o
  CC      migration/socket.o
  CC      migration/fd.o
  CC      migration/exec.o
  CC      migration/tls.o
  CC      migration/channel.o
  CC      migration/savevm.o
  CC      migration/colo-comm.o
  CC      migration/colo.o
  CC      migration/colo-failover.o
  CC      migration/vmstate.o
  CC      migration/vmstate-types.o
  CC      migration/page_cache.o
  CC      migration/qemu-file.o
  CC      migration/global_state.o
  CC      migration/qemu-file-channel.o
  CC      migration/xbzrle.o
  CC      migration/postcopy-ram.o
  CC      migration/qjson.o
  CC      migration/block.o
  CC      net/net.o
  CC      net/queue.o
  CC      net/checksum.o
  CC      net/util.o
  CC      net/hub.o
  CC      net/socket.o
  CC      net/dump.o
  CC      net/eth.o
  CC      net/l2tpv3.o
  CC      net/slirp.o
  CC      net/vhost-user.o
  CC      net/filter.o
  CC      net/filter-buffer.o
  CC      net/filter-mirror.o
  CC      net/colo-compare.o
  CC      net/colo.o
  CC      net/filter-rewriter.o
  CC      net/filter-replay.o
  CC      net/tap.o
  CC      net/tap-linux.o
  CC      qom/cpu.o
  CC      replay/replay.o
  CC      replay/replay-internal.o
  CC      replay/replay-events.o
  CC      replay/replay-time.o
  CC      replay/replay-input.o
  CC      replay/replay-char.o
  CC      replay/replay-snapshot.o
/tmp/qemu-test/src/replay/replay-internal.c: In function ‘replay_put_array’:
/tmp/qemu-test/src/replay/replay-internal.c:65: warning: ignoring return value of ‘fwrite’, declared with attribute warn_unused_result
  CC      replay/replay-net.o
  CC      replay/replay-audio.o
  CC      slirp/cksum.o
  CC      slirp/if.o
  CC      slirp/ip_icmp.o
  CC      slirp/ip6_icmp.o
  CC      slirp/ip6_input.o
  CC      slirp/ip6_output.o
  CC      slirp/ip_input.o
  CC      slirp/dnssearch.o
  CC      slirp/ip_output.o
  CC      slirp/dhcpv6.o
  CC      slirp/slirp.o
  CC      slirp/mbuf.o
  CC      slirp/misc.o
  CC      slirp/sbuf.o
  CC      slirp/socket.o
  CC      slirp/tcp_output.o
  CC      slirp/tcp_input.o
  CC      slirp/tcp_subr.o
  CC      slirp/tcp_timer.o
/tmp/qemu-test/src/slirp/tcp_input.c: In function ‘tcp_input’:
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_p’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_len’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_tos’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_id’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_off’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_ttl’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_sum’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_src.s_addr’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:219: warning: ‘save_ip.ip_dst.s_addr’ may be used uninitialized in this function
/tmp/qemu-test/src/slirp/tcp_input.c:220: warning: ‘save_ip6.ip_nh’ may be used uninitialized in this function
  CC      slirp/udp.o
  CC      slirp/udp6.o
  CC      slirp/bootp.o
  CC      slirp/tftp.o
  CC      slirp/arp_table.o
  CC      slirp/ncsi.o
  CC      slirp/ndp_table.o
  CC      ui/console.o
  CC      ui/keymaps.o
  CC      ui/qemu-pixman.o
  CC      ui/cursor.o
  CC      ui/input.o
  CC      ui/input-keymap.o
  CC      ui/input-legacy.o
  CC      ui/input-linux.o
  CC      ui/sdl.o
  CC      ui/x_keymap.o
  CC      ui/vnc.o
  CC      ui/sdl_zoom.o
  CC      ui/vnc-enc-zlib.o
  CC      ui/vnc-enc-hextile.o
  CC      ui/vnc-enc-tight.o
  CC      ui/vnc-palette.o
  CC      ui/vnc-enc-zrle.o
  CC      ui/vnc-auth-vencrypt.o
  CC      ui/vnc-ws.o
  CC      ui/vnc-jobs.o
  CC      chardev/char.o
  CC      chardev/char-fd.o
  CC      chardev/char-fe.o
  CC      chardev/char-file.o
  CC      chardev/char-io.o
  CC      chardev/char-mux.o
  CC      chardev/char-null.o
  CC      chardev/char-parallel.o
  CC      chardev/char-pipe.o
  CC      chardev/char-ringbuf.o
  CC      chardev/char-pty.o
  CC      chardev/char-serial.o
  CC      chardev/char-socket.o
  CC      chardev/char-stdio.o
  CC      chardev/char-udp.o
  LINK    tests/qemu-iotests/socket_scm_helper
  CC      qga/guest-agent-command-state.o
  CC      qga/commands.o
  CC      qga/main.o
  CC      qga/channel-posix.o
  CC      qga/commands-posix.o
  CC      qga/qapi-generated/qga-qmp-marshal.o
  CC      qga/qapi-generated/qga-qapi-types.o
  CC      qga/qapi-generated/qga-qapi-visit.o
  AR      libqemuutil.a
  AR      libqemustub.a
  CC      qemu-img.o
  AS      optionrom/linuxboot.o
  CC      optionrom/linuxboot_dma.o
  AS      optionrom/kvmvapic.o
  AS      optionrom/multiboot.o
cc: unrecognized option '-no-integrated-as'
cc: unrecognized option '-no-integrated-as'
  BUILD   optionrom/linuxboot_dma.img
  BUILD   optionrom/multiboot.img
  BUILD   optionrom/linuxboot.img
  BUILD   optionrom/linuxboot_dma.raw
  BUILD   optionrom/kvmvapic.img
  BUILD   optionrom/multiboot.raw
  BUILD   optionrom/linuxboot.raw
  BUILD   optionrom/kvmvapic.raw
  SIGN    optionrom/multiboot.bin
  SIGN    optionrom/linuxboot_dma.bin
  SIGN    optionrom/kvmvapic.bin
  LINK    qemu-ga
  SIGN    optionrom/linuxboot.bin
  LINK    ivshmem-client
  LINK    ivshmem-server
  LINK    qemu-nbd
  LINK    qemu-img
  LINK    qemu-io
  LINK    qemu-bridge-helper
  GEN     x86_64-softmmu/hmp-commands.h
  GEN     x86_64-softmmu/hmp-commands-info.h
  GEN     x86_64-softmmu/config-target.h
  GEN     aarch64-softmmu/hmp-commands.h
  GEN     aarch64-softmmu/config-target.h
  GEN     aarch64-softmmu/hmp-commands-info.h
  CC      x86_64-softmmu/tcg/tcg-op.o
  CC      x86_64-softmmu/exec.o
  CC      x86_64-softmmu/tcg/tcg.o
  CC      x86_64-softmmu/tcg/optimize.o
  CC      x86_64-softmmu/tcg/tcg-common.o
  CC      x86_64-softmmu/tcg/tcg-runtime.o
  CC      x86_64-softmmu/fpu/softfloat.o
  CC      x86_64-softmmu/disas.o
  GEN     x86_64-softmmu/gdbstub-xml.c
  CC      x86_64-softmmu/hax-stub.o
  CC      x86_64-softmmu/arch_init.o
  CC      x86_64-softmmu/cpus.o
  CC      x86_64-softmmu/gdbstub.o
  CC      x86_64-softmmu/monitor.o
  CC      x86_64-softmmu/balloon.o
  CC      x86_64-softmmu/numa.o
  CC      x86_64-softmmu/ioport.o
  CC      x86_64-softmmu/qtest.o
  CC      x86_64-softmmu/memory.o
  CC      x86_64-softmmu/memory_mapping.o
  CC      x86_64-softmmu/dump.o
  CC      x86_64-softmmu/migration/ram.o
  CC      x86_64-softmmu/accel/accel.o
  CC      x86_64-softmmu/accel/kvm/kvm-all.o
  CC      x86_64-softmmu/accel/tcg/tcg-all.o
  CC      aarch64-softmmu/exec.o
  CC      x86_64-softmmu/accel/tcg/cputlb.o
  CC      x86_64-softmmu/accel/tcg/cpu-exec.o
  CC      aarch64-softmmu/tcg/tcg.o
  CC      x86_64-softmmu/accel/tcg/translate-all.o
  CC      x86_64-softmmu/accel/tcg/cpu-exec-common.o
  CC      aarch64-softmmu/tcg/tcg-op.o
  CC      x86_64-softmmu/hw/block/virtio-blk.o
  CC      x86_64-softmmu/hw/block/dataplane/virtio-blk.o
  CC      x86_64-softmmu/hw/char/virtio-serial-bus.o
  CC      x86_64-softmmu/hw/core/generic-loader.o
  CC      x86_64-softmmu/hw/display/vga.o
  CC      x86_64-softmmu/hw/core/null-machine.o
  CC      x86_64-softmmu/hw/display/virtio-gpu.o
  CC      x86_64-softmmu/hw/display/virtio-gpu-3d.o
  CC      x86_64-softmmu/hw/display/virtio-gpu-pci.o
  CC      x86_64-softmmu/hw/display/virtio-vga.o
  CC      x86_64-softmmu/hw/intc/apic.o
  CC      x86_64-softmmu/hw/intc/ioapic.o
  CC      x86_64-softmmu/hw/intc/apic_common.o
  CC      x86_64-softmmu/hw/isa/lpc_ich9.o
  CC      x86_64-softmmu/hw/misc/vmport.o
  CC      x86_64-softmmu/hw/misc/ivshmem.o
  CC      x86_64-softmmu/hw/misc/pvpanic.o
  CC      x86_64-softmmu/hw/misc/hyperv_testdev.o
  CC      x86_64-softmmu/hw/misc/mmio_interface.o
  CC      x86_64-softmmu/hw/net/virtio-net.o
  CC      x86_64-softmmu/hw/net/vhost_net.o
  CC      aarch64-softmmu/tcg/optimize.o
  CC      aarch64-softmmu/tcg/tcg-common.o
  CC      x86_64-softmmu/hw/scsi/virtio-scsi.o
  CC      x86_64-softmmu/hw/scsi/virtio-scsi-dataplane.o
  CC      x86_64-softmmu/hw/scsi/vhost-scsi-common.o
  CC      aarch64-softmmu/tcg/tcg-runtime.o
  CC      x86_64-softmmu/hw/scsi/vhost-scsi.o
  CC      x86_64-softmmu/hw/scsi/vhost-user-scsi.o
  CC      x86_64-softmmu/hw/timer/mc146818rtc.o
  CC      x86_64-softmmu/hw/vfio/common.o
  CC      aarch64-softmmu/fpu/softfloat.o
  CC      aarch64-softmmu/disas.o
  GEN     aarch64-softmmu/gdbstub-xml.c
  CC      aarch64-softmmu/hax-stub.o
  CC      aarch64-softmmu/arch_init.o
  CC      aarch64-softmmu/cpus.o
  CC      x86_64-softmmu/hw/vfio/pci.o
  CC      x86_64-softmmu/hw/vfio/pci-quirks.o
  CC      aarch64-softmmu/monitor.o
  CC      x86_64-softmmu/hw/vfio/platform.o
  CC      aarch64-softmmu/gdbstub.o
  CC      aarch64-softmmu/balloon.o
  CC      aarch64-softmmu/ioport.o
  CC      aarch64-softmmu/qtest.o
  CC      aarch64-softmmu/numa.o
  CC      x86_64-softmmu/hw/vfio/spapr.o
  CC      x86_64-softmmu/hw/virtio/virtio.o
  CC      x86_64-softmmu/hw/virtio/virtio-balloon.o
  CC      x86_64-softmmu/hw/virtio/vhost.o
  CC      aarch64-softmmu/memory.o
  CC      x86_64-softmmu/hw/virtio/vhost-backend.o
  CC      x86_64-softmmu/hw/virtio/vhost-user.o
  CC      x86_64-softmmu/hw/virtio/vhost-vsock.o
  CC      x86_64-softmmu/hw/virtio/virtio-crypto.o
  CC      x86_64-softmmu/hw/virtio/virtio-crypto-pci.o
  CC      aarch64-softmmu/memory_mapping.o
  CC      x86_64-softmmu/hw/i386/multiboot.o
  CC      x86_64-softmmu/hw/i386/pc.o
  CC      aarch64-softmmu/dump.o
  CC      x86_64-softmmu/hw/i386/pc_piix.o
  CC      x86_64-softmmu/hw/i386/pc_q35.o
  CC      aarch64-softmmu/migration/ram.o
  CC      x86_64-softmmu/hw/i386/pc_sysfw.o
  CC      aarch64-softmmu/accel/accel.o
/tmp/qemu-test/src/hw/i386/pc_piix.c: In function ‘igd_passthrough_isa_bridge_create’:
/tmp/qemu-test/src/hw/i386/pc_piix.c:1065: warning: ‘pch_rev_id’ may be used uninitialized in this function
  CC      x86_64-softmmu/hw/i386/x86-iommu.o
  CC      x86_64-softmmu/hw/i386/intel_iommu.o
  CC      aarch64-softmmu/accel/stubs/kvm-stub.o
  CC      aarch64-softmmu/accel/tcg/tcg-all.o
  CC      aarch64-softmmu/accel/tcg/cputlb.o
  CC      aarch64-softmmu/accel/tcg/cpu-exec.o
  CC      aarch64-softmmu/accel/tcg/cpu-exec-common.o
  CC      aarch64-softmmu/accel/tcg/translate-all.o
  CC      x86_64-softmmu/hw/i386/amd_iommu.o
  CC      aarch64-softmmu/hw/adc/stm32f2xx_adc.o
  CC      aarch64-softmmu/hw/block/virtio-blk.o
  CC      aarch64-softmmu/hw/block/dataplane/virtio-blk.o
  CC      x86_64-softmmu/hw/i386/kvmvapic.o
  CC      aarch64-softmmu/hw/char/exynos4210_uart.o
  CC      x86_64-softmmu/hw/i386/acpi-build.o
  CC      x86_64-softmmu/hw/i386/pci-assign-load-rom.o
/tmp/qemu-test/src/hw/i386/acpi-build.c: In function ‘build_append_pci_bus_devices’:
/tmp/qemu-test/src/hw/i386/acpi-build.c:525: warning: ‘notify_method’ may be used uninitialized in this function
  CC      x86_64-softmmu/hw/i386/kvm/clock.o
  CC      aarch64-softmmu/hw/char/omap_uart.o
  CC      aarch64-softmmu/hw/char/digic-uart.o
  CC      x86_64-softmmu/hw/i386/kvm/apic.o
  CC      x86_64-softmmu/hw/i386/kvm/i8259.o
  CC      aarch64-softmmu/hw/char/stm32f2xx_usart.o
  CC      x86_64-softmmu/hw/i386/kvm/ioapic.o
  CC      aarch64-softmmu/hw/char/bcm2835_aux.o
  CC      aarch64-softmmu/hw/char/virtio-serial-bus.o
  CC      aarch64-softmmu/hw/core/generic-loader.o
  CC      aarch64-softmmu/hw/core/null-machine.o
  CC      x86_64-softmmu/hw/i386/kvm/i8254.o
  CC      x86_64-softmmu/hw/i386/kvm/pci-assign.o
  CC      x86_64-softmmu/target/i386/helper.o
  CC      x86_64-softmmu/target/i386/cpu.o
  CC      x86_64-softmmu/target/i386/gdbstub.o
  CC      x86_64-softmmu/target/i386/xsave_helper.o
  CC      x86_64-softmmu/target/i386/translate.o
  CC      x86_64-softmmu/target/i386/bpt_helper.o
  CC      x86_64-softmmu/target/i386/cc_helper.o
  CC      x86_64-softmmu/target/i386/excp_helper.o
  CC      x86_64-softmmu/target/i386/fpu_helper.o
  CC      aarch64-softmmu/hw/cpu/arm11mpcore.o
  CC      x86_64-softmmu/target/i386/int_helper.o
  CC      x86_64-softmmu/target/i386/mem_helper.o
  CC      aarch64-softmmu/hw/cpu/realview_mpcore.o
  CC      x86_64-softmmu/target/i386/misc_helper.o
  CC      aarch64-softmmu/hw/cpu/a9mpcore.o
  CC      x86_64-softmmu/target/i386/mpx_helper.o
  CC      aarch64-softmmu/hw/cpu/a15mpcore.o
  CC      aarch64-softmmu/hw/display/omap_dss.o
  CC      aarch64-softmmu/hw/display/omap_lcdc.o
  CC      x86_64-softmmu/target/i386/seg_helper.o
  CC      x86_64-softmmu/target/i386/smm_helper.o
  CC      aarch64-softmmu/hw/display/pxa2xx_lcd.o
  CC      x86_64-softmmu/target/i386/svm_helper.o
  CC      aarch64-softmmu/hw/display/bcm2835_fb.o
  CC      x86_64-softmmu/target/i386/machine.o
  CC      aarch64-softmmu/hw/display/vga.o
  CC      x86_64-softmmu/target/i386/arch_memory_mapping.o
  CC      x86_64-softmmu/target/i386/arch_dump.o
  CC      aarch64-softmmu/hw/display/virtio-gpu.o
  CC      aarch64-softmmu/hw/display/virtio-gpu-3d.o
  CC      x86_64-softmmu/target/i386/monitor.o
  CC      x86_64-softmmu/target/i386/kvm.o
  CC      x86_64-softmmu/target/i386/hyperv.o
  CC      aarch64-softmmu/hw/display/virtio-gpu-pci.o
  GEN     trace/generated-helpers.c
  CC      aarch64-softmmu/hw/display/dpcd.o
  CC      x86_64-softmmu/trace/control-target.o
  CC      aarch64-softmmu/hw/display/xlnx_dp.o
  CC      aarch64-softmmu/hw/dma/xlnx_dpdma.o
  CC      x86_64-softmmu/gdbstub-xml.o
  CC      aarch64-softmmu/hw/dma/omap_dma.o
  CC      aarch64-softmmu/hw/dma/pxa2xx_dma.o
  CC      aarch64-softmmu/hw/dma/soc_dma.o
  CC      aarch64-softmmu/hw/dma/bcm2835_dma.o
  CC      x86_64-softmmu/trace/generated-helpers.o
  CC      aarch64-softmmu/hw/gpio/omap_gpio.o
  CC      aarch64-softmmu/hw/gpio/imx_gpio.o
  CC      aarch64-softmmu/hw/gpio/bcm2835_gpio.o
  CC      aarch64-softmmu/hw/i2c/omap_i2c.o
  CC      aarch64-softmmu/hw/input/pxa2xx_keypad.o
  CC      aarch64-softmmu/hw/input/tsc210x.o
  LINK    x86_64-softmmu/qemu-system-x86_64
  CC      aarch64-softmmu/hw/intc/armv7m_nvic.o
  CC      aarch64-softmmu/hw/intc/exynos4210_gic.o
  CC      aarch64-softmmu/hw/intc/exynos4210_combiner.o
  CC      aarch64-softmmu/hw/intc/omap_intc.o
  CC      aarch64-softmmu/hw/intc/bcm2835_ic.o
  CC      aarch64-softmmu/hw/intc/bcm2836_control.o
  CC      aarch64-softmmu/hw/intc/allwinner-a10-pic.o
  CC      aarch64-softmmu/hw/intc/aspeed_vic.o
  CC      aarch64-softmmu/hw/intc/arm_gicv3_cpuif.o
  CC      aarch64-softmmu/hw/misc/ivshmem.o
  CC      aarch64-softmmu/hw/misc/arm_sysctl.o
  CC      aarch64-softmmu/hw/misc/cbus.o
  CC      aarch64-softmmu/hw/misc/exynos4210_pmu.o
  CC      aarch64-softmmu/hw/misc/exynos4210_clk.o
  CC      aarch64-softmmu/hw/misc/exynos4210_rng.o
  CC      aarch64-softmmu/hw/misc/imx_ccm.o
  CC      aarch64-softmmu/hw/misc/imx31_ccm.o
  CC      aarch64-softmmu/hw/misc/imx25_ccm.o
  CC      aarch64-softmmu/hw/misc/imx6_ccm.o
  CC      aarch64-softmmu/hw/misc/imx6_src.o
  CC      aarch64-softmmu/hw/misc/mst_fpga.o
  CC      aarch64-softmmu/hw/misc/omap_clk.o
  CC      aarch64-softmmu/hw/misc/omap_gpmc.o
  CC      aarch64-softmmu/hw/misc/omap_l4.o
  CC      aarch64-softmmu/hw/misc/omap_sdrc.o
  CC      aarch64-softmmu/hw/misc/omap_tap.o
  CC      aarch64-softmmu/hw/misc/bcm2835_mbox.o
  CC      aarch64-softmmu/hw/misc/bcm2835_property.o
  CC      aarch64-softmmu/hw/misc/bcm2835_rng.o
  CC      aarch64-softmmu/hw/misc/zynq_slcr.o
  CC      aarch64-softmmu/hw/misc/zynq-xadc.o
  CC      aarch64-softmmu/hw/misc/stm32f2xx_syscfg.o
  CC      aarch64-softmmu/hw/misc/mps2-scc.o
  CC      aarch64-softmmu/hw/misc/auxbus.o
  CC      aarch64-softmmu/hw/misc/aspeed_scu.o
  CC      aarch64-softmmu/hw/misc/aspeed_sdmc.o
  CC      aarch64-softmmu/hw/misc/mmio_interface.o
  CC      aarch64-softmmu/hw/net/virtio-net.o
  CC      aarch64-softmmu/hw/net/vhost_net.o
  CC      aarch64-softmmu/hw/pcmcia/pxa2xx.o
  CC      aarch64-softmmu/hw/scsi/virtio-scsi.o
  CC      aarch64-softmmu/hw/scsi/virtio-scsi-dataplane.o
  CC      aarch64-softmmu/hw/scsi/vhost-scsi-common.o
  CC      aarch64-softmmu/hw/scsi/vhost-user-scsi.o
  CC      aarch64-softmmu/hw/scsi/vhost-scsi.o
  CC      aarch64-softmmu/hw/sd/omap_mmc.o
  CC      aarch64-softmmu/hw/sd/pxa2xx_mmci.o
  CC      aarch64-softmmu/hw/sd/bcm2835_sdhost.o
  CC      aarch64-softmmu/hw/ssi/omap_spi.o
  CC      aarch64-softmmu/hw/ssi/imx_spi.o
  CC      aarch64-softmmu/hw/timer/exynos4210_mct.o
  CC      aarch64-softmmu/hw/timer/exynos4210_pwm.o
  CC      aarch64-softmmu/hw/timer/exynos4210_rtc.o
  CC      aarch64-softmmu/hw/timer/omap_gptimer.o
  CC      aarch64-softmmu/hw/timer/omap_synctimer.o
  CC      aarch64-softmmu/hw/timer/pxa2xx_timer.o
  CC      aarch64-softmmu/hw/timer/digic-timer.o
  CC      aarch64-softmmu/hw/timer/allwinner-a10-pit.o
  CC      aarch64-softmmu/hw/usb/tusb6010.o
  CC      aarch64-softmmu/hw/vfio/pci.o
  CC      aarch64-softmmu/hw/vfio/pci-quirks.o
  CC      aarch64-softmmu/hw/vfio/common.o
  CC      aarch64-softmmu/hw/vfio/platform.o
  CC      aarch64-softmmu/hw/vfio/calxeda-xgmac.o
  CC      aarch64-softmmu/hw/vfio/amd-xgbe.o
  CC      aarch64-softmmu/hw/vfio/spapr.o
  CC      aarch64-softmmu/hw/virtio/virtio.o
  CC      aarch64-softmmu/hw/virtio/virtio-balloon.o
  CC      aarch64-softmmu/hw/virtio/vhost.o
  CC      aarch64-softmmu/hw/virtio/vhost-backend.o
  CC      aarch64-softmmu/hw/virtio/vhost-user.o
  CC      aarch64-softmmu/hw/virtio/vhost-vsock.o
  CC      aarch64-softmmu/hw/virtio/virtio-crypto.o
  CC      aarch64-softmmu/hw/virtio/virtio-crypto-pci.o
  CC      aarch64-softmmu/hw/arm/boot.o
  CC      aarch64-softmmu/hw/arm/collie.o
  CC      aarch64-softmmu/hw/arm/exynos4_boards.o
  CC      aarch64-softmmu/hw/arm/gumstix.o
  CC      aarch64-softmmu/hw/arm/highbank.o
  CC      aarch64-softmmu/hw/arm/digic_boards.o
  CC      aarch64-softmmu/hw/arm/integratorcp.o
  CC      aarch64-softmmu/hw/arm/mainstone.o
  CC      aarch64-softmmu/hw/arm/musicpal.o
  CC      aarch64-softmmu/hw/arm/nseries.o
  CC      aarch64-softmmu/hw/arm/omap_sx1.o
  CC      aarch64-softmmu/hw/arm/palm.o
  CC      aarch64-softmmu/hw/arm/realview.o
  CC      aarch64-softmmu/hw/arm/spitz.o
  CC      aarch64-softmmu/hw/arm/stellaris.o
  CC      aarch64-softmmu/hw/arm/tosa.o
  CC      aarch64-softmmu/hw/arm/versatilepb.o
  CC      aarch64-softmmu/hw/arm/vexpress.o
  CC      aarch64-softmmu/hw/arm/virt.o
  CC      aarch64-softmmu/hw/arm/xilinx_zynq.o
  CC      aarch64-softmmu/hw/arm/z2.o
  CC      aarch64-softmmu/hw/arm/virt-acpi-build.o
  CC      aarch64-softmmu/hw/arm/netduino2.o
  CC      aarch64-softmmu/hw/arm/sysbus-fdt.o
  CC      aarch64-softmmu/hw/arm/armv7m.o
  CC      aarch64-softmmu/hw/arm/exynos4210.o
  CC      aarch64-softmmu/hw/arm/pxa2xx.o
  CC      aarch64-softmmu/hw/arm/pxa2xx_gpio.o
  CC      aarch64-softmmu/hw/arm/pxa2xx_pic.o
  CC      aarch64-softmmu/hw/arm/digic.o
  CC      aarch64-softmmu/hw/arm/omap1.o
  CC      aarch64-softmmu/hw/arm/omap2.o
  CC      aarch64-softmmu/hw/arm/strongarm.o
  CC      aarch64-softmmu/hw/arm/allwinner-a10.o
  CC      aarch64-softmmu/hw/arm/cubieboard.o
  CC      aarch64-softmmu/hw/arm/bcm2835_peripherals.o
  CC      aarch64-softmmu/hw/arm/bcm2836.o
  CC      aarch64-softmmu/hw/arm/raspi.o
  CC      aarch64-softmmu/hw/arm/xlnx-zynqmp.o
  CC      aarch64-softmmu/hw/arm/stm32f205_soc.o
  CC      aarch64-softmmu/hw/arm/xlnx-ep108.o
  CC      aarch64-softmmu/hw/arm/fsl-imx25.o
  CC      aarch64-softmmu/hw/arm/imx25_pdk.o
  CC      aarch64-softmmu/hw/arm/fsl-imx31.o
  CC      aarch64-softmmu/hw/arm/kzm.o
  CC      aarch64-softmmu/hw/arm/fsl-imx6.o
  CC      aarch64-softmmu/hw/arm/sabrelite.o
  CC      aarch64-softmmu/hw/arm/aspeed_soc.o
  CC      aarch64-softmmu/hw/arm/aspeed.o
  CC      aarch64-softmmu/hw/arm/mps2.o
  CC      aarch64-softmmu/target/arm/arm-semi.o
  CC      aarch64-softmmu/target/arm/machine.o
  CC      aarch64-softmmu/target/arm/psci.o
  CC      aarch64-softmmu/target/arm/arch_dump.o
  CC      aarch64-softmmu/target/arm/monitor.o
  CC      aarch64-softmmu/target/arm/kvm-stub.o
  CC      aarch64-softmmu/target/arm/translate.o
  CC      aarch64-softmmu/target/arm/op_helper.o
  CC      aarch64-softmmu/target/arm/helper.o
  CC      aarch64-softmmu/target/arm/cpu.o
  CC      aarch64-softmmu/target/arm/neon_helper.o
  CC      aarch64-softmmu/target/arm/iwmmxt_helper.o
  CC      aarch64-softmmu/target/arm/gdbstub.o
  CC      aarch64-softmmu/target/arm/cpu64.o
  CC      aarch64-softmmu/target/arm/translate-a64.o
  CC      aarch64-softmmu/target/arm/helper-a64.o
  CC      aarch64-softmmu/target/arm/gdbstub64.o
/tmp/qemu-test/src/target/arm/translate-a64.c: In function ‘handle_shri_with_rndacc’:
/tmp/qemu-test/src/target/arm/translate-a64.c:6368: warning: ‘tcg_src_hi’ may be used uninitialized in this function
/tmp/qemu-test/src/target/arm/translate-a64.c: In function ‘disas_simd_scalar_two_reg_misc’:
/tmp/qemu-test/src/target/arm/translate-a64.c:8095: warning: ‘rmode’ may be used uninitialized in this function
  CC      aarch64-softmmu/target/arm/crypto_helper.o
  CC      aarch64-softmmu/target/arm/arm-powerctl.o
  GEN     trace/generated-helpers.c
  CC      aarch64-softmmu/trace/control-target.o
  CC      aarch64-softmmu/gdbstub-xml.o
  CC      aarch64-softmmu/trace/generated-helpers.o
  LINK    aarch64-softmmu/qemu-system-aarch64
  TEST    tests/qapi-schema/alternate-any.out
  TEST    tests/qapi-schema/alternate-array.out
  TEST    tests/qapi-schema/alternate-base.out
  TEST    tests/qapi-schema/alternate-clash.out
  TEST    tests/qapi-schema/alternate-conflict-dict.out
  TEST    tests/qapi-schema/alternate-conflict-enum-bool.out
  TEST    tests/qapi-schema/alternate-conflict-enum-int.out
  TEST    tests/qapi-schema/alternate-conflict-string.out
  TEST    tests/qapi-schema/alternate-empty.out
  TEST    tests/qapi-schema/alternate-nested.out
  TEST    tests/qapi-schema/alternate-unknown.out
  TEST    tests/qapi-schema/args-alternate.out
  TEST    tests/qapi-schema/args-any.out
  TEST    tests/qapi-schema/args-array-empty.out
  TEST    tests/qapi-schema/args-array-unknown.out
  TEST    tests/qapi-schema/args-bad-boxed.out
  TEST    tests/qapi-schema/args-boxed-anon.out
  TEST    tests/qapi-schema/args-boxed-empty.out
  TEST    tests/qapi-schema/args-boxed-string.out
  TEST    tests/qapi-schema/args-invalid.out
  TEST    tests/qapi-schema/args-int.out
  TEST    tests/qapi-schema/args-member-array-bad.out
  TEST    tests/qapi-schema/args-member-case.out
  TEST    tests/qapi-schema/args-member-unknown.out
  TEST    tests/qapi-schema/args-name-clash.out
  TEST    tests/qapi-schema/args-union.out
  TEST    tests/qapi-schema/args-unknown.out
  TEST    tests/qapi-schema/bad-base.out
  TEST    tests/qapi-schema/bad-data.out
  TEST    tests/qapi-schema/bad-ident.out
  TEST    tests/qapi-schema/bad-type-bool.out
  TEST    tests/qapi-schema/bad-type-dict.out
  TEST    tests/qapi-schema/bad-type-int.out
  TEST    tests/qapi-schema/base-cycle-direct.out
  TEST    tests/qapi-schema/base-cycle-indirect.out
  TEST    tests/qapi-schema/command-int.out
  TEST    tests/qapi-schema/comments.out
  TEST    tests/qapi-schema/doc-bad-alternate-member.out
  TEST    tests/qapi-schema/doc-bad-command-arg.out
  TEST    tests/qapi-schema/doc-bad-symbol.out
  TEST    tests/qapi-schema/doc-bad-union-member.out
  TEST    tests/qapi-schema/doc-before-include.out
  TEST    tests/qapi-schema/doc-before-pragma.out
  TEST    tests/qapi-schema/doc-duplicated-arg.out
  TEST    tests/qapi-schema/doc-duplicated-return.out
  TEST    tests/qapi-schema/doc-duplicated-since.out
  TEST    tests/qapi-schema/doc-empty-arg.out
  TEST    tests/qapi-schema/doc-empty-section.out
  TEST    tests/qapi-schema/doc-empty-symbol.out
  TEST    tests/qapi-schema/doc-good.out
  TEST    tests/qapi-schema/doc-interleaved-section.out
  TEST    tests/qapi-schema/doc-invalid-end.out
  TEST    tests/qapi-schema/doc-invalid-end2.out
  TEST    tests/qapi-schema/doc-invalid-return.out
  TEST    tests/qapi-schema/doc-invalid-section.out
  TEST    tests/qapi-schema/doc-invalid-start.out
  TEST    tests/qapi-schema/doc-missing.out
  TEST    tests/qapi-schema/doc-missing-colon.out
  TEST    tests/qapi-schema/doc-missing-expr.out
  TEST    tests/qapi-schema/doc-missing-space.out
  TEST    tests/qapi-schema/doc-no-symbol.out
  TEST    tests/qapi-schema/double-data.out
  TEST    tests/qapi-schema/double-type.out
  TEST    tests/qapi-schema/duplicate-key.out
  TEST    tests/qapi-schema/empty.out
  TEST    tests/qapi-schema/enum-bad-name.out
  TEST    tests/qapi-schema/enum-bad-prefix.out
  TEST    tests/qapi-schema/enum-clash-member.out
  TEST    tests/qapi-schema/enum-dict-member.out
  TEST    tests/qapi-schema/enum-int-member.out
  TEST    tests/qapi-schema/enum-member-case.out
  TEST    tests/qapi-schema/enum-missing-data.out
  TEST    tests/qapi-schema/enum-wrong-data.out
  TEST    tests/qapi-schema/escape-outside-string.out
  TEST    tests/qapi-schema/escape-too-big.out
  TEST    tests/qapi-schema/escape-too-short.out
  TEST    tests/qapi-schema/event-boxed-empty.out
  TEST    tests/qapi-schema/event-case.out
  TEST    tests/qapi-schema/event-nest-struct.out
  TEST    tests/qapi-schema/flat-union-array-branch.out
  TEST    tests/qapi-schema/flat-union-bad-base.out
  TEST    tests/qapi-schema/flat-union-bad-discriminator.out
  TEST    tests/qapi-schema/flat-union-base-any.out
  TEST    tests/qapi-schema/flat-union-base-union.out
  TEST    tests/qapi-schema/flat-union-clash-member.out
  TEST    tests/qapi-schema/flat-union-empty.out
  TEST    tests/qapi-schema/flat-union-incomplete-branch.out
  TEST    tests/qapi-schema/flat-union-inline.out
  TEST    tests/qapi-schema/flat-union-int-branch.out
  TEST    tests/qapi-schema/flat-union-invalid-branch-key.out
  TEST    tests/qapi-schema/flat-union-invalid-discriminator.out
  TEST    tests/qapi-schema/flat-union-no-base.out
  TEST    tests/qapi-schema/flat-union-optional-discriminator.out
  TEST    tests/qapi-schema/flat-union-string-discriminator.out
  TEST    tests/qapi-schema/funny-char.out
  TEST    tests/qapi-schema/ident-with-escape.out
  TEST    tests/qapi-schema/include-before-err.out
  TEST    tests/qapi-schema/include-cycle.out
  TEST    tests/qapi-schema/include-extra-junk.out
  TEST    tests/qapi-schema/include-format-err.out
  TEST    tests/qapi-schema/include-nested-err.out
  TEST    tests/qapi-schema/include-no-file.out
  TEST    tests/qapi-schema/include-non-file.out
  TEST    tests/qapi-schema/include-relpath.out
  TEST    tests/qapi-schema/include-repetition.out
  TEST    tests/qapi-schema/include-self-cycle.out
  TEST    tests/qapi-schema/include-simple.out
  TEST    tests/qapi-schema/indented-expr.out
  TEST    tests/qapi-schema/leading-comma-object.out
  TEST    tests/qapi-schema/leading-comma-list.out
  TEST    tests/qapi-schema/missing-comma-list.out
  TEST    tests/qapi-schema/missing-colon.out
  TEST    tests/qapi-schema/missing-comma-object.out
  TEST    tests/qapi-schema/missing-type.out
  TEST    tests/qapi-schema/nested-struct-data.out
  TEST    tests/qapi-schema/non-objects.out
  TEST    tests/qapi-schema/pragma-doc-required-crap.out
  TEST    tests/qapi-schema/pragma-extra-junk.out
  TEST    tests/qapi-schema/pragma-name-case-whitelist-crap.out
  TEST    tests/qapi-schema/pragma-non-dict.out
  TEST    tests/qapi-schema/pragma-returns-whitelist-crap.out
  TEST    tests/qapi-schema/qapi-schema-test.out
  TEST    tests/qapi-schema/quoted-structural-chars.out
  TEST    tests/qapi-schema/redefined-builtin.out
  TEST    tests/qapi-schema/redefined-command.out
  TEST    tests/qapi-schema/redefined-event.out
  TEST    tests/qapi-schema/redefined-type.out
  TEST    tests/qapi-schema/reserved-command-q.out
  TEST    tests/qapi-schema/reserved-enum-q.out
  TEST    tests/qapi-schema/reserved-member-has.out
  TEST    tests/qapi-schema/reserved-member-q.out
  TEST    tests/qapi-schema/reserved-member-u.out
  TEST    tests/qapi-schema/reserved-member-underscore.out
  TEST    tests/qapi-schema/reserved-type-kind.out
  TEST    tests/qapi-schema/reserved-type-list.out
  TEST    tests/qapi-schema/returns-alternate.out
  TEST    tests/qapi-schema/returns-array-bad.out
  TEST    tests/qapi-schema/returns-dict.out
  TEST    tests/qapi-schema/returns-unknown.out
  TEST    tests/qapi-schema/returns-whitelist.out
  TEST    tests/qapi-schema/struct-base-clash-deep.out
  TEST    tests/qapi-schema/struct-base-clash.out
  TEST    tests/qapi-schema/struct-data-invalid.out
  TEST    tests/qapi-schema/struct-member-invalid.out
  TEST    tests/qapi-schema/trailing-comma-list.out
  TEST    tests/qapi-schema/trailing-comma-object.out
  TEST    tests/qapi-schema/type-bypass-bad-gen.out
  TEST    tests/qapi-schema/unclosed-list.out
  TEST    tests/qapi-schema/unclosed-object.out
  TEST    tests/qapi-schema/unclosed-string.out
  TEST    tests/qapi-schema/unicode-str.out
  TEST    tests/qapi-schema/union-base-empty.out
  TEST    tests/qapi-schema/union-base-no-discriminator.out
  TEST    tests/qapi-schema/union-branch-case.out
  TEST    tests/qapi-schema/union-clash-branches.out
  TEST    tests/qapi-schema/union-empty.out
  TEST    tests/qapi-schema/union-invalid-base.out
  TEST    tests/qapi-schema/union-optional-branch.out
  TEST    tests/qapi-schema/union-unknown.out
  TEST    tests/qapi-schema/unknown-escape.out
  TEST    tests/qapi-schema/unknown-expr-key.out
  GEN     tests/qapi-schema/doc-good.test.texi
  CC      tests/check-qdict.o
  CC      tests/test-char.o
  CC      tests/check-qnum.o
  CC      tests/check-qstring.o
  CC      tests/check-qlist.o
  CC      tests/check-qnull.o
  CC      tests/check-qjson.o
  CC      tests/test-qobject-output-visitor.o
  GEN     tests/test-qapi-visit.c
  GEN     tests/test-qapi-event.c
  GEN     tests/test-qmp-introspect.c
  CC      tests/test-clone-visitor.o
  GEN     tests/test-qapi-types.c
  CC      tests/test-qobject-input-visitor.o
  CC      tests/test-qmp-commands.o
  GEN     tests/test-qmp-marshal.c
  CC      tests/test-string-input-visitor.o
  CC      tests/test-string-output-visitor.o
  CC      tests/test-qmp-event.o
  CC      tests/test-opts-visitor.o
  CC      tests/test-coroutine.o
  CC      tests/test-visitor-serialization.o
  CC      tests/test-iov.o
  CC      tests/iothread.o
  CC      tests/test-aio.o
  CC      tests/test-aio-multithread.o
  CC      tests/test-throttle.o
  CC      tests/test-thread-pool.o
  CC      tests/test-hbitmap.o
  CC      tests/test-blockjob.o
  CC      tests/test-blockjob-txn.o
  CC      tests/test-x86-cpuid.o
  CC      tests/test-xbzrle.o
  CC      tests/test-vmstate.o
  CC      tests/test-cutils.o
  CC      tests/test-shift128.o
  CC      tests/test-mul64.o
  CC      tests/test-int128.o
  CC      tests/rcutorture.o
  CC      tests/test-rcu-list.o
  CC      tests/test-qht.o
  CC      tests/test-qht-par.o
  CC      tests/test-qdist.o
/tmp/qemu-test/src/tests/test-int128.c:180: warning: ‘__noclone__’ attribute directive ignored
  CC      tests/qht-bench.o
  CC      tests/test-bitops.o
  CC      tests/test-bitcnt.o
  CC      tests/check-qom-interface.o
  CC      tests/check-qom-proplist.o
  CC      tests/test-qemu-opts.o
  CC      tests/test-keyval.o
  CC      tests/test-write-threshold.o
  CC      tests/test-crypto-hash.o
  CC      tests/test-crypto-hmac.o
  CC      tests/test-crypto-cipher.o
  CC      tests/test-crypto-secret.o
  CC      tests/test-qga.o
  CC      tests/libqtest.o
  CC      tests/test-timed-average.o
  CC      tests/test-io-task.o
  CC      tests/test-io-channel-socket.o
  CC      tests/io-channel-helpers.o
  CC      tests/test-io-channel-file.o
  CC      tests/test-io-channel-command.o
  CC      tests/test-io-channel-buffer.o
  CC      tests/test-base64.o
  CC      tests/test-crypto-ivgen.o
  CC      tests/test-crypto-afsplit.o
  CC      tests/test-crypto-xts.o
  CC      tests/test-crypto-block.o
  CC      tests/test-logging.o
  CC      tests/test-replication.o
  CC      tests/test-bufferiszero.o
  CC      tests/test-uuid.o
  CC      tests/ptimer-test-stubs.o
  CC      tests/ptimer-test.o
  CC      tests/test-qapi-util.o
  CC      tests/vhost-user-test.o
  CC      tests/libqos/pci.o
  CC      tests/libqos/fw_cfg.o
  CC      tests/libqos/malloc.o
  CC      tests/libqos/i2c.o
  CC      tests/libqos/libqos.o
  CC      tests/libqos/malloc-spapr.o
  CC      tests/libqos/libqos-spapr.o
  CC      tests/libqos/rtas.o
  CC      tests/libqos/pci-spapr.o
  CC      tests/libqos/pci-pc.o
  CC      tests/libqos/malloc-pc.o
  CC      tests/libqos/libqos-pc.o
  CC      tests/libqos/ahci.o
  CC      tests/libqos/virtio.o
  CC      tests/libqos/virtio-pci.o
  CC      tests/libqos/virtio-mmio.o
  CC      tests/libqos/malloc-generic.o
  CC      tests/endianness-test.o
  CC      tests/fdc-test.o
  CC      tests/ide-test.o
  CC      tests/ahci-test.o
  CC      tests/hd-geo-test.o
  CC      tests/boot-order-test.o
  CC      tests/bios-tables-test.o
  CC      tests/boot-sector.o
  CC      tests/acpi-utils.o
  CC      tests/boot-serial-test.o
  CC      tests/pxe-test.o
  CC      tests/rtc-test.o
  CC      tests/ipmi-kcs-test.o
  CC      tests/ipmi-bt-test.o
  CC      tests/i440fx-test.o
  CC      tests/fw_cfg-test.o
  CC      tests/drive_del-test.o
  CC      tests/wdt_ib700-test.o
  CC      tests/tco-test.o
  CC      tests/e1000-test.o
  CC      tests/e1000e-test.o
  CC      tests/rtl8139-test.o
  CC      tests/pcnet-test.o
  CC      tests/eepro100-test.o
  CC      tests/ne2000-test.o
  CC      tests/nvme-test.o
  CC      tests/ac97-test.o
  CC      tests/es1370-test.o
  CC      tests/virtio-net-test.o
  CC      tests/virtio-balloon-test.o
  CC      tests/virtio-blk-test.o
  CC      tests/virtio-rng-test.o
  CC      tests/virtio-scsi-test.o
  CC      tests/virtio-serial-test.o
  CC      tests/virtio-console-test.o
  CC      tests/tpci200-test.o
  CC      tests/ipoctal232-test.o
  CC      tests/display-vga-test.o
  CC      tests/intel-hda-test.o
  CC      tests/ivshmem-test.o
  CC      tests/megasas-test.o
  CC      tests/vmxnet3-test.o
  CC      tests/pvpanic-test.o
  CC      tests/i82801b11-test.o
  CC      tests/ioh3420-test.o
  CC      tests/usb-hcd-ohci-test.o
  CC      tests/libqos/usb.o
  CC      tests/usb-hcd-uhci-test.o
  CC      tests/usb-hcd-ehci-test.o
  CC      tests/usb-hcd-xhci-test.o
  CC      tests/pc-cpu-test.o
  CC      tests/q35-test.o
  CC      tests/vmgenid-test.o
  CC      tests/test-netfilter.o
  CC      tests/test-filter-mirror.o
  CC      tests/test-filter-redirector.o
  CC      tests/postcopy-test.o
  CC      tests/test-x86-cpuid-compat.o
  CC      tests/numa-test.o
  CC      tests/qmp-test.o
  CC      tests/device-introspect-test.o
  CC      tests/qom-test.o
  CC      tests/test-hmp.o
  LINK    tests/check-qdict
  LINK    tests/test-char
  LINK    tests/check-qnum
  LINK    tests/check-qstring
  LINK    tests/check-qlist
  LINK    tests/check-qnull
  CC      tests/test-qapi-visit.o
  CC      tests/test-qapi-event.o
  CC      tests/test-qapi-types.o
  CC      tests/test-qmp-introspect.o
  LINK    tests/check-qjson
  CC      tests/test-qmp-marshal.o
  LINK    tests/test-coroutine
  LINK    tests/test-visitor-serialization
  LINK    tests/test-iov
  LINK    tests/test-aio
  LINK    tests/test-aio-multithread
  LINK    tests/test-throttle
  LINK    tests/test-thread-pool
  LINK    tests/test-hbitmap
  LINK    tests/test-blockjob
  LINK    tests/test-blockjob-txn
  LINK    tests/test-x86-cpuid
  LINK    tests/test-xbzrle
  LINK    tests/test-vmstate
  LINK    tests/test-cutils
  LINK    tests/test-shift128
  LINK    tests/test-mul64
  LINK    tests/test-int128
  LINK    tests/rcutorture
  LINK    tests/test-rcu-list
  LINK    tests/test-qdist
  LINK    tests/test-qht
  LINK    tests/qht-bench
  LINK    tests/test-bitops
  LINK    tests/test-bitcnt
  LINK    tests/check-qom-interface
  LINK    tests/check-qom-proplist
  LINK    tests/test-qemu-opts
  LINK    tests/test-keyval
  LINK    tests/test-write-threshold
  LINK    tests/test-crypto-hash
  LINK    tests/test-crypto-hmac
  LINK    tests/test-crypto-cipher
  LINK    tests/test-crypto-secret
  LINK    tests/test-qga
  LINK    tests/test-timed-average
  LINK    tests/test-io-task
  LINK    tests/test-io-channel-socket
  LINK    tests/test-io-channel-file
  LINK    tests/test-io-channel-command
  LINK    tests/test-io-channel-buffer
  LINK    tests/test-base64
  LINK    tests/test-crypto-ivgen
  LINK    tests/test-crypto-afsplit
  LINK    tests/test-crypto-xts
  LINK    tests/test-crypto-block
  LINK    tests/test-logging
  LINK    tests/test-replication
  LINK    tests/test-bufferiszero
  LINK    tests/test-uuid
  LINK    tests/ptimer-test
  LINK    tests/test-qapi-util
  LINK    tests/vhost-user-test
  LINK    tests/endianness-test
  LINK    tests/fdc-test
  LINK    tests/ide-test
  LINK    tests/ahci-test
  LINK    tests/hd-geo-test
  LINK    tests/boot-order-test
  LINK    tests/bios-tables-test
  LINK    tests/boot-serial-test
  LINK    tests/pxe-test
  LINK    tests/rtc-test
  LINK    tests/ipmi-kcs-test
  LINK    tests/ipmi-bt-test
  LINK    tests/i440fx-test
  LINK    tests/fw_cfg-test
  LINK    tests/drive_del-test
  LINK    tests/wdt_ib700-test
  LINK    tests/tco-test
  LINK    tests/e1000-test
  LINK    tests/e1000e-test
  LINK    tests/rtl8139-test
  LINK    tests/pcnet-test
  LINK    tests/eepro100-test
  LINK    tests/ne2000-test
  LINK    tests/nvme-test
  LINK    tests/ac97-test
  LINK    tests/es1370-test
  LINK    tests/virtio-net-test
  LINK    tests/virtio-balloon-test
  LINK    tests/virtio-blk-test
  LINK    tests/virtio-rng-test
  LINK    tests/virtio-scsi-test
  LINK    tests/virtio-serial-test
  LINK    tests/virtio-console-test
  LINK    tests/tpci200-test
  LINK    tests/ipoctal232-test
  LINK    tests/display-vga-test
  LINK    tests/intel-hda-test
  LINK    tests/ivshmem-test
  LINK    tests/megasas-test
  LINK    tests/vmxnet3-test
  LINK    tests/pvpanic-test
  LINK    tests/i82801b11-test
  LINK    tests/ioh3420-test
  LINK    tests/usb-hcd-ohci-test
  LINK    tests/usb-hcd-uhci-test
  LINK    tests/usb-hcd-ehci-test
  LINK    tests/usb-hcd-xhci-test
  LINK    tests/pc-cpu-test
  LINK    tests/q35-test
  LINK    tests/vmgenid-test
  LINK    tests/test-netfilter
  LINK    tests/test-filter-mirror
  LINK    tests/test-filter-redirector
  LINK    tests/postcopy-test
  LINK    tests/test-x86-cpuid-compat
  LINK    tests/numa-test
  LINK    tests/qmp-test
  LINK    tests/device-introspect-test
  LINK    tests/qom-test
  LINK    tests/test-hmp
  GTESTER tests/test-char
  GTESTER tests/check-qstring
  GTESTER tests/check-qnum
  GTESTER tests/check-qdict
  GTESTER tests/check-qnull
  GTESTER tests/check-qlist
  GTESTER tests/check-qjson
  LINK    tests/test-qobject-output-visitor
  LINK    tests/test-clone-visitor
  LINK    tests/test-qobject-input-visitor
  LINK    tests/test-qmp-commands
  LINK    tests/test-string-input-visitor
  LINK    tests/test-string-output-visitor
  LINK    tests/test-qmp-event
  LINK    tests/test-opts-visitor
  GTESTER tests/test-coroutine
  GTESTER tests/test-visitor-serialization
  GTESTER tests/test-iov
  GTESTER tests/test-aio
  GTESTER tests/test-aio-multithread
  GTESTER tests/test-hbitmap
  GTESTER tests/test-thread-pool
  GTESTER tests/test-blockjob
  GTESTER tests/test-throttle
  GTESTER tests/test-blockjob-txn
  GTESTER tests/test-x86-cpuid
  GTESTER tests/test-xbzrle
  GTESTER tests/test-vmstate
  GTESTER tests/test-cutils
Failed to load simple/primitive:b_1
Failed to load simple/primitive:i64_2
Failed to load simple/primitive:i32_1
Failed to load simple/primitive:i32_1
Failed to load test/with_tmp:a
Failed to load test/tmp_child_parent:f
Failed to load test/tmp_child:parent
Failed to load test/with_tmp:tmp
Failed to load test/tmp_child:diff
Failed to load test/with_tmp:tmp
Failed to load test/tmp_child:diff
Failed to load test/with_tmp:tmp
  GTESTER tests/test-shift128
  GTESTER tests/test-mul64
  GTESTER tests/rcutorture
  GTESTER tests/test-int128
  GTESTER tests/test-rcu-list
  GTESTER tests/test-qdist
  GTESTER tests/test-qht
  LINK    tests/test-qht-par
  GTESTER tests/test-bitops
  GTESTER tests/test-bitcnt
  GTESTER tests/check-qom-interface
  GTESTER tests/check-qom-proplist
  GTESTER tests/test-qemu-opts
  GTESTER tests/test-keyval
  GTESTER tests/test-write-threshold
  GTESTER tests/test-crypto-hash
  GTESTER tests/test-crypto-hmac
  GTESTER tests/test-crypto-cipher
  GTESTER tests/test-crypto-secret
  GTESTER tests/test-qga
  GTESTER tests/test-timed-average
  GTESTER tests/test-io-task
  GTESTER tests/test-io-channel-socket
  GTESTER tests/test-io-channel-file
  GTESTER tests/test-io-channel-command
  GTESTER tests/test-io-channel-buffer
  GTESTER tests/test-base64
  GTESTER tests/test-crypto-ivgen
  GTESTER tests/test-crypto-afsplit
  GTESTER tests/test-crypto-xts
  GTESTER tests/test-crypto-block
  GTESTER tests/test-logging
  GTESTER tests/test-replication
  GTESTER tests/test-bufferiszero
  GTESTER tests/test-uuid
  GTESTER tests/ptimer-test
  GTESTER tests/test-qapi-util
  GTESTER check-qtest-x86_64
  GTESTER check-qtest-aarch64
  GTESTER tests/test-qobject-output-visitor
  GTESTER tests/test-clone-visitor
  GTESTER tests/test-qobject-input-visitor
  GTESTER tests/test-qmp-commands
  GTESTER tests/test-string-input-visitor
  GTESTER tests/test-string-output-visitor
  GTESTER tests/test-qmp-event
  GTESTER tests/test-opts-visitor
  GTESTER tests/test-qht-par
**
ERROR:/tmp/qemu-test/src/tests/test-qga.c:78:fixture_setup: assertion failed (fixture->fd != -1): (-1 != -1)
GTester: last random seed: R02S61ee0a415e8c06db40ea88e324e74522
make: *** [check-tests/test-qga] Error 1
make: *** Waiting for unfinished jobs....
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Could not access KVM kernel module: No such file or directory
failed to initialize KVM: No such file or directory
Back to tcg accelerator.
Traceback (most recent call last):
  File "./tests/docker/docker.py", line 382, in <module>
    sys.exit(main())
  File "./tests/docker/docker.py", line 379, in main
    return args.cmdobj.run(args, argv)
  File "./tests/docker/docker.py", line 237, in run
    return Docker().run(argv, args.keep, quiet=args.quiet)
  File "./tests/docker/docker.py", line 205, in run
    quiet=quiet)
  File "./tests/docker/docker.py", line 123, in _do_check
    return subprocess.check_call(self._command + cmd, **kwargs)
  File "/usr/lib64/python2.7/subprocess.py", line 186, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['docker', 'run', '--label', 'com.qemu.instance.uuid=405c2b546d0111e7878c525400c803e1', '-u', '0', '-t', '--rm', '--net=none', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=8', '-e', 'DEBUG=', '-e', 'SHOW_ENV=1', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/var/tmp/patchew-tester-tmp-6slpqj5k/src/docker-src.2017-07-20-00.09.34.10036:/var/tmp/qemu:z,ro', '-v', '/root/.cache/qemu-docker-ccache:/var/tmp/ccache:z', 'qemu:centos6', '/var/tmp/qemu/run', 'test-quick']' returned non-zero exit status 2
tests/docker/Makefile.include:124: recipe for target 'docker-run' failed
make[1]: *** [docker-run] Error 1
make[1]: Leaving directory '/var/tmp/patchew-tester-tmp-6slpqj5k/src'
tests/docker/Makefile.include:156: recipe for target 'docker-run-test-quick@centos6' failed
make: *** [docker-run-test-quick@centos6] Error 2
=== OUTPUT END ===

Test command exited with code: 2


---
Email generated automatically by Patchew [http://patchew.org/].
Please send your feedback to patchew-devel@freelists.org
Dr. David Alan Gilbert July 21, 2017, 9:49 a.m. UTC | #2
* Jay Zhou (jianjay.zhou@huawei.com) wrote:
> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
> with a 8U24G vm(20G is really occupied), the main cost comes from
> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
> kvm_set_user_memory_region(). In kmod, the main cost is
> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
> zap the unsync sptes.

Hi Jay,
  Is this actually increasing the real downtime when the guest isn't
running, or is it just the reported time? I see that the s->downtime
value is calculated right after where we currently call
qemu_savevm_state_cleanup.

  I guess the biggest problem is that 300ms happens before we restart
the guest on the source if a migration fails.

> I think it can be optimized:
> (1) source vm will be destroyed if the migration is successfully done,
>     so the resources will be cleanuped automatically by the system
> (2) delay the cleanup if the migration failed

I don't like putting it in qmp_cont; that shouldn't have migration magic
in it.
I guess we could put it in migrate_fd_cleanup perhaps? It gets called on
a bh near the end -  or could we just move it closer to the end of 
migration_thread?

However, we would need to be a bit careful of anything that needs
cleaning up before the source restarts on failure; I'm not sure of
the semantics of all the current things wired into save_cleanup.

Dave


> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
> ---
>  migration/migration.c | 16 +++++++++-------
>  qmp.c                 | 10 ++++++++++
>  2 files changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index a0db40d..72832be 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
>          if (qemu_file_get_error(s->to_dst_file)) {
>              migrate_set_state(&s->state, current_active_state,
>                                MIGRATION_STATUS_FAILED);
> +            /*
> +             * The resource has been allocated by migration will be reused in
> +             * COLO process, so don't release them.
> +             */
> +            if (!enable_colo) {
> +                qemu_mutex_lock_iothread();
> +                qemu_savevm_state_cleanup();
> +                qemu_mutex_unlock_iothread();
> +            }
>              trace_migration_thread_file_err();
>              break;
>          }
> @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
>      end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
>  
>      qemu_mutex_lock_iothread();
> -    /*
> -     * The resource has been allocated by migration will be reused in COLO
> -     * process, so don't release them.
> -     */
> -    if (!enable_colo) {
> -        qemu_savevm_state_cleanup();
> -    }
>      if (s->state == MIGRATION_STATUS_COMPLETED) {
>          uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
>          s->total_time = end_time - s->total_time;
> diff --git a/qmp.c b/qmp.c
> index b86201e..0e68eaa 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -37,6 +37,8 @@
>  #include "qom/object_interfaces.h"
>  #include "hw/mem/pc-dimm.h"
>  #include "hw/acpi/acpi_dev_interface.h"
> +#include "migration/migration.h"
> +#include "migration/savevm.h"
>  
>  NameInfo *qmp_query_name(Error **errp)
>  {
> @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
>      if (runstate_check(RUN_STATE_INMIGRATE)) {
>          autostart = 1;
>      } else {
> +        /*
> +         * Delay the cleanup to reduce the downtime of migration.
> +         * The resource has been allocated by migration will be reused
> +         * in COLO process, so don't release them.
> +         */
> +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
> +            qemu_savevm_state_cleanup();
> +        }
>          vm_start();
>      }
>  }
> -- 
> 1.8.3.1
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Zhoujian (jay) July 21, 2017, 12:23 p.m. UTC | #3
Hi Dave,

On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
>> with a 8U24G vm(20G is really occupied), the main cost comes from
>> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
>> kvm_set_user_memory_region(). In kmod, the main cost is
>> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
>> zap the unsync sptes.
>
> Hi Jay,
>    Is this actually increasing the real downtime when the guest isn't
> running, or is it just the reported time? I see that the s->downtime
> value is calculated right after where we currently call
> qemu_savevm_state_cleanup.

It actually increased the real downtime, I used the "ping" command to
test. Reason is that the source side libvirt sends qmp to qemu to query
the status of migration, which needs the BQL. qemu_savevm_state_cleanup
is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
has not finished. And the source side libvirt delays about 300ms to notify
the destination side libvirt to send the "cont" command to start the vm.

I think the value of s->downtime is not accurate enough, maybe we could
move the calculation of end_time after qemu_savevm_state_cleanup has done.

>    I guess the biggest problem is that 300ms happens before we restart
> the guest on the source if a migration fails.

300ms happens even if a migration succeeds.

>> I think it can be optimized:
>> (1) source vm will be destroyed if the migration is successfully done,
>>      so the resources will be cleanuped automatically by the system
>> (2) delay the cleanup if the migration failed
>
> I don't like putting it in qmp_cont; that shouldn't have migration magic
> in it.

Yes, it is not a ideal place. :(

> I guess we could put it in migrate_fd_cleanup perhaps? It gets called on
> a bh near the end -  or could we just move it closer to the end of
> migration_thread?

I have tested putting it in migrate_fd_cleanup, but the downtime is not
optimized. So I think it is the same to move it closer to the end of
migration_thread if it holds the BQL.
Could we put it in migrate_init?

Thanks,
Jay

> However, we would need to be a bit careful of anything that needs
> cleaning up before the source restarts on failure; I'm not sure of
> the semantics of all the current things wired into save_cleanup.
>
> Dave
>
>
>> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
>> ---
>>   migration/migration.c | 16 +++++++++-------
>>   qmp.c                 | 10 ++++++++++
>>   2 files changed, 19 insertions(+), 7 deletions(-)
>>
>> diff --git a/migration/migration.c b/migration/migration.c
>> index a0db40d..72832be 100644
>> --- a/migration/migration.c
>> +++ b/migration/migration.c
>> @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
>>           if (qemu_file_get_error(s->to_dst_file)) {
>>               migrate_set_state(&s->state, current_active_state,
>>                                 MIGRATION_STATUS_FAILED);
>> +            /*
>> +             * The resource has been allocated by migration will be reused in
>> +             * COLO process, so don't release them.
>> +             */
>> +            if (!enable_colo) {
>> +                qemu_mutex_lock_iothread();
>> +                qemu_savevm_state_cleanup();
>> +                qemu_mutex_unlock_iothread();
>> +            }
>>               trace_migration_thread_file_err();
>>               break;
>>           }
>> @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
>>       end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
>>
>>       qemu_mutex_lock_iothread();
>> -    /*
>> -     * The resource has been allocated by migration will be reused in COLO
>> -     * process, so don't release them.
>> -     */
>> -    if (!enable_colo) {
>> -        qemu_savevm_state_cleanup();
>> -    }
>>       if (s->state == MIGRATION_STATUS_COMPLETED) {
>>           uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
>>           s->total_time = end_time - s->total_time;
>> diff --git a/qmp.c b/qmp.c
>> index b86201e..0e68eaa 100644
>> --- a/qmp.c
>> +++ b/qmp.c
>> @@ -37,6 +37,8 @@
>>   #include "qom/object_interfaces.h"
>>   #include "hw/mem/pc-dimm.h"
>>   #include "hw/acpi/acpi_dev_interface.h"
>> +#include "migration/migration.h"
>> +#include "migration/savevm.h"
>>
>>   NameInfo *qmp_query_name(Error **errp)
>>   {
>> @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
>>       if (runstate_check(RUN_STATE_INMIGRATE)) {
>>           autostart = 1;
>>       } else {
>> +        /*
>> +         * Delay the cleanup to reduce the downtime of migration.
>> +         * The resource has been allocated by migration will be reused
>> +         * in COLO process, so don't release them.
>> +         */
>> +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
>> +            qemu_savevm_state_cleanup();
>> +        }
>>           vm_start();
>>       }
>>   }
>> --
>> 1.8.3.1
>>
>>
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>
> .
>
Dr. David Alan Gilbert July 24, 2017, 3:35 p.m. UTC | #4
* Jay Zhou (jianjay.zhou@huawei.com) wrote:
> Hi Dave,
> 
> On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
> > * Jay Zhou (jianjay.zhou@huawei.com) wrote:
> > > Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
> > > with a 8U24G vm(20G is really occupied), the main cost comes from
> > > KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
> > > kvm_set_user_memory_region(). In kmod, the main cost is
> > > kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
> > > zap the unsync sptes.
> > 
> > Hi Jay,
> >    Is this actually increasing the real downtime when the guest isn't
> > running, or is it just the reported time? I see that the s->downtime
> > value is calculated right after where we currently call
> > qemu_savevm_state_cleanup.
> 
> It actually increased the real downtime, I used the "ping" command to
> test. Reason is that the source side libvirt sends qmp to qemu to query
> the status of migration, which needs the BQL. qemu_savevm_state_cleanup
> is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
> has not finished. And the source side libvirt delays about 300ms to notify
> the destination side libvirt to send the "cont" command to start the vm.
> 
> I think the value of s->downtime is not accurate enough, maybe we could
> move the calculation of end_time after qemu_savevm_state_cleanup has done.

I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
on only a small VM.

> >    I guess the biggest problem is that 300ms happens before we restart
> > the guest on the source if a migration fails.
> 
> 300ms happens even if a migration succeeds.

Hmm, OK, this needs fixing then - it does explain a result I saw a while
ago where the downtime was much bigger with libvirt than it was with
qemu on it's own.

> > > I think it can be optimized:
> > > (1) source vm will be destroyed if the migration is successfully done,
> > >      so the resources will be cleanuped automatically by the system
> > > (2) delay the cleanup if the migration failed
> > 
> > I don't like putting it in qmp_cont; that shouldn't have migration magic
> > in it.
> 
> Yes, it is not a ideal place. :(
> 
> > I guess we could put it in migrate_fd_cleanup perhaps? It gets called on
> > a bh near the end -  or could we just move it closer to the end of
> > migration_thread?
> 
> I have tested putting it in migrate_fd_cleanup, but the downtime is not
> optimized. So I think it is the same to move it closer to the end of
> migration_thread if it holds the BQL.
> Could we put it in migrate_init?

Your explanation above hints as to why migrate_fd_cleanup doesn't help;
it's because we're still going to be doing it with the BQL taken.

Can you tell me which version of libvirt you're using?
I thought the newer ones were supposed to use events so they did't
have to poll qemu.

 If we move qemu_savevm_state_cleanup is it still safe? Are there
some things we're supposed to do at that point which are wrong if
we don't.

I wonder about something like;  take a mutex in
memory_global_dirty_log_start, release it in
memory_global_dirty_log_stop.  Then make ram_save_cleanup start
a new thread that does the call to memory_global_dirty_log_stop.

Dave

> Thanks,
> Jay
> 
> > However, we would need to be a bit careful of anything that needs
> > cleaning up before the source restarts on failure; I'm not sure of
> > the semantics of all the current things wired into save_cleanup.
> > 
> > Dave
> > 
> > 
> > > Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
> > > ---
> > >   migration/migration.c | 16 +++++++++-------
> > >   qmp.c                 | 10 ++++++++++
> > >   2 files changed, 19 insertions(+), 7 deletions(-)
> > > 
> > > diff --git a/migration/migration.c b/migration/migration.c
> > > index a0db40d..72832be 100644
> > > --- a/migration/migration.c
> > > +++ b/migration/migration.c
> > > @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
> > >           if (qemu_file_get_error(s->to_dst_file)) {
> > >               migrate_set_state(&s->state, current_active_state,
> > >                                 MIGRATION_STATUS_FAILED);
> > > +            /*
> > > +             * The resource has been allocated by migration will be reused in
> > > +             * COLO process, so don't release them.
> > > +             */
> > > +            if (!enable_colo) {
> > > +                qemu_mutex_lock_iothread();
> > > +                qemu_savevm_state_cleanup();
> > > +                qemu_mutex_unlock_iothread();
> > > +            }
> > >               trace_migration_thread_file_err();
> > >               break;
> > >           }
> > > @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
> > >       end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
> > > 
> > >       qemu_mutex_lock_iothread();
> > > -    /*
> > > -     * The resource has been allocated by migration will be reused in COLO
> > > -     * process, so don't release them.
> > > -     */
> > > -    if (!enable_colo) {
> > > -        qemu_savevm_state_cleanup();
> > > -    }
> > >       if (s->state == MIGRATION_STATUS_COMPLETED) {
> > >           uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
> > >           s->total_time = end_time - s->total_time;
> > > diff --git a/qmp.c b/qmp.c
> > > index b86201e..0e68eaa 100644
> > > --- a/qmp.c
> > > +++ b/qmp.c
> > > @@ -37,6 +37,8 @@
> > >   #include "qom/object_interfaces.h"
> > >   #include "hw/mem/pc-dimm.h"
> > >   #include "hw/acpi/acpi_dev_interface.h"
> > > +#include "migration/migration.h"
> > > +#include "migration/savevm.h"
> > > 
> > >   NameInfo *qmp_query_name(Error **errp)
> > >   {
> > > @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
> > >       if (runstate_check(RUN_STATE_INMIGRATE)) {
> > >           autostart = 1;
> > >       } else {
> > > +        /*
> > > +         * Delay the cleanup to reduce the downtime of migration.
> > > +         * The resource has been allocated by migration will be reused
> > > +         * in COLO process, so don't release them.
> > > +         */
> > > +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
> > > +            qemu_savevm_state_cleanup();
> > > +        }
> > >           vm_start();
> > >       }
> > >   }
> > > --
> > > 1.8.3.1
> > > 
> > > 
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> > 
> > .
> > 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Paolo Bonzini July 24, 2017, 4:33 p.m. UTC | #5
On 24/07/2017 17:35, Dr. David Alan Gilbert wrote:
> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>> Hi Dave,
>>
>> On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
>>> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>>>> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
>>>> with a 8U24G vm(20G is really occupied), the main cost comes from
>>>> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
>>>> kvm_set_user_memory_region(). In kmod, the main cost is
>>>> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
>>>> zap the unsync sptes.
>>>
>>> Hi Jay,
>>>    Is this actually increasing the real downtime when the guest isn't
>>> running, or is it just the reported time? I see that the s->downtime
>>> value is calculated right after where we currently call
>>> qemu_savevm_state_cleanup.
>>
>> It actually increased the real downtime, I used the "ping" command to
>> test. Reason is that the source side libvirt sends qmp to qemu to query
>> the status of migration, which needs the BQL. qemu_savevm_state_cleanup
>> is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
>> has not finished. And the source side libvirt delays about 300ms to notify
>> the destination side libvirt to send the "cont" command to start the vm.
>>
>> I think the value of s->downtime is not accurate enough, maybe we could
>> move the calculation of end_time after qemu_savevm_state_cleanup has done.
> 
> I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
> teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
> on only a small VM.

Xiao Guangrong is working on something vaguely related (but different
and simpler because it's entirely contained within KVM), which is to
make log_sync faster.

The Intel folks working on clear containers also would like
MemoryListeners to have a better complexity, but that's again separate
from the "zapping" of SPTEs.

> Can you tell me which version of libvirt you're using?
> I thought the newer ones were supposed to use events so they did't
> have to poll qemu.
> 
>  If we move qemu_savevm_state_cleanup is it still safe? Are there
> some things we're supposed to do at that point which are wrong if
> we don't.
> 
> I wonder about something like;  take a mutex in
> memory_global_dirty_log_start, release it in
> memory_global_dirty_log_stop.  Then make ram_save_cleanup start
> a new thread that does the call to memory_global_dirty_log_stop.

I don't like having such a long-lived mutex (it seems like a recipe for
deadlocks with the BQL), plus memory_region_transaction_commit (the
expensive part of memory_global_dirty_log_stop) needs to be under the
BQL itself because it calls MemoryListeners.

Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
if it's called while runstate_running() returns false (which should be
always the case)?

It could even be entirely enclosed within memory.c if you do it with a
VMChangeStateHandler.

Thanks,

Paolo

> Dave
> 
>> Thanks,
>> Jay
>>
>>> However, we would need to be a bit careful of anything that needs
>>> cleaning up before the source restarts on failure; I'm not sure of
>>> the semantics of all the current things wired into save_cleanup.
>>>
>>> Dave
>>>
>>>
>>>> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
>>>> ---
>>>>   migration/migration.c | 16 +++++++++-------
>>>>   qmp.c                 | 10 ++++++++++
>>>>   2 files changed, 19 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/migration/migration.c b/migration/migration.c
>>>> index a0db40d..72832be 100644
>>>> --- a/migration/migration.c
>>>> +++ b/migration/migration.c
>>>> @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
>>>>           if (qemu_file_get_error(s->to_dst_file)) {
>>>>               migrate_set_state(&s->state, current_active_state,
>>>>                                 MIGRATION_STATUS_FAILED);
>>>> +            /*
>>>> +             * The resource has been allocated by migration will be reused in
>>>> +             * COLO process, so don't release them.
>>>> +             */
>>>> +            if (!enable_colo) {
>>>> +                qemu_mutex_lock_iothread();
>>>> +                qemu_savevm_state_cleanup();
>>>> +                qemu_mutex_unlock_iothread();
>>>> +            }
>>>>               trace_migration_thread_file_err();
>>>>               break;
>>>>           }
>>>> @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
>>>>       end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
>>>>
>>>>       qemu_mutex_lock_iothread();
>>>> -    /*
>>>> -     * The resource has been allocated by migration will be reused in COLO
>>>> -     * process, so don't release them.
>>>> -     */
>>>> -    if (!enable_colo) {
>>>> -        qemu_savevm_state_cleanup();
>>>> -    }
>>>>       if (s->state == MIGRATION_STATUS_COMPLETED) {
>>>>           uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
>>>>           s->total_time = end_time - s->total_time;
>>>> diff --git a/qmp.c b/qmp.c
>>>> index b86201e..0e68eaa 100644
>>>> --- a/qmp.c
>>>> +++ b/qmp.c
>>>> @@ -37,6 +37,8 @@
>>>>   #include "qom/object_interfaces.h"
>>>>   #include "hw/mem/pc-dimm.h"
>>>>   #include "hw/acpi/acpi_dev_interface.h"
>>>> +#include "migration/migration.h"
>>>> +#include "migration/savevm.h"
>>>>
>>>>   NameInfo *qmp_query_name(Error **errp)
>>>>   {
>>>> @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
>>>>       if (runstate_check(RUN_STATE_INMIGRATE)) {
>>>>           autostart = 1;
>>>>       } else {
>>>> +        /*
>>>> +         * Delay the cleanup to reduce the downtime of migration.
>>>> +         * The resource has been allocated by migration will be reused
>>>> +         * in COLO process, so don't release them.
>>>> +         */
>>>> +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
>>>> +            qemu_savevm_state_cleanup();
>>>> +        }
>>>>           vm_start();
>>>>       }
>>>>   }
>>>> --
>>>> 1.8.3.1
>>>>
>>>>
>>> --
>>> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>>>
>>> .
>>>
>>
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>
Dr. David Alan Gilbert July 24, 2017, 7:03 p.m. UTC | #6
* Paolo Bonzini (pbonzini@redhat.com) wrote:
> On 24/07/2017 17:35, Dr. David Alan Gilbert wrote:
> > * Jay Zhou (jianjay.zhou@huawei.com) wrote:
> >> Hi Dave,
> >>
> >> On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
> >>> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
> >>>> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
> >>>> with a 8U24G vm(20G is really occupied), the main cost comes from
> >>>> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
> >>>> kvm_set_user_memory_region(). In kmod, the main cost is
> >>>> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
> >>>> zap the unsync sptes.
> >>>
> >>> Hi Jay,
> >>>    Is this actually increasing the real downtime when the guest isn't
> >>> running, or is it just the reported time? I see that the s->downtime
> >>> value is calculated right after where we currently call
> >>> qemu_savevm_state_cleanup.
> >>
> >> It actually increased the real downtime, I used the "ping" command to
> >> test. Reason is that the source side libvirt sends qmp to qemu to query
> >> the status of migration, which needs the BQL. qemu_savevm_state_cleanup
> >> is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
> >> has not finished. And the source side libvirt delays about 300ms to notify
> >> the destination side libvirt to send the "cont" command to start the vm.
> >>
> >> I think the value of s->downtime is not accurate enough, maybe we could
> >> move the calculation of end_time after qemu_savevm_state_cleanup has done.
> > 
> > I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
> > teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
> > on only a small VM.
> 
> Xiao Guangrong is working on something vaguely related (but different
> and simpler because it's entirely contained within KVM), which is to
> make log_sync faster.
> 
> The Intel folks working on clear containers also would like
> MemoryListeners to have a better complexity, but that's again separate
> from the "zapping" of SPTEs.

They do keep popping up; I remember they're a pain in COLO.

> > Can you tell me which version of libvirt you're using?
> > I thought the newer ones were supposed to use events so they did't
> > have to poll qemu.
> > 
> >  If we move qemu_savevm_state_cleanup is it still safe? Are there
> > some things we're supposed to do at that point which are wrong if
> > we don't.
> > 
> > I wonder about something like;  take a mutex in
> > memory_global_dirty_log_start, release it in
> > memory_global_dirty_log_stop.  Then make ram_save_cleanup start
> > a new thread that does the call to memory_global_dirty_log_stop.
> 
> I don't like having such a long-lived mutex (it seems like a recipe for
> deadlocks with the BQL), plus memory_region_transaction_commit (the
> expensive part of memory_global_dirty_log_stop) needs to be under the
> BQL itself because it calls MemoryListeners.
> 
> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
> if it's called while runstate_running() returns false (which should be
> always the case)?
> 
> It could even be entirely enclosed within memory.c if you do it with a
> VMChangeStateHandler.

This still causes the BQL to be held for quite a while; albeit at a less
critical point.

In this and the existing case we don't actually need efficiency - what we need is just
not to be holding onto the BQL for so long;  could we do a less
efficient commit here, removing one region at a time, yielding the lock
and retaking it?


> Thanks,
> 
> Paolo
> 
> > Dave
> > 
> >> Thanks,
> >> Jay
> >>
> >>> However, we would need to be a bit careful of anything that needs
> >>> cleaning up before the source restarts on failure; I'm not sure of
> >>> the semantics of all the current things wired into save_cleanup.
> >>>
> >>> Dave
> >>>
> >>>
> >>>> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
> >>>> ---
> >>>>   migration/migration.c | 16 +++++++++-------
> >>>>   qmp.c                 | 10 ++++++++++
> >>>>   2 files changed, 19 insertions(+), 7 deletions(-)
> >>>>
> >>>> diff --git a/migration/migration.c b/migration/migration.c
> >>>> index a0db40d..72832be 100644
> >>>> --- a/migration/migration.c
> >>>> +++ b/migration/migration.c
> >>>> @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
> >>>>           if (qemu_file_get_error(s->to_dst_file)) {
> >>>>               migrate_set_state(&s->state, current_active_state,
> >>>>                                 MIGRATION_STATUS_FAILED);
> >>>> +            /*
> >>>> +             * The resource has been allocated by migration will be reused in
> >>>> +             * COLO process, so don't release them.
> >>>> +             */
> >>>> +            if (!enable_colo) {
> >>>> +                qemu_mutex_lock_iothread();
> >>>> +                qemu_savevm_state_cleanup();
> >>>> +                qemu_mutex_unlock_iothread();
> >>>> +            }
> >>>>               trace_migration_thread_file_err();
> >>>>               break;
> >>>>           }
> >>>> @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
> >>>>       end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
> >>>>
> >>>>       qemu_mutex_lock_iothread();
> >>>> -    /*
> >>>> -     * The resource has been allocated by migration will be reused in COLO
> >>>> -     * process, so don't release them.
> >>>> -     */
> >>>> -    if (!enable_colo) {
> >>>> -        qemu_savevm_state_cleanup();
> >>>> -    }
> >>>>       if (s->state == MIGRATION_STATUS_COMPLETED) {
> >>>>           uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
> >>>>           s->total_time = end_time - s->total_time;
> >>>> diff --git a/qmp.c b/qmp.c
> >>>> index b86201e..0e68eaa 100644
> >>>> --- a/qmp.c
> >>>> +++ b/qmp.c
> >>>> @@ -37,6 +37,8 @@
> >>>>   #include "qom/object_interfaces.h"
> >>>>   #include "hw/mem/pc-dimm.h"
> >>>>   #include "hw/acpi/acpi_dev_interface.h"
> >>>> +#include "migration/migration.h"
> >>>> +#include "migration/savevm.h"
> >>>>
> >>>>   NameInfo *qmp_query_name(Error **errp)
> >>>>   {
> >>>> @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
> >>>>       if (runstate_check(RUN_STATE_INMIGRATE)) {
> >>>>           autostart = 1;
> >>>>       } else {
> >>>> +        /*
> >>>> +         * Delay the cleanup to reduce the downtime of migration.
> >>>> +         * The resource has been allocated by migration will be reused
> >>>> +         * in COLO process, so don't release them.
> >>>> +         */
> >>>> +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
> >>>> +            qemu_savevm_state_cleanup();
> >>>> +        }
> >>>>           vm_start();
> >>>>       }
> >>>>   }
> >>>> --
> >>>> 1.8.3.1
> >>>>
> >>>>
> >>> --
> >>> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> >>>
> >>> .
> >>>
> >>
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> > 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Paolo Bonzini July 24, 2017, 8:38 p.m. UTC | #7
On 24/07/2017 21:03, Dr. David Alan Gilbert wrote:
>> I don't like having such a long-lived mutex (it seems like a recipe for
>> deadlocks with the BQL), plus memory_region_transaction_commit (the
>> expensive part of memory_global_dirty_log_stop) needs to be under the
>> BQL itself because it calls MemoryListeners.
>>
>> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
>> if it's called while runstate_running() returns false (which should be
>> always the case)?
>>
>> It could even be entirely enclosed within memory.c if you do it with a
>> VMChangeStateHandler.
> This still causes the BQL to be held for quite a while; albeit at a less
> critical point.
> 
> In this and the existing case we don't actually need efficiency - what we need is just
> not to be holding onto the BQL for so long;  could we do a less
> efficient commit here, removing one region at a time, yielding the lock
> and retaking it?

I'm worried that if you release the lock and retake it you open a window
where someone else could start a commit, and
memory_global_dirty_log_stop's commit would use outdated information.

The problem is that a coarse lock, such as the BQL, is very hard to
break into another lock with long critical sections (a "memory map
commit lock" in this case).  It's obviously very easy to say "the new
lock nests inside the BQL"... but then, because you created the lock to
move things out of the BQL, any callback inside the new lock cannot take
the memory map commit lock, and you need to make entire subsystems
thread-safe.  If the new lock nests outside the BQL instead, it's
simpler to avoid deadlocks, but you need to be careful about releasing
the BQL and any reentrancy implications of doing that.

One strategy that worked well so far has been to use two locks, one of
them being the BQL, where you can take either lock for reads and both
for writes.

Paolo
Zhoujian (jay) July 25, 2017, 7:09 a.m. UTC | #8
On 2017/7/24 23:35, Dr. David Alan Gilbert wrote:
> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>> Hi Dave,
>>
>> On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
>>> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>>>> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
>>>> with a 8U24G vm(20G is really occupied), the main cost comes from
>>>> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
>>>> kvm_set_user_memory_region(). In kmod, the main cost is
>>>> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
>>>> zap the unsync sptes.
>>>
>>> Hi Jay,
>>>     Is this actually increasing the real downtime when the guest isn't
>>> running, or is it just the reported time? I see that the s->downtime
>>> value is calculated right after where we currently call
>>> qemu_savevm_state_cleanup.
>>
>> It actually increased the real downtime, I used the "ping" command to
>> test. Reason is that the source side libvirt sends qmp to qemu to query
>> the status of migration, which needs the BQL. qemu_savevm_state_cleanup
>> is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
>> has not finished. And the source side libvirt delays about 300ms to notify
>> the destination side libvirt to send the "cont" command to start the vm.
>>
>> I think the value of s->downtime is not accurate enough, maybe we could
>> move the calculation of end_time after qemu_savevm_state_cleanup has done.
>
> I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
> teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
> on only a small VM.
>
>>>     I guess the biggest problem is that 300ms happens before we restart
>>> the guest on the source if a migration fails.
>>
>> 300ms happens even if a migration succeeds.
>
> Hmm, OK, this needs fixing then - it does explain a result I saw a while
> ago where the downtime was much bigger with libvirt than it was with
> qemu on it's own.
>
>>>> I think it can be optimized:
>>>> (1) source vm will be destroyed if the migration is successfully done,
>>>>       so the resources will be cleanuped automatically by the system
>>>> (2) delay the cleanup if the migration failed
>>>
>>> I don't like putting it in qmp_cont; that shouldn't have migration magic
>>> in it.
>>
>> Yes, it is not a ideal place. :(
>>
>>> I guess we could put it in migrate_fd_cleanup perhaps? It gets called on
>>> a bh near the end -  or could we just move it closer to the end of
>>> migration_thread?
>>
>> I have tested putting it in migrate_fd_cleanup, but the downtime is not
>> optimized. So I think it is the same to move it closer to the end of
>> migration_thread if it holds the BQL.
>> Could we put it in migrate_init?
>
> Your explanation above hints as to why migrate_fd_cleanup doesn't help;
> it's because we're still going to be doing it with the BQL taken.

Yes, it is.

> Can you tell me which version of libvirt you're using?

I'm using 1.3.4

> I thought the newer ones were supposed to use events so they did't
> have to poll qemu.

After checking the codes of the newest libvirt, I think it is the same
in the qemuMigrationWaitForCompletion function, which is used to poll
qemu every 50ms.

Thanks,
Jay

>   If we move qemu_savevm_state_cleanup is it still safe? Are there
> some things we're supposed to do at that point which are wrong if
> we don't.
>
> I wonder about something like;  take a mutex in
> memory_global_dirty_log_start, release it in
> memory_global_dirty_log_stop.  Then make ram_save_cleanup start
> a new thread that does the call to memory_global_dirty_log_stop.
>
> Dave
>
Zhoujian (jay) July 25, 2017, 7:29 a.m. UTC | #9
On 2017/7/25 0:33, Paolo Bonzini wrote:
> On 24/07/2017 17:35, Dr. David Alan Gilbert wrote:
>> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>>> Hi Dave,
>>>
>>> On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
>>>> * Jay Zhou (jianjay.zhou@huawei.com) wrote:
>>>>> Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
>>>>> with a 8U24G vm(20G is really occupied), the main cost comes from
>>>>> KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
>>>>> kvm_set_user_memory_region(). In kmod, the main cost is
>>>>> kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
>>>>> zap the unsync sptes.
>>>>
>>>> Hi Jay,
>>>>     Is this actually increasing the real downtime when the guest isn't
>>>> running, or is it just the reported time? I see that the s->downtime
>>>> value is calculated right after where we currently call
>>>> qemu_savevm_state_cleanup.
>>>
>>> It actually increased the real downtime, I used the "ping" command to
>>> test. Reason is that the source side libvirt sends qmp to qemu to query
>>> the status of migration, which needs the BQL. qemu_savevm_state_cleanup
>>> is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
>>> has not finished. And the source side libvirt delays about 300ms to notify
>>> the destination side libvirt to send the "cont" command to start the vm.
>>>
>>> I think the value of s->downtime is not accurate enough, maybe we could
>>> move the calculation of end_time after qemu_savevm_state_cleanup has done.
>>
>> I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
>> teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
>> on only a small VM.
>
> Xiao Guangrong is working on something vaguely related (but different
> and simpler because it's entirely contained within KVM), which is to
> make log_sync faster.
>
> The Intel folks working on clear containers also would like
> MemoryListeners to have a better complexity, but that's again separate
> from the "zapping" of SPTEs.
>
>> Can you tell me which version of libvirt you're using?
>> I thought the newer ones were supposed to use events so they did't
>> have to poll qemu.
>>
>>   If we move qemu_savevm_state_cleanup is it still safe? Are there
>> some things we're supposed to do at that point which are wrong if
>> we don't.
>>
>> I wonder about something like;  take a mutex in
>> memory_global_dirty_log_start, release it in
>> memory_global_dirty_log_stop.  Then make ram_save_cleanup start
>> a new thread that does the call to memory_global_dirty_log_stop.
>
> I don't like having such a long-lived mutex (it seems like a recipe for
> deadlocks with the BQL), plus memory_region_transaction_commit (the
> expensive part of memory_global_dirty_log_stop) needs to be under the
> BQL itself because it calls MemoryListeners.
>
> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
> if it's called while runstate_running() returns false (which should be
> always the case)?

It is logical, but then we need to put some migration related codes into
the file of cpus.c(in my patch, I put some codes into the file of qmp.c),
is there any elegant way to reduce the coupling?

Thanks,
Jay

> It could even be entirely enclosed within memory.c if you do it with a
> VMChangeStateHandler.
>
> Thanks,
>
> Paolo
>
>> Dave
>>
>>> Thanks,
>>> Jay
>>>
>>>> However, we would need to be a bit careful of anything that needs
>>>> cleaning up before the source restarts on failure; I'm not sure of
>>>> the semantics of all the current things wired into save_cleanup.
>>>>
>>>> Dave
>>>>
>>>>
>>>>> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
>>>>> ---
>>>>>    migration/migration.c | 16 +++++++++-------
>>>>>    qmp.c                 | 10 ++++++++++
>>>>>    2 files changed, 19 insertions(+), 7 deletions(-)
>>>>>
>>>>> diff --git a/migration/migration.c b/migration/migration.c
>>>>> index a0db40d..72832be 100644
>>>>> --- a/migration/migration.c
>>>>> +++ b/migration/migration.c
>>>>> @@ -1877,6 +1877,15 @@ static void *migration_thread(void *opaque)
>>>>>            if (qemu_file_get_error(s->to_dst_file)) {
>>>>>                migrate_set_state(&s->state, current_active_state,
>>>>>                                  MIGRATION_STATUS_FAILED);
>>>>> +            /*
>>>>> +             * The resource has been allocated by migration will be reused in
>>>>> +             * COLO process, so don't release them.
>>>>> +             */
>>>>> +            if (!enable_colo) {
>>>>> +                qemu_mutex_lock_iothread();
>>>>> +                qemu_savevm_state_cleanup();
>>>>> +                qemu_mutex_unlock_iothread();
>>>>> +            }
>>>>>                trace_migration_thread_file_err();
>>>>>                break;
>>>>>            }
>>>>> @@ -1916,13 +1925,6 @@ static void *migration_thread(void *opaque)
>>>>>        end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
>>>>>
>>>>>        qemu_mutex_lock_iothread();
>>>>> -    /*
>>>>> -     * The resource has been allocated by migration will be reused in COLO
>>>>> -     * process, so don't release them.
>>>>> -     */
>>>>> -    if (!enable_colo) {
>>>>> -        qemu_savevm_state_cleanup();
>>>>> -    }
>>>>>        if (s->state == MIGRATION_STATUS_COMPLETED) {
>>>>>            uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
>>>>>            s->total_time = end_time - s->total_time;
>>>>> diff --git a/qmp.c b/qmp.c
>>>>> index b86201e..0e68eaa 100644
>>>>> --- a/qmp.c
>>>>> +++ b/qmp.c
>>>>> @@ -37,6 +37,8 @@
>>>>>    #include "qom/object_interfaces.h"
>>>>>    #include "hw/mem/pc-dimm.h"
>>>>>    #include "hw/acpi/acpi_dev_interface.h"
>>>>> +#include "migration/migration.h"
>>>>> +#include "migration/savevm.h"
>>>>>
>>>>>    NameInfo *qmp_query_name(Error **errp)
>>>>>    {
>>>>> @@ -200,6 +202,14 @@ void qmp_cont(Error **errp)
>>>>>        if (runstate_check(RUN_STATE_INMIGRATE)) {
>>>>>            autostart = 1;
>>>>>        } else {
>>>>> +        /*
>>>>> +         * Delay the cleanup to reduce the downtime of migration.
>>>>> +         * The resource has been allocated by migration will be reused
>>>>> +         * in COLO process, so don't release them.
>>>>> +         */
>>>>> +        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
>>>>> +            qemu_savevm_state_cleanup();
>>>>> +        }
>>>>>            vm_start();
>>>>>        }
>>>>>    }
>>>>> --
>>>>> 1.8.3.1
>>>>>
>>>>>
>>>> --
>>>> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>>>>
>>>> .
>>>>
>>>
>> --
>> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>>
>
>
> .
>
Paolo Bonzini July 25, 2017, 8:18 a.m. UTC | #10
On 25/07/2017 09:29, Jay Zhou wrote:
>>
>>
>> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
>> if it's called while runstate_running() returns false (which should be
>> always the case)?
> 
> It is logical, but then we need to put some migration related codes into
> the file of cpus.c(in my patch, I put some codes into the file of qmp.c),
> is there any elegant way to reduce the coupling?

See below:

>> It could even be entirely enclosed within memory.c if you do it with a
>> VMChangeStateHandler. 

If memory_global_dirty_log_stop runs with !runstate_running(), instead
of doing the memory transaction you set a VMChangeStateHandler and
return immediately.

The VMChangeStateHandler then does the actual work just before the VM
starts running.

memory_global_dirty_log_start also needs to delete the
VMChangeStateHandler if it is present.

Paolo
Dr. David Alan Gilbert July 25, 2017, 10:34 a.m. UTC | #11
* Jay Zhou (jianjay.zhou@huawei.com) wrote:
> 
> On 2017/7/24 23:35, Dr. David Alan Gilbert wrote:
> > * Jay Zhou (jianjay.zhou@huawei.com) wrote:
> > > Hi Dave,
> > > 
> > > On 2017/7/21 17:49, Dr. David Alan Gilbert wrote:
> > > > * Jay Zhou (jianjay.zhou@huawei.com) wrote:
> > > > > Qemu_savevm_state_cleanup() takes about 300ms in my ram migration tests
> > > > > with a 8U24G vm(20G is really occupied), the main cost comes from
> > > > > KVM_SET_USER_MEMORY_REGION ioctl when mem.memory_size = 0 in
> > > > > kvm_set_user_memory_region(). In kmod, the main cost is
> > > > > kvm_zap_obsolete_pages(), which traverses the active_mmu_pages list to
> > > > > zap the unsync sptes.
> > > > 
> > > > Hi Jay,
> > > >     Is this actually increasing the real downtime when the guest isn't
> > > > running, or is it just the reported time? I see that the s->downtime
> > > > value is calculated right after where we currently call
> > > > qemu_savevm_state_cleanup.
> > > 
> > > It actually increased the real downtime, I used the "ping" command to
> > > test. Reason is that the source side libvirt sends qmp to qemu to query
> > > the status of migration, which needs the BQL. qemu_savevm_state_cleanup
> > > is done with BQL, qemu can not handle the qmp if qemu_savevm_state_cleanup
> > > has not finished. And the source side libvirt delays about 300ms to notify
> > > the destination side libvirt to send the "cont" command to start the vm.
> > > 
> > > I think the value of s->downtime is not accurate enough, maybe we could
> > > move the calculation of end_time after qemu_savevm_state_cleanup has done.
> > 
> > I'm copying in Paolo, Radim and Andrea- is there anyway we can make the
> > teardown of KVMs dirty tracking not take so long? 300ms is a silly long time
> > on only a small VM.
> > 
> > > >     I guess the biggest problem is that 300ms happens before we restart
> > > > the guest on the source if a migration fails.
> > > 
> > > 300ms happens even if a migration succeeds.
> > 
> > Hmm, OK, this needs fixing then - it does explain a result I saw a while
> > ago where the downtime was much bigger with libvirt than it was with
> > qemu on it's own.
> > 
> > > > > I think it can be optimized:
> > > > > (1) source vm will be destroyed if the migration is successfully done,
> > > > >       so the resources will be cleanuped automatically by the system
> > > > > (2) delay the cleanup if the migration failed
> > > > 
> > > > I don't like putting it in qmp_cont; that shouldn't have migration magic
> > > > in it.
> > > 
> > > Yes, it is not a ideal place. :(
> > > 
> > > > I guess we could put it in migrate_fd_cleanup perhaps? It gets called on
> > > > a bh near the end -  or could we just move it closer to the end of
> > > > migration_thread?
> > > 
> > > I have tested putting it in migrate_fd_cleanup, but the downtime is not
> > > optimized. So I think it is the same to move it closer to the end of
> > > migration_thread if it holds the BQL.
> > > Could we put it in migrate_init?
> > 
> > Your explanation above hints as to why migrate_fd_cleanup doesn't help;
> > it's because we're still going to be doing it with the BQL taken.
> 
> Yes, it is.
> 
> > Can you tell me which version of libvirt you're using?
> 
> I'm using 1.3.4
> 
> > I thought the newer ones were supposed to use events so they did't
> > have to poll qemu.
> 
> After checking the codes of the newest libvirt, I think it is the same
> in the qemuMigrationWaitForCompletion function, which is used to poll
> qemu every 50ms.

Checking with Jiri Denemark (added to cc), newer libvirt should use
events when available - but that polling code is there to cope with
older qemu's.  So with a newer qemu, i think it should spot the
COMPLETED event.

Dave

> Thanks,
> Jay
> 
> >   If we move qemu_savevm_state_cleanup is it still safe? Are there
> > some things we're supposed to do at that point which are wrong if
> > we don't.
> > 
> > I wonder about something like;  take a mutex in
> > memory_global_dirty_log_start, release it in
> > memory_global_dirty_log_stop.  Then make ram_save_cleanup start
> > a new thread that does the call to memory_global_dirty_log_stop.
> > 
> > Dave
> > 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Dr. David Alan Gilbert July 25, 2017, 7:15 p.m. UTC | #12
* Paolo Bonzini (pbonzini@redhat.com) wrote:
> On 24/07/2017 21:03, Dr. David Alan Gilbert wrote:
> >> I don't like having such a long-lived mutex (it seems like a recipe for
> >> deadlocks with the BQL), plus memory_region_transaction_commit (the
> >> expensive part of memory_global_dirty_log_stop) needs to be under the
> >> BQL itself because it calls MemoryListeners.
> >>
> >> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
> >> if it's called while runstate_running() returns false (which should be
> >> always the case)?
> >>
> >> It could even be entirely enclosed within memory.c if you do it with a
> >> VMChangeStateHandler.
> > This still causes the BQL to be held for quite a while; albeit at a less
> > critical point.
> > 
> > In this and the existing case we don't actually need efficiency - what we need is just
> > not to be holding onto the BQL for so long;  could we do a less
> > efficient commit here, removing one region at a time, yielding the lock
> > and retaking it?
> 
> I'm worried that if you release the lock and retake it you open a window
> where someone else could start a commit, and
> memory_global_dirty_log_stop's commit would use outdated information.
> 
> The problem is that a coarse lock, such as the BQL, is very hard to
> break into another lock with long critical sections (a "memory map
> commit lock" in this case).  It's obviously very easy to say "the new
> lock nests inside the BQL"... but then, because you created the lock to
> move things out of the BQL, any callback inside the new lock cannot take
> the memory map commit lock, and you need to make entire subsystems
> thread-safe.  If the new lock nests outside the BQL instead, it's
> simpler to avoid deadlocks, but you need to be careful about releasing
> the BQL and any reentrancy implications of doing that.
> 
> One strategy that worked well so far has been to use two locks, one of
> them being the BQL, where you can take either lock for reads and both
> for writes.

I guess you could say that in the event someone wants to do something
with the memory map they have to wait for the cleanup to complete?

From a bit of stracing though, it looks like even this isn't enough;
with a 70G VM:
we've got a worst case of about 150ms for any one region:
40430@1501009325.613214:kvm_log_stop_entry
40430@1501009325.760481:kvm_log_stop_exit

of which the actual ioctl is:
39925      0.000042 ioctl(11, KVM_SET_USER_MEMORY_REGION <unfinished ...>
...
39925      0.099510 <... ioctl resumed> , 0x7fb3d11fe660) = 0

about 100ms.

but the whole chunk of them is:

40430@1501009325.451807:kvm_log_stop_entry
40430@1501009325.451893:kvm_log_stop_exit
40430@1501009325.451899:kvm_log_stop_entry
.....<lots more>....
40430@1501009325.613214:kvm_log_stop_entry
40430@1501009325.760481:kvm_log_stop_exit

so that's about 310ms.

So:
  a) either way we've got 100ms in one syscall even if we could chop
this into separate operations; so it's still depressingly long.
  b) Is there anything we can do in the kernel to make it less
  expensive?
  c) Could we build a list of KVM_SET_USER_MEMORY_REGION calls
  that were needed, and perform these in the background
  while letting the rest of the world carry on?  Any changes
  cause us to have to wait for completion.
  d) If this is still something that Jay sees on the new libvirt
  then we need to do something; so doing it on runtype change seems
  OKish - but there again ~300ms to restart the VM if the migration
  fails is objectionable as well.

Dave

> Paolo
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Paolo Bonzini July 27, 2017, 2:26 p.m. UTC | #13
On 25/07/2017 21:15, Dr. David Alan Gilbert wrote:
> * Paolo Bonzini (pbonzini@redhat.com) wrote:
>> On 24/07/2017 21:03, Dr. David Alan Gilbert wrote:
>>>> I don't like having such a long-lived mutex (it seems like a recipe for
>>>> deadlocks with the BQL), plus memory_region_transaction_commit (the
>>>> expensive part of memory_global_dirty_log_stop) needs to be under the
>>>> BQL itself because it calls MemoryListeners.
>>>>
>>>> Maybe memory_global_dirty_log_stop can delay itself to the next vm_start
>>>> if it's called while runstate_running() returns false (which should be
>>>> always the case)?
>>>>
>>>> It could even be entirely enclosed within memory.c if you do it with a
>>>> VMChangeStateHandler.
>>> This still causes the BQL to be held for quite a while; albeit at a less
>>> critical point.
>>>
>>> In this and the existing case we don't actually need efficiency - what we need is just
>>> not to be holding onto the BQL for so long;  could we do a less
>>> efficient commit here, removing one region at a time, yielding the lock
>>> and retaking it?
>>
>> I'm worried that if you release the lock and retake it you open a window
>> where someone else could start a commit, and
>> memory_global_dirty_log_stop's commit would use outdated information.
>>
>> The problem is that a coarse lock, such as the BQL, is very hard to
>> break into another lock with long critical sections (a "memory map
>> commit lock" in this case).  It's obviously very easy to say "the new
>> lock nests inside the BQL"... but then, because you created the lock to
>> move things out of the BQL, any callback inside the new lock cannot take
>> the memory map commit lock, and you need to make entire subsystems
>> thread-safe.  If the new lock nests outside the BQL instead, it's
>> simpler to avoid deadlocks, but you need to be careful about releasing
>> the BQL and any reentrancy implications of doing that.
>>
>> One strategy that worked well so far has been to use two locks, one of
>> them being the BQL, where you can take either lock for reads and both
>> for writes.
> 
> I guess you could say that in the event someone wants to do something
> with the memory map they have to wait for the cleanup to complete?

Yes, you could take pending "invisible" changes (well, toggling dirty
bitmap status is the only invisible change to the guest I guess) and
push those to a separate thread.  That optimization would be in the KVM
memory listener.

Paolo
Zhoujian (jay) July 31, 2017, 7:04 a.m. UTC | #14
Hi Dave,

On 2017/7/25 18:34, Dr. David Alan Gilbert wrote:
>> After checking the codes of the newest libvirt, I think it is the same
>> in the qemuMigrationWaitForCompletion function, which is used to poll
>> qemu every 50ms.
>
> Checking with Jiri Denemark (added to cc), newer libvirt should use
> events when available - but that polling code is there to cope with
> older qemu's.  So with a newer qemu, i think it should spot the
> COMPLETED event.
>

I do tests on the newest libvirt(v3.6.0) + newest qemu(v2.9.90,
v2.10.0-rc0-29-ga588c49-dirty). The log added indicates that the source
side libvirt spots the COMPLETE event after the cleanup of the source side
qemu, i.e. 300ms still exists.

BTW, I'm not very familiar with libvirt, if there is something special to
configure or I'm missing something, please let me know.

Thanks,
Jay
Dr. David Alan Gilbert July 31, 2017, 1:33 p.m. UTC | #15
* Jay Zhou (jianjay.zhou@huawei.com) wrote:
> Hi Dave,
> 
> On 2017/7/25 18:34, Dr. David Alan Gilbert wrote:
> > > After checking the codes of the newest libvirt, I think it is the same
> > > in the qemuMigrationWaitForCompletion function, which is used to poll
> > > qemu every 50ms.
> > 
> > Checking with Jiri Denemark (added to cc), newer libvirt should use
> > events when available - but that polling code is there to cope with
> > older qemu's.  So with a newer qemu, i think it should spot the
> > COMPLETED event.
> > 
> 
> I do tests on the newest libvirt(v3.6.0) + newest qemu(v2.9.90,
> v2.10.0-rc0-29-ga588c49-dirty). The log added indicates that the source
> side libvirt spots the COMPLETE event after the cleanup of the source side
> qemu, i.e. 300ms still exists.

OK, thanks for trying it.
I don't quite understand why in this case - migration_completion sets
the state to COMPLETE and I think that's done outside the lock and that
happens a bit before the retaking of the lock and then the call
to the savevm_state_cleanup;  so yes, thanks for doing the test.

> BTW, I'm not very familiar with libvirt, if there is something special to
> configure or I'm missing something, please let me know.

I don't think you should need to.

Dave

> Thanks,
> Jay
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff mbox

Patch

diff --git a/migration/migration.c b/migration/migration.c
index a0db40d..72832be 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1877,6 +1877,15 @@  static void *migration_thread(void *opaque)
         if (qemu_file_get_error(s->to_dst_file)) {
             migrate_set_state(&s->state, current_active_state,
                               MIGRATION_STATUS_FAILED);
+            /*
+             * The resource has been allocated by migration will be reused in
+             * COLO process, so don't release them.
+             */
+            if (!enable_colo) {
+                qemu_mutex_lock_iothread();
+                qemu_savevm_state_cleanup();
+                qemu_mutex_unlock_iothread();
+            }
             trace_migration_thread_file_err();
             break;
         }
@@ -1916,13 +1925,6 @@  static void *migration_thread(void *opaque)
     end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
 
     qemu_mutex_lock_iothread();
-    /*
-     * The resource has been allocated by migration will be reused in COLO
-     * process, so don't release them.
-     */
-    if (!enable_colo) {
-        qemu_savevm_state_cleanup();
-    }
     if (s->state == MIGRATION_STATUS_COMPLETED) {
         uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
         s->total_time = end_time - s->total_time;
diff --git a/qmp.c b/qmp.c
index b86201e..0e68eaa 100644
--- a/qmp.c
+++ b/qmp.c
@@ -37,6 +37,8 @@ 
 #include "qom/object_interfaces.h"
 #include "hw/mem/pc-dimm.h"
 #include "hw/acpi/acpi_dev_interface.h"
+#include "migration/migration.h"
+#include "migration/savevm.h"
 
 NameInfo *qmp_query_name(Error **errp)
 {
@@ -200,6 +202,14 @@  void qmp_cont(Error **errp)
     if (runstate_check(RUN_STATE_INMIGRATE)) {
         autostart = 1;
     } else {
+        /*
+         * Delay the cleanup to reduce the downtime of migration.
+         * The resource has been allocated by migration will be reused
+         * in COLO process, so don't release them.
+         */
+        if (runstate_check(RUN_STATE_POSTMIGRATE) && !migrate_colo_enabled()) {
+            qemu_savevm_state_cleanup();
+        }
         vm_start();
     }
 }