[libvirt] [RFC v2 02/16] qemu: add memfd memory backing
marcandre.lureau at redhat.com
marcandre.lureau at redhat.com
Tue Aug 28 21:39:20 UTC 2018
From: Marc-André Lureau <marcandre.lureau at redhat.com>
Add a new memoryBacking source type "memfd", support by QEMU (when the
capability is available).
Sealing is enabled by default in qemu, and hugepage is easier to
setup, which makes it often a better choice than memory-backend-file.
Signed-off-by: Marc-André Lureau <marcandre.lureau at redhat.com>
---
docs/formatdomain.html.in | 8 ++-
docs/schemas/domaincommon.rng | 1 +
src/conf/domain_conf.c | 3 +-
src/conf/domain_conf.h | 1 +
src/qemu/qemu_command.c | 62 +++++++++++++------
tests/qemuxml2argvdata/memfd-memory-numa.args | 27 ++++++++
tests/qemuxml2argvdata/memfd-memory-numa.xml | 33 ++++++++++
tests/qemuxml2argvtest.c | 3 +
8 files changed, 116 insertions(+), 22 deletions(-)
create mode 100644 tests/qemuxml2argvdata/memfd-memory-numa.args
create mode 100644 tests/qemuxml2argvdata/memfd-memory-numa.xml
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index eb619a1656..ca656c9f7e 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -1099,7 +1099,7 @@
</hugepages>
<nosharepages/>
<locked/>
- <source type="file|anonymous"/>
+ <source type="file|anonymous|memfd"/>
<access mode="shared|private"/>
<allocation mode="immediate|ondemand"/>
<discard/>
@@ -1150,8 +1150,10 @@
suitable for the specific environment at the same time to mitigate
the risks described above. <span class="since">Since 1.0.6</span></dd>
<dt><code>source</code></dt>
- <dd>In this attribute you can switch to file memorybacking or keep
- default anonymous.</dd>
+ <dd>In this attribute you can switch to file memorybacking or
+ keep default anonymous. <span class="since">Since 4.8.0</span>,
+ you may choose <code>memfd</code> backing. (QEMU/KVM only)
+ </dd>
<dt><code>access</code></dt>
<dd>Specify if memory is shared or private. This can be overridden per
numa node by <code>memAccess</code></dd>
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 3796eb4b5e..04d7b69dd7 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -655,6 +655,7 @@
<choice>
<value>file</value>
<value>anonymous</value>
+ <value>memfd</value>
</choice>
</attribute>
</element>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 38cac07913..b3a1158e75 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -908,7 +908,8 @@ VIR_ENUM_IMPL(virDomainDiskMirrorState, VIR_DOMAIN_DISK_MIRROR_STATE_LAST,
VIR_ENUM_IMPL(virDomainMemorySource, VIR_DOMAIN_MEMORY_SOURCE_LAST,
"none",
"file",
- "anonymous")
+ "anonymous",
+ "memfd")
VIR_ENUM_IMPL(virDomainMemoryAllocation, VIR_DOMAIN_MEMORY_ALLOCATION_LAST,
"none",
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 8a3673361a..e72b824226 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -607,6 +607,7 @@ typedef enum {
VIR_DOMAIN_MEMORY_SOURCE_NONE = 0, /* No memory source defined */
VIR_DOMAIN_MEMORY_SOURCE_FILE, /* Memory source is set as file */
VIR_DOMAIN_MEMORY_SOURCE_ANONYMOUS, /* Memory source is set as anonymous */
+ VIR_DOMAIN_MEMORY_SOURCE_MEMFD, /* Memory source is set as memfd */
VIR_DOMAIN_MEMORY_SOURCE_LAST,
} virDomainMemorySource;
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 8aa20496bc..830695a147 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3100,6 +3100,24 @@ qemuBuildControllerDevCommandLine(virCommandPtr cmd,
return ret;
}
+static int
+qemuBuildMemoryBackendPropsShare(virJSONValuePtr props,
+ virDomainMemoryAccess memAccess)
+{
+ switch (memAccess) {
+ case VIR_DOMAIN_MEMORY_ACCESS_SHARED:
+ return virJSONValueObjectAdd(props, "b:share", true, NULL);
+
+ case VIR_DOMAIN_MEMORY_ACCESS_PRIVATE:
+ return virJSONValueObjectAdd(props, "b:share", false, NULL);
+
+ case VIR_DOMAIN_MEMORY_ACCESS_DEFAULT:
+ case VIR_DOMAIN_MEMORY_ACCESS_LAST:
+ break;
+ }
+
+ return 0;
+}
/**
* qemuBuildMemoryBackendProps:
@@ -3246,7 +3264,18 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
if (!(props = virJSONValueNewObject()))
return -1;
- if (useHugepage || mem->nvdimmPath || memAccess ||
+ if (def->mem.source == VIR_DOMAIN_MEMORY_SOURCE_MEMFD) {
+ backendType = "memory-backend-memfd";
+
+ if (qemuBuildMemoryBackendPropsShare(props, memAccess) < 0) {
+ goto cleanup;
+ }
+ if (useHugepage &&
+ (virJSONValueObjectAdd(props, "b:hugetlb", useHugepage, NULL) < 0 ||
+ virJSONValueObjectAdd(props, "U:hugetlbsize", pagesize << 10, NULL) < 0)) {
+ goto cleanup;
+ }
+ } else if (useHugepage || mem->nvdimmPath || memAccess ||
def->mem.source == VIR_DOMAIN_MEMORY_SOURCE_FILE) {
if (mem->nvdimmPath) {
@@ -3284,20 +3313,8 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
goto cleanup;
}
- switch (memAccess) {
- case VIR_DOMAIN_MEMORY_ACCESS_SHARED:
- if (virJSONValueObjectAdd(props, "b:share", true, NULL) < 0)
- goto cleanup;
- break;
-
- case VIR_DOMAIN_MEMORY_ACCESS_PRIVATE:
- if (virJSONValueObjectAdd(props, "b:share", false, NULL) < 0)
- goto cleanup;
- break;
-
- case VIR_DOMAIN_MEMORY_ACCESS_DEFAULT:
- case VIR_DOMAIN_MEMORY_ACCESS_LAST:
- break;
+ if (qemuBuildMemoryBackendPropsShare(props, memAccess) < 0) {
+ goto cleanup;
}
} else {
backendType = "memory-backend-ram";
@@ -3346,6 +3363,12 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
_("this qemu doesn't support the "
"memory-backend-ram object"));
goto cleanup;
+ } else if (STREQ(backendType, "memory-backend-memfd") &&
+ !virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD)) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+ _("this qemu doesn't support the "
+ "memory-backend-memfd object"));
+ goto cleanup;
}
ret = 0;
@@ -7650,7 +7673,8 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
if (virDomainNumatuneHasPerNodeBinding(def->numa) &&
!(virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_RAM) ||
- virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE))) {
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE) ||
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Per-node memory binding is not supported "
"with this QEMU"));
@@ -7659,7 +7683,8 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
if (def->mem.nhugepages &&
def->mem.hugepages[0].size != system_page_size &&
- !virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE)) {
+ !(virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE) ||
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("huge pages per NUMA node are not "
"supported with this QEMU"));
@@ -7676,7 +7701,8 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
* need to check which approach to use */
for (i = 0; i < ncells; i++) {
if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_RAM) ||
- virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE)) {
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE) ||
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD)) {
if ((rc = qemuBuildMemoryCellBackendStr(def, cfg, i, priv,
&nodeBackends[i])) < 0)
diff --git a/tests/qemuxml2argvdata/memfd-memory-numa.args b/tests/qemuxml2argvdata/memfd-memory-numa.args
new file mode 100644
index 0000000000..04b28a8085
--- /dev/null
+++ b/tests/qemuxml2argvdata/memfd-memory-numa.args
@@ -0,0 +1,27 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-x86_64 \
+-name instance-00000092 \
+-S \
+-machine pc-i440fx-wily,accel=kvm,usb=off,dump-guest-core=off \
+-m 14336 \
+-mem-prealloc \
+-smp 20,sockets=1,cores=8,threads=1 \
+-object memory-backend-memfd,id=ram-node0,share=yes,hugetlb=yes,hugetlbsize=2097152,size=15032385536 \
+-numa node,nodeid=0,cpus=0-7,memdev=ram-node0 \
+-uuid 126f2720-6f8e-45ab-a886-ec9277079a67 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,\
+path=/tmp/lib/domain--1-instance-00000092/monitor.sock,server,nowait \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-no-acpi \
+-usb \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
diff --git a/tests/qemuxml2argvdata/memfd-memory-numa.xml b/tests/qemuxml2argvdata/memfd-memory-numa.xml
new file mode 100644
index 0000000000..868e3c765f
--- /dev/null
+++ b/tests/qemuxml2argvdata/memfd-memory-numa.xml
@@ -0,0 +1,33 @@
+ <domain type='kvm' id='56'>
+ <name>instance-00000092</name>
+ <uuid>126f2720-6f8e-45ab-a886-ec9277079a67</uuid>
+ <memory unit='KiB'>14680064</memory>
+ <currentMemory unit='KiB'>14680064</currentMemory>
+ <memoryBacking>
+ <hugepages>
+ <page size="2" unit="M"/>
+ </hugepages>
+ <source type='memfd'/>
+ <access mode='shared'/>
+ <allocation mode='immediate'/>
+ </memoryBacking>
+ <vcpu placement='static'>20</vcpu>
+ <os>
+ <type arch='x86_64' machine='pc-i440fx-wily'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <cpu>
+ <topology sockets='1' cores='8' threads='1'/>
+ <numa>
+ <cell id='0' cpus='0-7' memory='14680064' unit='KiB'/>
+ </numa>
+ </cpu>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-x86_64</emulator>
+ <memballoon model='virtio'/>
+ </devices>
+ </domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 16c3540798..84edbe7230 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -2921,6 +2921,9 @@ mymain(void)
DO_TEST("fd-memory-no-numa-topology", QEMU_CAPS_OBJECT_MEMORY_FILE,
QEMU_CAPS_KVM);
+ DO_TEST("memfd-memory-numa", QEMU_CAPS_OBJECT_MEMORY_MEMFD,
+ QEMU_CAPS_KVM);
+
DO_TEST("cpu-check-none", QEMU_CAPS_KVM);
DO_TEST("cpu-check-partial", QEMU_CAPS_KVM);
DO_TEST("cpu-check-full", QEMU_CAPS_KVM);
--
2.19.0.rc0.48.gb9dfa238d5
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