[libvirt] [PATCH] qemu: Don't try to use hugepages if not enabled

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1214369

My fix 671d18594f4 was incomplete. If domain doesn't have
hugepages enalbed, because of missing condition we would still be
putting hugepages path onto qemu cmd line. Clean up the
conditions so that it's more visible next time.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_command.c                            | 12 +++++-----
 .../qemuxml2argv-cpu-numa-memshared.args           | 26 ++++++++++++++++++++++
 tests/qemuxml2argvtest.c                           |  1 +
 3 files changed, 33 insertions(+), 6 deletions(-)
 create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-cpu-numa-memshared.args

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 3e1552a1b..8c12b2be0 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3408,23 +3408,23 @@ qemuBuildMemoryBackendStr(virJSONValuePtr *backendProps,
 
     if (pagesize || mem->nvdimmPath || memAccess ||
         def->mem.source == VIR_DOMAIN_MEMORY_SOURCE_FILE) {
         *backendType = "memory-backend-file";
 
-        if (mem->nvdimmPath) {
+        if (pagesize) {
+            if (qemuGetDomainHupageMemPath(def, cfg, pagesize, &memPath) < 0)
+                goto cleanup;
+            prealloc = true;
+        } else if (mem->nvdimmPath) {
             if (VIR_STRDUP(memPath, mem->nvdimmPath) < 0)
                 goto cleanup;
             prealloc = true;
-        } else if (!pagesize && def->mem.source == VIR_DOMAIN_MEMORY_SOURCE_FILE) {
+        } else {
             /* We can have both pagesize and mem source. If that's the case,
              * prefer hugepages as those are more specific. */
             if (VIR_STRDUP(memPath, cfg->memoryBackingDir) < 0)
                 goto cleanup;
-        } else {
-            if (qemuGetDomainHupageMemPath(def, cfg, pagesize, &memPath) < 0)
-                goto cleanup;
-            prealloc = true;
         }
 
         if (virJSONValueObjectAdd(props,
                                   "B:prealloc", prealloc,
                                   "s:mem-path", memPath,
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-numa-memshared.args b/tests/qemuxml2argvdata/qemuxml2argv-cpu-numa-memshared.args
new file mode 100644
index 000000000..cceffce3a
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-numa-memshared.args
@@ -0,0 +1,26 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-x86_64 \
+-name QEMUGuest1 \
+-S \
+-M pc \
+-m 214 \
+-smp 16,sockets=2,cores=4,threads=2 \
+-object memory-backend-file,id=ram-node0,mem-path=/var/lib/libvirt/qemu/ram,\
+share=yes,size=112197632 \
+-numa node,nodeid=0,cpus=0-7,memdev=ram-node0 \
+-object memory-backend-file,id=ram-node1,mem-path=/var/lib/libvirt/qemu/ram,\
+share=no,size=112197632 \
+-numa node,nodeid=1,cpus=8-15,memdev=ram-node1 \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-nographic \
+-nodefaults \
+-monitor unix:/tmp/lib/domain--1-QEMUGuest1/monitor.sock,server,nowait \
+-no-acpi \
+-boot n \
+-usb \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 43d3f1bd3..799aea9fa 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -1539,10 +1539,11 @@ mymain(void)
     DO_TEST_PARSE_ERROR("cpu-numa3", NONE);
     DO_TEST_FAILURE("cpu-numa-disjoint", NONE);
     DO_TEST("cpu-numa-disjoint", QEMU_CAPS_NUMA);
     DO_TEST_FAILURE("cpu-numa-memshared", QEMU_CAPS_OBJECT_MEMORY_RAM);
     DO_TEST_FAILURE("cpu-numa-memshared", NONE);
+    DO_TEST("cpu-numa-memshared", QEMU_CAPS_OBJECT_MEMORY_FILE);
     DO_TEST("cpu-host-model", NONE);
     DO_TEST("cpu-host-model-vendor", NONE);
     skipLegacyCPUs = true;
     DO_TEST("cpu-host-model-fallback", NONE);
     DO_TEST_FAILURE("cpu-host-model-nofallback", NONE);
-- 
2.13.0