https://bugzilla.redhat.com/show_bug.cgi?id=1480668
QEMU has this new feature memory-backend-file.discard-data=yes
which is a nifty optimization. Basically, when qemu is quitting
or on memory hotplug it calls munmap() and close() on the file
that is backing the memory. However, this does not mean kernel
won't stop touching that part of memory. It still might. With
this feature enabled we tell kernel: "we don't need this memory
nor data stored in it". This makes kernel drop the memory
immediately without trying to sync memory with the mapped file.
Unfortunately, this cannot be turned on by default because we
can't be sure when users really don't care about what happens to
data after qemu dies. So it has to be opt-in. As usual, there are
three places where one can configure memory attributes. This
patch adds the feature to all of them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Implied by QEMU >= 1.2.0.
Delete this one first, because QEMU_CAPS_NODEFCONFIG is only used
when QEMU_CAPS_NO_USER_CONFIG is unsupported.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
We require QEMU >= 1.5.0, assume every QEMU supports it.
Sadly that does not let us trivially drop qemuMonitor's
priv->monJSON bool, because of qemuDomainQemuAttach.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Similarly to the previous commit, rename .args files.
The files were renamed using the following commands. From
qemuxml2argvdata:
for i in qemuxml2argv-*.args; do mv $i ${i#qemuxml2argv-}; done
and then (to fix broken symlinks) from qemuxml2argvdata and
qemuxml2xmloutdata:
for i in $(find . -xtype l); do \
ln -sf $(readlink $i | sed 's/qemuxml2argv-//') $i;
done
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>