The code that calls virCgroupSetCpuShares() and virCgroupGetCpuShares()
is repeated in 4 different places. Let's put it in a new
virCgroupSetupCpuShares() to avoid code repetition.
There's a reason of why we execute a Get in the same value we
just executed Set, explained in detail by commit 97814d8ab3.
Let's add a gist of the reasoning behind it as a comment in
this new function as well.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The code from qemuSetupCgroupCpusetCpus() and virLXCCgroupSetupCpusetTune()
can be centralized in a new helper called virCgroupSetupCpusetCpus().
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Previous patch moved all duplicated code that were setting
and getting BlkioDevice parameters to vircgroup.c. We can
turn them into static and spare a few symbols in
libvirt_private.syms.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The current use of the functions that set and get
BlkioDevice attributes is doing a set(), followed by
a get() of the same parameter right after. This is done
because there is no guarantee that the kernel will accept
the desired value given by the set() call, thus we need to
execute a get() right after to get the actual value.
This patch adds helpers inside vircgroup.c to execute these
operations. Next patch will use these helpers to reduce
code repetition in LXC and QEMU files.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
G_STATIC_ASSERT() is a drop-in functional equivalent of
the GNULIB verify() macro.
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Some VM configurations may result in a large number of threads created by
the associated qemu process which can exceed the system default limit. The
maximum number of threads allowed per process is controlled by the pids
cgroup controller and is set to 16k when creating VMs with systemd's
machined service. The maximum number of threads per process is recorded
in the pids.max file under the machine's pids controller cgroup hierarchy,
e.g.
$cgrp-mnt/pids/machine.slice/machine-qemu\\x2d1\\x2dtest.scope/pids.max
Maximum threads per process is controlled with the TasksMax property of
the systemd scope for the machine. This patch adds an option to qemu.conf
which can be used to override the maximum number of threads allowed per
qemu process. If the value of option is greater than zero, it will be set
in the TasksMax property of the machine's scope after creating the machine.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
virutil.(c|h) is a very gross collection of random code. Remove the enum
handlers from there so we can limit the scope where virtutil.h is used.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Once we introduce cgroup v2 support we need to handle processes and
threads differently.
Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
In cgroup v2 we need to handle processes and threads differently,
following patch will introduce virCgroupAddThread.
Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
The case where we need path of any controller is only for internal use
so move it out to a different function.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
This reverts commit 0f80c71822.
Turns out, our code relies on virCgroupFree(&var) setting
var = NULL.
Conflicts:
src/util/vircgroup.c: context because 94f1855f09 is not
reverted.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
This reverts commit 4da4a9fe0c.
Turns out, our code relies on virCgroupFree(&var) setting
var = NULL.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Using the new VIR_DEFINE_AUTOPTR_FUNC macro defined in
src/util/viralloc.h, define a new wrapper around an existing
cleanup function which will be called when a variable declared
with VIR_AUTOPTR macro goes out of scope. Also, drop the redundant
viralloc.h include, since that has moved from the source module into
the header.
When a variable of type virCgroupPtr is declared using
VIR_AUTOPTR, the function virCgroupFree will be run
automatically on it when it goes out of scope.
This commit also adds an intermediate typedef for virCgroup
type for use with the cleanup macros.
Signed-off-by: Sukrit Bhatnagar <skrtbhtngr@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Modify virCgroupFree function signature to take a value of type
virCgroupPtr instead of virCgroupPtr * as the parameter.
Change the argument type in all calls to virCgroupFree function
from virCgroupPtr * to virCgroupPtr. This is a step towards
having consistent function signatures for Free helpers so that
they can be used with VIR_AUTOPTR cleanup macro.
Signed-off-by: Sukrit Bhatnagar <skrtbhtngr@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
It is more related to a domain as we might use it even when there is
no systemd and it does not use any dbus/systemd functions. In order
not to use code from conf/ in util/ pass machineName in cgroups code
as a parameter. That also fixes a leak of machineName in the lxc
driver and cleans up and de-duplicates some code.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Currently when spawning containers with systemd, the container PID 1
will get moved into the systemd machine slice. Libvirt then manually
moves the libvirt_lxc and qemu-nbd processes into the cgroups associated
with the slice, but skips the systemd controller cgroup. This means that
from systemd's POV, libvirt_lxc and qemu-nbd are still part of the
libvirtd.service unit.
On systemctl daemon-reload, it will notice that libvirt_lxc & qemu-nbd
are in the libvirtd.service unit for the systemd controller, but in the
machine cgroups for resources. Systemd will thus move them back into
the libvirtd.service resource cgroups next time libvirtd is restarted.
This causes libvirtd to kill off the container due to incorrect cgroup
placement.
The solution is to ensure that when moving libvirt_lxc & qemu-nbd, we
also move the systemd cgroup controller placement. Normally this is
not something we ever want todo, but this is a special case as we are
intentionally wanting to move them to a different systemd unit.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
qemuProcessSetupEmulator runs at a point in time where there is only
the qemu main thread. Use virCgroupAddTask to put just that one task
into the emulator cgroup. That patch makes virCgroupMoveTask and
virCgroupAddTaskStrController obsolete.
Signed-off-by: Henning Schild <henning.schild@siemens.com>
When adding disk images to ACL we may call those functions on NFS
shares. In that case we might get an EACCES, which isn't really relevant
since NFS would not hold a block device. This patch adds a flag that
allows to stop reporting an error on EACCES to avoid spaming logs.
Currently there's no functional change.
Since commit 47e5b5ae virCgroupAllowDevice allows to pass -1 as either
the minor or major device number and it automatically uses '*' in place
of that. Reuse the new approach through the code and drop the duplicated
functions.
So, systemd-machined has this philosophy that machine names are like
hostnames and hence should follow the same rules. But we always allowed
international characters in domain names. Thus we need to modify the
machine name we are passing to systemd.
In order to change some machine names that we will be passing to systemd,
we also need to call TerminateMachine at the end of a lifetime of a
domain. Even for domains that were started with older libvirt. That
can be achieved thanks to virSystemdGetMachineNameByPID(). And because
we can change machine names, we can get rid of the inconsistent and
pointless escaping of domain names when creating machine names.
So this patch modifies the naming in the following way. It creates the
name as <drivername>-<id>-<name> where invalid hostname characters are
stripped out of the name and if the resulting name is longer, it
truncates it to 64 characters. That way we can start domains we
couldn't start before. Well, at least on systemd.
To make it work all together, the machineName (which is needed only with
systemd) is saved in domain's private data. That way the generation is
moved to the driver and we don't need to pass various unnecessary
arguments to cgroup functions.
The only thing this complicates a bit is the scope generation when
validating a cgroup where we must check both old and new naming, so a
slight modification was needed there.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1282846
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
On the host when we start a container, it will be
placed in a cgroup path of
/machine.slice/machine-lxc\x2ddemo.scope
under /sys/fs/cgroup/*
Inside the containers' namespace we need to setup
/sys/fs/cgroup mounts, and currently will bind
mount /machine.slice/machine-lxc\x2ddemo.scope on
the host to appear as / in the container.
While this may sound nice, it confuses applications
dealing with cgroups, because /proc/$PID/cgroup
now does not match the directory in /sys/fs/cgroup
This particularly causes problems for systems and
will make it create repeated path components in
the cgroup for apps run in the container eg
/machine.slice/machine-lxc\x2ddemo.scope/machine.slice/machine-lxc\x2ddemo.scope/user.slice/user-0.slice/session-61.scope
This also causes any systemd service that uses
sd-notify to fail to start, because when systemd
receives the notification it won't be able to
identify the corresponding unit it came from.
In particular this break rabbitmq-server startup
Future kernels will provide proper cgroup namespacing
which will handle this problem, but until that time
we should not try to play games with hiding parent
cgroups.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The scope name, even according to our docs is
"machine-$DRIVER\x2d$VMNAME.scope" virSystemdMakeScopeName would use the
resource partition name instead of "machine-" if it was specified thus
creating invalid scope paths.
This makes libvirt drop cgroups for a VM that uses custom resource
partition upon reconnecting since the detected scope name would not
match the expected name generated by virSystemdMakeScopeName.
The error is exposed by the following log entry:
debug : virCgroupValidateMachineGroup:302 : Name 'machine-qemu\x2dtestvm.scope' for controller 'cpu' does not match 'testvm', 'testvm.libvirt-qemu' or 'machine-test-qemu\x2dtestvm.scope'
for a "/machine/test" resource and "testvm" vm.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1238570
Create a new common API to replace the virCgroupNew{Vcpu|Emulator|IOThread}
API's using an emum to generate the cgroup name
Signed-off-by: John Ferlan <jferlan@redhat.com>
This new internal API checks if given CGroup controller is
available. It is going to be needed later when we need to make a
decision whether pin domain memory onto NUMA nodes using cpuset
CGroup controller or using numa_set_membind().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Throughout our code, the virCgroupController enum is used in two ways.
First as an index to an array of cgroup controllers:
struct virCgroup {
char *path;
struct virCgroupController controllers[VIR_CGROUP_CONTROLLER_LAST];
};
Second way is that when calling virCgroupNew() a bitmask of the enum
items can be passed to selectively detect only some controllers. For
instance:
int
virCgroupNewVcpu(virCgroupPtr domain,
int vcpuid,
bool create,
virCgroupPtr *group)
{
...
controllers = ((1 << VIR_CGROUP_CONTROLLER_CPU) |
(1 << VIR_CGROUP_CONTROLLER_CPUACCT) |
(1 << VIR_CGROUP_CONTROLLER_CPUSET));
if (virCgroupNew(-1, name, domain, controllers, group) < 0)
goto cleanup;
}
Even though it's highly unlikely that so many new controllers will be
invented so that we would overflow when constructing the bitmask, it
doesn't hurt to check at compile time either.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
systemd-machined introduced a new method CreateMachineWithNetwork
that obsoletes CreateMachine. It expects to be given a list of
VETH/TAP device indexes for the host side device(s) associated
with a container/machine.
This falls back to the old CreateMachine method when the new
one is not supported.
If we don't properly clean up all processes in the
machine-<vmname>.scope systemd won't remove the cgroup and subsequent vm
starts fail with
'CreateMachine: File exists'
Additional processes can e.g. be added via
echo $PID > /sys/fs/cgroup/systemd/machine.slice/machine-${VMNAME}.scope/tasks
but there are other cases like
http://bugs.debian.org/761521
Invoke TerminateMachine to be on the safe side since systemd tracks the
cgroup anyway. This is a noop if all processes have terminated already.
Added <capabilities> in the <features> section of LXC domains
configuration. This section can contain elements named after the
capabilities like:
<mknod state="on"/>, keep CAP_MKNOD capability
<sys_chroot state="off"/> drop CAP_SYS_CHROOT capability
Users can restrict or give more capabilities than the default using
this mechanism.
Cgroups code uses VIR_CGROUP_DEVICE_* flags to specify the mode but in
the end it needs to be converted to a string. Add a helper to do it and
use it in the cgroup code before introducing it into the rest of the
code.
Currently, virCgroupGetPercpuStats is only used by the LXC driver,
filling out the CPUTIME stats. qemuDomainGetPercpuStats does this
and also filles out VCPUTIME stats.
Extend virCgroupGetPercpuStats to also report VCPUTIME stats if
nvcpupids is non-zero. In the LXC driver, we don't have cpupids.
In the QEMU driver, there is at least one cpupid for a running domain,
so the behavior shouldn't change for QEMU either.
Also rename getSumVcpuPercpuStats to virCgroupGetPercpuVcpuSum.
This function is needed for user namespaces, where we need to chmod()
the cgroup to the initial uid/gid such that systemd is allowed to
use the cgroup.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
