Rewrite the code to improve maintainability and also re-do construction
of error messages which are assembled from non-translatable parts.
Closes: https://gitlab.com/libvirt/libvirt/-/issues/455
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Detected by gcc 11 -Wformat-overflow:
../../src/util/vircgroupv1.c: In function ‘virCgroupV1ValidatePlacement’:
../../src/util/virerror.h:176:5: warning: ‘%s’ directive argument is null [-Wformat-overflow=]
176 | virReportErrorHelper(VIR_FROM_THIS, code, __FILE__, \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
177 | __FUNCTION__, __LINE__, __VA_ARGS__)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../src/util/vircgroupv1.c:411:13: note: in expansion of macro ‘virReportError’
411 | virReportError(VIR_ERR_INTERNAL_ERROR,
| ^~~~~~~~~~~~~~
../../src/util/vircgroupv1.c:412:80: note: format string is defined here
412 | _("Could not find placement for v1 controller %s at %s"),
| ^~
Signed-off-by: Scott Davis <scott.davis@starlab.io>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In some cases we have a label that contains nothing but a return
statement. The amount of such labels rises as we use automagic
cleanup. Anyway, such labels are pointless and can be dropped.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
I've encountered the following bug, but only on Gentoo with
systemd and CGroupsV2. I've started an LXC container successfully
but destroying it reported the following error:
error: Failed to destroy domain 'amd64'
error: internal error: failed to get cgroup backend for 'pathOfController'
Debugging showed, that CGroup hierarchy is full of surprises:
/sys/fs/cgroup/machine.slice/machine-lxc\x2d861\x2damd64.scope/
└── libvirt
├── dev-hugepages.mount
├── dev-mqueue.mount
├── init.scope
├── sys-fs-fuse-connections.mount
├── sys-kernel-config.mount
├── sys-kernel-debug.mount
├── sys-kernel-tracing.mount
├── system.slice
│ ├── console-getty.service
│ ├── dbus.service
│ ├── system-getty.slice
│ ├── system-modprobe.slice
│ ├── systemd-journald.service
│ ├── systemd-logind.service
│ └── tmp.mount
└── user.slice
For comparison, here's the same container on recent Rawhide:
/sys/fs/cgroup/machine.slice/machine-lxc\x2d13550\x2damd64.scope/
└── libvirt
Anyway, those nested directories should not be a problem, because
virCgroupKillRecursiveInternal() removes them recursively, right?
Sort of. The function really does remove nested directories, but
it assumes that every directory has the same controller as the
rest. Just take a look at virCgroupV2KillRecursive() - it gets
'Any' controller (the first one it found in ".scope") and then
passes it to virCgroupKillRecursiveInternal().
This assumption is not true though. The controllers found in
".scope" are the following:
cpuset cpu io memory pids
while "libvirt" has fewer:
cpuset cpu io memory
Up until now it's not problem, because of how we order
controllers internally - "cpu" is the first and thus picking
"Any" controller returns just that. But the rest of directories
has no controllers, their "cgroup.controllers" is just empty.
What fixes the bug is dropping @controller argument from
virCgroupKillRecursiveInternal() and letting each iteration work
pick its own controller.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Historically, we declared pointer type to our types:
typedef struct _virXXX virXXX;
typedef virXXX *virXXXPtr;
But usefulness of such declaration is questionable, at best.
Unfortunately, we can't drop every such declaration - we have to
carry some over, because they are part of public API (e.g.
virDomainPtr). But for internal types - we can do drop them and
use what every other C project uses 'virXXX *'.
This change was generated by a very ugly shell script that
generated sed script which was then called over each file in the
repository. For the shell script refer to the cover letter:
https://listman.redhat.com/archives/libvir-list/2021-March/msg00537.html
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Generated using the following spatch:
@@
expression path;
@@
- virFileMakePath(path)
+ g_mkdir_with_parents(path, 0777)
However, 14 occurrences were not replaced, e.g. in
virHostdevManagerNew(). I don't really understand why.
Fixed by hand afterwards.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Before the conversion to using systemd DBus API to set the cpu.shares
there was some magic conversion done by kernel which was documented in
virsh manpage as well. Now systemd errors out if the value is out of
range.
Since we enforce the range for other cpu cgroup attributes 'quota' and
'period' it makes sense to do the same for 'shares' as well.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When running on host with systemd we register VMs with machined.
In this case systemd creates the root VM cgroup for us. This has some
implications where one of them is that systemd owns all files inside
the root VM cgroup and we should not touch them.
We already use DBus calls for some of the APIs but for the remaining
ones we will continue accessing the files directly. Systemd doesn't
support threaded cgroups so we need to do this.
The reason why we don't use DBus for most of the APIs is that we already
have a code that works with files and we would have to check if systemd
supports each API.
This change introduces new topology on systemd hosts:
$ROOT
|
+- machine.slice
|
+- machine-qemu\x2d1\x2dvm1.scope
|
+- libvirt
|
+- emulator
+- vcpu0
+- vcpu0
compared to the previous topology:
$ROOT
|
+- machine.slice
|
+- machine-qemu\x2d1\x2dvm1.scope
|
+- emulator
+- vcpu0
+- vcpu0
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This will check if the cgroup actually exists on the system.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When we create a new child cgroup and the parent cgroup has any process
attached to it enabling controllers for the child cgroup fails with
error. We need to move the process into the child cgroup first before
enabling any controllers.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Remove one level of indentation by splitting the condition.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When running on host with systemd we register VMs with machined.
In this case systemd creates the root VM cgroup for us. This has some
implications where one of them is that systemd owns all files inside
the root VM cgroup and we should not touch them.
If we change any value in file that systemd knows about it will be
changed to what systemd thinks it should be when executing
`systemctl daemon-reload`.
These are the APIs that we need to call using systemd because they set
limits that are proportional to sibling cgroups.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
All these headers are indirectly included provided by virfile.h having
virstoragefile.h which will be removed in the following patch.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Now that every caller to copyPlacement doesn't pass absolute path there
is no need to have a condition to handle that case.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Currently this task is done by virCgroupCopyPlacement when the @path
starts with "/".
virCgroupNew is always called with @path starting with "/" and there is
no parent to copy path from. To make it obvious what the code is doing
introduce new helper.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
It is only used for debug and error purposes which can be easily
replaced by @placement.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
All of these conversions are trivial - VIR_DIR_CLOSE() (aka
virDirClose()) is called only once on the DIR*, and it happens just
before going out of scope.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
DIR *dh is being re-used each time through the for loop of this
function, so it must be closed and then re-opened, which means we
can't convert it to g_autoptr. By moving the definition of dh inside
the for loop, we make it possible to trivially convert to g_autoptr
(which will happen in a subsequent patch)
NB: VIR_DIR_CLOSE() is already called at the bottom of the for loop,
so removing the VIR_DIR_CLOSE() at the end of the function is *not*
creating a leak of a DIR*!
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Rewrite using GHashTable which already has interfaces for using a number
as hash key. Glib's implementation doesn't copy the key by default, so
we need to allocate it, but overal the interface is more suited for this
case.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
As preparation for g_autoptr() we need to change the function to take
only virCgroupPtr.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Jonathon Jongsma <jjongsma@redhat.com>
There is nothing in the vircgroup.h header file
requiring virutil.h.
Remove it and include unistd.h in the C files.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The GLib g_lstat() function provides a portable impl for
Win32.
Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
So the issue here is that you can end up with configuration where
you have cgroup v1 and v2 enabled at the same time and the devices
controllers is enabled for cgroup v1.
In cgroup v2 there is no devices controller, the device access is
controlled using BPF and since it is not a cgroup controller both
of them can exists at the same time and both of them are applied while
resolving access to devices.
In order to avoid configuring both BPF and cgroup v1 devices we will
use BPF if possible and otherwise fallback to cgroup v1 devices.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In few places we have the following code pattern:
int ret;
... /* @ret is not accessed here */
ret = f(...);
return ret;
This pattern can be written less verbose:
...
return f(...);
This patch was generated with following coccinelle spatch:
@@
type T;
constant C;
expression f;
identifier ret;
@@
-T ret = C;
... when != ret
-ret = f;
-return ret;
+return f;
Afterwards I needed to fix a few places, e.g. comment in
virDomainNetIPParseXML() was removed too because coccinelle
thinks it refers to @ret while in fact it doesn't. Also in few
places it replaced @ret declaration with a few spaces instead of
removing the line. But nothing terribly wrong.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Replace all occurrences of
if (VIR_STRDUP(a, b) < 0)
/* effectively dead code */
with:
a = g_strdup(b);
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since commit 44e7f02915
util: rewrite auto cleanup macros to use glib's equivalent
VIR_AUTOFREE is just an alias for g_autofree. Use the GLib macros
directly instead of our custom aliases.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Use G_GNUC_UNUSED from GLib instead of ATTRIBUTE_UNUSED.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When creating new group for cgroups v2 the we cannot check
cgroups.controllers for that cgroup because the directory is created
later. In that case we should check cgroups.subtree_control of parent
group to get list of controllers enabled for child cgroups.
In order to achieve that we will prefer the parent group if it exists,
the current group will be used only for root group.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
This reverts commit 7bca1c9bdc.
As it turns out it's not a good idea on systemd hosts. The root
cgroup can have all controllers enabled but they don't have to be
enabled for sub-cgroups.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This affects only cgroups v2 where enabled controllers are not based on
available mount points but on the list provided in cgroup.controllers
file. However, moving it will fill in placement as well, so it needs
to be freed together with mount point if we don't need that controller.
Before this patch we were assuming that all controllers available in
root cgroup where available in all other sub-cgroups which was wrong.
In order to fix it we need to move the cgroup controllers detection
after cgroup placement was prepared in order to build correct path for
cgroup.controllers file.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
In cgroups v2 we don't have to detect available controllers every single
time if we are creating a new cgroup based on parent cgroup.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In kernel 4.12 there was introduced new BFQ scheduler and in kernel
5.0 the old CFQ scheduler was removed. This has an implication on
the cgroups file names.
If the CFQ controller is enabled we use these two files:
blkio.weight
blkio.weight_device
The new BFQ controller expose only one file with different name:
blkio.bfq.weight
The reason is that BFQ controller doesn't support per-device weight.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
If we need to get a path of specific file and we need to check its
existence before we use it then we can reuse that path to get value
for specific device. This way we will not build the path again in
virCgroupGetValueForBlkDev.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Standardize on putting the _LAST enum value on the second line
of VIR_ENUM_IMPL invocations. Later patches that add string labels
to VIR_ENUM_IMPL will push most of these to the second line anyways,
so this saves some noise.
Signed-off-by: Cole Robinson <crobinso@redhat.com>
This reverts commit a5e1602090.
Getting rid of unistd.h from our headers will require more work than
just fixing the broken mingw build. Revert it until I have a more
complete proposal.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
util/virutil.h bogously included unistd.h. Drop it and replace it by
including it directly where needed.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
'viralloc.h' does not provide any type or macro which would be necessary
in headers. Prevent leakage of the inclusion.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_IMPL calls.
Move the verify() statement to the end of the macro and drop
the semicolon, so the compiler will require callers to add a
semicolon.
While we are touching these call sites, standardize on putting
the closing parenth on its own line, as discussed here:
https://www.redhat.com/archives/libvir-list/2019-January/msg00750.html
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
