Commit Graph

266 Commits

Author SHA1 Message Date
Roman Bogorodskiy
c419e9b51c cgroup macros refactoring, part 2
- Convert virCgroupGet* to VIR_CGROUP_SUPPORTED
- Convert virCgroup(Get|Set)FreezerState to VIR_CGROUP_SUPPORTED

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-12 16:58:47 -06:00
Roman Bogorodskiy
02f1fd41f6 cgroup macros refactoring, part 1
- Introduce VIR_CGROUP_SUPPORTED conditional
- Convert virCgroupKill* to use it
- Convert virCgroupIsolateMount() to use it
- Convert virCgroupRemoveRecursively to VIR_CGROUP_SUPPORTED

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-12 16:15:58 -06:00
Eric Blake
2ff9e54cbf cgroup: functional sort
Make future patches smaller by matching a sane header listing in
the first place.  No semantic change.

* src/util/vircgroup.h: Move free next to new, and controller
functions next to each other.
* src/util/vircgroup.c (virCgroupFree, virCgroupHasController)
(virCgroupPathOfController, virCgroupRemoveRecursively)
(virCgroupRemove): Sort implementation to be closer to header.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-12 16:08:18 -06:00
Eric Blake
7ccd322b20 cgroup: topological sort
Avoid a forward declaration of a static function.

* src/util/vircgroup.c (virCgroupPartitionNeedsEscaping)
(virCgroupParticionEscape): Move up.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-12 15:38:37 -06:00
Eric Blake
a91929053c cgroup: use consistent formatting
Format all functions with two blank lines between, and return type
on separate line from function name.  Also break some lines longer
than 80 columns.  This makes the subsequent macro refactoring
less noisy.

* src/util/vircgroup.c: Match prevailing style.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-12 15:36:35 -06:00
Daniel P. Berrange
2fe2470181 Enable support for systemd-machined in cgroups creation
Make the virCgroupNewMachine method try to use systemd-machined
first. If that fails, then fallback to using the traditional
cgroup setup code path.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-31 19:29:19 +01:00
Daniel P. Berrange
75304eaa1a Cope with races while killing processes
When systemd is involved in managing processes, it may start
killing off & tearing down croups associated with the process
while we're still doing virCgroupKillPainfully. We must
explicitly check for ENOENT and treat it as if we had finished
killing processes

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-31 19:27:28 +01:00
Daniel P. Berrange
aedd46e7e3 Add support for systemd cgroup mount
Systemd uses a named cgroup mount for tracking processes. Add
it as another type of controller, albeit one which we have to
special case in a number of places. In particular we must
never create/delete directories there, nor add tasks. Essentially
the systemd mount is to be considered read-only for libvirt.

With this change both the virCgroupDetectPlacement and
virCgroupCopyPlacement methods must be invoked. The copy
placement method will copy setup for resource controllers
only. The detect placement method will probe for any
named controllers, or resource controllers not already
setup.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-31 19:27:19 +01:00
Eric Blake
a2d0c3f553 build: fix vircgroup build on mingw
The previous patch was incomplete.

  CC       libvirt_util_la-vircgroup.lo
../../src/util/vircgroup.c:70:12: error: 'virCgroupPartitionEscape' declared 'static' but never defined [-Werror=unused-function]
 static int virCgroupPartitionEscape(char **path);
            ^

* src/util/vircgroup.c (virCgroupPartitionEscape): Move forward
declaration inside conditional.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-07-29 08:56:20 -06:00
Daniel P. Berrange
7cf81fa175 Conditionalize build of virCgroupValidateMachineGroup
The virCgroupValidateMachineGroup method calls some functions
which are only conditionally compiled, thus it too must be
made conditional. This fixes the build on non-Linux hosts.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-29 14:36:44 +01:00
Daniel P. Berrange
56b54173ed Skip detecting placement if controller is disabled
If the app has provided a whitelist of controllers to be used,
we skip detecting its mount point. We still, however, fill in
the placement info which later confuses the machine name
validation code. Skip detecting placement if the controller
mount point is not set

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 19:55:51 +01:00
Daniel P. Berrange
5ec5a22493 Add 'controllers' arg to virCgroupNewDetect
When detecting cgroups we must honour any controllers
whitelist the driver may have.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 19:55:47 +01:00
Daniel P. Berrange
c101b851c1 Fix detection of 'emulator' cgroup
When a VM has an 'emulator' child cgroup present, we must
strip off that suffix when detecting the cgroup for a
machine

Rename the virCgroupIsValidMachineGroup method to
virCgroupValidateMachineGroup to make a bit clearer
that this isn't simply a boolean check, it will make
changes to the object.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 19:55:46 +01:00
Daniel P. Berrange
525c9d5a49 Make virCgroupIsValidMachine static
The virCgroupIsValidMachine does not need to be called from
outside the cgroups file now, so make it static.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 19:55:29 +01:00
Daniel P. Berrange
a45b99ead9 Introduce a more convenient virCgroupNewDetectMachine
Instead of requiring drivers to use a combination of calls
to virCgroupNewDetect and virCgroupIsValidMachine, combine
the two into virCgroupNewDetectMachine

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 19:47:30 +01:00
Daniel P. Berrange
3068244e85 Protection against doing bad stuff to the root group
Add protection such that the virCgroupRemove and
virCgroupKill* do not do anything to the root cgroup.

Killing all PIDs in the root cgroup does not end well.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 11:42:48 +01:00
Daniel P. Berrange
b333330aa5 New cgroups API for atomically creating machine cgroups
Instead of requiring one API call to create a cgroup and
another to add a task to it, introduce a new API
virCgroupNewMachine which does both jobs at once. This
will facilitate the later code to talk to systemd to
achieve this job which is also atomic.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-25 11:42:47 +01:00
Roman Bogorodskiy
fa6805e55e Fix virCgroupAvailable() w/o HAVE_GETMNTENT_R defined
virCgroupAvailable() implementation calls getmntent_r
without checking if HAVE_GETMNTENT_R is defined, so it fails
to build on platforms without getmntent_r support.

Make virCgroupAvailable() just return false without
HAVE_GETMNTENT_R.
2013-07-24 15:31:34 +02:00
Daniel P. Berrange
d64e852b5a Remove obsolete cgroups creation apis
The virCgroupNewDomainDriver and virCgroupNewDriver methods
are obsolete now that we can auto-detect existing cgroup
placement. Delete them to reduce code bloat.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-23 22:46:31 +01:00
Daniel P. Berrange
e638778eb3 Add API for checking if a cgroup is valid for a domain
Add virCgroupIsValidMachine API to check whether an auto
detected cgroup is valid for a machine. This lets us
check if a VM has just been placed into some generic
shared cgroup, or worse, the root cgroup

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-23 22:46:31 +01:00
Daniel P. Berrange
66a7f857f3 Add a virCgroupNewDetect API for finding cgroup placement
Add a virCgroupNewDetect API which is used to initialize a
cgroup object with the placement of an arbitrary process.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-23 22:35:26 +01:00
Daniel P. Berrange
0d7f45aea7 Convert remainder of cgroups code to report errors
Convert the remaining methods in vircgroup.c to report errors
instead of returning errno values.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-22 13:09:58 +01:00
Daniel P. Berrange
3260fdfab0 Convert the virCgroupKill* APIs to report errors
Instead of returning errno values, change the virCgroupKill*
APIs to fully report errors.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-22 13:09:58 +01:00
Daniel P. Berrange
b64dabff27 Report full errors from virCgroupNew*
Instead of returning raw errno values, report full libvirt
errors in virCgroupNew* functions.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-22 13:09:58 +01:00
Ján Tomko
cc7329317f cgroup: reuse buffer for getline
Reuse the buffer for getline and track buffer allocation
separately from the string length to prevent unlikely
out-of-bounds memory access.

This fixes the following leak that happened when zero bytes were read:

==404== 120 bytes in 1 blocks are definitely lost in loss record 1,344 of 1,671
==404==    at 0x4C2C71B: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==404==    by 0x906F862: getdelim (iogetdelim.c:68)
==404==    by 0x52A48FB: virCgroupPartitionNeedsEscaping (vircgroup.c:1136)
==404==    by 0x52A0FB4: virCgroupPartitionEscape (vircgroup.c:1171)
==404==    by 0x52A0EA4: virCgroupNewDomainPartition (vircgroup.c:1450)
2013-07-17 14:08:11 +02:00
Daniel P. Berrange
f8b42f3224 Convert 'int i' to 'size_t i' in src/util/ files
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-10 17:40:13 +01:00
Michal Privoznik
a2f8babc7d Adapt to VIR_ALLOC and virAsprintf in src/util/* 2013-07-10 11:07:33 +02:00
Michal Privoznik
8290cbbc38 viralloc: Report OOM error on failure
Similarly to VIR_STRDUP, we want the OOM error to be reported in
VIR_ALLOC and friends.
2013-07-10 11:07:31 +02:00
Michal Privoznik
bc13222185 virCgroupNewPartition: Don't leak @newpath
The @newpath variable is allocated in virCgroupSetPartitionSuffix(). But
it's newer freed.
2013-07-03 09:42:11 +02:00
Ján Tomko
5bc8ecb8d1 Plug leak in virCgroupMoveTask
We only break out of the while loop if *content is an empty string.
However the buffer has been allocated to BUFSIZ + 1 (8193 in my case),
but it gets overwritten in the next for iteration.

Move VIR_FREE right before we overwrite it to avoid the leak.

==5777== 16,386 bytes in 2 blocks are definitely lost in loss record 1,022 of 1,027
==5777==    by 0x5296E28: virReallocN (viralloc.c:184)
==5777==    by 0x52B0C66: virFileReadLimFD (virfile.c:1137)
==5777==    by 0x52B0E1A: virFileReadAll (virfile.c:1199)
==5777==    by 0x529B092: virCgroupGetValueStr (vircgroup.c:534)
==5777==    by 0x529AF64: virCgroupMoveTask (vircgroup.c:1079)

Introduced by 83e4c77.

https://bugzilla.redhat.com/show_bug.cgi?id=978352
2013-06-26 15:38:01 +02:00
Ján Tomko
306c49ffd5 Fix invalid read in virCgroupGetValueStr
Don't check for '\n' at the end of file if zero bytes were read.

Found by valgrind:
==404== Invalid read of size 1
==404==    at 0x529B09F: virCgroupGetValueStr (vircgroup.c:540)
==404==    by 0x529AF64: virCgroupMoveTask (vircgroup.c:1079)
==404==    by 0x1EB475: qemuSetupCgroupForEmulator (qemu_cgroup.c:1061)
==404==    by 0x1D9489: qemuProcessStart (qemu_process.c:3801)
==404==    by 0x18557E: qemuDomainObjStart (qemu_driver.c:5787)
==404==    by 0x190FA4: qemuDomainCreateWithFlags (qemu_driver.c:5839)

Introduced by 0d0b409.

https://bugzilla.redhat.com/show_bug.cgi?id=978356
2013-06-26 15:05:43 +02:00
Ján Tomko
e557766c3b Replace two-state local integers with bool
Found with 'git grep "= 1"'.
2013-06-06 17:22:53 +02:00
Viktor Mihajlovski
eb21408f44 cgroups: Do not enforce nonexistent controllers
Currently, the controllers argument to virCgroupDetect acts both as
a result filter and a required controller specification, which is
a bit overloaded. If both functionalities are needed, it would be
better to have them seperated into a filter and a requirement mask.
The only situation where it is used today is to ensure that only
CPU related controllers are used for the VCPU directories. But here
we clearly do not want to enforce the existence of cpu, cpuacct and
specifically not cpuset at the same time.
This commit changes the semantics of controllers to "filter only".
Should a required mask ever be needed, more work will have to be done.

Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
2013-05-24 12:11:24 +02:00
Michal Privoznik
eb8e5e8774 Adapt to VIR_STRDUP and VIR_STRNDUP in src/util/vircgroup.c
This commit is separate due to unusual paradigm compared to the
most source files.
2013-05-24 10:10:03 +02:00
Michal Privoznik
b43bb98a31 virCgroupAddTaskStrController: s/-1/-ENOMEM/
Within whole vircgroup.c we 'return -errno', e.g. 'return -ENOMEM'.
However, in this specific function virCgroupAddTaskStrController
we weren't returning -ENOMEM but -1 despite fact that later in
the function we are returning one of errno values indeed.
2013-05-24 10:03:22 +02:00
Eric Blake
83e4c77547 cgroup: be robust against cgroup movement races
https://bugzilla.redhat.com/show_bug.cgi?id=965169 documents a
problem starting domains when cgroups are enabled; I was able
to reliably reproduce the race about 5% of the time when I added
hooks to domain startup by 3 seconds (as that seemed to be about
the length of time that qemu created and then closed a temporary
thread, probably related to aio handling of initially opening
a disk image).  The problem has existed since we introduced
virCgroupMoveTask in commit 9102829 (v0.10.0).

There are some inherent TOCTTOU races when moving tasks between
kernel cgroups, precisely because threads can be created or
completed in the window between when we read a thread id from the
source and when we write to the destination.  As the goal of
virCgroupMoveTask is merely to move ALL tasks into the new
cgroup, it is sufficient to iterate until no more threads are
being created in the old group, and ignoring any threads that
die before we can move them.

It would be nicer to start the threads in the right cgroup to
begin with, but by default, all child threads are created in
the same cgroup as their parent, and we don't want vcpu child
threads in the emulator cgroup, so I don't see any good way
of avoiding the move.  It would also be nice if the kernel were
to implement something like rename() as a way to atomically move
a group of threads from one cgroup to another, instead of forcing
a window where we have to read and parse the source, then format
and write back into the destination.

* src/util/vircgroup.c (virCgroupAddTaskStrController): Ignore
ESRCH, because a thread ended between read and write attempts.
(virCgroupMoveTask): Loop until all threads have moved.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-05-21 11:33:56 -06:00
Osier Yang
3fcc1df2f8 src/utils: Remove the whitespace before ";" 2013-05-21 23:41:45 +08:00
Daniel P. Berrange
c2cf5f1c2a Fix failure to detect missing cgroup partitions
Change bbe97ae968 caused the
QEMU driver to ignore ENOENT errors from cgroups, in order
to cope with missing /proc/cgroups. This is not good though
because many other things can cause ENOENT and should not
be ignored. The callers expect to see ENXIO when cgroups
are not present, so adjust the code to report that errno
when /proc/cgroups is missing

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-05-17 10:25:15 +01:00
Jim Fehlig
bbe97ae968 Fix starting domains when kernel has no cgroups support
Found that I was unable to start existing domains after updating
to a kernel with no cgroups support

  # zgrep CGROUP /proc/config.gz
  # CONFIG_CGROUPS is not set
  # virsh start test
  error: Failed to start domain test
  error: Unable to initialize /machine cgroup: Cannot allocate memory

virCgroupPartitionNeedsEscaping() correctly returns errno (ENOENT) when
attempting to open /proc/cgroups on such a system, but it was being
dropped in virCgroupSetPartitionSuffix().

Change virCgroupSetPartitionSuffix() to propagate errors returned by
its callees.  Also check for ENOENT in qemuInitCgroup() when determining
if cgroups support is available.
2013-05-13 09:27:46 -06:00
Daniel P. Berrange
0ced83dcfb Escaping leading '.' in cgroup names
Escaping a leading '.' with '_' in the cgroup names

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-05-13 14:28:46 +01:00
Eric Blake
25ae3d3015 build: avoid useless virAsprintf
virAsprintf(&foo, "%s", bar) is wasteful compared to
foo = strdup(bar) (or eventually, VIR_STRDUP(foo, bar),
but one thing at a time...).

Noticed while reviewing Laine's attempt to clean up broken
qemu:///session.

* cfg.mk (sc_prohibit_asprintf): Enhance rule.
* src/esx/esx_storage_backend_vmfs.c
(esxStorageBackendVMFSVolumeLookupByKey): Fix offender.
* src/network/bridge_driver.c (networkStateInitialize): Likewise.
* src/nwfilter/nwfilter_dhcpsnoop.c (virNWFilterSnoopDHCPOpen):
Likewise.
* src/storage/storage_backend_sheepdog.c
(virStorageBackendSheepdogRefreshVol): Likewise.
* src/util/vircgroup.c (virCgroupAddTaskStrController): Likewise.
* src/util/virdnsmasq.c (addnhostsAdd): Likewise.
* src/xen/block_stats.c (xenLinuxDomainDeviceID): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectOpen): Likewise.
* tools/virsh.c (vshGetTypedParamValue): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-05-02 13:35:26 -06:00
Daniel P. Berrange
f3662737b1 Do proper escaping of cgroup resource partitions
If a user cgroup name begins with "cgroup.", "_" or with any of
the controllers from /proc/cgroups followed by a dot, then they
need to be prefixed with a single underscore. eg if there is
an object "cpu.service", then this would end up as "_cpu.service"
in the cgroup filesystem tree, however, "waldo.service" would
stay "waldo.service", at least as long as nobody comes up with
a cgroup controller called "waldo".

Since we require a '.XXXX' suffix on all partitions, there is
no scope for clashing with the kernel 'tasks' and 'release_agent'
files.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-26 13:52:02 +01:00
Daniel P. Berrange
9ddfe7eea6 Ensure all cgroup partitions have a suffix of ".partition"
If the partition named passed in the XML does not already have
a suffix, ensure it gets a '.partition' added to each component.
The exceptions are /machine, /user and /system which do not need
to have a suffix, since they are fixed partitions at the top
level.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-26 13:52:02 +01:00
Daniel P. Berrange
824e86e723 Change VM cgroup suffix from '{lxc,qemu}.libvirt' to 'libvirt-{lxc,qemu}'
Recently we changed to create VM cgroups with the naming pattern
$VMNAME.$DRIVER.libvirt. Following discussions with the systemd
community it was decided that only having a single '.' in the
names is preferrable. So this changes the naming scheme to be
$VMNAME.libvirt-$DRIVER. eg for LXC 'mycontainer.libvirt-lxc' or
for KVM 'myvm.libvirt-qemu'.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-26 13:52:02 +01:00
Eric Blake
1fbf190554 build: avoid unsafe functions in libgen.h
POSIX says that both basename() and dirname() may return static
storage (aka they need not be thread-safe); and that they may but
not must modify their input argument.  Furthermore, <libgen.h>
is not available on all platforms.  For these reasons, you should
never use these functions in a multi-threaded library.

Gnulib instead recommends a way to avoid the portability nightmare:
gnulib's "dirname.h" provides useful thread-safe counterparts.  The
obvious dir_name() and base_name() are GPL (because they malloc(),
but call exit() on failure) so we can't use them; but the LGPL
variants mdir_name() (malloc's or returns NULL) and last_component
(always points into the incoming string without modifying it,
differing from basename semantics only on corner cases like the
empty string that we shouldn't be hitting in the first place) are
already in use in libvirt.  This finishes the swap over to the safe
functions.

* cfg.mk (sc_prohibit_libgen): New rule.
* src/util/vircgroup.c: Fix offenders.
* src/parallels/parallels_storage.c (parallelsPoolAddByDomain):
Likewise.
* src/parallels/parallels_network.c (parallelsGetBridgedNetInfo):
Likewise.
* src/node_device/node_device_udev.c (udevProcessSCSIHost)
(udevProcessSCSIDevice): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskDeleteVol): Likewise.
* src/util/virpci.c (virPCIGetDeviceAddressFromSysfsLink):
Likewise.
* src/util/virstoragefile.h (_virStorageFileMetadata): Avoid false
positive.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-04-25 14:47:01 -06:00
Stefan Berger
0cb171f60f Fix compilation error in util/vircgroup.c
Fix the error

util/vircgroup.c: In function 'virCgroupNewDomainPartition':
util/vircgroup.c:1299:11: error: declaration of 'dirname' shadows a global declaration [-Werror=shadow]


Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
2013-04-16 08:16:37 -04:00
Daniel P. Berrange
e7d8ab016b Add support for perf_event and net_cls cgroup controllers
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:32 +01:00
Daniel P. Berrange
1da631ecf3 Add an API for re-mounting cgroups, to isolate the process location
Add a virCgroupIsolateMount method which looks at where the
current process is place in the cgroups (eg /system/demo.lxc.libvirt)
and then remounts the cgroups such that this sub-directory
becomes the root directory from the current process' POV.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:32 +01:00
Daniel P. Berrange
83336118db Track symlinks for co-mounted cgroup controllers
If a cgroup controller is co-mounted with another, eg

   /sys/fs/cgroup/cpu,cpuacct

Then it is a requirement that there exist symlinks at

   /sys/fs/cgroup/cpu
   /sys/fs/cgroup/cpuacct

pointing to the real mount point. Add support to virCgroupPtr
to detect and track these symlinks

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:32 +01:00
Daniel P. Berrange
767596bdb4 Remove non-functional code for setting up non-root cgroups
The virCgroupNewDriver method had a 'bool privileged' param.
If a false value was ever passed in, it would simply not
work, since non-root users don't have any privileges to create
new cgroups. Just delete this broken code entirely and make
the QEMU driver skip cgroup setup in non-privileged mode

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
aa8604dd45 Add a new virCgroupNewPartition for setting up resource partitions
A resource partition is an absolute cgroup path, ignoring the
current process placement. Expose a virCgroupNewPartition API
for constructing such cgroups

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
109554d714 Cleanup if creating cgroup directories fails
Currently if virCgroupMakeGroup fails, we can get in a situation
where some controllers have been setup, but others not. Ensure
we call virCgroupRemove to remove what we've done upon failure

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
854a004fd6 Add misc extra debugging into cgroups code
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
8d1c141a8d Refactor cgroups internal data structures
Currently the virCgroupPtr struct contains 3 pieces of
information

 - path - path of the cgroup, relative to current process'
   cgroup placement
 - placement - current process' placement in each controller
 - mounts - mount point of each controller

When reading/writing cgroup settings, the path & placement
strings are combined to form the file path. This approach
only works if we assume all cgroups will be relative to
the current process' cgroup placement.

To allow support for managing cgroups at any place in the
heirarchy a change is needed. The 'placement' data should
reflect the absolute path to the cgroup, and the 'path'
value should no longer be used to form the paths to the
cgroup attribute files.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
04c18d25f1 Rename virCgroupForXXX to virCgroupNewXXX
Rename all the virCgroupForXXX methods to use the form
virCgroupNewXXX since they are all constructors. Also
make sure the output parameter is the last one in the
list, and annotate all pointers as non-null. Fix up
all callers, and make sure they use true/false not 0/1
for the boolean parameters

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
f0e5f92434 Pull definition of structs out of vircgroup.c to vircgrouppriv.h
The definition of structs for cgroups are kept in vircgroup.c since
they are intended to be private from users of the API. To enable
effective testing, however, they need to be accessible. To address
the latter issue, without compronmising the former, this introduces
a new vircgrouppriv.h file to hold the struct definitions.

To prevent other files including this private header, it requires
that __VIR_CGROUP_ALLOW_INCLUDE_PRIV_H__ be defined before inclusion

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
c9b8cdfec1 Add missing param to virCgroupForDriver stub
The virCgroupForDriver method recently gained an 'int controllers'
parameter, but the stub impl did not

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-15 17:35:31 +01:00
Daniel P. Berrange
dca927c82f Rename virCgroupMounted to virCgroupHasController & make it more robust
The virCgroupMounted method is badly named, since a controller can be
mounted, but disabled in the current object. Rename the method to be
virCgroupHasController. Also make it tolerant to a  NULL virCgroupPtr
and out-of-range controller index, to avoid duplication of these
checks in all callers

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-08 14:49:12 +01:00
Daniel P. Berrange
56f27b3bbc Don't create dirs in cgroup controllers we don't want to use
Currently when getting an instance of virCgroupPtr we will
create the path in all cgroup controllers. Only at the virt
driver layer are we attempting to filter controllers. This
is bad because the mere act of creating the dirs in the
controllers can have a functional impact on the kernel,
particularly for performance.

Update the virCgroupForDriver() method to accept a bitmask
of controllers to use. Only create dirs in the controllers
that are requested. When creating cgroups for domains,
respect the active controller list from the parent cgroup

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-05 10:41:54 +01:00
Daniel P. Berrange
804a809a06 Rename virCgroupGetAppRoot to virCgroupForSelf
The virCgroupGetAppRoot is not clear in its meaning. Change
to virCgroupForSelf to highlight that this returns the
cgroup config for the caller's process

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-05 10:41:54 +01:00
Gao feng
8d19a9f578 cgroup: export virCgroupRemoveRecursively
We will use virCgroupRemoveRecursively to remove cgroup
directories in the coming patch.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2013-03-20 14:21:27 -06:00
Daniel P. Berrange
279336c5d8 Avoid spamming logs with cgroups warnings
The code for putting the emulator threads in a separate cgroup
would spam the logs with warnings

2013-02-27 16:08:26.731+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 3
2013-02-27 16:08:26.731+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 4
2013-02-27 16:08:26.732+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 6

This is because it has only created child cgroups for 3 of the
controllers, but was trying to move the processes from all the
controllers. The fix is to only try to move threads in the
controllers we actually created. Also remove the warning and
make it return a hard error to avoid such lazy callers in the
future.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-02-27 22:51:24 +00:00
Daniel P. Berrange
44f6ae27fe Rename util.{c,h} to virutil.{c,h} 2012-12-21 11:19:49 +00:00
Daniel P. Berrange
ab9b7ec2f6 Rename memory.{c,h} to viralloc.{c,h} 2012-12-21 11:17:14 +00:00
Daniel P. Berrange
936d95d347 Rename logging.{c,h} to virlog.{c,h} 2012-12-21 11:17:14 +00:00
Daniel P. Berrange
f9c7020c1f Rename cgroup.{h,c} to vircgroup.{h,c}
To bring in line with new naming practice, rename the=
src/util/cgroup.{h,c} files to vircgroup.{h,c}

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-12-21 11:17:12 +00:00