The individual hypervisor drivers were directly referencing
APIs in src/nodeinfo.c in their virDriverPtr struct. Separate
these methods, so there is always a wrapper in the hypervisor
driver. This allows the unused virConnectPtr args to be
removed from the nodeinfo.c file. Again this will ensure that
ACL checks will only be performed on invocations that are
directly associated with public API usage.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
If libnuma is not compiled in, or numa_available() returns an
error, stub out fake NUMA info consisting of one NUMA cell
containing all CPUs and memory.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Not all kernel builds have any entries under the location
/sys/devices/system/cpu/cpu0/topology. We already cope with
that being missing in some cases, but not all. Update the
code which looks for thread_siblings to cope with the missing
file
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
'virsh capabilities' will now include a new <memory> element
per <cell> of the topology, as in:
<topology>
<cells num='2'>
<cell id='0'>
<memory unit='KiB'>12572412</memory>
<cpus num='12'>
...
</cell>
Signed-off-by: Eric Blake <eblake@redhat.com>
When linuxNodeInfoCPUPopulate() method triggered use of an
uninitialize value, since it did not initialize the 'sockets'
field in the virNodeInfoPtr struct:
==30020== Conditional jump or move depends on uninitialised value(s)
==30020== at 0x5125DBD: linuxNodeInfoCPUPopulate (nodeinfo.c:513)
==30020== by 0x51261A0: nodeGetInfo (nodeinfo.c:884)
==30020== by 0x149B9B10: qemuCapsInit (qemu_capabilities.c:846)
==30020== by 0x14A11B25: qemuCreateCapabilities (qemu_driver.c:424)
==30020== by 0x14A12426: qemuStartup (qemu_driver.c:874)
==30020== by 0x512A7AF: virStateInitialize (libvirt.c:822)
==30020== by 0x40DE04: daemonRunStateInit (libvirtd.c:877)
==30020== by 0x50ADCE5: virThreadHelper (virthreadpthread.c:161)
==30020== by 0x328CA07D14: start_thread (pthread_create.c:308)
==30020== by 0x328C6F246C: clone (clone.S:114)
(happened twice)
if (socks > nodeinfo->sockets) <--- here
nodeinfo->sockets = socks;
Rather than doing this for each field, just make the caller memset
the entire struct to zero.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This patch adds data gathering to the NUMA gathering files and adds
support for outputting the data. The test driver and xend driver need to
be adapted to fill sensible data to the structure in a future patch.
This will allow storing additional topology data in the NUMA topology
definition.
This patch changes the storage type and fixes fallout of the change
across the drivers using it.
This patch also changes semantics of adding new NUMA cell information.
Until now the data were re-allocated and copied to the topology
definition. This patch changes the addition function to steal the
pointer to a pre-allocated structure to simplify the code.
The use of switch statements inside a bounded for loop resulted in some
false positives regarding the "default:" label which cannot be reached
since each of the other case statements use the possible for loop values.
A [dead_error_begin] was added before the default label.
Commit id ebdbe25a adjusted the algorithm and the caller guarantees that
the 'params' will have a '_' in the name being searched. Add the [returned_null]
tag to the two instances.
Replace use of uname in nodeGetInfo with virArch APIs to
provide canonicalization of host architecture name
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It makes no sense to fail the whole getting command if there is
a parameter unsupported by the kernel. This patch fixes it by
omitting the unsupported parameter for getMemoryParameters.
And for setMemoryParameters, this checks if there is an unsupported
parameter up front of the setting, and just returns failure if not
all parameters are supported.
Prior to this patch, 'virsh nodecpumap' on older kernels reported:
error: Unable to get cpu map
error: out of memory
* src/nodeinfo.c (linuxParseCPUmax): Don't overwrite error.
(nodeGetCPUBitmap): Provide backup implementation.
On RHEL 5, I was getting a segfault trying to start libvirtd,
because we were failing virNodeParseSocket but not checking
for errors, and then calling CPU_SET(-1, &sock_map) as a result.
But if you don't have a topology/physical_package_id file,
then you can just assume that the cpu belongs to socket 0.
* src/nodeinfo.c (virNodeGetCpuValue): Change bool into
default_value.
(virNodeParseSocket): Allow for default value when file is missing,
different from fatal error on reading file.
(virNodeParseNode): Update call sites to fail on error.
Since /sys/devices/system/cpu/present is not available on
older kernels like on RHEL 5.x nodeGetCPUCount will
fail there. The fallback implemented is to scan for
/sys/devices/system/cpu/cpuNN entries.
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Lately there were a few reports of the output of the virsh nodeinfo
command being inaccurate. This patch tries to avoid that by checking if
the topology actually makes sense. If it doesn't we then report a
synthetic topology that indicates to the user that the host capabilities
should be checked for the actual topology.
The libvirt coding standard is to use 'function(...args...)'
instead of 'function (...args...)'. A non-trivial number of
places did not follow this rule and are fixed in this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It turns out that calling virNodeGetCPUMap(conn, NULL, NULL, 0)
is both useful, and with Viktor's patches, common enough to
optimize. Since this interface hasn't been released yet, we
can change the RPC call.
A bit more background on the optimization - learning the cpu count
is a single file read (/sys/devices/system/cpu/possible), but
learning the number of online cpus can possibly trigger a file
read per cpu, depending on the age of the kernel, and all wasted
if the caller passed NULL for both arguments.
* src/nodeinfo.c (nodeGetCPUMap): Avoid bitmap when not needed.
* src/remote/remote_protocol.x (remote_node_get_cpu_map_args):
Supply two separate flags for needed arguments.
* src/remote/remote_driver.c (remoteNodeGetCPUMap): Update
caller.
* daemon/remote.c (remoteDispatchNodeGetCPUMap): Likewise.
* src/remote_protocol-structs: Regenerate.
Ever since commit eefb881, ATTRIBUTE_NONNULL has normally been a
no-op under gcc (since it tends to cause more bugs than it cures
given gcc's current lame implementation of the attribute). However,
the macro is still useful to Coverity and other static-analysis
tools, but only if we use it correctly. Coverity follows gcc's lead
in accepting function declarations with attributes at the end, but
function bodies must attach attributes to the return type. That is,
these are valid:
void foo(void *arg) ATTRIBUTE_NONNULL(1);
void ATTRIBUTE_NONNULL(1) foo(void *arg);
void ATTRIBUTE_NONNULL(1) foo(void *arg) {}
but this is not:
void foo(void *arg) ATTRIBUTE_NONNULL(1) {}
even though you don't get a compile failure until you do static
analysis. Bug introduced in commit 80533ca, with these symptoms:
nodeinfo.c:206: error: expected ',' or ';' before '{' token
cc1: warning: unrecognized command line option "-Wno-suggest-attribute=const"
cc1: warning: unrecognized command line option "-Wno-suggest-attribute=pure"
make[3]: *** [libvirt_driver_la-nodeinfo.lo] Error 1
* src/nodeinfo.c (virNodeParseNode): Fix syntax error when
non-null attribute is in use.
It turns out that the cpuacct results properly account for offline
cpus, and always returns results for every possible cpu, not just
the online ones. So there is no need to check the map of online
cpus in the first place, merely only a need to know the maximum
possible cpu. Meanwhile, virNodeGetCPUBitmap had a subtle change
from returning the maximum id to instead returning the width of
the bitmap (one larger than the maximum id) in commit 2f4c5338,
which made this code encounter some off-by-one logic leading to
bad error messages when a cpu was offline:
$ virsh cpu-stats dom
error: Failed to virDomainGetCPUStats()
error: An error occurred, but the cause is unknown
Cleaning this up unraveled a chain of other unused variables.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Drop
pointless check for cpumap changes, and use correct number of
cpus. Simplify signature.
(qemuDomainGetCPUStats): Adjust caller.
* src/nodeinfo.h (nodeGetCPUCount): New prototype.
(nodeGetCPUBitmap): Drop unused parameter.
* src/nodeinfo.c (nodeGetCPUBitmap): Likewise.
(nodeGetCPUMap): Adjust caller.
(nodeGetCPUCount): New function.
* src/libvirt_private.syms (nodeinfo.h): Export it.
Added an implemention of virNodeGetCPUMap to nodeinfo.c,
(nodeGetCPUMap) which can be used by all drivers for a Linux
hypervisor host.
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Callers should not need to know what the name of the file to
be read in the Linux-specific version of nodeGetCPUmap;
furthermore, qemu cares about online cpus, not present cpus,
when determining which cpus to skip.
While at it, I fixed the fact that we were computing the maximum
online cpu id by doing a slow iteration, when what we really want
to know is the max available cpu.
* src/nodeinfo.h (nodeGetCPUmap): Rename...
(nodeGetCPUBitmap): ...and simplify signature.
* src/nodeinfo.c (linuxParseCPUmax): New function.
(linuxParseCPUmap): Simplify and alter signature.
(nodeGetCPUBitmap): Change implementation.
* src/libvirt_private.syms (nodeinfo.h): Reflect rename.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Update
caller.
Upstream kernel introduced new sysfs knob "merge_across_nodes" to
specify if pages from different numa nodes can be merged. When set
to 0, only pages which physically reside in the memory area of
same NUMA node can be merged. When set to 1, pages from all nodes
can be merged.
This patch supports the tuning by adding new param field
"shm_merge_across_nodes".
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
Commit aaa8ab3 added new static functions that are only used on Linux;
but commit 22acfdc didn't go far enough to fix compiler issues.
* src/nodeinfo.c (nodeSetMemoryParameterValue)
(nodeGetMemoryParameterValue): Conditionally compile based on use.
Only implemented for linux platform.
* src/nodeinfo.h: (Declare node{Get,Set}MemoryParameters)
* src/nodeinfo.c: (Implement node{Get,Set}MemoryParameters)
* src/libvirt_private.syms: (Export those two new internal APIs to
private symbols)
Building on RHEL 5 warned:
nodeinfo.c: 305: warning: implicit declaration of function 'CPU_COUNT'
This extension macro in <sched.h> was not added until later glibc.
* src/nodeinfo.c (CPU_COUNT): Add fallback implementation.
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
Update the nodeinfo helper code to use virReportError instead
of the nodeReportError custom macro
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit 80533ca forgot to think about offline cpus. When a node
cpu is offline, then its topology/ subdirectory is not present,
leading to spurious error messages leaked to the user such as:
libvir: error : cannot open /home/dummy/libvirt/tests/nodeinfodata/linux-nodeinfo-sysfs-test-6/node/node0/cpu7/topology/physical_package_id: No such file or directory
Fix that, as well as test it; the test data is gathered from a
machine with one NUMA node, hyperthreading, and with 2 of the
8 cpus offline.
* src/nodeinfo.c (virNodeParseNode): Don't parse topology of
offline cpus.
* tests/nodeinfotest.c (mymain): Run new test.
* tests/nodeinfodata/linux-nodeinfo-sysfs-test-6*: New data.
This patch changes the way data to fill the nodeinfo structure are
gathered. We've gathere the test data by iterating processors an sockets
separately from nodes. The reported data was based solely on information
about core id. Problems arise when eg cores in mulit-processor machines
don't have same id's on both processors or maybe one physical processor
contains more NUMA nodes.
This patch changes the approach how we detect processors and nodes. Now
we start at enumerating nodes and for each node processors, sockets and
threads are enumerated separately. This approach provides acurate data
that comply to docs about the nodeinfo structure. This also enables to
get rid of hacks: see commits 10d9038b74,
ac9dd4a676. (Those changes in nodeinfo.c
are efectively reverted by this patch).
This patch also changes output of one of the tests, as the processor
topology is now acquired more precisely.
For the s390x architecture the sysfs core_id alone is not unique. As a
result it can happen that libvirt thinks there are less host CPUs available
than really present.
Currently, a logical CPU is equivalent to a core for s390x. We therefore
produce a fake core id from the CPU number.
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Minimal CPU "parser" for s390 to avoid compile time warning.
Signed-off-by: Thang Pham <thang.pham@us.ibm.com>
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
To ensure consistent error reporting of invalid arguments,
provide a number of predefined helper methods & macros.
- An arg which must not be NULL:
virCheckNonNullArgReturn(argname, retvalue)
virCheckNonNullArgGoto(argname, label)
- An arg which must be NULL
virCheckNullArgGoto(argname, label)
- An arg which must be positive (ie 1 or greater)
virCheckPositiveArgGoto(argname, label)
- An arg which must not be 0
virCheckNonZeroArgGoto(argname, label)
- An arg which must be zero
virCheckZeroArgGoto(argname, label)
- An arg which must not be negative (ie 0 or greater)
virCheckNonNegativeArgGoto(argname, label)
* src/libvirt.c, src/libvirt-qemu.c,
src/nodeinfo.c, src/datatypes.c: Update to use
virCheckXXXX macros
* po/POTFILES.in: Add libvirt-qemu.c and virterror_internal.h
* src/internal.h: Define macros for checking invalid args
* src/util/virterror_internal.h: Define macros for reporting
invalid args
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
"Instead of developing one CPU with 12 cores, the Magny Cours is
actually two 6 core “Bulldozer” CPUs combined in to one package"
I.e, each package has two NUMA nodes, and the two numa nodes share
the same core ID set (0-6), which means parsing the cores number
from sysfs doesn't work in this case.
And the wrong CPU number could cause three problems for libvirt:
1) performance lost
A domain without "cpuset" or "placement='auto'" (to drive numad)
specified will be only pinned to part of the CPUs.
2) domain can be started
If a domain uses numad, and the advisory nodeset returned from
numad contains node which exceeds the range of wrong total CPU
number. The domain will fail to start, as the bitmask passed to
sched_setaffinity could be fully filled with zero.
3) wrong CPU number affects lots of stuffs.
E.g. for command "virsh vcpuinfo", "virsh vcpupin", it will always
output with the truncated CPU list.
For more details:
https://www.redhat.com/archives/libvir-list/2012-May/msg00607.html
This patch is to fix the problem by parsing /proc/cpuinfo to get
the value of field "cpu cores", and use it as nodeinfo->cores if
it's greater than the cores number from sysfs.
We had previously weakened our nodeinfotest in order to ignore parsed
node values, because the parse function was mistakenly relying on
host files. A better fix is to avoid using the numactl library, but
to instead parse the same files that numactl would read, all while
allowing the files to be relative to our choice of directory.
* src/nodeinfo.c (CPU_SYS_PATH, NODE_SYS_PATH): Replace with...
(SYSFS_SYSTEM_PATH): ...parent directory.
(linuxNodeInfoCPUPopulate): Check NUMA nodes from requested
directory (by inlining numactl code).
(nodeGetCPUmap, nodeGetMemoryStats): Adjust macro use.
* tests/nodeinfotest.c (linuxTestCompareFiles, linuxTestNodeInfo):
Update test to match.
We were wasting time to malloc a copy of a constant string, then
copy it into static storage, for every call to nodeGetInfo. At
least we were lucky that it was a constant source, and thus not
subject to even worse issues with one thread clobbering the static
storage while another was using it. This gets rid of the waste,
by passing the string through the stack instead, as well as renaming
internal functions to better match our conventions.
* src/nodeinfo.c (sysfs_path): Delete.
(get_cpu_value, count_thread_siblings, parse_socket): Add
parameter, and rename...
(virNodeGetCpuValue, virNodeCountThreadSiblings)
(virNodeParseSocket): ... into a common namespace.
(cpu_online, parse_core): Inline into callers.
(linuxNodeInfoCPUPopulate): Update caller.
(nodeGetInfo): Drop a useless malloc.
Error: RESOURCE_LEAK:
/builddir/build/BUILD/libvirt-0.9.10/src/nodeinfo.c:629: alloc_fn: Calling allocation function "fopen".
/builddir/build/BUILD/libvirt-0.9.10/src/nodeinfo.c:629: var_assign: Assigning: "cpuinfo" = storage returned from "fopen("/proc/cpuinfo", "r")".
/builddir/build/BUILD/libvirt-0.9.10/src/nodeinfo.c:638: leaked_storage: Variable "cpuinfo" going out of scope leaks the storage it points to.
I noticed these compiler warnings when building for the s390 architecture.
* src/node_device/node_device_udev.c (udevDeviceMonitorStartup):
Mark unused variable.
* src/nodeinfo.c (linuxNodeInfoCPUPopulate): Avoid unused variable.
The code is splattered with a mix of
sizeof foo
sizeof (foo)
sizeof(foo)
Standardize on sizeof(foo) and add a syntax check rule to
enforce it
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The blocks to extract node information on a per-arch
basis wasn't well balanced leading to a compilation
failure if not on one of the handled arches (PCs and PPCs)
Fix memory leak:
==27534== 24 bytes in 1 blocks are definitely lost in loss record 207 of 530
==27534== at 0x4A05E46: malloc (vg_replace_malloc.c:195)
==27534== by 0x38EC26EC37: vasprintf (in /lib64/libc-2.13.so)
==27534== by 0x4E998E6: virVasprintf (util.c:1677)
==27534== by 0x4E999F1: virAsprintf (util.c:1695)
==27534== by 0x4F1EAAC: nodeGetInfo (nodeinfo.c:593)
==27534== by 0x47948F: qemuCapsInitCPU (qemu_capabilities.c:855)
==27534== by 0x4796B1: qemuCapsInit (qemu_capabilities.c:915)
==27534== by 0x456550: qemuCreateCapabilities (qemu_driver.c:245)
==27534== by 0x4578C4: qemudStartup (qemu_driver.c:580)
==27534== by 0x4F20886: virStateInitialize (libvirt.c:852)
==27534== by 0x420E55: daemonRunStateInit (libvirtd.c:1156)
==27534== by 0x4E94C56: virThreadHelper (threads-pthread.c:157)
Mark this leaked variable as const char * when it is passed into another
function.
/proc/cpuinfo
Libvirt at present depends on /proc/cpuinfo to gather host
details such as CPUs, cores, threads, etc. This is an architecture-
dependent approach. An alternative is to use 'Sysfs', which provides
a platform-agnostic interface to parse host CPU topology.
Signed-off-by: Prerna Saxena <prerna@linux.vnet.ibm.com>
Introduced by 5e495c8b, except the ones for checking if numa
is supported by host, all the NO_SUPPORT are changed back. For
the ones about numa checking, change them into INTERNAL_ERROR.
When building libvirt without libvirtd, we will receive the following error
message:
make[3]: Entering directory `/home/wency/rpmbuild/BUILD/libvirt-0.9.2/tools'
CC virsh-virsh.o
CC virsh-console.o
GEN virt-xml-validate
GEN virt-pki-validate
CCLD virsh
./src/.libs/libvirt.so: undefined reference to `numa_available'
./src/.libs/libvirt.so: undefined reference to `numa_max_node'
collect2: ld returned 1 exit status
The reason is that: we check numactl only when building qemu driver, and qemu
driver will not be built when bulding without libvirtd. So with_numactl's
value is check and we will not link libnuma.so.
In the other function, we call numa_available() and numa_max_node() only
when HAVE_NUMACTL is 1. We should do the same check in the function nodeGetMemoryStats().
Detected by autobuild.sh when cross-building for mingw.
Introduced in commits ce76e85 and af35cec.
* src/nodeinfo.c (nodeGetCPUStats, nodeGetMemoryStats): Mark
parameters as potentially unused.
Up to now we missed parser for cpuinfo on x390(x) machines. Those machines
have only 1 thread, core, socket. What is missing is information about
CPU frequency.
Due to differences in /proc/cpuinfo the parsing of the cpu data is
different between architectures. On PPC /proc/cpuinfo looks like this:
[original formatting with tabs]
processor : 0
cpu : PPC970MP, altivec supported
clock : 2297.700000MHz
revision : 1.1 (pvr 0044 0101)
processor : 1
cpu : PPC970MP, altivec supported
clock : 2297.700000MHz
revision : 1.1 (pvr 0044 0101)
[..]
timebase : 14318000
platform : pSeries
model : IBM,8844-AC1
machine : CHRP IBM,8844-AC1
The patch adapts the parsing of the data found in /proc/cpuinfo.
/sys/devices/system/cpu/cpuX/topology/physical_package_id also
always returns -1. Check for it on ppc and make it '0' if found negative.
Virsh freecell --all was not only getting wrong NUMA nodes count, but
even the NUMA nodes IDs. They doesn't have to be continuous, as I've
found out during testing this. Therefore a modification of
nodeGetCellsFreeMemory() error message.
When running 'make check' under a multi-cpu Dom0 xen machine,
nodeinfotest had a spurious failure it was reading from
/sys/devices/system/cpu, but xen has no notion of topology. The test
was intended to be isolated from reading any real system files; the
regression was introduced in Mar 2010 with commit aa2f6f96dd.
Fix things by allowing an early exit for the testsuite.
* src/nodeinfo.c (linuxNodeInfoCPUPopulate): Add parameter.
(nodeGetInfo): Adjust caller.
* tests/nodeinfotest.c (linuxTestCompareFiles): Likewise.
The nodeinfo structure includes
nodes : the number of NUMA cell, 1 for uniform mem access
sockets : number of CPU socket per node
cores : number of core per socket
threads : number of threads per core
which does not work well for NUMA topologies where each node does not
consist of integral number of CPU sockets.
We also have VIR_NODEINFO_MAXCPUS macro in public libvirt.h which
computes maximum number of CPUs as (nodes * sockets * cores * threads).
As a result, we can't just change sockets to report total number of
sockets instead of sockets per node. This would probably be the easiest
since I doubt anyone is using the field directly. But because of the
macro, some apps might be using sockets indirectly.
This patch leaves sockets to be the number of CPU sockets per node (and
fixes qemu driver to comply with this) on machines where sockets can be
divided by nodes. If we can't divide sockets by nodes, we behave as if
there was just one NUMA node containing all sockets. Apps interested in
NUMA should consult capabilities XML, which is what they probably do
anyway.
This way, the only case in which apps that care about NUMA may break is
on machines with funky NUMA topology. And there is a chance libvirt
wasn't able to start any guests on those machines anyway (although it
depends on the topology, total number of CPUs and kernel version).
Nothing changes at all for apps that don't care about NUMA.
Similarly to deprecating close(), I am now deprecating fclose() and
introduce VIR_FORCE_FCLOSE() and VIR_FCLOSE(). Also, fdopen() is replaced with
VIR_FDOPEN().
Most of the files are opened in read-only mode, so usage of
VIR_FORCE_CLOSE() seemed appropriate. Others that are opened in write
mode already had the fclose()< 0 check and I converted those to
VIR_FCLOSE()< 0.
I did not find occurrences of possible double-closed files on the way.
When finding a sparse NUMA topology, libnuma will return ENOENT
the first time it is invoked. On subsequent invocations it
will return success, but with an all-1's CPU mask. Check for
this, to avoid polluting the capabilities XML with 4096 bogus
CPUs
* src/nodeinfo.c: Check for all-1s CPU mask
https://bugzilla.redhat.com/622515 - When hot-unplugging CPUs,
libvirt failed to start a guest that had been pinned to CPUs that
were still online.
Tested on a dual-core laptop, where I also discovered that, per
http://www.cyberciti.biz/files/linux-kernel/Documentation/cpu-hotplug.txt,
/sys/devices/system/cpu/cpu0/online does not exist on systems where it
cannot be hot-unplugged.
* src/nodeinfo.c (linuxNodeInfoCPUPopulate): Ignore CPUs that are
currently offline. Detect readdir failure.
(parse_socket): Move guts...
(get_cpu_value): ...to new function, shared with...
(cpu_online): New function.
The nodeGetInfo code was always assuming that machine had a
single NUMA node, which is not correct. The good news is that
libnuma gives us this information pretty easily, so let's
properly report it.
NOTE: With recent hardware starting to support CPU hot-add
and hot-remove, both this code and the nodeCapsInitNUMA()
code are quickly going to become obsolete. We'll have to
think of a more dynamic solution for dealing with NUMA
nodes and CPUs that can come and go at will.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
As pointed out by eblake, I made a real hash of the
nodeinfo code with commit
aa2f6f96dd. This patch
cleans it up:
1) Do more work at compile time instead of runtime (minor)
2) Properly handle the hex digits that come from
/sys/devices/system/cpu/cpu*/topology/thread_siblings
3) Fix up some error paths that could cause SEGV
4) Used unsigned's for the cpu numbers (cpu -1 doesn't
make any sense)
Along with the recent patch from jdenemar to zero out
the nodeinfo structure, I've re-tested this on the
machines having the problems, and it seems to be good.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
The nodeinfo structure wasn't initialized in qemu driver and with the
recent change in CPU topology parsing, old value of nodeinfo->sockets
could be used and incremented giving totally bogus results.
Let's just wipe the structure completely.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The current code for "nodeinfo" is pretty naive
about socket and thread information. To determine the
sockets, it just takes the number of cpus and divides
by the number of cores. For the thread count, it always
sets it to 1. With more recent Intel machines, however,
hyperthreading is again an option, meaning that these
heuristics no longer work and give bogus numbers. This
patch goes through /sys to get the additional
information so we properly report it.
Note that I had to edit the tests not to report on
socket and thread counts, since these are determined
dynamically now.
v2: As pointed out by Eric Blake, gnulib provides
count-one-bits (which is LGPLv2+). Use it instead
of a hand-coded popcnt.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
Add the virStrncpy function, which takes a dst string, source string,
the number of bytes to copy and the number of bytes available in the
dest string. If the source string is too large to fit into the
destination string, including the \0 byte, then no data is copied and
the function returns NULL. Otherwise, this function copies n bytes
from source into dst, including the \0, and returns a pointer to the
dst string. This function is intended to replace all unsafe uses
of strncpy in the code base, since strncpy does *not* guarantee that
the buffer terminates with a \0.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
by running this command:
git ls-files -z | xargs -0 perl -pi -0777 -e 's/\n\n+$/\n/'
This is in preparation for a more strict make syntax-check
rule that will detect trailing blank lines.
