Since kernel version 4.7, processor frequency information is available
on S390. Let's adjust the parser so this information shows up for virsh
nodeinfo:

    # virsh nodeinfo
    CPU model:           s390x
    CPU(s):              8
    CPU frequency:       5000 MHz
    CPU socket(s):       1
    Core(s) per socket:  8
    Thread(s) per core:  1
    NUMA cell(s):        1
    Memory size:         16273908 KiB
Reviewed-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Signed-off-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

Some ARM platforms, such as the original Raspberry Pi, report the
CPU frequency in the BogoMIPS field of /proc/cpuinfo, so libvirt
parsed that field and returned it through its API.

However, not only many more boards don't report any value there,
but several - including ARMv8-based server hardware, and even the
more recent Raspberry Pi 3 - use this field as originally intended:
to report the BogoMIPS value instead of the CPU frequency.

Since we have no way of detecting how the field is being used,
it's better to report no information at all rather than something
ludicrous like "your shiny 96-core aarch64 virtualization host's
CPUs are running at a whopping 100 MHz".

Partially-resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1206353Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Make the parser both more strict, by not ignoring errors reported
by virStrToLong_ui(), and more permissive, by not failing due to
unrelated fields which just happen to have a know prefix and
accepting any amount of whitespace before the numeric value.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

Instead of a generic "your architecture", print the actual
architecture name.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

All different architectures use the same copy-pasted code to parse
processor frequency information from /proc/cpuinfo. Let's extract that
code into a function to avoid repetition.

We now also tolerate if the parsing of /proc/cpuinfo is not successful
and just report a warning instead of bailing out and abandoning the rest
of the CPU information.
Reviewed-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

This new API reads host's CPU microcode version from /proc/cpuinfo.

Unfortunately, there is no other way of reading microcode version which
would be usable from both system and session daemon.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Callers expect the return value to be the total number of vcpus in the
host (including offline vcpus). The refactor in c67e04e2
broke this assumption by using virHostCPUGetOnlineBitmap which only
creates a bitmap long enough to hold the last online vcpu.

Report the full number of host vcpus by returning value from
virHostCPUGetCount().
Signed-off-by: NNitesh Konkar <nitkon12@linux.vnet.ibm.com>
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

The code is already prepared to handle the non-existence of it.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

It is no longer needed thanks to the great virfilewrapper.c.  And this
way we don't have to add a new set of functions for each prefixed
path.

While on that, add two functions that weren't there before, string and
scaled integer reading ones.  Also increase the length of the string
being read by one to accompany for the optional newline at the
end (i.e. change INT_STRLEN_BOUND to INT_BUFSIZE_BOUND).
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

We prefer c89 style of comments.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

And use it in virFileRead*
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Previously, this function must've been called only on Linux in order
to fail gracefully.  That lead to #ifdef mess in callers, so the
function was redesigned so it failed gracefully on non-existing
files.  However that commit forgot to define the function outside the
__linux__ ifdef, it broke non-Linux builds.

Caused by c67e04e2.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

While on that, drop support for kernels from RHEL-5 era (missing
cpu/present file).  Also add some useful functions and export them.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

The functions to retrieve online and present host CPU information
are only supported on Linux for the time being.

This leads to runtime errors if these function are used on other
platforms. To avoid that, code in higher levels using the functions
must replicate the conditional compilation in higher level which
is error prone (and is plainly spoken ugly).

Adding a function virHostCPUHasBitmap that can be used to check
for host CPU bitmap support.

NB: There are other functions including the host CPU count that
are lacking support on all platforms, but they are too essential
in order to be bypassed.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

Signed-off-by: NNitesh Konkar <nitkon12@linux.vnet.ibm.com>

There is nothing Linux-specific in that function.  Also since commit
8c3b5bf4 mingw build is broken due to
the fact that this function is not compiled in the library.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

We will need this function shortly when implementing
nodeGetCPUStats in the test driver.
Signed-off-by: NTomáš Ryšavý <tom.rysavy.0@gmail.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Current implementation uses the dev.cpu.0.freq sysctl that is
provided by the cpufreq(4) framework and returns the actual
CPU frequency. However, there are environments where it's not available,
e.g. when running nested in KVM. In this case fall back to hw.clockrate
that reports CPU frequency at the boot time.

Resolves (hopefully):
https://bugzilla.redhat.com/show_bug.cgi?id=1369964

All Linux releases we support (RHEL6 era) include these
definitions.

If we don't HAVE_LINUX_KVM_H, we can't query /dev/kvm to discover
the limits on the number of vCPUs, so we report an error and
return a negative value instead.

Remove the local kvmpath variable from
virHostCPUGetThreadsPerSubcore() and use the file-global
KVM_DEVICE define instead.

This kvmGetMaxVCPUs() needs to be used at two different places
so move it to utils with appropriate name and mark it as private
global now.
Signed-off-by: NShivaprasad G Bhat <sbhat@linux.vnet.ibm.com>

Remove all the remaining usage of opendir.

Switch from opendir to virDirOpen everywhere we need to report an error.

Introduce a helper that only calls closedir if DIR* is non-NULL
and sets it to NULL afterwards.

The only possible error is EBADFD.
Since we only use the directory stream returned by opendir,
this should never happen.

Most the callers pass 0 in one form or another, including
vircapstest which used VIR_ARCH_NONE.

This function is plenty of ifdefs providing implementations for
Linux, *BSD and OS-X. However, if we are being build for any
other architecture, all that's left behind by preprocessor is
just a error reporting call and return of -1. In that case,
passed arguments are unused:

../../src/util/virhostcpu.c: In function 'virHostCPUGetInfo':
../../src/util/virhostcpu.c:966:33: error: unused parameter 'cpus' [-Werror=unused-parameter]
                   unsigned int *cpus,
                                 ^~~~
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

 * Fix misspelt function name:
    s/virHostCPUGetStatsFreebsd/virHostCPUGetStatsFreeBSD/
 * Mark the first argument to virHostCPUGetInfo with ATTRIBUTE_UNUSED
   as it's not actually used on non-Linux

Move all APIs with a virHostCPU name prefix out into new
util/virhostcpu.h & util/virhostcpu.c files
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In preparation for moving all the CPU related APIs out of
the nodeinfo file, give them a virHostCPU name prefix.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In preparation for moving all the memory related APIs out of
the nodeinfo file, give them a virHostMem name prefix.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Instead of having platform specific code in nodeGetInfo to
fetch CPU topology, split it all out into a new method
nodeGetCPUInfo.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The GNULIB physmem module already provides support for
the FreeBSD platform, so there's no reason to re-implement
FreeBSD portability code in libvirt. If there are bugs in
the GNULIB code, we should fix GNULIB rather than workaround
it in libvirt.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The nodeGetInfo() method currently has its own code for getting
memory size in KB, that basically just re-invents what nodeGetMemory
already does. Remove it and just call nodeGetMemory, converting its
result from bytes to KB, allowing removal of more platform specific
conditional code.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Nearly all the methods in the nodeinfo file are given a
'const char *sysfs_prefix' parameter to override the
default sysfs path (/sys/devices/system). Every single
caller passes in NULL for this, except one use in the
unit tests. Furthermore this parameter is totally
Linux-specific, when the APIs are intended to be cross
platform portable.

This removes the sysfs_prefix parameter and instead gives
a new method linuxNodeInfoSetSysFSSystemPath for use by
the test suite.

For two of the methods this hardcodes use of the constant
SYSFS_SYSTEM_PATH, since the test suite does not need to
override the path for thos methods.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The manpage for sysconf() suggest including unistd.h as the
function is declared there. Even though we are not hitting any
compile issues currently, let's include the correct header file
instead of relying on some hidden include chain.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Compiler error:

  ../../src/nodeinfo.c: In function 'nodeGetThreadsPerSubcore':
  ../../src/nodeinfo.c:2393: error: label 'out' defined but not used [-Wunused-label]
  ../../src/nodeinfo.c:2352: error: unused parameter 'arch' [-Wunused-parameter]

The nodeinfo is reporting incorrect number of cpus and incorrect host
topology on PPC64 KVM hosts. The KVM hypervisor on PPC64 needs only
the primary thread in a core to be online, and the secondaries offlined.
While scheduling a guest in, the kvm scheduler wakes up the secondaries to
run in guest context.

The host scheduling of the guests happen at the core level(as only primary
thread is online). The kvm scheduler exploits as many threads of the core
as needed by guest. Further, starting POWER8, the processor allows splitting
a physical core into multiple subcores with 2 or 4 threads each. Again, only
the primary thread in a subcore is online in the host. The KVM-PPC
scheduler allows guests to exploit all the offline threads in the subcore,
by bringing them online when needed.
(Kernel patches on split-core http://www.spinics.net/lists/kvm-ppc/msg09121.html)

Recently with dynamic micro-threading changes in ppc-kvm, makes sure
to utilize all the offline cpus across guests, and across guests with
different cpu topologies.
(https://www.mail-archive.com/kvm@vger.kernel.org/msg115978.html)

Since the offline cpus are brought online in the guest context, it is safe
to count them as online. Nodeinfo today discounts these offline cpus from
cpu count/topology calclulation, and the nodeinfo output is not of any help
and the host appears overcommited when it is actually not.

The patch carefully counts those offline threads whose primary threads are
online. The host topology displayed by the nodeinfo is also fixed when the
host is in valid kvm state.
Signed-off-by: NShivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>