10:54 a.m.
On 01/27/2012 07:59 AM, Daniel P. Berrange wrote:
From: "Daniel P. Berrange" <berrange(a)redhat.com>
To assist people in verifying that their host is operating in an
optimal manner, provide a 'virt-host-validate' command. For each
type of hypervisor, it will check any pre-requisites, or other
good recommendations and report what's working & what is not.
eg
# virt-host-validate
QEMU: Checking for device /dev/kvm : FAIL
(Check that the 'kvm-intel' or 'kvm-amd' modules are loaded & the BIOS
has enabled virtualization)
QEMU: Checking for device /dev/vhost : WARN (Load
the 'vhost_net' module to improve performance of virtio networking)
QEMU: Checking for device /dev/net/tun : PASS
LXC: Checking for Linux >= 2.6.26 : PASS
This warns people if they have vmx/svm, but don't have /dev/kvm. It
also warns about missing /dev/vhost net.
In version 2:
- Add to RPM specs
- Add man page
- Use getopt to parse --help, --version & --quiet options
- Don't use VT100 escape codes unless on a tty
- Disable QEMU / LXC checks if not compiled into libvirt
Looks like you hit my v1 review comments.
+++ b/tools/virt-host-validate-common.c
@@ -0,0 +1,214 @@
+/*
+ * virt-host-validate-common.c: Sanity check helper APis
s/APis/APIs/
+int virHostValidateDevice(const char *hvname,
+ const char *devname,
+ virHostValidateLevel level,
+ const char *hint)
+{
+ virHostMsgCheck(hvname, "for device %s", devname);
+
+ if (access(devname, R_OK|W_OK) < 0) {
+ virHostMsgFail(level, hint);
This could have different failures, depending on whether it is called as
root or as an ordinary user; should we be trying to refine things if
/dev/kvm exists with 600 permissions but the current euid can't
read/write it?
+int virHostValidateHasCPUFlag(const char *name)
+{
+ FILE *fp = fopen("/proc/cpuinfo", "r");
+ int ret = 0;
You're using this like a bool, so maybe s/int/bool/ and s/0/false/ make
sense.
+
+ if (virParseVersionString(uts.release, &thisversion, true) < 0) {
+ virHostMsgFail(level, hint);
+ return -1;
+ }
+
+ micro = (thisversion & 0xff);
+ minor = ((thisversion >> 8) & 0xff);
+ major = ((thisversion >> 16) & 0xff);
+
+ if (major > ((version >> 16) & 0xff)) {
+ virHostMsgPass();
+ return 0;
+ } else if (major < ((version >> 16) & 0xff)) {
+ virHostMsgFail(level, hint);
+ return -1;
+ }
Rather than break things down and check major/minor/micro independently,
why not just check if thisversion >= version and get all three checks
done at once?
+++ b/tools/virt-host-validate-common.h
@@ -0,0 +1,57 @@
+/*
+ * virt-host-validate-common.h: Sanity check helper APis
s/APis/APIs/ (copy-paste strikes again :)
+
+int virHostValidateQEMU(void)
+{
+ int ret = 0;
+
+ if (virHostValidateHasCPUFlag("svm") ||
+ virHostValidateHasCPUFlag("vmx")) {
+ if (virHostValidateDevice("QEMU", "/dev/kvm",
+ VIR_HOST_VALIDATE_FAIL,
+ _("Check that the 'kvm-intel' or
'kvm-amd' modules are "
+ "loaded & the BIOS has enabled
virtualization")) < 0)
+ ret = -1;
+ }
Should we have an else clause with VIR_HOST_VALIDATE_WARN that hardware
lacks virtualization, therefore guests will run slower, when this is run
on older cpus?
+
+ if (virHostValidateDevice("QEMU", "/dev/vhost-net",
+ VIR_HOST_VALIDATE_WARN,
+ _("Load the 'vhost_net' module to improve
performance "
+ "of virtio networking")) < 0)
+ ret = -1;
+
+ if (virHostValidateDevice("QEMU", "/dev/net/tun",
+ VIR_HOST_VALIDATE_FAIL,
+ _("Load the 'tun' module to enable networking
for QEMU guests")) < 0)
+ ret = -1;
+
+ return ret;
+}
Cool idea for another qemu validation - if !HAVE_YAJL, but qemu version
is 0.15 or newer, then complain that the libvirt binary lacks support
for QMP.
+ while ((c = getopt_long(argc, argv, "hvq", argOptions,
NULL)) != -1) {
+ switch (c) {
+ case 'v':
+ show_version(stdout, argv[0]);
+ return EXIT_SUCCESS;
Technically, we should still check for write errors to stdout, but
that's a bigger patch (gnulib provides a close-stdout module that lets
you add an atexit() hook to automate things, but it is not LGPLv2+), and
I'm okay if we overlook it for now.
+
+#if WITH_QEMU
+ if ((!hvname || STREQ(hvname, "qemu")) &&
+ virHostValidateQEMU() < 0)
+ ret = EXIT_FAILURE;
+#endif
Needs:
#else
if (STREQ(hvname, "qemu"))
fail; this libvirt was not compiled with qemu support
+
+#if WITH_LXC
+ if ((!hvname || STREQ(hvname, "lxc")) &&
+ virHostValidateLXC() < 0)
+ ret = EXIT_FAILURE;
+#endif
A similar #else complaining about no lxc support.
ACK - there are a bigger ideas for additional improvements that should
be followup patches, but what you have is reasonable for committing now
once you fix the minor typos.
--
Eric Blake eblake(a)redhat.com +1-919-301-3266
Libvirt virtualization library http://libvirt.org