By probing for qemu machine types, we increased the time of a
GetCapabilities call from 100us to a whopping 60ms.
This patch takes the approach of only probing for machine types
when the mtime of the emulator binary changed since the last time
the capabilities were generated.
* src/capabilities.h: cache the emulator binary mtime
* src/qemu_conf.c: add qemudGetOldMachines() to copy the machine
types from the old caps struct if the mtime for the binary hasn't
changed
* src/qemu_conf.h, src/qemu_driver.c: pass the old caps pointer to
qemudCapsInit()
A subsequent commit will add a "canonical" field to this structure,
this patch basically just prepares the way for that.
The new type is added, along with virCapabilitiesAlloc/FreeMachines()
helpers and a whole bunch of code to make the transition.
One quirk is that virCapabilitiesAddGuestDomain() and
virCapabilitiesAddGuest() take ownership of the machine list rather
than duping it. This makes sense to avoid needless copying.
* src/capabilities.h: add the virCapsGuestMachine struct and use it
in virCapsGuestDomainInfo, add prototypes for new functions and
update the AddGuest() prototypes
* src/capabilities.c: add code for allocating and freeing the new
type, change the machines parameter to AddGuest() etc.
* src/libvirt_private.syms: export the new helpers
* src/qemu_conf.c: update all the machine type code to use the new
struct
* src/xen_internal.c: ditto
* tests/testutilsqemu.c: ditto
Certain drivers always need an 'emulator' specified in the XML (qemu and lxc
at least). Store this info in capabilities.
We will eventually use this to move default emulator handling out of
drivers and into domain_conf.*
