Re: [libvirt] [PATCH v3 3/9] qemu: Implement the qemu driver fetch for IOThreads

Depending on the flags passed, either attempt to return the active/live IOThread data for the domain or the config data. The active/live path will call into the Monitor in order to get the IOThread data and then correlate the thread_id's returned from the monitor to the currently running system/threads in order to ascertain the affinity for each iothread_id. The config path will map each of the configured IOThreads and return any configured iothreadspin data Both paths will peruse the 'targetDef' domain list looking for 'disks' that have been assigned to a specific IOThread. An IOThread may have no resources associated Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/qemu/qemu_driver.c | 281 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 281 insertions(+)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 1bbbe9b..2c9d08c 100644

+static int + + if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_QUERY) < 0) + goto cleanup; + + if (!virDomainObjIsActive(vm)) { + virReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("cannot list IOThreads for an inactive domain")); + goto endjob; + } + + priv = vm->privateData; + if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_OBJECT_IOTHREAD)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("IOThreads not supported with this binary")); + goto endjob; + } + + if (qemuDomainObjEnterMonitorAsync(driver, vm, QEMU_ASYNC_JOB_NONE) < 0) + goto endjob;

+ for (i = 0; i < targetDef->iothreads; i++) { + if (VIR_ALLOC(info_ret[i]) < 0) + goto cleanup; + + /* IOThreads being counting at 1 */ + info_ret[i]->iothread_id = i + 1; + + if (VIR_ALLOC_N(info_ret[i]->cpumap, maplen) < 0) + goto cleanup; + + /* Initialize the cpumap */ + info_ret[i]->cpumaplen = maplen; + memset(info_ret[i]->cpumap, 0xff, maplen); + if (maxcpu % 8) + info_ret[i]->cpumap[maplen - 1] &= (1 << maxcpu % 8) - 1;

+ } + + /* If iothreadspin setting exists, there are unused physical cpus */ + iothreadspin_list = targetDef->cputune.iothreadspin;

+ for (i = 0; i < targetDef->cputune.niothreadspin; i++) { + /* vcpuid is the iothread_id... + * iothread_id is the index into info_ret + 1, so we can + * assume that the info_ret index we want is vcpuid - 1 + */ + cpumap = info_ret[iothreadspin_list[i]->vcpuid - 1]->cpumap; + cpumask = iothreadspin_list[i]->cpumask; + + for (pcpu = 0; pcpu < maxcpu; pcpu++) { + if (virBitmapGetBit(cpumask, pcpu, &pinned) < 0) + goto cleanup; + if (!pinned) + VIR_UNUSE_CPU(cpumap, pcpu); + } + } +