5:06 a.m.
On 03/06/2015 04:46 AM, Daniel P. Berrange wrote:
On Thu, Mar 05, 2015 at 09:03:02PM -0500, John Ferlan wrote:
> Add virDomainGetIOThreadPin to fetch the pinned CPU affinity map
> for one IOThread.
>
> Add virDomainPinIOThread to allow setting the CPU affinity for a
> specific IOThread.
>
> Signed-off-by: John Ferlan <jferlan(a)redhat.com>
> ---
> include/libvirt/libvirt-domain.h | 10 +++
> src/driver-hypervisor.h | 16 +++++
> src/libvirt-domain.c | 152 +++++++++++++++++++++++++++++++++++++++
> src/libvirt_public.syms | 2 +
> 4 files changed, 180 insertions(+)
>
> diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
> index 9487b80..fc35cd2 100644
> --- a/include/libvirt/libvirt-domain.h
> +++ b/include/libvirt/libvirt-domain.h
> @@ -1609,6 +1609,16 @@ void
virDomainIOThreadsInfoFree(virDomainIOThreadInfoPtr info);
> int virDomainGetIOThreadsInfo(virDomainPtr domain,
> virDomainIOThreadInfoPtr **info,
> unsigned int flags);
> +int virDomainGetIOThreadPin (virDomainPtr domain,
> + unsigned int iothread_id,
> + unsigned char *cpumap,
> + int maplen,
> + unsigned int flags);
Isn't the GetIOThreadsInfo method & struct already reporting the pinning
info for all current IO threads ? I'm not sure what the difference is
between what GetIOThreadsInfo and GetIOThreadPin is ?
+struct _virDomainIOThreadInfo {
+ unsigned int iothread_id; /* IOThread ID */
+ unsigned char *cpumap; /* CPU map for thread. A pointer to an */
+ /* array of real CPUs (in 8-bit bytes) */
+ int cpumaplen; /* cpumap size */
+};
These fields match all the parameters in GetIOThreadPin, so it seems adding a
GetIOThreadPin is redundant,
Yes - although based on reviews from yesterday it wasn't totally clear
if having a GetIOThreadPin in addition to GetIOThreadsInfo was
requested, so I added it to be "safe", but can remove it.
There is a GetVcpus and a GetVcpuPinInfo and the IOThreads code mirrors
that.
Tks -
John
> +int virDomainPinIOThread(virDomainPtr domain,
> + unsigned int iothread_id,
> + unsigned char *cpumap,
> + int maplen,
> + unsigned int flags);
This is fine though
> +/**
> + * virDomainPinIOThread:
> + * @domain: a domain object
> + * @iothread_id: either the thread_id to modify or a count of IOThreads
> + * to be added or removed from the domain depending on the @flags setting
This can be updated now.
> + * @cpumap: pointer to a bit map of real CPUs (in 8-bit bytes) (IN)
> + * Each bit set to 1 means that corresponding CPU is usable.
> + * Bytes are stored in little-endian order: CPU0-7, 8-15...
> + * In each byte, lowest CPU number is least significant bit.
> + * @maplen: number of bytes in cpumap, from 1 up to size of CPU map in
> + * underlying virtualization system (Xen...).
> + * If maplen < size, missing bytes are set to zero.
> + * If maplen > size, failure code is returned.
> + * @flags: bitwise-OR of virDomainModificationImpact
> + *
> + * Dynamically change the real CPUs which can be allocated to an IOThread.
> + * This function may require privileged access to the hypervisor.
> + *
> + * @flags may include VIR_DOMAIN_AFFECT_LIVE or VIR_DOMAIN_AFFECT_CONFIG.
> + * Both flags may be set.
> + * If VIR_DOMAIN_AFFECT_LIVE is set, the change affects a running domain
> + * and may fail if domain is not alive.
> + * If VIR_DOMAIN_AFFECT_CONFIG is set, the change affects persistent state,
> + * and will fail for transient domains. If neither flag is specified (that is,
> + * @flags is VIR_DOMAIN_AFFECT_CURRENT), then an inactive domain modifies
> + * persistent setup, while an active domain is hypervisor-dependent on whether
> + * just live or both live and persistent state is changed.
> + * Not all hypervisors can support all flag combinations.
> + *
> + * See also virDomainGetIOThreadsInfo for querying this information.
> + *
> + * Returns 0 in case of success, -1 in case of failure.
> + */
> +int
> +virDomainPinIOThread(virDomainPtr domain,
> + unsigned int iothread_id,
> + unsigned char *cpumap,
> + int maplen,
> + unsigned int flags)
> +{
> + virConnectPtr conn;
> +
> + VIR_DOMAIN_DEBUG(domain, "iothread_id=%u, cpumap=%p, maplen=%d",
> + iothread_id, cpumap, maplen);
> +
> + virResetLastError();
> +
> + virCheckDomainReturn(domain, -1);
> + conn = domain->conn;
> +
> + virCheckReadOnlyGoto(conn->flags, error);
> + if ((unsigned short) iothread_id != iothread_id) {
> + virReportError(VIR_ERR_OVERFLOW, _("input too large: %u"),
> + iothread_id);
> + goto error;
> + }
> + virCheckPositiveArgGoto(iothread_id, error);
> + virCheckNonNullArgGoto(cpumap, error);
> + virCheckPositiveArgGoto(maplen, error);
> +
> + if (conn->driver->domainPinIOThread) {
> + int ret;
> + ret = conn->driver->domainPinIOThread(domain, iothread_id,
> + cpumap, maplen, flags);
> + if (ret < 0)
> + goto error;
> + return ret;
> + }
> +
> + virReportUnsupportedError();
> +
> + error:
> + virDispatchError(domain->conn);
> + return -1;
> +}
Regards,
Daniel