Re: [PATCH 3/3] domain_conf: add SCHED_DEADLINE support in the XML configuration

Users can set SCHED_DEADLINE as a scheduling policy. For example, for setting runtime = 10000000, deadline = 15000000 and period = 20000000 for vcpus 0-2: <cputune> ... <vcpusched vcpus="0-2" scheduler="deadline" runtime="10000000" deadline="15000000" period="20000000"/> ... </cputune> Update release notes accordingly. Signed-off-by: Sasha Algisi <sasha.algisi(a)edu.unito.it&gt; Signed-off-by: Dario Faggioli <dfaggioli(a)suse.com&gt; --- NEWS.rst | 5 +++ docs/formatdomain.rst | 16 +++++++--- src/conf/domain_conf.c | 52 ++++++++++++++++++++++++++++--- src/conf/schemas/domaincommon.rng | 16 ++++++++++ 4 files changed, 80 insertions(+), 9 deletions(-) diff --git a/NEWS.rst b/NEWS.rst index ef298da539..23484afdc2 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -17,6 +17,11 @@ v8.7.0 (unreleased) * **New features** + * qemu: support for SCHED_DEADLINE scheduling + + Users can now use the SCHED_DEADLINE scheduling policy for tasks + associated to virtual CPUs, IO Threads and Emulator processes. + * **Improvements**

* **Bug fixes** diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index 1ed969ac3e..216262b79d 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -910,10 +910,11 @@ CPU Tuning support since 2.1.0` ``vcpusched``, ``iothreadsched`` and ``emulatorsched`` The optional ``vcpusched``, ``iothreadsched`` and ``emulatorsched`` elements - specify the scheduler type (values ``batch``, ``idle``, ``fifo``, ``rr``) for - particular vCPU, IOThread and emulator threads respectively. For ``vcpusched`` - and ``iothreadsched`` the attributes ``vcpus`` and ``iothreads`` select which - vCPUs/IOThreads this setting applies to, leaving them out sets the default. + specify the scheduler type (values ``batch``, ``idle``, ``fifo``, ``rr``, + ``deadline`` :since:`Since 8.7.0`) for particular vCPU, IOThread and emulator + threads respectively. For ``vcpusched`` and ``iothreadsched`` the attributes + ``vcpus`` and ``iothreads`` select which vCPUs/IOThreads this setting applies + to, leaving them out sets the default. The element ``emulatorsched`` does not have that attribute. Valid ``vcpus`` values start at 0 through one less than the number of vCPU's defined for the domain. Valid ``iothreads`` values are described in the `IOThreads Allocation`_ @@ -923,6 +924,13 @@ CPU Tuning priority must be specified as well (and is ignored for non-real-time ones). The value range for the priority depends on the host kernel (usually 1-99). :since:`Since 1.2.13` ``emulatorsched`` :since:`since 5.3.0` + For SCHED_DEADLINE (``deadline``), runtime , deadline and period must also + be specified (they are ignored in other schedulers). It must always be true + that: runtime <= deadline <= period. + The values are specified in nanoseconds. The valid range for the parameters + is [1024, 2^63-1] (but a smaller one can be put in place via sysctl). The + period can be set to 0, in which case, a period equal to the deadline is + used.

``cachetune`` :since:`Since 4.1.0` Optional ``cachetune`` element can control allocations for CPU caches using the resctrl on the host. Whether or not is this supported can be gathered diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index e85cc1f809..86ada8f147 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -16693,7 +16693,10 @@ virDomainLoaderDefParseXML(virDomainLoaderDef *loader, static int virDomainSchedulerParseCommonAttrs(xmlNodePtr node, virProcessSchedPolicy *policy, - int *priority) + int *priority, + uint64_t *runtime, + uint64_t *deadline, + uint64_t *period)