On 06/15/2017 10:17 AM, sferdjao@redhat.com wrote:
From: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@redhat.com>
In this commit we introduce 'poll_us' attribute which will be passed then to the QEMU command line to enable support of busy polling. This commit also take into account that attribute to generate the XML.
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@redhat.com> --- src/conf/domain_conf.c | 16 ++++++++++++++++ src/conf/domain_conf.h | 1 + 2 files changed, 17 insertions(+)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 0507ec1..803f517 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -9748,6 +9748,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, char *event_idx = NULL; char *queues = NULL; char *rx_queue_size = NULL; + char *pollus = NULL;
since the option is "poll-us", but you can't have "-" in an identifier name, this should either be "poll_us", or "pollUS" (there is some amount of preference for camelCase in C and XML identifier names in libvirt, but it is by no means universal, so probably best just to go along with what's done for nearby identifiers in a similar class, e.g. event_idx). (Of course some purists would say that we shouldn't include the type of units in the name, but since this number is so specific to a particular driver, I think it's reasonable to treat it as an opaque setting, named "poll-us", with no units-type associated with it).
char *str = NULL; char *filter = NULL; char *internal = NULL; @@ -9921,6 +9922,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, event_idx = virXMLPropString(cur, "event_idx"); queues = virXMLPropString(cur, "queues"); rx_queue_size = virXMLPropString(cur, "rx_queue_size"); + pollus = virXMLPropString(cur, "poll_us"); } else if (xmlStrEqual(cur->name, BAD_CAST "filterref")) { if (filter) { virReportError(VIR_ERR_XML_ERROR, "%s", @@ -10318,6 +10320,17 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, } def->driver.virtio.rx_queue_size = q; } + if (pollus) { + unsigned int us; + if (virStrToLong_uip(pollus, NULL, 10, &us) < 0) { + virReportError(VIR_ERR_XML_DETAIL, + _("'poll_us' attribute must be positive number: %s"),
"...must be positive" or "...must be a positive integer"
+ pollus); + goto error; + } + if (us > 1) + def->driver.virtio.pollus = us; + } if ((str = virXPathString("string(./driver/host/@csum)", ctxt))) { if ((val = virTristateSwitchTypeFromString(str)) <= 0) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, @@ -10515,6 +10528,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, VIR_FREE(event_idx); VIR_FREE(queues); VIR_FREE(rx_queue_size); + VIR_FREE(pollus); VIR_FREE(str); VIR_FREE(filter); VIR_FREE(type); @@ -22308,6 +22322,8 @@ virDomainVirtioNetDriverFormat(char **outstr, if (def->driver.virtio.rx_queue_size) virBufferAsprintf(&buf, " rx_queue_size='%u'", def->driver.virtio.rx_queue_size); + if (def->driver.virtio.pollus) + virBufferAsprintf(&buf, " poll_us='%u'", def->driver.virtio.pollus);
virDomainVirtioOptionsFormat(&buf, def->virtio);
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h index e67b6fd..d97d776 100644 --- a/src/conf/domain_conf.h +++ b/src/conf/domain_conf.h @@ -967,6 +967,7 @@ struct _virDomainNetDef { virTristateSwitch event_idx; unsigned int queues; /* Multiqueue virtio-net */ unsigned int rx_queue_size; + unsigned int pollus; /* busy polling for tap */ struct { virTristateSwitch csum; virTristateSwitch gso;
Generally I like to have the schema change (RNG file) and formatdomain.html.in (documentation) change, along with xml2xml tests. in the same commit as the change to the parser/formatter, but you've included them in the commit that connects the parser/formatter change into the qemu driver. Of course it all comes out the same in the end, but separating it in the way I suggest makes each patch self documenting and self-testing (xml2argv tests will still be added in the final patch).