On Sat, Nov 20, 2021 at 03:20:47 -0500, huangy81@chinatelecom.cn wrote:
From: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
introduce dirty_ring_size in struct "_virDomainDef" to hold the ring size configured by user, and pass dirty_ring_size when building qemu commandline if dirty ring feature enabled.
Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn> --- src/conf/domain_conf.c | 76 ++++++++++++++++++++++++++++++++++++++++- src/conf/domain_conf.h | 4 +++ src/qemu/qemu_command.c | 3 ++ 3 files changed, 82 insertions(+), 1 deletion(-)
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@@ -4826,6 +4827,18 @@ virDomainDefPostParseMemtune(virDomainDef *def) }
+static void +virDomainDefPostParseFeatures(virDomainDef *def) +{ + if (def->features[VIR_DOMAIN_FEATURE_KVM] == VIR_TRISTATE_SWITCH_ON && + def->kvm_features[VIR_DOMAIN_KVM_DIRTY_RING] == VIR_TRISTATE_SWITCH_ON && + def->dirty_ring_size == 0) { + /* set 4096 as default size if dirty ring size not congfigured */
Instead of this quite obvious thing I'd prefer a justification of why this setting is done in the global post-parse function rather than the qemu specific one. If there is no good reason to have it globally, please move it to the qemu-specific one.
+ def->dirty_ring_size = 4096; + } +}
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@@ -17566,8 +17581,10 @@ virDomainFeaturesHyperVDefParse(virDomainDef *def,
static int virDomainFeaturesKVMDefParse(virDomainDef *def, + xmlXPathContextPtr ctxt, xmlNodePtr node) { + xmlNodePtr tmp_node = ctxt->node;
We have an established approach for resetting the XPath context. Please use it, as ...[1].
def->features[VIR_DOMAIN_FEATURE_KVM] = VIR_TRISTATE_SWITCH_ON;
node = xmlFirstElementChild(node); @@ -17589,9 +17606,37 @@ virDomainFeaturesKVMDefParse(virDomainDef *def,
def->kvm_features[feature] = value;
+ /* dirty ring feature should parse size property */ + if ((virDomainKVM) feature == VIR_DOMAIN_KVM_DIRTY_RING) { + if (((virDomainKVM) feature) == VIR_DOMAIN_KVM_DIRTY_RING && + value == VIR_TRISTATE_SWITCH_ON) { + ctxt->node = node; + + if (virXMLPropString(node, "size")) {
virXMLPropString returns an allocated string, so this is leaking memory.
+ if (virXPathUInt("string(./@size)", ctxt, + &def->dirty_ring_size) < 0) {
If you fetch the 'size' attribute via virXMLPropString there's no need to re-parse it again using XPath. In fact you can avoid dragging xpath into this function altogether.
+ virReportError(VIR_ERR_XML_ERROR, "%s", + _("invalid number of dirty ring size")); + return -1;
... [1] on this error path it's not fixed.
+ } + + if ((def->dirty_ring_size & (def->dirty_ring_size - 1)) != 0 ||
We have a function/macro for checking power-of-two.
+ def->dirty_ring_size < 1024 || + def->dirty_ring_size > 65536) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("dirty ring must be power of 2 " + "and ranges [1024, 65536]"));
Also per coding style error messages are not to be broken up. Additionally, is this a qemu-specific range?
+ return -1; + } + } + } + } + node = xmlNextElementSibling(node); }
+ ctxt->node = tmp_node; + return 0; }
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