hypervisor: Add network bandwidth and operations rate limiters

In a similar way to what's already exposed as RxRateLimiterMaxRate and
TxRateLimiterMaxRate, let's add four new fields to the Hypervisor's
configuration.

The values added are related to bandwidth and operations rate limiters,
which have to be added so we can expose I/O throttling configurations to
users using Cloud Hypervisor as their preferred VMM.

The reason we cannot simply re-use {Rx,Tx}RateLimiterMaxRate is because
Cloud Hypervisor exposes a single MaxRate to be used for both inbound
and outbound queues.

The newly added fields are:
* NetRateLimiterBwMaxRate, defined in bits per second, which is used to
  control the network I/O bandwidth at the VM level.
* NetRateLimiterBwOneTimeBurst, also defined in bits per second, which
  is used to define an *initial* max rate, which doesn't replenish.
* NetRateLimiterOpsMaxRate, the operations per second equivalent of the
  NetRateLimiterBwMaxRate.
* NetRateLimiterOpsOneTimeBurst, the operations per second equivalent of
  the NetRateLimiterBwOneTimeBurst.

For now those extra fields have only been added to the hypervisor's
configuration and they'll be used in the coming patches of this very
same series.

Signed-off-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>

src/runtime/pkg/katautils/config.go

@@ -108,6 +108,10 @@ type hypervisor struct {
 	RxRateLimiterMaxRate          uint64   `toml:"rx_rate_limiter_max_rate"`
 	TxRateLimiterMaxRate          uint64   `toml:"tx_rate_limiter_max_rate"`
 	MemOffset                     uint64   `toml:"memory_offset"`
+	NetRateLimiterBwMaxRate       int64    `toml:"net_rate_limiter_bw_max_rate"`
+	NetRateLimiterBwOneTimeBurst  int64    `toml:"net_rate_limiter_bw_one_time_burst"`
+	NetRateLimiterOpsMaxRate      int64    `toml:"net_rate_limiter_ops_max_rate"`
+	NetRateLimiterOpsOneTimeBurst int64    `toml:"net_rate_limiter_ops_one_time_burst"`
 	VirtioFSCacheSize             uint32   `toml:"virtio_fs_cache_size"`
 	DefaultMaxVCPUs               uint32   `toml:"default_maxvcpus"`
 	MemorySize                    uint32   `toml:"default_memory"`
@@ -490,6 +494,34 @@ func (h hypervisor) getTxRateLimiterCfg() uint64 {
 	return h.TxRateLimiterMaxRate
 }
 
+func (h hypervisor) getNetRateLimiterBwMaxRate() int64 {
+	return h.NetRateLimiterBwMaxRate
+}
+
+func (h hypervisor) getNetRateLimiterBwOneTimeBurst() int64 {
+	if h.NetRateLimiterBwOneTimeBurst != 0 && h.getNetRateLimiterBwMaxRate() == 0 {
+		kataUtilsLogger.Warn("The NetRateLimiterBwOneTimeBurst is set but NetRateLimiterBwMaxRate is not set, this option will be ignored.")
+
+		h.NetRateLimiterBwOneTimeBurst = 0
+	}
+
+	return h.NetRateLimiterBwOneTimeBurst
+}
+
+func (h hypervisor) getNetRateLimiterOpsMaxRate() int64 {
+	return h.NetRateLimiterOpsMaxRate
+}
+
+func (h hypervisor) getNetRateLimiterOpsOneTimeBurst() int64 {
+	if h.NetRateLimiterOpsOneTimeBurst != 0 && h.getNetRateLimiterOpsMaxRate() == 0 {
+		kataUtilsLogger.Warn("The NetRateLimiterOpsOneTimeBurst is set but NetRateLimiterOpsMaxRate is not set, this option will be ignored.")
+
+		h.NetRateLimiterOpsOneTimeBurst = 0
+	}
+
+	return h.NetRateLimiterOpsOneTimeBurst
+}
+
 func (h hypervisor) getIOMMUPlatform() bool {
 	if h.IOMMUPlatform {
 		kataUtilsLogger.Info("IOMMUPlatform is enabled by default.")

src/runtime/virtcontainers/hypervisor.go

@@ -386,6 +386,24 @@ type HypervisorConfig struct {
 	// TxRateLimiterMaxRate is used to control network I/O outbound bandwidth on VM level.
 	TxRateLimiterMaxRate uint64
 
+	// NetRateLimiterBwRate is used to control network I/O bandwidth on VM level.
+	// The same value, defined in bits per second, is used for inbound and outbound bandwidth.
+	NetRateLimiterBwMaxRate int64
+
+	// NetRateLimiterBwOneTimeBurst is used to control network I/O bandwidth on VM level.
+	// This increases the initial max rate and this initial extra credit does *NOT* replenish
+	// and can be used for an *initial* burst of data.
+	NetRateLimiterBwOneTimeBurst int64
+
+	// NetRateLimiterOpsRate is used to control network I/O operations on VM level.
+	// The same value, defined in operations per second, is used for inbound and outbound bandwidth.
+	NetRateLimiterOpsMaxRate int64
+
+	// NetRateLimiterOpsOneTimeBurst is used to control network I/O operations on VM level.
+	// This increases the initial max rate and this initial extra credit does *NOT* replenish
+	// and can be used for an *initial* burst of data.
+	NetRateLimiterOpsOneTimeBurst int64
+
 	// MemOffset specifies memory space for nvdimm device
 	MemOffset uint64