netbird/gvisor
0
0
Fork 0
mirror of https://github.com/netbirdio/gvisor.git synced 2026-05-22 17:12:49 -07:00
Code Issues Packages Projects Releases Wiki Activity

netstack: remove several layers of interface nesting of LinkEndpoints

Browse Source 
runsc's NICs will just have an fdbased LinkEndpoint to write to unless the user
asks for packet logging. Before, a write from the NIC to its endpoint would go
something like:

- sniffer.endpoint.WritePackets
- packetsocket.endpoint.WritePackets
- nested.Endpoint.WritePackets
- fdbased.endpoint.WritePackets

In addition to the extra work done in some of these steps, and the slowness of
interface calls in a hot path, directly calling into an fdbased.endpoint opens
up additional optimizations (see other CLs in this chain). For example, if the
qdisc knows it's talking to an fdbased.endpoint, it can pass in persistent
structs (iovecs, mmsghdrs) rather than re-allocating them in every call to
WritePackets.

PiperOrigin-RevId: 615499448
This commit is contained in:
Kevin Krakauer
2024-03-13 12:07:50 -07:00
committed by gVisor bot
parent 26e0e5df83
commit ddb7a38802
6 changed files with 56 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files
pkg/tcpip/stack/nic.go
+17
View File
@@ -79,6 +79,13 @@ type nic struct {
qDisc QueueingDiscipline
gro groDispatcher
// deliverLinkPackets specifies whether this NIC delivers packets to
// packet sockets. It is immutable.
//
// deliverLinkPackets is off by default because some users already
// deliver link packets by explicitly calling nic.DeliverLinkPackets.
deliverLinkPackets bool
}
// makeNICStats initializes the NIC statistics and associates them to the global
@@ -174,6 +181,7 @@ func newNIC(stack *Stack, id tcpip.NICID, ep LinkEndpoint, opts NICOptions) *nic
linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]*linkResolver),
duplicateAddressDetectors: make(map[tcpip.NetworkProtocolNumber]DuplicateAddressDetector),
qDisc: qDisc,
deliverLinkPackets: opts.DeliverLinkPackets,
}
nic.linkResQueue.init(nic)
@@ -396,6 +404,11 @@ func (n *nic) writeRawPacketWithLinkHeaderInPayload(pkt *PacketBuffer) tcpip.Err
func (n *nic) writeRawPacket(pkt *PacketBuffer) tcpip.Error {
// Always an outgoing packet.
pkt.PktType = tcpip.PacketOutgoing
if n.deliverLinkPackets {
n.DeliverLinkPacket(pkt.NetworkProtocolNumber, pkt)
}
if err := n.qDisc.WritePacket(pkt); err != nil {
if _, ok := err.(*tcpip.ErrNoBufferSpace); ok {
n.stats.txPacketsDroppedNoBufferSpace.Increment()
@@ -735,6 +748,10 @@ func (n *nic) DeliverNetworkPacket(protocol tcpip.NetworkProtocolNumber, pkt *Pa
pkt.RXChecksumValidated = n.NetworkLinkEndpoint.Capabilities()&CapabilityRXChecksumOffload != 0
if n.deliverLinkPackets {
n.DeliverLinkPacket(protocol, pkt)
}
n.gro.dispatch(pkt, protocol, networkEndpoint)
}
pkg/tcpip/stack/stack.go
+4
View File
@@ -851,6 +851,10 @@ type NICOptions struct {
// GROTimeout specifies the GRO timeout. Zero bypasses GRO.
GROTimeout time.Duration
// DeliverLinkPackets specifies whether the NIC is responsible for
// delivering raw packets to packet sockets.
DeliverLinkPackets bool
}
// CreateNICWithOptions creates a NIC with the provided id, LinkEndpoint, and
runsc/boot/BUILD
-1
View File
@@ -107,7 +107,6 @@ go_library(
"//pkg/tcpip/link/ethernet",
"//pkg/tcpip/link/fdbased",
"//pkg/tcpip/link/loopback",
"//pkg/tcpip/link/packetsocket",
"//pkg/tcpip/link/qdisc/fifo",
"//pkg/tcpip/link/sniffer",
"//pkg/tcpip/link/xdp",
runsc/boot/loader.go
+5 -3
View File
@@ -62,7 +62,6 @@ import (
"gvisor.dev/gvisor/pkg/tcpip"
"gvisor.dev/gvisor/pkg/tcpip/link/ethernet"
"gvisor.dev/gvisor/pkg/tcpip/link/loopback"
"gvisor.dev/gvisor/pkg/tcpip/link/packetsocket"
"gvisor.dev/gvisor/pkg/tcpip/link/sniffer"
"gvisor.dev/gvisor/pkg/tcpip/network/arp"
"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
@@ -1406,8 +1405,11 @@ func (f *sandboxNetstackCreator) CreateStack() (inet.Stack, error) {
n := &Network{Stack: s.(*netstack.Stack).Stack}
nicID := tcpip.NICID(f.uniqueID.UniqueID())
link := DefaultLoopbackLink
linkEP := packetsocket.New(ethernet.New(loopback.New()))
opts := stack.NICOptions{Name: link.Name}
linkEP := ethernet.New(loopback.New())
opts := stack.NICOptions{
Name: link.Name,
DeliverLinkPackets: true,
}
if err := n.createNICWithAddrs(nicID, linkEP, opts, link.Addresses); err != nil {
return nil, err
runsc/boot/network.go
+27 -24
View File
@@ -32,7 +32,6 @@ import (
"gvisor.dev/gvisor/pkg/tcpip/link/ethernet"
"gvisor.dev/gvisor/pkg/tcpip/link/fdbased"
"gvisor.dev/gvisor/pkg/tcpip/link/loopback"
"gvisor.dev/gvisor/pkg/tcpip/link/packetsocket"
"gvisor.dev/gvisor/pkg/tcpip/link/qdisc/fifo"
"gvisor.dev/gvisor/pkg/tcpip/link/sniffer"
"gvisor.dev/gvisor/pkg/tcpip/link/xdp"
@@ -170,6 +169,9 @@ type CreateLinksAndRoutesArgs struct {
// PCAP indicates that FilePayload also contains a PCAP log file.
PCAP bool
// LogPackets indicates that packets should be logged.
LogPackets bool
// NATBlob indicates whether FilePayload also contains an iptables NAT
// ruleset.
NATBlob bool
@@ -249,12 +251,13 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
nicID++
nicids[link.Name] = nicID
linkEP := packetsocket.New(ethernet.New(loopback.New()))
linkEP := ethernet.New(loopback.New())
log.Infof("Enabling loopback interface %q with id %d on addresses %+v", link.Name, nicID, link.Addresses)
opts := stack.NICOptions{
Name: link.Name,
GROTimeout: link.GvisorGROTimeout,
Name: link.Name,
GROTimeout: link.GvisorGROTimeout,
DeliverLinkPackets: true,
}
if err := n.createNICWithAddrs(nicID, linkEP, opts, link.Addresses); err != nil {
return err
@@ -319,21 +322,20 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
return err
}
// Wrap linkEP in a sniffer to enable packet logging.
var sniffEP stack.LinkEndpoint
// Setup packet logging if requested.
if args.PCAP {
newFD, err := unix.Dup(int(args.FilePayload.Files[fdOffset].Fd()))
if err != nil {
return fmt.Errorf("failed to dup pcap FD: %v", err)
}
const packetTruncateSize = 4096
sniffEP, err = sniffer.NewWithWriter(packetsocket.New(linkEP), os.NewFile(uintptr(newFD), "pcap-file"), packetTruncateSize)
linkEP, err = sniffer.NewWithWriter(linkEP, os.NewFile(uintptr(newFD), "pcap-file"), packetTruncateSize)
if err != nil {
return fmt.Errorf("failed to create PCAP logger: %v", err)
}
fdOffset++
} else {
sniffEP = sniffer.New(packetsocket.New(linkEP))
} else if args.LogPackets {
linkEP = sniffer.New(linkEP)
}
var qDisc stack.QueueingDiscipline
@@ -341,16 +343,17 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
case config.QDiscNone:
case config.QDiscFIFO:
log.Infof("Enabling FIFO QDisc on %q", link.Name)
qDisc = fifo.New(sniffEP, runtime.GOMAXPROCS(0), 1000)
qDisc = fifo.New(linkEP, runtime.GOMAXPROCS(0), 1000)
}
log.Infof("Enabling interface %q with id %d on addresses %+v (%v) w/ %d channels", link.Name, nicID, link.Addresses, mac, link.NumChannels)
opts := stack.NICOptions{
Name: link.Name,
QDisc: qDisc,
GROTimeout: link.GvisorGROTimeout,
Name: link.Name,
QDisc: qDisc,
GROTimeout: link.GvisorGROTimeout,
DeliverLinkPackets: true,
}
if err := n.createNICWithAddrs(nicID, sniffEP, opts, link.Addresses); err != nil {
if err := n.createNICWithAddrs(nicID, linkEP, opts, link.Addresses); err != nil {
return err
}
@@ -398,6 +401,7 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
}
}
// Setup packet logging if requested.
mac := tcpip.LinkAddress(link.LinkAddress)
linkEP, err := xdp.New(&xdp.Options{
FD: fd,
@@ -411,21 +415,19 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
return err
}
// Wrap linkEP in a sniffer to enable packet logging.
var sniffEP stack.LinkEndpoint
if args.PCAP {
newFD, err := unix.Dup(int(args.FilePayload.Files[fdOffset].Fd()))
if err != nil {
return fmt.Errorf("failed to dup pcap FD: %v", err)
}
const packetTruncateSize = 4096
sniffEP, err = sniffer.NewWithWriter(packetsocket.New(linkEP), os.NewFile(uintptr(newFD), "pcap-file"), packetTruncateSize)
linkEP, err = sniffer.NewWithWriter(linkEP, os.NewFile(uintptr(newFD), "pcap-file"), packetTruncateSize)
if err != nil {
return fmt.Errorf("failed to create PCAP logger: %v", err)
}
fdOffset++
} else {
sniffEP = sniffer.New(packetsocket.New(linkEP))
} else if args.LogPackets {
linkEP = sniffer.New(linkEP)
}
var qDisc stack.QueueingDiscipline
@@ -433,16 +435,17 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct
case config.QDiscNone:
case config.QDiscFIFO:
log.Infof("Enabling FIFO QDisc on %q", link.Name)
qDisc = fifo.New(sniffEP, runtime.GOMAXPROCS(0), 1000)
qDisc = fifo.New(linkEP, runtime.GOMAXPROCS(0), 1000)
}
log.Infof("Enabling interface %q with id %d on addresses %+v (%v) w/ %d channels", link.Name, nicID, link.Addresses, mac, link.NumChannels)
opts := stack.NICOptions{
Name: link.Name,
QDisc: qDisc,
GROTimeout: link.GvisorGROTimeout,
Name: link.Name,
QDisc: qDisc,
GROTimeout: link.GvisorGROTimeout,
DeliverLinkPackets: true,
}
if err := n.createNICWithAddrs(nicID, sniffEP, opts, link.Addresses); err != nil {
if err := n.createNICWithAddrs(nicID, linkEP, opts, link.Addresses); err != nil {
return err
}
runsc/sandbox/network.go
+3
View File
@@ -526,6 +526,9 @@ func removeAddress(source netlink.Link, ipAndMask string) error {
}
func pcapAndNAT(args *boot.CreateLinksAndRoutesArgs, conf *config.Config) error {
// Possibly enable packet logging.
args.LogPackets = conf.LogPackets
// Pass PCAP log file if present.
if conf.PCAP != "" {
args.PCAP = true