diff options
Diffstat (limited to 'pkg/flipcall/flipcall.go')
| -rw-r--r-- | pkg/flipcall/flipcall.go | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/pkg/flipcall/flipcall.go b/pkg/flipcall/flipcall.go index 8d8309a73..88588ba0e 100644 --- a/pkg/flipcall/flipcall.go +++ b/pkg/flipcall/flipcall.go @@ -22,6 +22,7 @@ import ( "sync/atomic" "golang.org/x/sys/unix" + "gvisor.dev/gvisor/pkg/memutil" ) // An Endpoint provides the ability to synchronously transfer data and control @@ -96,9 +97,9 @@ func (ep *Endpoint) Init(side EndpointSide, pwd PacketWindowDescriptor, opts ... if pwd.Length > math.MaxUint32 { return fmt.Errorf("packet window size (%d) exceeds maximum (%d)", pwd.Length, math.MaxUint32) } - m, e := packetWindowMmap(pwd) - if e != 0 { - return fmt.Errorf("failed to mmap packet window: %v", e) + m, err := memutil.MapFile(0, uintptr(pwd.Length), unix.PROT_READ|unix.PROT_WRITE, unix.MAP_SHARED, uintptr(pwd.FD), uintptr(pwd.Offset)) + if err != nil { + return fmt.Errorf("failed to mmap packet window: %v", err) } ep.packet = m ep.dataCap = uint32(pwd.Length) - uint32(PacketHeaderBytes) @@ -222,6 +223,23 @@ func (ep *Endpoint) RecvFirst() (uint32, error) { // * If ep is a client Endpoint, ep.Connect() has previously been called and // returned nil. func (ep *Endpoint) SendRecv(dataLen uint32) (uint32, error) { + return ep.sendRecv(dataLen, false /* mayRetainP */) +} + +// SendRecvFast is equivalent to SendRecv, but may prevent the caller's runtime +// P from being released, in which case the calling goroutine continues to +// count against GOMAXPROCS while waiting for the peer Endpoint to return +// control to the caller. +// +// SendRecvFast is appropriate if the peer Endpoint is expected to consistently +// return control in a short amount of time (less than ~10ms). +// +// Preconditions: As for SendRecv. +func (ep *Endpoint) SendRecvFast(dataLen uint32) (uint32, error) { + return ep.sendRecv(dataLen, true /* mayRetainP */) +} + +func (ep *Endpoint) sendRecv(dataLen uint32, mayRetainP bool) (uint32, error) { if dataLen > ep.dataCap { panic(fmt.Sprintf("attempting to send packet with datagram length %d (maximum %d)", dataLen, ep.dataCap)) } @@ -232,7 +250,7 @@ func (ep *Endpoint) SendRecv(dataLen uint32) (uint32, error) { // they can only shoot themselves in the foot. *ep.dataLen() = dataLen raceBecomeInactive() - if err := ep.ctrlRoundTrip(); err != nil { + if err := ep.ctrlRoundTrip(mayRetainP); err != nil { return 0, err } raceBecomeActive() |