FedP2P/requesting.go

300 lines
8.3 KiB
Go

package torrent
import (
"container/heap"
"context"
"encoding/gob"
"reflect"
"runtime/pprof"
"time"
"unsafe"
"github.com/RoaringBitmap/roaring"
"github.com/anacrolix/log"
"github.com/anacrolix/multiless"
request_strategy "github.com/anacrolix/torrent/request-strategy"
)
func (cl *Client) tickleRequester() {
cl.updateRequests.Broadcast()
}
func (cl *Client) getRequestStrategyInput() request_strategy.Input {
ts := make([]request_strategy.Torrent, 0, len(cl.torrents))
for _, t := range cl.torrents {
if !t.haveInfo() {
// This would be removed if metadata is handled here. We have to guard against not
// knowing the piece size. If we have no info, we have no pieces too, so the end result
// is the same.
continue
}
rst := request_strategy.Torrent{
InfoHash: t.infoHash,
ChunksPerPiece: t.chunksPerRegularPiece(),
}
if t.storage != nil {
rst.Capacity = t.storage.Capacity
}
rst.Pieces = make([]request_strategy.Piece, 0, len(t.pieces))
for i := range t.pieces {
p := &t.pieces[i]
rst.Pieces = append(rst.Pieces, request_strategy.Piece{
Request: !t.ignorePieceForRequests(i),
Priority: p.purePriority(),
Partial: t.piecePartiallyDownloaded(i),
Availability: p.availability,
Length: int64(p.length()),
NumPendingChunks: int(t.pieceNumPendingChunks(i)),
IterPendingChunks: &p.undirtiedChunksIter,
})
}
t.iterPeers(func(p *Peer) {
if p.closed.IsSet() {
return
}
if p.piecesReceivedSinceLastRequestUpdate > p.maxPiecesReceivedBetweenRequestUpdates {
p.maxPiecesReceivedBetweenRequestUpdates = p.piecesReceivedSinceLastRequestUpdate
}
p.piecesReceivedSinceLastRequestUpdate = 0
rst.Peers = append(rst.Peers, request_strategy.Peer{
Pieces: *p.newPeerPieces(),
MaxRequests: p.nominalMaxRequests(),
ExistingRequests: p.actualRequestState.Requests,
Choking: p.peerChoking,
PieceAllowedFast: p.peerAllowedFast,
DownloadRate: p.downloadRate(),
Age: time.Since(p.completedHandshake),
Id: peerId{
Peer: p,
ptr: uintptr(unsafe.Pointer(p)),
},
})
})
ts = append(ts, rst)
}
return request_strategy.Input{
Torrents: ts,
MaxUnverifiedBytes: cl.config.MaxUnverifiedBytes,
}
}
func init() {
gob.Register(peerId{})
}
type peerId struct {
*Peer
ptr uintptr
}
func (p peerId) Uintptr() uintptr {
return p.ptr
}
func (p peerId) GobEncode() (b []byte, _ error) {
*(*reflect.SliceHeader)(unsafe.Pointer(&b)) = reflect.SliceHeader{
Data: uintptr(unsafe.Pointer(&p.ptr)),
Len: int(unsafe.Sizeof(p.ptr)),
Cap: int(unsafe.Sizeof(p.ptr)),
}
return
}
func (p *peerId) GobDecode(b []byte) error {
if uintptr(len(b)) != unsafe.Sizeof(p.ptr) {
panic(len(b))
}
ptr := unsafe.Pointer(&b[0])
p.ptr = *(*uintptr)(ptr)
log.Printf("%p", ptr)
dst := reflect.SliceHeader{
Data: uintptr(unsafe.Pointer(&p.Peer)),
Len: int(unsafe.Sizeof(p.Peer)),
Cap: int(unsafe.Sizeof(p.Peer)),
}
copy(*(*[]byte)(unsafe.Pointer(&dst)), b)
return nil
}
type RequestIndex = request_strategy.RequestIndex
type chunkIndexType = request_strategy.ChunkIndex
type peerRequests struct {
requestIndexes []RequestIndex
peer *Peer
torrentStrategyInput request_strategy.Torrent
}
func (p *peerRequests) Len() int {
return len(p.requestIndexes)
}
func (p *peerRequests) Less(i, j int) bool {
leftRequest := p.requestIndexes[i]
rightRequest := p.requestIndexes[j]
t := p.peer.t
leftPieceIndex := leftRequest / p.torrentStrategyInput.ChunksPerPiece
rightPieceIndex := rightRequest / p.torrentStrategyInput.ChunksPerPiece
leftCurrent := p.peer.actualRequestState.Requests.Contains(leftRequest)
rightCurrent := p.peer.actualRequestState.Requests.Contains(rightRequest)
pending := func(index RequestIndex, current bool) int {
ret := t.pendingRequests.Get(index)
if current {
ret--
}
// I have a hunch that this could trigger for requests for chunks that are choked and not
// allowed fast, since the current conn shouldn't already be included. It's a very specific
// circumstance, and if it triggers I will fix it.
if ret < 0 {
panic(ret)
}
return ret
}
ml := multiless.New()
// Push requests that can't be served right now to the end. But we don't throw them away unless
// there's a better alternative. This is for when we're using the fast extension and get choked
// but our requests could still be good when we get unchoked.
if p.peer.peerChoking {
ml = ml.Bool(
!p.peer.peerAllowedFast.Contains(leftPieceIndex),
!p.peer.peerAllowedFast.Contains(rightPieceIndex),
)
}
ml = ml.Int(
pending(leftRequest, leftCurrent),
pending(rightRequest, rightCurrent))
ml = ml.Bool(!leftCurrent, !rightCurrent)
ml = ml.Int(
-int(p.torrentStrategyInput.Pieces[leftPieceIndex].Priority),
-int(p.torrentStrategyInput.Pieces[rightPieceIndex].Priority),
)
ml = ml.Int(
int(p.torrentStrategyInput.Pieces[leftPieceIndex].Availability),
int(p.torrentStrategyInput.Pieces[rightPieceIndex].Availability))
ml = ml.Uint32(leftPieceIndex, rightPieceIndex)
ml = ml.Uint32(leftRequest, rightRequest)
return ml.MustLess()
}
func (p *peerRequests) Swap(i, j int) {
p.requestIndexes[i], p.requestIndexes[j] = p.requestIndexes[j], p.requestIndexes[i]
}
func (p *peerRequests) Push(x interface{}) {
p.requestIndexes = append(p.requestIndexes, x.(RequestIndex))
}
func (p *peerRequests) Pop() interface{} {
last := len(p.requestIndexes) - 1
x := p.requestIndexes[last]
p.requestIndexes = p.requestIndexes[:last]
return x
}
func (p *Peer) getDesiredRequestState() (desired requestState) {
input := p.t.cl.getRequestStrategyInput()
requestHeap := peerRequests{
peer: p,
}
for _, t := range input.Torrents {
if t.InfoHash == p.t.infoHash {
requestHeap.torrentStrategyInput = t
break
}
}
request_strategy.GetRequestablePieces(
input,
func(t *request_strategy.Torrent, rsp *request_strategy.Piece, pieceIndex int) {
if t.InfoHash != p.t.infoHash {
return
}
if !p.peerHasPiece(pieceIndex) {
return
}
allowedFast := p.peerAllowedFast.ContainsInt(pieceIndex)
rsp.IterPendingChunks.Iter(func(ci request_strategy.ChunkIndex) {
if !allowedFast {
// We must signal interest to request this..
desired.Interested = true
if p.peerChoking && !p.actualRequestState.Requests.Contains(ci) {
// We can't request this right now.
return
}
}
requestHeap.requestIndexes = append(
requestHeap.requestIndexes,
p.t.pieceRequestIndexOffset(pieceIndex)+ci)
})
},
)
heap.Init(&requestHeap)
for requestHeap.Len() != 0 && desired.Requests.GetCardinality() < uint64(p.nominalMaxRequests()) {
requestIndex := heap.Pop(&requestHeap).(RequestIndex)
desired.Requests.Add(requestIndex)
}
return
}
func (p *Peer) applyNextRequestState() bool {
if p.needRequestUpdate == "" {
return true
}
var more bool
pprof.Do(
context.Background(),
pprof.Labels("update request", p.needRequestUpdate),
func(_ context.Context) {
next := p.getDesiredRequestState()
more = p.applyRequestState(next)
},
)
return more
}
func (p *Peer) applyRequestState(next requestState) bool {
current := &p.actualRequestState
if !p.setInterested(next.Interested) {
return false
}
more := true
cancel := roaring.AndNot(&current.Requests, &next.Requests)
cancel.Iterate(func(req uint32) bool {
more = p.cancel(req)
return more
})
if !more {
return false
}
next.Requests.Iterate(func(req uint32) bool {
if p.cancelledRequests.Contains(req) {
// Waiting for a reject or piece message, which will suitably trigger us to update our
// requests, so we can skip this one with no additional consideration.
return true
}
if maxRequests(current.Requests.GetCardinality()) >= p.nominalMaxRequests() {
//log.Printf("not assigning all requests [desired=%v, cancelled=%v, current=%v, max=%v]",
// next.Requests.GetCardinality(),
// p.cancelledRequests.GetCardinality(),
// current.Requests.GetCardinality(),
// p.nominalMaxRequests(),
//)
return false
}
var err error
more, err = p.request(req)
if err != nil {
panic(err)
}
return more
})
p.updateRequestsTimer.Stop()
if more {
p.needRequestUpdate = ""
if !current.Requests.IsEmpty() {
p.updateRequestsTimer.Reset(time.Second)
}
}
return more
}