eth: fix data race accessing peer.td

This commit is contained in:
Péter Szilágyi 2015-06-09 14:56:27 +03:00
parent 44147d057d
commit f86707713c
3 changed files with 33 additions and 14 deletions

View File

@ -356,7 +356,7 @@ func (pm *ProtocolManager) importBlock(p *peer, block *types.Block, td *big.Int)
p.blockHashes.Add(hash)
p.SetHead(hash)
if td != nil {
p.td = td
p.SetTd(td)
}
// Log the block's arrival
_, chainHead, _ := pm.chainman.Status()
@ -369,7 +369,7 @@ func (pm *ProtocolManager) importBlock(p *peer, block *types.Block, td *big.Int)
})
// If the block's already known or its difficulty is lower than ours, drop
if pm.chainman.HasBlock(hash) {
p.td = pm.chainman.GetBlock(hash).Td // update the peer's TD to the real value
p.SetTd(pm.chainman.GetBlock(hash).Td) // update the peer's TD to the real value
return nil
}
if td != nil && pm.chainman.Td().Cmp(td) > 0 && new(big.Int).Add(block.Number(), big.NewInt(7)).Cmp(pm.chainman.CurrentBlock().Number()) < 0 {

View File

@ -41,10 +41,10 @@ type peer struct {
protv, netid int
id string
td *big.Int
head common.Hash
headLock sync.RWMutex
head common.Hash
td *big.Int
lock sync.RWMutex
genesis, ourHash common.Hash
ourTd *big.Int
@ -72,8 +72,8 @@ func newPeer(protv, netid int, genesis, head common.Hash, td *big.Int, p *p2p.Pe
// Head retrieves a copy of the current head (most recent) hash of the peer.
func (p *peer) Head() (hash common.Hash) {
p.headLock.RLock()
defer p.headLock.RUnlock()
p.lock.RLock()
defer p.lock.RUnlock()
copy(hash[:], p.head[:])
return hash
@ -81,12 +81,28 @@ func (p *peer) Head() (hash common.Hash) {
// SetHead updates the head (most recent) hash of the peer.
func (p *peer) SetHead(hash common.Hash) {
p.headLock.Lock()
defer p.headLock.Unlock()
p.lock.Lock()
defer p.lock.Unlock()
copy(p.head[:], hash[:])
}
// Td retrieves the current total difficulty of a peer.
func (p *peer) Td() *big.Int {
p.lock.RLock()
defer p.lock.RUnlock()
return new(big.Int).Set(p.td)
}
// SetTd updates the current total difficulty of a peer.
func (p *peer) SetTd(td *big.Int) {
p.lock.Lock()
defer p.lock.Unlock()
p.td.Set(td)
}
// sendTransactions sends transactions to the peer and includes the hashes
// in it's tx hash set for future reference. The tx hash will allow the
// manager to check whether the peer has already received this particular
@ -275,11 +291,14 @@ func (ps *peerSet) BestPeer() *peer {
ps.lock.RLock()
defer ps.lock.RUnlock()
var best *peer
var (
bestPeer *peer
bestTd *big.Int
)
for _, p := range ps.peers {
if best == nil || p.td.Cmp(best.td) > 0 {
best = p
if td := p.Td(); bestPeer == nil || td.Cmp(bestTd) > 0 {
bestPeer, bestTd = p, td
}
}
return best
return bestPeer
}

View File

@ -208,7 +208,7 @@ func (pm *ProtocolManager) synchronise(peer *peer) {
return
}
// Make sure the peer's TD is higher than our own. If not drop.
if peer.td.Cmp(pm.chainman.Td()) <= 0 {
if peer.Td().Cmp(pm.chainman.Td()) <= 0 {
return
}
// FIXME if we have the hash in our chain and the TD of the peer is