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authorTed Yin <[email protected]>2020-09-18 13:14:29 -0400
committerGitHub <[email protected]>2020-09-18 13:14:29 -0400
commitd048937c48753d9eaef771bf71820cf95d79df26 (patch)
tree1a7f65fcd72e77092525ab01625b8b9d365e3e40 /core/headerchain.go
parent7d1388c743b4ec8f4a86bea95bfada785dee83f7 (diff)
parent7d8c85cf8895b0f998d8eafb02f99d5b689fcd59 (diff)
Merge pull request #34 from ava-labs/devv0.3.0-rc.5
Dev
Diffstat (limited to 'core/headerchain.go')
-rw-r--r--core/headerchain.go161
1 files changed, 110 insertions, 51 deletions
diff --git a/core/headerchain.go b/core/headerchain.go
index d956226..20f6bd3 100644
--- a/core/headerchain.go
+++ b/core/headerchain.go
@@ -30,9 +30,9 @@ import (
"github.com/ava-labs/coreth/core/rawdb"
"github.com/ava-labs/coreth/core/types"
"github.com/ava-labs/coreth/params"
- "github.com/ava-labs/go-ethereum/common"
- "github.com/ava-labs/go-ethereum/ethdb"
- "github.com/ava-labs/go-ethereum/log"
+ "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/ethdb"
+ "github.com/ethereum/go-ethereum/log"
lru "github.com/hashicorp/golang-lru"
)
@@ -45,6 +45,14 @@ const (
// HeaderChain implements the basic block header chain logic that is shared by
// core.BlockChain and light.LightChain. It is not usable in itself, only as
// a part of either structure.
+//
+// HeaderChain is responsible for maintaining the header chain including the
+// header query and updating.
+//
+// The components maintained by headerchain includes: (1) total difficult
+// (2) header (3) block hash -> number mapping (4) canonical number -> hash mapping
+// and (5) head header flag.
+//
// It is not thread safe either, the encapsulating chain structures should do
// the necessary mutex locking/unlocking.
type HeaderChain struct {
@@ -66,10 +74,8 @@ type HeaderChain struct {
engine consensus.Engine
}
-// NewHeaderChain creates a new HeaderChain structure.
-// getValidator should return the parent's validator
-// procInterrupt points to the parent's interrupt semaphore
-// wg points to the parent's shutdown wait group
+// NewHeaderChain creates a new HeaderChain structure. ProcInterrupt points
+// to the parent's interrupt semaphore.
func NewHeaderChain(chainDb ethdb.Database, config *params.ChainConfig, engine consensus.Engine, procInterrupt func() bool) (*HeaderChain, error) {
headerCache, _ := lru.New(headerCacheLimit)
tdCache, _ := lru.New(tdCacheLimit)
@@ -143,29 +149,46 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
if ptd == nil {
return NonStatTy, consensus.ErrUnknownAncestor
}
- localTd := hc.GetTd(hc.currentHeaderHash, hc.CurrentHeader().Number.Uint64())
+ head := hc.CurrentHeader().Number.Uint64()
+ localTd := hc.GetTd(hc.currentHeaderHash, head)
externTd := new(big.Int).Add(header.Difficulty, ptd)
// Irrelevant of the canonical status, write the td and header to the database
- if err := hc.WriteTd(hash, number, externTd); err != nil {
- log.Crit("Failed to write header total difficulty", "err", err)
+ //
+ // Note all the components of header(td, hash->number index and header) should
+ // be written atomically.
+ headerBatch := hc.chainDb.NewBatch()
+ rawdb.WriteTd(headerBatch, hash, number, externTd)
+ rawdb.WriteHeader(headerBatch, header)
+ if err := headerBatch.Write(); err != nil {
+ log.Crit("Failed to write header into disk", "err", err)
}
- rawdb.WriteHeader(hc.chainDb, header)
-
// If the total difficulty is higher than our known, add it to the canonical chain
// Second clause in the if statement reduces the vulnerability to selfish mining.
// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
- if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) {
+ reorg := externTd.Cmp(localTd) > 0
+ if !reorg && externTd.Cmp(localTd) == 0 {
+ if header.Number.Uint64() < head {
+ reorg = true
+ } else if header.Number.Uint64() == head {
+ reorg = mrand.Float64() < 0.5
+ }
+ }
+ if reorg {
+ // If the header can be added into canonical chain, adjust the
+ // header chain markers(canonical indexes and head header flag).
+ //
+ // Note all markers should be written atomically.
+
// Delete any canonical number assignments above the new head
- batch := hc.chainDb.NewBatch()
+ markerBatch := hc.chainDb.NewBatch()
for i := number + 1; ; i++ {
hash := rawdb.ReadCanonicalHash(hc.chainDb, i)
if hash == (common.Hash{}) {
break
}
- rawdb.DeleteCanonicalHash(batch, i)
+ rawdb.DeleteCanonicalHash(markerBatch, i)
}
- batch.Write()
// Overwrite any stale canonical number assignments
var (
@@ -174,16 +197,19 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
headHeader = hc.GetHeader(headHash, headNumber)
)
for rawdb.ReadCanonicalHash(hc.chainDb, headNumber) != headHash {
- rawdb.WriteCanonicalHash(hc.chainDb, headHash, headNumber)
+ rawdb.WriteCanonicalHash(markerBatch, headHash, headNumber)
headHash = headHeader.ParentHash
headNumber = headHeader.Number.Uint64() - 1
headHeader = hc.GetHeader(headHash, headNumber)
}
// Extend the canonical chain with the new header
- rawdb.WriteCanonicalHash(hc.chainDb, hash, number)
- rawdb.WriteHeadHeaderHash(hc.chainDb, hash)
-
+ rawdb.WriteCanonicalHash(markerBatch, hash, number)
+ rawdb.WriteHeadHeaderHash(markerBatch, hash)
+ if err := markerBatch.Write(); err != nil {
+ log.Crit("Failed to write header markers into disk", "err", err)
+ }
+ // Last step update all in-memory head header markers
hc.currentHeaderHash = hash
hc.currentHeader.Store(types.CopyHeader(header))
headHeaderGauge.Update(header.Number.Int64())
@@ -192,9 +218,9 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
} else {
status = SideStatTy
}
+ hc.tdCache.Add(hash, externTd)
hc.headerCache.Add(hash, header)
hc.numberCache.Add(hash, number)
-
return
}
@@ -349,8 +375,11 @@ func (hc *HeaderChain) GetAncestor(hash common.Hash, number, ancestor uint64, ma
}
for ancestor != 0 {
if rawdb.ReadCanonicalHash(hc.chainDb, number) == hash {
- number -= ancestor
- return rawdb.ReadCanonicalHash(hc.chainDb, number), number
+ ancestorHash := rawdb.ReadCanonicalHash(hc.chainDb, number-ancestor)
+ if rawdb.ReadCanonicalHash(hc.chainDb, number) == hash {
+ number -= ancestor
+ return ancestorHash, number
+ }
}
if *maxNonCanonical == 0 {
return common.Hash{}, 0
@@ -393,14 +422,6 @@ func (hc *HeaderChain) GetTdByHash(hash common.Hash) *big.Int {
return hc.GetTd(hash, *number)
}
-// WriteTd stores a block's total difficulty into the database, also caching it
-// along the way.
-func (hc *HeaderChain) WriteTd(hash common.Hash, number uint64, td *big.Int) error {
- rawdb.WriteTd(hc.chainDb, hash, number, td)
- hc.tdCache.Add(hash, new(big.Int).Set(td))
- return nil
-}
-
// GetHeader retrieves a block header from the database by hash and number,
// caching it if found.
func (hc *HeaderChain) GetHeader(hash common.Hash, number uint64) *types.Header {
@@ -428,6 +449,8 @@ func (hc *HeaderChain) GetHeaderByHash(hash common.Hash) *types.Header {
}
// HasHeader checks if a block header is present in the database or not.
+// In theory, if header is present in the database, all relative components
+// like td and hash->number should be present too.
func (hc *HeaderChain) HasHeader(hash common.Hash, number uint64) bool {
if hc.numberCache.Contains(hash) || hc.headerCache.Contains(hash) {
return true
@@ -445,16 +468,19 @@ func (hc *HeaderChain) GetHeaderByNumber(number uint64) *types.Header {
return hc.GetHeader(hash, number)
}
+func (hc *HeaderChain) GetCanonicalHash(number uint64) common.Hash {
+ return rawdb.ReadCanonicalHash(hc.chainDb, number)
+}
+
// CurrentHeader retrieves the current head header of the canonical chain. The
// header is retrieved from the HeaderChain's internal cache.
func (hc *HeaderChain) CurrentHeader() *types.Header {
return hc.currentHeader.Load().(*types.Header)
}
-// SetCurrentHeader sets the current head header of the canonical chain.
+// SetCurrentHeader sets the in-memory head header marker of the canonical chan
+// as the given header.
func (hc *HeaderChain) SetCurrentHeader(head *types.Header) {
- rawdb.WriteHeadHeaderHash(hc.chainDb, head.Hash())
-
hc.currentHeader.Store(head)
hc.currentHeaderHash = head.Hash()
headHeaderGauge.Update(head.Number.Int64())
@@ -462,8 +488,10 @@ func (hc *HeaderChain) SetCurrentHeader(head *types.Header) {
type (
// UpdateHeadBlocksCallback is a callback function that is called by SetHead
- // before head header is updated.
- UpdateHeadBlocksCallback func(ethdb.KeyValueWriter, *types.Header)
+ // before head header is updated. The method will return the actual block it
+ // updated the head to (missing state) and a flag if setHead should continue
+ // rewinding till that forcefully (exceeded ancient limits)
+ UpdateHeadBlocksCallback func(ethdb.KeyValueWriter, *types.Header) (uint64, bool)
// DeleteBlockContentCallback is a callback function that is called by SetHead
// before each header is deleted.
@@ -476,9 +504,10 @@ func (hc *HeaderChain) SetHead(head uint64, updateFn UpdateHeadBlocksCallback, d
var (
parentHash common.Hash
batch = hc.chainDb.NewBatch()
+ origin = true
)
for hdr := hc.CurrentHeader(); hdr != nil && hdr.Number.Uint64() > head; hdr = hc.CurrentHeader() {
- hash, num := hdr.Hash(), hdr.Number.Uint64()
+ num := hdr.Number.Uint64()
// Rewind block chain to new head.
parent := hc.GetHeader(hdr.ParentHash, num-1)
@@ -486,34 +515,64 @@ func (hc *HeaderChain) SetHead(head uint64, updateFn UpdateHeadBlocksCallback, d
parent = hc.genesisHeader
}
parentHash = hdr.ParentHash
+
// Notably, since geth has the possibility for setting the head to a low
// height which is even lower than ancient head.
// In order to ensure that the head is always no higher than the data in
- // the database(ancient store or active store), we need to update head
+ // the database (ancient store or active store), we need to update head
// first then remove the relative data from the database.
//
// Update head first(head fast block, head full block) before deleting the data.
+ markerBatch := hc.chainDb.NewBatch()
if updateFn != nil {
- updateFn(hc.chainDb, parent)
+ newHead, force := updateFn(markerBatch, parent)
+ if force && newHead < head {
+ log.Warn("Force rewinding till ancient limit", "head", newHead)
+ head = newHead
+ }
}
// Update head header then.
- rawdb.WriteHeadHeaderHash(hc.chainDb, parentHash)
-
- // Remove the relative data from the database.
- if delFn != nil {
- delFn(batch, hash, num)
+ rawdb.WriteHeadHeaderHash(markerBatch, parentHash)
+ if err := markerBatch.Write(); err != nil {
+ log.Crit("Failed to update chain markers", "error", err)
}
- // Rewind header chain to new head.
- rawdb.DeleteHeader(batch, hash, num)
- rawdb.DeleteTd(batch, hash, num)
- rawdb.DeleteCanonicalHash(batch, num)
-
hc.currentHeader.Store(parent)
hc.currentHeaderHash = parentHash
headHeaderGauge.Update(parent.Number.Int64())
- }
- batch.Write()
+ // If this is the first iteration, wipe any leftover data upwards too so
+ // we don't end up with dangling daps in the database
+ var nums []uint64
+ if origin {
+ for n := num + 1; len(rawdb.ReadAllHashes(hc.chainDb, n)) > 0; n++ {
+ nums = append([]uint64{n}, nums...) // suboptimal, but we don't really expect this path
+ }
+ origin = false
+ }
+ nums = append(nums, num)
+
+ // Remove the related data from the database on all sidechains
+ for _, num := range nums {
+ // Gather all the side fork hashes
+ hashes := rawdb.ReadAllHashes(hc.chainDb, num)
+ if len(hashes) == 0 {
+ // No hashes in the database whatsoever, probably frozen already
+ hashes = append(hashes, hdr.Hash())
+ }
+ for _, hash := range hashes {
+ if delFn != nil {
+ delFn(batch, hash, num)
+ }
+ rawdb.DeleteHeader(batch, hash, num)
+ rawdb.DeleteTd(batch, hash, num)
+ }
+ rawdb.DeleteCanonicalHash(batch, num)
+ }
+ }
+ // Flush all accumulated deletions.
+ if err := batch.Write(); err != nil {
+ log.Crit("Failed to rewind block", "error", err)
+ }
// Clear out any stale content from the caches
hc.headerCache.Purge()
hc.tdCache.Purge()