lotus/chain/events/events_height.go
Jakub Sztandera 008a2969b2
Fix two races in events
Also race fix: depends on https://github.com/ipfs/go-blockservice/pull/65
Resolves #2092, #2099, #2108, #1930, #2110

Signed-off-by: Jakub Sztandera <kubuxu@protocol.ai>
2020-06-24 17:05:24 +02:00

201 lines
4.1 KiB
Go

package events
import (
"context"
"sync"
"github.com/filecoin-project/specs-actors/actors/abi"
"go.opencensus.io/trace"
"github.com/filecoin-project/lotus/chain/types"
)
type heightEvents struct {
lk sync.Mutex
tsc *tipSetCache
gcConfidence abi.ChainEpoch
ctr triggerID
heightTriggers map[triggerID]*heightHandler
htTriggerHeights map[triggerH][]triggerID
htHeights map[msgH][]triggerID
ctx context.Context
}
func (e *heightEvents) headChangeAt(rev, app []*types.TipSet) error {
ctx, span := trace.StartSpan(e.ctx, "events.HeightHeadChange")
defer span.End()
span.AddAttributes(trace.Int64Attribute("endHeight", int64(app[0].Height())))
span.AddAttributes(trace.Int64Attribute("reverts", int64(len(rev))))
span.AddAttributes(trace.Int64Attribute("applies", int64(len(app))))
e.lk.Lock()
defer e.lk.Unlock()
for _, ts := range rev {
// TODO: log error if h below gcconfidence
// revert height-based triggers
revert := func(h abi.ChainEpoch, ts *types.TipSet) {
for _, tid := range e.htHeights[h] {
ctx, span := trace.StartSpan(ctx, "events.HeightRevert")
rev := e.heightTriggers[tid].revert
e.lk.Unlock()
err := rev(ctx, ts)
e.lk.Lock()
e.heightTriggers[tid].called = false
span.End()
if err != nil {
log.Errorf("reverting chain trigger (@H %d): %s", h, err)
}
}
}
revert(ts.Height(), ts)
subh := ts.Height() - 1
for {
cts, err := e.tsc.get(subh)
if err != nil {
return err
}
if cts != nil {
break
}
revert(subh, ts)
subh--
}
if err := e.tsc.revert(ts); err != nil {
return err
}
}
for i := range app {
ts := app[i]
if err := e.tsc.add(ts); err != nil {
return err
}
// height triggers
apply := func(h abi.ChainEpoch, ts *types.TipSet) error {
for _, tid := range e.htTriggerHeights[h] {
hnd := e.heightTriggers[tid]
if hnd.called {
return nil
}
hnd.called = true
triggerH := h - abi.ChainEpoch(hnd.confidence)
incTs, err := e.tsc.getNonNull(triggerH)
if err != nil {
return err
}
ctx, span := trace.StartSpan(ctx, "events.HeightApply")
span.AddAttributes(trace.BoolAttribute("immediate", false))
handle := hnd.handle
e.lk.Unlock()
err = handle(ctx, incTs, h)
e.lk.Lock()
span.End()
if err != nil {
log.Errorf("chain trigger (@H %d, called @ %d) failed: %+v", triggerH, ts.Height(), err)
}
}
return nil
}
if err := apply(ts.Height(), ts); err != nil {
return err
}
subh := ts.Height() - 1
for {
cts, err := e.tsc.get(subh)
if err != nil {
return err
}
if cts != nil {
break
}
if err := apply(subh, ts); err != nil {
return err
}
subh--
}
}
return nil
}
// ChainAt invokes the specified `HeightHandler` when the chain reaches the
// specified height+confidence threshold. If the chain is rolled-back under the
// specified height, `RevertHandler` will be called.
//
// ts passed to handlers is the tipset at the specified, or above, if lower tipsets were null
func (e *heightEvents) ChainAt(hnd HeightHandler, rev RevertHandler, confidence int, h abi.ChainEpoch) error {
e.lk.Lock() // Tricky locking, check your locks if you modify this function!
bestH := e.tsc.best().Height()
if bestH >= h+abi.ChainEpoch(confidence) {
ts, err := e.tsc.getNonNull(h)
if err != nil {
log.Warnf("events.ChainAt: calling HandleFunc with nil tipset, not found in cache: %s", err)
}
e.lk.Unlock()
ctx, span := trace.StartSpan(e.ctx, "events.HeightApply")
span.AddAttributes(trace.BoolAttribute("immediate", true))
err = hnd(ctx, ts, bestH)
span.End()
if err != nil {
return err
}
e.lk.Lock()
bestH = e.tsc.best().Height()
}
defer e.lk.Unlock()
if bestH >= h+abi.ChainEpoch(confidence)+e.gcConfidence {
return nil
}
triggerAt := h + abi.ChainEpoch(confidence)
id := e.ctr
e.ctr++
e.heightTriggers[id] = &heightHandler{
confidence: confidence,
handle: hnd,
revert: rev,
}
e.htHeights[h] = append(e.htHeights[h], id)
e.htTriggerHeights[triggerAt] = append(e.htTriggerHeights[triggerAt], id)
return nil
}