From 6c312a24b6041385c33eca066ff5604af315a41e Mon Sep 17 00:00:00 2001 From: gary rong Date: Thu, 14 Mar 2019 18:19:03 +0800 Subject: eth/downloader: fix ancestor searching for light syncing (#19136) --- eth/downloader/downloader.go | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go index b8eaa6a5e..d926d7aad 100644 --- a/eth/downloader/downloader.go +++ b/eth/downloader/downloader.go @@ -665,30 +665,32 @@ func (d *Downloader) findAncestor(p *peerConnection, remoteHeader *types.Header) localHeight = d.lightchain.CurrentHeader().Number.Uint64() } p.log.Debug("Looking for common ancestor", "local", localHeight, "remote", remoteHeight) + + // Recap floor value for binary search if localHeight >= MaxForkAncestry { // We're above the max reorg threshold, find the earliest fork point floor = int64(localHeight - MaxForkAncestry) - - // If we're doing a light sync, ensure the floor doesn't go below the CHT, as - // all headers before that point will be missing. - if d.mode == LightSync { - // If we dont know the current CHT position, find it - if d.genesis == 0 { - header := d.lightchain.CurrentHeader() - for header != nil { - d.genesis = header.Number.Uint64() - if floor >= int64(d.genesis)-1 { - break - } - header = d.lightchain.GetHeaderByHash(header.ParentHash) + } + // If we're doing a light sync, ensure the floor doesn't go below the CHT, as + // all headers before that point will be missing. + if d.mode == LightSync { + // If we dont know the current CHT position, find it + if d.genesis == 0 { + header := d.lightchain.CurrentHeader() + for header != nil { + d.genesis = header.Number.Uint64() + if floor >= int64(d.genesis)-1 { + break } - } - // We already know the "genesis" block number, cap floor to that - if floor < int64(d.genesis)-1 { - floor = int64(d.genesis) - 1 + header = d.lightchain.GetHeaderByHash(header.ParentHash) } } + // We already know the "genesis" block number, cap floor to that + if floor < int64(d.genesis)-1 { + floor = int64(d.genesis) - 1 + } } + from, count, skip, max := calculateRequestSpan(remoteHeight, localHeight) p.log.Trace("Span searching for common ancestor", "count", count, "from", from, "skip", skip) -- cgit v1.2.3