Mercurial > hg > bitcoin
changeset 935:189ccb63b08b draft
Merge pull request #500 from gavinandresen/txndeadlock
Fix AddAddress cs_mapaddresses/db transaction deadlock
author | Gavin Andresen <gavinandresen@gmail.com> |
---|---|
date | Wed, 07 Sep 2011 07:29:44 -0700 |
parents | b85b74cbbad6 (current diff) a99cda147efc (diff) |
children | 4f02348aa51e faf2e7658d0c 7309d19d9ef3 e5d23800c530 bb5150a11d8b |
files | |
diffstat | 1 files changed, 21 insertions(+), 15 deletions(-) [+] |
line wrap: on
line diff
--- a/src/net.cpp +++ b/src/net.cpp @@ -443,6 +443,10 @@ if (addr.ip == addrLocalHost.ip) return false; addr.nTime = max((int64)0, (int64)addr.nTime - nTimePenalty); + bool fUpdated = false; + bool fNew = false; + CAddress addrFound = addr; + CRITICAL_BLOCK(cs_mapAddresses) { map<vector<unsigned char>, CAddress>::iterator it = mapAddresses.find(addr.GetKey()); @@ -451,16 +455,12 @@ // New address printf("AddAddress(%s)\n", addr.ToString().c_str()); mapAddresses.insert(make_pair(addr.GetKey(), addr)); - if (pAddrDB) - pAddrDB->WriteAddress(addr); - else - CAddrDB().WriteAddress(addr); - return true; + fUpdated = true; + fNew = true; } else { - bool fUpdated = false; - CAddress& addrFound = (*it).second; + addrFound = (*it).second; if ((addrFound.nServices | addr.nServices) != addrFound.nServices) { // Services have been added @@ -475,16 +475,22 @@ addrFound.nTime = addr.nTime; fUpdated = true; } - if (fUpdated) - { - if (pAddrDB) - pAddrDB->WriteAddress(addrFound); - else - CAddrDB().WriteAddress(addrFound); - } } } - return false; + // There is a nasty deadlock bug if this is done inside the cs_mapAddresses + // CRITICAL_BLOCK: + // Thread 1: begin db transaction (locks inside-db-mutex) + // then AddAddress (locks cs_mapAddresses) + // Thread 2: AddAddress (locks cs_mapAddresses) + // ... then db operation hangs waiting for inside-db-mutex + if (fUpdated) + { + if (pAddrDB) + pAddrDB->WriteAddress(addrFound); + else + CAddrDB().WriteAddress(addrFound); + } + return fNew; } void AddressCurrentlyConnected(const CAddress& addr)