Fix locking in getConnection #288
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Signed-off-by: Henry Robinson <[email protected]>
Signed-off-by: Henry Robinson <[email protected]>
Signed-off-by: Henry Robinson <[email protected]>
| proxy.mu.Lock() | ||
| defer proxy.mu.Unlock() |
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Oops much better thanks.
But I think we still need the RUnlock() because IIRC you can't "promote" a RWLock without first dropping the read lock.
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I think it's still there - just moved above the log / error checking logic.
| grpcclient.RegisterGRPCDialOptions(func(opts []grpc.DialOption) ([]grpc.DialOption, error) { | ||
| return append(opts, grpc.WithDefaultServiceConfig(`{"loadBalancingConfig": [{"round_robin":{}}]}`)), nil | ||
| }) | ||
| // Check again in case conn was made between lock acquisitions. |
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Also very good idea, thanks.
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| // Otherwise create a new connection. TODO: confirm this doesn't actually make a TCP connection, and returns quickly, |
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For sure it does not. There's a WithBlock thing that IIRC you can pass to make this blocking, but if not then it is non-blocking.
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Ya - confirmed, the model in grpc is pretty weird, you create a "conn", but that's basically just a handle to make RPC requests. It's not until you make an RPC call that it will actually start mapping the RPC to a subconn (which maps to a TCP connection).
That's also why you can reuse the conn - it should represent a logical target to send the RPC commands to.
| @@ -174,4 +179,8 @@ func (proxy *VTGateProxy) StreamExecute(ctx context.Context, session *vtgateconn | |||
| } | |||
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| func Init() { | |||
| log.V(100).Infof("Registering GRPC dial options") | |||
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eek - I think demmer and I talked about this and never fixed it - thank you for moving this here and doing it once!
* Fix locking in getConnection Signed-off-by: Henry Robinson <[email protected]> * Comment Signed-off-by: Henry Robinson <[email protected]> * Undo bash change Signed-off-by: Henry Robinson <[email protected]> --------- Signed-off-by: Henry Robinson <[email protected]>
* Fix locking in getConnection Signed-off-by: Henry Robinson <[email protected]> * Comment Signed-off-by: Henry Robinson <[email protected]> * Undo bash change Signed-off-by: Henry Robinson <[email protected]> --------- Signed-off-by: Henry Robinson <[email protected]>
* Fix locking in getConnection Signed-off-by: Henry Robinson <[email protected]> * Comment Signed-off-by: Henry Robinson <[email protected]> * Undo bash change Signed-off-by: Henry Robinson <[email protected]> --------- Signed-off-by: Henry Robinson <[email protected]>
* Fix locking in getConnection Signed-off-by: Henry Robinson <[email protected]> * Comment Signed-off-by: Henry Robinson <[email protected]> * Undo bash change Signed-off-by: Henry Robinson <[email protected]> --------- Signed-off-by: Henry Robinson <[email protected]>
Unlockif an error happens when creating a connection