From 855748030032dc09a054a204ec93f16c91ee1577 Mon Sep 17 00:00:00 2001 From: Brad Beckmann Date: Fri, 20 Aug 2010 11:46:14 -0700 Subject: ruby: Added merge GETS optimization to hammer Added an optimization that merges multiple pending GETS requests into a single request to the owner node. --- src/mem/protocol/MOESI_hammer-dir.sm | 132 +++++++++++++++++++++++++++++++++-- 1 file changed, 125 insertions(+), 7 deletions(-) (limited to 'src/mem/protocol/MOESI_hammer-dir.sm') diff --git a/src/mem/protocol/MOESI_hammer-dir.sm b/src/mem/protocol/MOESI_hammer-dir.sm index 806719916..9f7d08f9d 100644 --- a/src/mem/protocol/MOESI_hammer-dir.sm +++ b/src/mem/protocol/MOESI_hammer-dir.sm @@ -69,6 +69,9 @@ machine(Directory, "AMD Hammer-like protocol") NO_R, desc="Was Not Owner or Sharer, replacing probe filter entry"; NO_B, "NO^B", desc="Not Owner, Blocked"; + NO_B_X, "NO^B", desc="Not Owner, Blocked, next queued request GETX"; + NO_B_S, "NO^B", desc="Not Owner, Blocked, next queued request GETS"; + NO_B_S_W, "NO^B", desc="Not Owner, Blocked, forwarded merged GETS, waiting for responses"; O_B, "O^B", desc="Owner, Blocked"; NO_B_W, desc="Not Owner, Blocked, waiting for Dram"; O_B_W, desc="Owner, Blocked, waiting for Dram"; @@ -121,6 +124,7 @@ machine(Directory, "AMD Hammer-like protocol") All_acks_and_shared_data, desc="Received shared data and message acks"; All_acks_and_owner_data, desc="Received shared data and message acks"; All_acks_and_data_no_sharers, desc="Received all acks and no other processor has a shared copy"; + All_Unblocks, desc="Received all unblocks for a merged gets request"; } // TYPES @@ -148,6 +152,7 @@ machine(Directory, "AMD Hammer-like protocol") DataBlock DataBlk, desc="The current view of system memory"; int Len, desc="..."; MachineID DmaRequestor, desc="DMA requestor"; + NetDest GetSRequestors, desc="GETS merged requestors"; int NumPendingMsgs, desc="Number of pending acks/messages"; bool CacheDirty, default="false", desc="Indicates whether a cache has responded with dirty data"; bool Sharers, default="false", desc="Indicates whether a cache has indicated it is currently a sharer"; @@ -243,6 +248,8 @@ machine(Directory, "AMD Hammer-like protocol") trigger(Event:All_acks_and_shared_data, in_msg.Address); } else if (in_msg.Type == TriggerType:ALL_ACKS_NO_SHARERS) { trigger(Event:All_acks_and_data_no_sharers, in_msg.Address); + } else if (in_msg.Type == TriggerType:ALL_UNBLOCKS) { + trigger(Event:All_Unblocks, in_msg.Address); } else { error("Unexpected message"); } @@ -487,6 +494,20 @@ machine(Directory, "AMD Hammer-like protocol") } } + action(mu_decrementNumberOfUnblocks, "mu", desc="Decrement the number of messages for which we're waiting") { + peek(unblockNetwork_in, ResponseMsg) { + assert(in_msg.Type == CoherenceResponseType:UNBLOCKS); + DEBUG_EXPR(TBEs[address].NumPendingMsgs); + // + // Note that cache data responses will have an ack count of 2. However, + // directory DMA requests must wait for acks from all LLC caches, so + // only decrement by 1. + // + TBEs[address].NumPendingMsgs := TBEs[address].NumPendingMsgs - 1; + DEBUG_EXPR(TBEs[address].NumPendingMsgs); + } + } + action(n_popResponseQueue, "n", desc="Pop response queue") { responseToDir_in.dequeue(); } @@ -508,6 +529,19 @@ machine(Directory, "AMD Hammer-like protocol") } } + action(os_checkForMergedGetSCompletion, "os", desc="Check for merged GETS completion") { + if (TBEs[address].NumPendingMsgs == 0) { + enqueue(triggerQueue_out, TriggerMsg) { + out_msg.Address := address; + out_msg.Type := TriggerType:ALL_UNBLOCKS; + } + } + } + + action(sp_setPendingMsgsToMergedSharers, "sp", desc="Set pending messages to waiting sharers") { + TBEs[address].NumPendingMsgs := TBEs[address].GetSRequestors.count(); + } + action(spa_setPendingAcksToZeroIfPF, "spa", desc="if probe filter, no need to wait for acks") { if (probe_filter_enabled) { TBEs[address].NumPendingMsgs := 0; @@ -598,6 +632,12 @@ machine(Directory, "AMD Hammer-like protocol") } } + action(rs_recordGetSRequestor, "rs", desc="Record GETS requestor in TBE") { + peek(requestQueue_in, RequestMsg) { + TBEs[address].GetSRequestors.add(in_msg.Requestor); + } + } + action(r_setSharerBit, "r", desc="We saw other sharers") { TBEs[address].Sharers := true; } @@ -694,6 +734,29 @@ machine(Directory, "AMD Hammer-like protocol") } } + action(fr_forwardMergeReadRequestsToOwner, "frr", desc="Forward coalesced read request to owner") { + assert(machineCount(MachineType:L1Cache) > 1); + // + // Fixme! The unblock network should not stall on the forward network. Add a trigger queue to + // decouple the two. + // + peek(unblockNetwork_in, ResponseMsg) { + enqueue(forwardNetwork_out, RequestMsg, latency=memory_controller_latency) { + out_msg.Address := address; + out_msg.Type := CoherenceRequestType:MERGED_GETS; + out_msg.MergedRequestors := TBEs[address].GetSRequestors; + if (in_msg.Type == CoherenceResponseType:UNBLOCKS) { + out_msg.Destination.add(in_msg.CurOwner); + } else { + out_msg.Destination.add(in_msg.Sender); + } + out_msg.MessageSize := MessageSizeType:Request_Control; + out_msg.InitialRequestTime := zero_time(); + out_msg.ForwardRequestTime := get_time(); + } + } + } + action(fc_forwardRequestConditionalOwner, "fc", desc="Forward request to one or more nodes") { assert(machineCount(MachineType:L1Cache) > 1); if (probe_filter_enabled) { @@ -1058,31 +1121,81 @@ machine(Directory, "AMD Hammer-like protocol") } // Blocked transient states - transition({NO_B, O_B, NO_DR_B_W, NO_DW_B_W, NO_B_W, NO_DR_B_D, - NO_DR_B, O_DR_B, O_B_W, O_DR_B_W, NO_DW_W, + transition({NO_B_X, O_B, NO_DR_B_W, NO_DW_B_W, NO_B_W, NO_DR_B_D, + NO_DR_B, O_DR_B, O_B_W, O_DR_B_W, NO_DW_W, NO_B_S_W, NO_W, O_W, WB, WB_E_W, WB_O_W, O_R, S_R, NO_R}, {GETS, GETX, PUT, Pf_Replacement}) { z_stallAndWaitRequest; } - transition({NO_B, O_B, NO_DR_B_W, NO_DW_B_W, NO_B_W, NO_DR_B_D, - NO_DR_B, O_DR_B, O_B_W, O_DR_B_W, NO_DW_W, + transition(NO_B, GETX, NO_B_X) { + z_stallAndWaitRequest; + } + + transition(NO_B, {PUT, Pf_Replacement}) { + z_stallAndWaitRequest; + } + + transition(NO_B_S, {GETX, PUT, Pf_Replacement}) { + z_stallAndWaitRequest; + } + + transition({NO_B, NO_B_S, O_B, NO_DR_B_W, NO_DW_B_W, NO_B_W, NO_DR_B_D, + NO_DR_B, O_DR_B, O_B_W, O_DR_B_W, NO_DW_W, NO_B_S_W, NO_W, O_W, WB, WB_E_W, WB_O_W, O_R, S_R, NO_R}, {DMA_READ, DMA_WRITE}) { zd_stallAndWaitDMARequest; } - transition(NO_B, UnblockS, NX) { + // merge GETS into one response + transition(NO_B, GETS, NO_B_S) { + v_allocateTBE; + rs_recordGetSRequestor; + i_popIncomingRequestQueue; + } + + transition(NO_B_S, GETS) { + rs_recordGetSRequestor; + i_popIncomingRequestQueue; + } + + // unblock responses + transition({NO_B, NO_B_X}, UnblockS, NX) { k_wakeUpDependents; j_popIncomingUnblockQueue; } - transition(NO_B, UnblockM, NO) { + transition({NO_B, NO_B_X}, UnblockM, NO) { uo_updateOwnerIfPf; k_wakeUpDependents; j_popIncomingUnblockQueue; } + transition(NO_B_S, UnblockS, NO_B_S_W) { + fr_forwardMergeReadRequestsToOwner; + sp_setPendingMsgsToMergedSharers; + j_popIncomingUnblockQueue; + } + + transition(NO_B_S, UnblockM, NO_B_S_W) { + uo_updateOwnerIfPf; + fr_forwardMergeReadRequestsToOwner; + sp_setPendingMsgsToMergedSharers; + j_popIncomingUnblockQueue; + } + + transition(NO_B_S_W, UnblockS) { + mu_decrementNumberOfUnblocks; + os_checkForMergedGetSCompletion; + j_popIncomingUnblockQueue; + } + + transition(NO_B_S_W, All_Unblocks, NX) { + w_deallocateTBE; + k_wakeUpDependents; + g_popTriggerQueue; + } + transition(O_B, UnblockS, O) { k_wakeUpDependents; j_popIncomingUnblockQueue; @@ -1315,7 +1428,12 @@ machine(Directory, "AMD Hammer-like protocol") l_popMemQueue; } - transition(NO_B_W, {UnblockM, UnblockS}, NO_W) { + transition(NO_B_W, UnblockM, NO_W) { + uo_updateOwnerIfPf; + j_popIncomingUnblockQueue; + } + + transition(NO_B_W, UnblockS, NO_W) { j_popIncomingUnblockQueue; } -- cgit v1.2.3