From 8daad28a90ff8ec7044f9c40f0583387cef71792 Mon Sep 17 00:00:00 2001 From: Brad Beckmann Date: Thu, 1 Dec 2011 10:08:52 -0800 Subject: MOESI_hammer: fixed L2 to L1 infinite stalls and deadlock --HG-- extra : rebase_source : 90f217f28e195a8cee5d64b25c913b452d818676 --- src/mem/protocol/MOESI_hammer-cache.sm | 66 +++++++++++++++++++++++----------- 1 file changed, 46 insertions(+), 20 deletions(-) (limited to 'src/mem/protocol/MOESI_hammer-cache.sm') diff --git a/src/mem/protocol/MOESI_hammer-cache.sm b/src/mem/protocol/MOESI_hammer-cache.sm index 9576ba1af..b9d355736 100644 --- a/src/mem/protocol/MOESI_hammer-cache.sm +++ b/src/mem/protocol/MOESI_hammer-cache.sm @@ -62,6 +62,13 @@ machine(L1Cache, "AMD Hammer-like protocol") M, AccessPermission:Read_Only, desc="Modified (dirty)"; MM, AccessPermission:Read_Write, desc="Modified (dirty and locally modified)"; + // Base states, locked and ready to service the mandatory queue + IR, AccessPermission:Invalid, desc="Idle"; + SR, AccessPermission:Read_Only, desc="Shared"; + OR, AccessPermission:Read_Only, desc="Owned"; + MR, AccessPermission:Read_Only, desc="Modified (dirty)"; + MMR, AccessPermission:Read_Write, desc="Modified (dirty and locally modified)"; + // Transient States IM, AccessPermission:Busy, "IM", desc="Issued GetX"; SM, AccessPermission:Read_Only, "SM", desc="Issued GetX, we still have a valid copy of the line"; @@ -1217,6 +1224,11 @@ machine(L1Cache, "AMD Hammer-like protocol") stall_and_wait(mandatoryQueue_in, address); } + action(z_stall, "z", desc="stall") { + // do nothing and the special z_stall action will return a protocol stall + // so that the next port is checked + } + action(kd_wakeUpDependents, "kd", desc="wake-up dependents") { wakeUpBuffers(address); } @@ -1246,7 +1258,7 @@ machine(L1Cache, "AMD Hammer-like protocol") zz_stallAndWaitMandatoryQueue; } - transition({IM, SM, ISM, OM, IS, SS, MM_W, M_W, OI, MI, II, IT, ST, OT, MT, MMT, IM_F, SM_F, ISM_F, OM_F, MM_WF, MI_F, MM_F}, L1_to_L2) { + transition({IM, SM, ISM, OM, IS, SS, MM_W, M_W, OI, MI, II, IT, ST, OT, MT, MMT, IM_F, SM_F, ISM_F, OM_F, MM_WF, MI_F, MM_F, IR, SR, OR, MR, MMR}, L1_to_L2) { zz_stallAndWaitMandatoryQueue; } @@ -1259,7 +1271,11 @@ machine(L1Cache, "AMD Hammer-like protocol") } transition({IT, ST, OT, MT, MMT}, {Other_GETX, NC_DMA_GETS, Other_GETS, Merged_GETS, Other_GETS_No_Mig, Invalidate, Flush_line}) { - // stall + z_stall; + } + + transition({IR, SR, OR, MR, MMR}, {Other_GETX, NC_DMA_GETS, Other_GETS, Merged_GETS, Other_GETS_No_Mig, Invalidate}) { + z_stall; } // Transitions moving data between the L1 and L2 caches @@ -1382,33 +1398,33 @@ machine(L1Cache, "AMD Hammer-like protocol") ll_L2toL1Transfer; } - transition(IT, Complete_L2_to_L1, I) { + transition(IT, Complete_L2_to_L1, IR) { j_popTriggerQueue; kd_wakeUpDependents; } - transition(ST, Complete_L2_to_L1, S) { + transition(ST, Complete_L2_to_L1, SR) { j_popTriggerQueue; kd_wakeUpDependents; } - transition(OT, Complete_L2_to_L1, O) { + transition(OT, Complete_L2_to_L1, OR) { j_popTriggerQueue; kd_wakeUpDependents; } - transition(MT, Complete_L2_to_L1, M) { + transition(MT, Complete_L2_to_L1, MR) { j_popTriggerQueue; kd_wakeUpDependents; } - transition(MMT, Complete_L2_to_L1, MM) { + transition(MMT, Complete_L2_to_L1, MMR) { j_popTriggerQueue; kd_wakeUpDependents; } // Transitions from Idle - transition(I, Load, IS) { + transition({I, IR}, Load, IS) { ii_allocateL1DCacheBlock; i_allocateTBE; a_issueGETS; @@ -1416,7 +1432,7 @@ machine(L1Cache, "AMD Hammer-like protocol") k_popMandatoryQueue; } - transition(I, Ifetch, IS) { + transition({I, IR}, Ifetch, IS) { jj_allocateL1ICacheBlock; i_allocateTBE; a_issueGETS; @@ -1424,7 +1440,7 @@ machine(L1Cache, "AMD Hammer-like protocol") k_popMandatoryQueue; } - transition(I, Store, IM) { + transition({I, IR}, Store, IM) { ii_allocateL1DCacheBlock; i_allocateTBE; b_issueGETX; @@ -1432,7 +1448,7 @@ machine(L1Cache, "AMD Hammer-like protocol") k_popMandatoryQueue; } - transition(I, Flush_line, IM_F) { + transition({I, IR}, Flush_line, IM_F) { it_allocateTBE; bf_issueGETF; uu_profileMiss; @@ -1455,14 +1471,19 @@ machine(L1Cache, "AMD Hammer-like protocol") k_popMandatoryQueue; } - transition(S, Store, SM) { + transition(SR, {Load, Ifetch}, S) { + h_load_hit; + k_popMandatoryQueue; + } + + transition({S, SR}, Store, SM) { i_allocateTBE; b_issueGETX; uu_profileMiss; k_popMandatoryQueue; } - transition(S, Flush_line, SM_F) { + transition({S, SR}, Flush_line, SM_F) { i_allocateTBE; bf_issueGETF; uu_profileMiss; @@ -1491,14 +1512,19 @@ machine(L1Cache, "AMD Hammer-like protocol") k_popMandatoryQueue; } - transition(O, Store, OM) { + transition(OR, {Load, Ifetch}, O) { + h_load_hit; + k_popMandatoryQueue; + } + + transition({O, OR}, Store, OM) { i_allocateTBE; b_issueGETX; p_decrementNumberOfMessagesByOne; uu_profileMiss; k_popMandatoryQueue; } - transition(O, Flush_line, OM_F) { + transition({O, OR}, Flush_line, OM_F) { i_allocateTBE; bf_issueGETF; p_decrementNumberOfMessagesByOne; @@ -1530,17 +1556,17 @@ machine(L1Cache, "AMD Hammer-like protocol") } // Transitions from Modified - transition(MM, {Load, Ifetch}) { + transition({MM, MMR}, {Load, Ifetch}, MM) { h_load_hit; k_popMandatoryQueue; } - transition(MM, Store) { + transition({MM, MMR}, Store, MM) { hh_store_hit; k_popMandatoryQueue; } - transition({MM, M}, Flush_line, MM_F) { + transition({MM, M, MMR}, Flush_line, MM_F) { i_allocateTBE; bf_issueGETF; p_decrementNumberOfMessagesByOne; @@ -1587,12 +1613,12 @@ machine(L1Cache, "AMD Hammer-like protocol") } // Transitions from Dirty Exclusive - transition(M, {Load, Ifetch}) { + transition({M, MR}, {Load, Ifetch}, M) { h_load_hit; k_popMandatoryQueue; } - transition(M, Store, MM) { + transition({M, MR}, Store, MM) { hh_store_hit; k_popMandatoryQueue; } -- cgit v1.2.3