From: Andreas Hansson Date: Fri, 6 Nov 2015 08:26:33 +0000 (-0500) Subject: mem: Do not treat CleanEvict as a write operation X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8e55d51aaa71d71c7058e8ee15c89d3482991ba2;p=gem5.git mem: Do not treat CleanEvict as a write operation This patch changes the CleanEvict command type to not be considered a write. Initially it was made a zero-sized write to match the writeback command, but as things developed it became clear that it causes more problems than it solves. For example, the memory modules (and bridge) should not consider the CleanEvict as a write, but instead discard it. With this patch it will be neither a read, nor write, and as it does not need a response the slave will simply sink it. --- diff --git a/src/mem/cache/base.hh b/src/mem/cache/base.hh index 3baec36d9..a992583fe 100644 --- a/src/mem/cache/base.hh +++ b/src/mem/cache/base.hh @@ -508,9 +508,12 @@ class BaseCache : public MemObject MSHR *allocateWriteBuffer(PacketPtr pkt, Tick time) { - // should only see clean evictions in a read-only cache - assert(!isReadOnly || pkt->cmd == MemCmd::CleanEvict); - assert(pkt->isWrite() && !pkt->isRead()); + // should only see writes or clean evicts here + assert(pkt->isWrite() || pkt->cmd == MemCmd::CleanEvict); + + // if this is a read-only cache we should never see any writes + assert(!(isReadOnly && pkt->isWrite())); + return allocateBufferInternal(&writeBuffer, blockAlign(pkt->getAddr()), blkSize, pkt, time, true); diff --git a/src/mem/packet.cc b/src/mem/packet.cc index b1e6dcd63..80b079138 100644 --- a/src/mem/packet.cc +++ b/src/mem/packet.cc @@ -88,7 +88,7 @@ MemCmd::commandInfo[] = { SET4(IsWrite, NeedsExclusive, IsRequest, HasData), InvalidCmd, "Writeback" }, /* CleanEvict */ - { SET2(IsWrite, IsRequest), InvalidCmd, "CleanEvict" }, + { SET1(IsRequest), InvalidCmd, "CleanEvict" }, /* SoftPFReq */ { SET4(IsRead, IsRequest, IsSWPrefetch, NeedsResponse), SoftPFResp, "SoftPFReq" },