From fbe3e22474184e537fe74f4e86277056026f0514 Mon Sep 17 00:00:00 2001 From: Kevin Lim Date: Thu, 6 Jul 2006 17:57:20 -0400 Subject: Fix the O3CPU to support the multi-pass method for checking if the system has fully drained. src/cpu/o3/commit.hh: src/cpu/o3/commit_impl.hh: src/cpu/o3/decode.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/iew.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/rename.hh: src/cpu/o3/rename_impl.hh: Return a value so that the CPU can instantly return from draining if the pipeline is already drained. src/cpu/o3/cpu.cc: Use values returned from pipeline stages so that the CPU can instantly return from draining if the pipeline is already drained. --HG-- extra : convert_revision : d8ef6b811644ea67c8b40c4719273fa224105811 --- src/cpu/o3/commit.hh | 2 +- src/cpu/o3/commit_impl.hh | 10 +++++++++- src/cpu/o3/cpu.cc | 25 +++++++++++++++++++------ src/cpu/o3/decode.hh | 2 +- src/cpu/o3/decode_impl.hh | 3 ++- src/cpu/o3/fetch.hh | 2 +- src/cpu/o3/fetch_impl.hh | 3 ++- src/cpu/o3/iew.hh | 2 +- src/cpu/o3/iew_impl.hh | 3 ++- src/cpu/o3/rename.hh | 2 +- src/cpu/o3/rename_impl.hh | 3 ++- 11 files changed, 41 insertions(+), 16 deletions(-) (limited to 'src/cpu') diff --git a/src/cpu/o3/commit.hh b/src/cpu/o3/commit.hh index 49ff5cdad..c39bc10f9 100644 --- a/src/cpu/o3/commit.hh +++ b/src/cpu/o3/commit.hh @@ -188,7 +188,7 @@ class DefaultCommit void initStage(); /** Initializes the draining of commit. */ - void drain(); + bool drain(); /** Resumes execution after draining. */ void resume(); diff --git a/src/cpu/o3/commit_impl.hh b/src/cpu/o3/commit_impl.hh index 2eb05afac..b50c9a898 100644 --- a/src/cpu/o3/commit_impl.hh +++ b/src/cpu/o3/commit_impl.hh @@ -350,10 +350,18 @@ DefaultCommit::initStage() } template -void +bool DefaultCommit::drain() { drainPending = true; + + // If it's already drained, return true. + if (rob->isEmpty() && !iewStage->hasStoresToWB()) { + cpu->signalDrained(); + return true; + } + + return false; } template diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc index b182d5ca7..3a52fe4c2 100644 --- a/src/cpu/o3/cpu.cc +++ b/src/cpu/o3/cpu.cc @@ -712,19 +712,27 @@ bool FullO3CPU::drain(Event *drain_event) { drainCount = 0; - drainEvent = drain_event; fetch.drain(); decode.drain(); rename.drain(); iew.drain(); commit.drain(); + // A bit of a hack...set the drainEvent after all the drain() + // calls have been made, that way if all of the stages drain + // immediately, the signalDrained() function knows not to call + // process on the drain event. + drainEvent = drain_event; // Wake the CPU and record activity so everything can drain out if - // the CPU is currently idle. - wakeCPU(); - activityRec.activity(); + // the CPU was not able to immediately drain. + if (_status != Drained) { + wakeCPU(); + activityRec.activity(); - return false; + return false; + } else { + return true; + } } template @@ -751,8 +759,13 @@ FullO3CPU::signalDrained() if (++drainCount == NumStages) { if (tickEvent.scheduled()) tickEvent.squash(); + _status = Drained; - drainEvent->process(); + + if (drainEvent) { + drainEvent->process(); + drainEvent = NULL; + } } assert(drainCount <= 5); } diff --git a/src/cpu/o3/decode.hh b/src/cpu/o3/decode.hh index 1e96f1884..7f5ecbc26 100644 --- a/src/cpu/o3/decode.hh +++ b/src/cpu/o3/decode.hh @@ -110,7 +110,7 @@ class DefaultDecode void setActiveThreads(std::list *at_ptr); /** Drains the decode stage. */ - void drain(); + bool drain(); /** Resumes execution after a drain. */ void resume() { } diff --git a/src/cpu/o3/decode_impl.hh b/src/cpu/o3/decode_impl.hh index 71637883b..8b851c032 100644 --- a/src/cpu/o3/decode_impl.hh +++ b/src/cpu/o3/decode_impl.hh @@ -165,11 +165,12 @@ DefaultDecode::setActiveThreads(list *at_ptr) } template -void +bool DefaultDecode::drain() { // Decode is done draining at any time. cpu->signalDrained(); + return true; } template diff --git a/src/cpu/o3/fetch.hh b/src/cpu/o3/fetch.hh index 9611f0455..a793c7361 100644 --- a/src/cpu/o3/fetch.hh +++ b/src/cpu/o3/fetch.hh @@ -181,7 +181,7 @@ class DefaultFetch void processCacheCompletion(PacketPtr pkt); /** Begins the drain of the fetch stage. */ - void drain(); + bool drain(); /** Resumes execution after a drain. */ void resume(); diff --git a/src/cpu/o3/fetch_impl.hh b/src/cpu/o3/fetch_impl.hh index 500b5304e..c0cc189f2 100644 --- a/src/cpu/o3/fetch_impl.hh +++ b/src/cpu/o3/fetch_impl.hh @@ -385,12 +385,13 @@ DefaultFetch::processCacheCompletion(PacketPtr pkt) } template -void +bool DefaultFetch::drain() { // Fetch is ready to drain at any time. cpu->signalDrained(); drainPending = true; + return true; } template diff --git a/src/cpu/o3/iew.hh b/src/cpu/o3/iew.hh index 774b6dcbd..4908a6649 100644 --- a/src/cpu/o3/iew.hh +++ b/src/cpu/o3/iew.hh @@ -144,7 +144,7 @@ class DefaultIEW void setScoreboard(Scoreboard *sb_ptr); /** Drains IEW stage. */ - void drain(); + bool drain(); /** Resumes execution after a drain. */ void resume(); diff --git a/src/cpu/o3/iew_impl.hh b/src/cpu/o3/iew_impl.hh index c3aa748ae..0d82645e3 100644 --- a/src/cpu/o3/iew_impl.hh +++ b/src/cpu/o3/iew_impl.hh @@ -354,11 +354,12 @@ DefaultIEW::setScoreboard(Scoreboard *sb_ptr) } template -void +bool DefaultIEW::drain() { // IEW is ready to drain at any time. cpu->signalDrained(); + return true; } template diff --git a/src/cpu/o3/rename.hh b/src/cpu/o3/rename.hh index 538dd9bb4..034087feb 100644 --- a/src/cpu/o3/rename.hh +++ b/src/cpu/o3/rename.hh @@ -158,7 +158,7 @@ class DefaultRename void setScoreboard(Scoreboard *_scoreboard); /** Drains the rename stage. */ - void drain(); + bool drain(); /** Resumes execution after a drain. */ void resume() { } diff --git a/src/cpu/o3/rename_impl.hh b/src/cpu/o3/rename_impl.hh index fddbae3db..805a72808 100644 --- a/src/cpu/o3/rename_impl.hh +++ b/src/cpu/o3/rename_impl.hh @@ -257,11 +257,12 @@ DefaultRename::setScoreboard(Scoreboard *_scoreboard) } template -void +bool DefaultRename::drain() { // Rename is ready to switch out at any time. cpu->signalDrained(); + return true; } template -- cgit v1.2.3