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authorKevin Lim <ktlim@umich.edu>2006-07-06 17:57:20 -0400
committerKevin Lim <ktlim@umich.edu>2006-07-06 17:57:20 -0400
commitfbe3e22474184e537fe74f4e86277056026f0514 (patch)
tree413df0c55d60823ad1c82615e9ee976c67f983ad /src
parente7ccc94ea3cdc6130e66899fd905ca11da958727 (diff)
downloadgem5-fbe3e22474184e537fe74f4e86277056026f0514.tar.xz
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
Diffstat (limited to 'src')
-rw-r--r--src/cpu/o3/commit.hh2
-rw-r--r--src/cpu/o3/commit_impl.hh10
-rw-r--r--src/cpu/o3/cpu.cc25
-rw-r--r--src/cpu/o3/decode.hh2
-rw-r--r--src/cpu/o3/decode_impl.hh3
-rw-r--r--src/cpu/o3/fetch.hh2
-rw-r--r--src/cpu/o3/fetch_impl.hh3
-rw-r--r--src/cpu/o3/iew.hh2
-rw-r--r--src/cpu/o3/iew_impl.hh3
-rw-r--r--src/cpu/o3/rename.hh2
-rw-r--r--src/cpu/o3/rename_impl.hh3
11 files changed, 41 insertions, 16 deletions
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<Impl>::initStage()
}
template <class Impl>
-void
+bool
DefaultCommit<Impl>::drain()
{
drainPending = true;
+
+ // If it's already drained, return true.
+ if (rob->isEmpty() && !iewStage->hasStoresToWB()) {
+ cpu->signalDrained();
+ return true;
+ }
+
+ return false;
}
template <class Impl>
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<Impl>::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 <class Impl>
@@ -751,8 +759,13 @@ FullO3CPU<Impl>::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<unsigned> *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<Impl>::setActiveThreads(list<unsigned> *at_ptr)
}
template <class Impl>
-void
+bool
DefaultDecode<Impl>::drain()
{
// Decode is done draining at any time.
cpu->signalDrained();
+ return true;
}
template <class Impl>
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<Impl>::processCacheCompletion(PacketPtr pkt)
}
template <class Impl>
-void
+bool
DefaultFetch<Impl>::drain()
{
// Fetch is ready to drain at any time.
cpu->signalDrained();
drainPending = true;
+ return true;
}
template <class Impl>
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<Impl>::setScoreboard(Scoreboard *sb_ptr)
}
template <class Impl>
-void
+bool
DefaultIEW<Impl>::drain()
{
// IEW is ready to drain at any time.
cpu->signalDrained();
+ return true;
}
template <class Impl>
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<Impl>::setScoreboard(Scoreboard *_scoreboard)
}
template <class Impl>
-void
+bool
DefaultRename<Impl>::drain()
{
// Rename is ready to switch out at any time.
cpu->signalDrained();
+ return true;
}
template <class Impl>