[gem5-dev] Change in gem5/gem5[develop]: mem: Fix latency handling in MemDelay

2020-06-16 Thread Nikos Nikoleris (Gerrit) via gem5-dev 
Nikos Nikoleris has submitted this change. (  
https://gem5-review.googlesource.com/c/public/gem5/+/30055 )


Change subject: mem: Fix latency handling in MemDelay
..

mem: Fix latency handling in MemDelay

MemDelay wouldn't consume pre-existing delays in the packet and
therefore the latency it adds would overlap with them. This patch
fixes the MemDelay to properly account for them.

Change-Id: I7330fbf1c8161a21523a0b4aab31c72e34bce650
Signed-off-by: Nikos Nikoleris 
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/30055
Reviewed-by: Daniel Carvalho 
Reviewed-by: Andreas Sandberg 
Maintainer: Andreas Sandberg 
Tested-by: kokoro 
---
M src/mem/mem_delay.cc
1 file changed, 14 insertions(+), 3 deletions(-)

Approvals:
  Andreas Sandberg: Looks good to me, approved; Looks good to me, approved
  Daniel Carvalho: Looks good to me, approved
  kokoro: Regressions pass



diff --git a/src/mem/mem_delay.cc b/src/mem/mem_delay.cc
index 83177fd..9adc072 100644
--- a/src/mem/mem_delay.cc
+++ b/src/mem/mem_delay.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 ARM Limited
+ * Copyright (c) 2018, 2020 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -87,7 +87,12 @@
 bool
 MemDelay::MasterPort::recvTimingResp(PacketPtr pkt)
 {
-const Tick when = curTick() + parent.delayResp(pkt);
+// technically the packet only reaches us after the header delay,
+// and typically we also need to deserialise any payload
+const Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+pkt->headerDelay = pkt->payloadDelay = 0;
+
+const Tick when = curTick() + parent.delayResp(pkt) + receive_delay;

 parent.slavePort.schedTimingResp(pkt, when);

@@ -136,7 +141,13 @@
 bool
 MemDelay::SlavePort::recvTimingReq(PacketPtr pkt)
 {
-const Tick when = curTick() + parent.delayReq(pkt);
+// technically the packet only reaches us after the header
+// delay, and typically we also need to deserialise any
+// payload
+Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+pkt->headerDelay = pkt->payloadDelay = 0;
+
+const Tick when = curTick() + parent.delayReq(pkt) + receive_delay;

 parent.masterPort.schedTimingReq(pkt, when);


--
To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/30055
To unsubscribe, or for help writing mail filters, visit  
https://gem5-review.googlesource.com/settings


Gerrit-Project: public/gem5
Gerrit-Branch: develop
Gerrit-Change-Id: I7330fbf1c8161a21523a0b4aab31c72e34bce650
Gerrit-Change-Number: 30055
Gerrit-PatchSet: 3
Gerrit-Owner: Nikos Nikoleris 
Gerrit-Assignee: Andreas Sandberg 
Gerrit-Reviewer: Andreas Sandberg 
Gerrit-Reviewer: Daniel Carvalho 
Gerrit-Reviewer: Nikos Nikoleris 
Gerrit-Reviewer: kokoro 
Gerrit-MessageType: merged
___
gem5-dev mailing list -- gem5-dev@gem5.org
To unsubscribe send an email to gem5-dev-le...@gem5.org
%(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s

[gem5-dev] Change in gem5/gem5[develop]: mem: Fix latency handling in MemDelay

2020-06-08 Thread Nikos Nikoleris (Gerrit) via gem5-dev 
Nikos Nikoleris has uploaded this change for review. (  
https://gem5-review.googlesource.com/c/public/gem5/+/30055 )



Change subject: mem: Fix latency handling in MemDelay
..

mem: Fix latency handling in MemDelay

MemDelay wouldn't consume pre-existing delays in the packet and
therefore the latency it adds would overlap with them. This patch
fixes the MemDelay to properly account for them.

Change-Id: I7330fbf1c8161a21523a0b4aab31c72e34bce650
Signed-off-by: Nikos Nikoleris 
---
M src/mem/mem_delay.cc
1 file changed, 16 insertions(+), 3 deletions(-)



diff --git a/src/mem/mem_delay.cc b/src/mem/mem_delay.cc
index 83177fd..52c1ca8 100644
--- a/src/mem/mem_delay.cc
+++ b/src/mem/mem_delay.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 ARM Limited
+ * Copyright (c) 2018, 2020 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -87,7 +87,13 @@
 bool
 MemDelay::MasterPort::recvTimingResp(PacketPtr pkt)
 {
-const Tick when = curTick() + parent.delayResp(pkt);
+// technically the packet only reaches us after the header delay,
+// and typically we also need to deserialise any payload (unless
+// the two sides of the bridge are synchronous)
+const Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+pkt->headerDelay = pkt->payloadDelay = 0;
+
+const Tick when = curTick() + parent.delayResp(pkt) + receive_delay;

 parent.slavePort.schedTimingResp(pkt, when);

@@ -136,7 +142,14 @@
 bool
 MemDelay::SlavePort::recvTimingReq(PacketPtr pkt)
 {
-const Tick when = curTick() + parent.delayReq(pkt);
+// technically the packet only reaches us after the header
+// delay, and typically we also need to deserialise any
+// payload (unless the two sides of the bridge are
+// synchronous)
+Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+pkt->headerDelay = pkt->payloadDelay = 0;
+
+const Tick when = curTick() + parent.delayReq(pkt) + receive_delay;

 parent.masterPort.schedTimingReq(pkt, when);


--
To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/30055
To unsubscribe, or for help writing mail filters, visit  
https://gem5-review.googlesource.com/settings


Gerrit-Project: public/gem5
Gerrit-Branch: develop
Gerrit-Change-Id: I7330fbf1c8161a21523a0b4aab31c72e34bce650
Gerrit-Change-Number: 30055
Gerrit-PatchSet: 1
Gerrit-Owner: Nikos Nikoleris 
Gerrit-MessageType: newchange
___
gem5-dev mailing list -- gem5-dev@gem5.org
To unsubscribe send an email to gem5-dev-le...@gem5.org
%(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s