base: Add support for changing output directories

This changeset adds support for changing the simulator output
directory. This can be useful when the simulation goes through several
stages (e.g., a warming phase, a simulation phase, and a verification
phase) since it allows the output from each stage to be located in a
different directory. Relocation is done by calling core.setOutputDir()
from Python or simout.setOutputDirectory() from C++.

This change affects several parts of the design of the gem5's output
subsystem. First, files returned by an OutputDirectory instance (e.g.,
simout) are of the type OutputStream instead of a std::ostream. This
allows us to do some more book keeping and control re-opening of files
when the output directory is changed. Second, new subdirectories are
OutputDirectory instances, which should be used to create files in
that sub-directory.

Signed-off-by: Andreas Sandberg <andreas@sandberg.pp.se>
[sascha.bischoff@arm.com: Rebased patches onto a newer gem5 version]
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

5 files changed, 13 insertions, 12 deletions

diff --git a/src/cpu/base.cc b/src/cpu/base.cc
index 0e8c2930f..22fca4dc5 100644
--- a/src/cpu/base.cc
+++ b/src/cpu/base.cc
@@ -218,9 +218,7 @@ BaseCPU::BaseCPU(Params *p, bool is_checker)
     functionTracingEnabled = false;
     if (p->function_trace) {
         const string fname = csprintf("ftrace.%s", name());
-        functionTraceStream = simout.find(fname);
-        if (!functionTraceStream)
-            functionTraceStream = simout.create(fname);
+        functionTraceStream = simout.findOrCreate(fname)->stream();
 
         currentFunctionStart = currentFunctionEnd = 0;
         functionEntryTick = p->function_trace_start;
diff --git a/src/cpu/o3/thread_state.hh b/src/cpu/o3/thread_state.hh
index 19235c44c..7765f86ea 100644
--- a/src/cpu/o3/thread_state.hh
+++ b/src/cpu/o3/thread_state.hh
@@ -144,8 +144,10 @@ struct O3ThreadState : public ThreadState {
 
     void dumpFuncProfile()
     {
-        std::ostream *os = simout.create(csprintf("profile.%s.dat", cpu->name()));
-        profile->dump(tc, *os);
+        OutputStream *os(
+            simout.create(csprintf("profile.%s.dat", cpu->name())));
+        profile->dump(tc, *os->stream());
+        simout.close(os);
     }
 };
 
diff --git a/src/cpu/simple/probes/simpoint.cc b/src/cpu/simple/probes/simpoint.cc
index 2de3cd420..4f4b5da39 100644
--- a/src/cpu/simple/probes/simpoint.cc
+++ b/src/cpu/simple/probes/simpoint.cc
@@ -126,13 +126,13 @@ SimPoint::profile(const std::pair<SimpleThread*, StaticInstPtr>& p)
             std::sort(counts.begin(), counts.end());
 
             // Print output BBV info
-            *simpointStream << "T";
+            *simpointStream->stream() << "T";
             for (auto cnt_itr = counts.begin(); cnt_itr != counts.end();
                     ++cnt_itr) {
-                *simpointStream << ":" << cnt_itr->first
+                *simpointStream->stream() << ":" << cnt_itr->first
                                 << ":" << cnt_itr->second << " ";
             }
-            *simpointStream << "\n";
+            *simpointStream->stream() << "\n";
 
             intervalDrift = (intervalCount + intervalDrift) - intervalSize;
             intervalCount = 0;
diff --git a/src/cpu/simple/probes/simpoint.hh b/src/cpu/simple/probes/simpoint.hh
index 2f4ed080d..2873ae410 100644
--- a/src/cpu/simple/probes/simpoint.hh
+++ b/src/cpu/simple/probes/simpoint.hh
@@ -43,6 +43,7 @@
 
 #include <unordered_map>
 
+#include "base/output.hh"
 #include "cpu/simple_thread.hh"
 #include "params/SimPoint.hh"
 #include "sim/probe/probe.hh"
@@ -97,7 +98,7 @@ class SimPoint : public ProbeListenerObject
     /** Excess inst count from previous interval*/
     uint64_t intervalDrift;
     /** Pointer to SimPoint BBV output stream */
-    std::ostream *simpointStream;
+    OutputStream *simpointStream;
 
     /** Basic Block information */
     struct BBInfo {
diff --git a/src/cpu/simple_thread.cc b/src/cpu/simple_thread.cc
index 5e457f692..33c5b47ea 100644
--- a/src/cpu/simple_thread.cc
+++ b/src/cpu/simple_thread.cc
@@ -154,9 +154,9 @@ SimpleThread::startup()
 void
 SimpleThread::dumpFuncProfile()
 {
-    std::ostream *os = simout.create(csprintf("profile.%s.dat",
-                                              baseCpu->name()));
-    profile->dump(tc, *os);
+    OutputStream *os(simout.create(csprintf("profile.%s.dat", baseCpu->name())));
+    profile->dump(tc, *os->stream());
+    simout.close(os);
 }
 
 void