From 12d57945479b016f46c3e3355e592239c932164a Mon Sep 17 00:00:00 2001
From: Ciro Santilli <ciro.santilli@gmail.com>
Date: Thu, 30 Aug 2018 09:54:28 +0100
Subject: [PATCH] run: -l latest checkpoint restore

Run is in theory done now, but all edge functionality needs double testing.
---
 README.adoc |  4 ++--
 common.py   | 17 ++++++++++++++++-
 run         | 21 +++++++++------------
 3 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/README.adoc b/README.adoc
index ba92270..201903d 100644
--- a/README.adoc
+++ b/README.adoc
@@ -8535,7 +8535,7 @@ The out of build tree is required, because otherwise Buildroot would copy the ou
 
 By default, we use `configs/example/fs.py` script.
 
-The `-X-b` option enables the alternative `configs/example/arm/fs_bigLITTLE.py` script instead.
+The `--gem5-biglittle` option enables the alternative `configs/example/arm/fs_bigLITTLE.py` script instead.
 
 First apply:
 
@@ -8546,7 +8546,7 @@ patch -d gem5/gem5 -p1 < patches/manual/gem5-biglittle.patch
 then:
 
 ....
-./run -a A -g -X-b
+./run -a A -g --gem5-biglittle
 ....
 
 Advantages over `fs.py`:
diff --git a/common.py b/common.py
index 606a802..7a46f0d 100644
--- a/common.py
+++ b/common.py
@@ -3,6 +3,7 @@
 import argparse
 import base64
 import imp
+import re
 import subprocess
 import os
 import shlex
@@ -33,6 +34,20 @@ this = sys.modules[__name__]
 def base64_encode(string):
     return base64.b64encode(string.encode()).decode()
 
+def error(msg):
+    print('error: {}'.format(msg), file=sys.stderr)
+    sys.exit(1)
+
+def gem_list_checkpoint_dirs():
+    """
+    List checkpoint directory, oldest first.
+    """
+    global this
+    prefix_re = re.compile(this.gem5_cpt_prefix)
+    files = list(filter(lambda x: os.path.isdir(os.path.join(this.m5out_dir, x)) and prefix_re.search(x), os.listdir(this.m5out_dir)))
+    files.sort(key=lambda x: os.path.getmtime(os.path.join(this.m5out_dir, x)))
+    return files
+
 def get_argparse(default_args=None, argparse_args=None):
     """
     Return an argument parser with common arguments set.
@@ -245,7 +260,7 @@ arch_map = {
     'A': 'aarch64',
     'x': 'x86_64',
 }
-gem5_cpt_pref = '^cpt\.'
+gem5_cpt_prefix = '^cpt\.'
 sha = subprocess.check_output(['git', '-C', root_dir, 'log', '-1', '--format=%H']).decode().rstrip()
 
 # Config file. TODO move to decent python setup.
diff --git a/run b/run
index a76e540..5f03625 100755
--- a/run
+++ b/run
@@ -224,11 +224,9 @@ if args.gem5:
         ]
     )
     if args.gem5_biglittle:
-        # TODO port
-        # if args.gem5_restore_last_checkpoint is not None:
-        #     cmd += [
-        #         '--restore-from='${common.m5out_dir}/$(ls -crt "common.m5out_dir" | grep -E "common.gem5_cpt_pref" | tail -n "$gem5_restore_last_checkpoint" | head -n 1
-        #     ]
+        if args.gem5_restore_last_checkpoint is not None:
+            cpt_dir = common.gem_list_checkpoint_dirs()[-args.gem5_restore_last_checkpoint]
+            extra_emulator_args.extend(['--restore-from', os.path.join(common.m5out_dir, cpt_dir)])
         cmd += [
             os.path.join(common.gem5_src_dir, 'configs', 'example', 'arm', 'fs_bigLITTLE.py'),
             '--big-cpus', '2',
@@ -240,10 +238,10 @@ if args.gem5:
         ]
     else:
         # TODO port
-        #if [ -n "$gem5_restore_last_checkpoint" ]; then
-        #    latest_cpt_basename="$(ls -crt "common.m5out_dir" | grep -E "common.gem5_cpt_pref" | tail -n "$gem5_restore_last_checkpoint" | head -n 1)"
-        #    n="$(ls -1 "common.m5out_dir" | grep -E "common.gem5_cpt_pref" | sort -k 2 -n -t . | grep -n "$latest_cpt_basename" | cut -d : -f 1)"
-        #    cmd += -r ${n} \\
+        if args.gem5_restore_last_checkpoint is not None:
+            cpt_dirs = common.gem_list_checkpoint_dirs()
+            cpt_dir = cpt_dirs[-args.gem5_restore_last_checkpoint]
+            extra_emulator_args.extend(['-r', str(sorted(cpt_dirs).index(cpt_dir) + 1)])
         cmd += [
             os.path.join(common.gem5_src_dir, 'configs', 'example', 'fs.py'),
             '--disk-image', common.ext2_file,
@@ -401,7 +399,7 @@ with subprocess.Popen(cmd, stdout=stdout, stderr=stderr, env=env) as proc:
                     break
 signal.signal(signal.SIGINT, signal.SIG_DFL)
 if proc.returncode != 0:
-    sys.exit(proc.returncode)
+    common.error('simulator exited with status != 0')
 # Check if guest panicked.
 if args.gem5:
     # We have to do some parsing here because gem5 exits with status 0 even when panic happens.
@@ -413,5 +411,4 @@ panic_re = re.compile(panic_msg)
 with open(common.termout_file, 'r') as logfile:
     for line in logfile:
         if panic_re.search(line):
-            print('Simulation error detected by parsing logs. Exiting with status 1.', file=sys.stderr)
-            sys.exit(1)
+            common.error('simulation error detected by parsing logs')