From e7acca2ba3c44d5d2ab3154fb04ce8a0b9d14801 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Tue, 1 Sep 2009 22:50:46 +0000
Subject: [PATCH] * Cleanup the kernel coverage analysis.

svn path=/nixos/trunk/; revision=16919
---
 lib/test-driver/test-driver.pl           | 21 +++++++++++++++++++++
 modules/testing/test-instrumentation.nix |  5 +++++
 tests/subversion.nix                     |  8 --------
 3 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/lib/test-driver/test-driver.pl b/lib/test-driver/test-driver.pl
index f76d01199a5d..739753baeb1c 100644
--- a/lib/test-driver/test-driver.pl
+++ b/lib/test-driver/test-driver.pl
@@ -22,6 +22,27 @@ sub startAll {
 sub runTests {
     eval "$context $ENV{tests}";
     die $@ if $@;
+
+    # Copy the kernel coverage data for each machine, if the kernel
+    # has been compiled with coverage instrumentation.
+    foreach my $vm (values %vms) {
+        my ($status, $out) = $vm->execute("test -e /proc/gcov");
+        next if $status != 0;
+
+        # Figure out where to put the *.gcda files so that the report
+        # generator can find the corresponding kernel sources.
+        my $kernelDir = $vm->mustSucceed("echo \$(dirname \$(readlink -f /var/run/current-system/kernel))/.build/linux-*");
+        chomp $kernelDir;
+        my $coverageDir = "/hostfs" . $vm->stateDir() . "/coverage-data/$kernelDir";
+
+        # Copy all the *.gcda files.  The ones under
+        # /proc/gcov/module/nix/store are the kernel modules in the
+        # initrd to which we have applied nuke-refs in
+        # makeModuleClosure.  This confuses the gcov module a bit.
+        $vm->execute("for i in \$(cd /proc/gcov && find -name module -prune -o -name '*.gcda'); do echo \$i; mkdir -p $coverageDir/\$(dirname \$i); cp -v /proc/gcov/\$i $coverageDir/\$i; done");
+
+        $vm->execute("for i in \$(cd /proc/gcov/module/nix/store/*/.build/* && find -name module -prune -o -name '*.gcda'); do mkdir -p $coverageDir/\$(dirname \$i); cp /proc/gcov/module/nix/store/*/.build/*/\$i $coverageDir/\$i; done");
+    }
 }
 
 
diff --git a/modules/testing/test-instrumentation.nix b/modules/testing/test-instrumentation.nix
index b64dc70ab307..85f892e887f4 100644
--- a/modules/testing/test-instrumentation.nix
+++ b/modules/testing/test-instrumentation.nix
@@ -31,6 +31,11 @@ with pkgs.lib;
           ln -s /hostfs/$hostTmpDir/coverage-data /tmp/coverage-data
         )
       '';
+
+    # If the kernel has been built with coverage instrumentation, make
+    # it available under /proc/gcov.
+    boot.kernelModules = [ "gcov-proc" ];
+      
   };
 
 }
diff --git a/tests/subversion.nix b/tests/subversion.nix
index 481ab12a4abe..5c26c9cd8026 100644
--- a/tests/subversion.nix
+++ b/tests/subversion.nix
@@ -51,7 +51,6 @@ rec {
         { config, pkgs, ... }:
 
         {
-          boot.kernelModules = [ "gcov-proc" ];
           services.httpd.enable = true;
           services.httpd.adminAddr = "e.dolstra@tudelft.nl";
           services.httpd.extraSubservices =
@@ -131,13 +130,6 @@ rec {
       # Stop Apache to gather all the coverage data.
       $webserver->stopJob("httpd");
       $webserver->execute("sleep 10"); # !!!
-
-      # !!! move this to build-vms.nix
-      my $kernelDir = $webserver->mustSucceed("echo \$(dirname \$(readlink -f /var/run/current-system/kernel))/.build/linux-*");
-      chomp $kernelDir;
-      my $coverageDir = "/hostfs" . $webserver->stateDir() . "/coverage-data/$kernelDir";
-      $webserver->execute("for i in \$(cd /proc/gcov && find -name module -prune -o -name '*.gcda'); do echo \$i; mkdir -p $coverageDir/\$(dirname \$i); cp -v /proc/gcov/\$i $coverageDir/\$i; done");
-      $webserver->execute("for i in \$(cd /proc/gcov/module/nix/store/*/.build/* && find -name module -prune -o -name '*.gcda'); do mkdir -p $coverageDir/\$(dirname \$i); cp /proc/gcov/module/nix/store/*/.build/*/\$i $coverageDir/\$i; done");
     '';
 
   report = makeReport test;