mesos git commit: Added flag to disable systemd support.

[jo...@apache.org]

Repository: mesos
Updated Branches:
  refs/heads/master e7e6ed610 -> 0c53a34e3


Added flag to disable systemd support.

Review: https://reviews.apache.org/r/43582


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/0c53a34e
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/0c53a34e
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/0c53a34e

Branch: refs/heads/master
Commit: 0c53a34e35c2bd345251281c21a5932448c34683
Parents: e7e6ed6
Author: Joris Van Remoortere <jo...@gmail.com>
Authored: Mon Feb 15 12:30:27 2016 -0500
Committer: Joris Van Remoortere <jo...@gmail.com>
Committed: Mon Feb 15 13:47:48 2016 -0500

----------------------------------------------------------------------
 docs/configuration.md | 12 ++++++++++++
 src/linux/systemd.cpp | 15 ++++++++++++++-
 src/linux/systemd.hpp |  1 +
 src/slave/flags.cpp   |  8 ++++++++
 src/slave/flags.hpp   |  1 +
 src/slave/main.cpp    |  3 ++-
 6 files changed, 38 insertions(+), 2 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/docs/configuration.md
----------------------------------------------------------------------
diff --git a/docs/configuration.md b/docs/configuration.md
index eea985c..3d82368 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -1508,6 +1508,18 @@ therefore the flag currently does not exist on that platform. (default: true)
 </tr>
 <tr>
   <td>
+    --[no-]systemd_enable_support
+  </td>
+  <td>
+Top level control of systemd support. When enabled, features such as
+executor life-time extension are enabled unless there is an explicit
+flag to disable these (see other flags). This should be enabled when
+the agent is launched as a systemd unit.
+(default: true)
+  </td>
+</tr>
+<tr>
+  <td>
     --systemd_runtime_directory=VALUE
   </td>
   <td>

http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/src/linux/systemd.cpp
----------------------------------------------------------------------
diff --git a/src/linux/systemd.cpp b/src/linux/systemd.cpp
index 13b5c82..e120d2c 100644
--- a/src/linux/systemd.cpp
+++ b/src/linux/systemd.cpp
@@ -39,6 +39,13 @@ int DELEGATE_MINIMUM_VERSION = 218;
 
 Flags::Flags()
 {
+  add(&Flags::enabled,
+      "enabled",
+      "Top level control of systemd support. When enabled, features such as\n"
+      "processes life-time extension are enabled unless there is an explicit\n"
+      "flag to disable these (see other flags).",
+      true);
+
   add(&Flags::runtime_directory,
       "runtime_directory",
       "The path to the systemd system run time directory\n",
@@ -108,6 +115,12 @@ Try<Nothing> initialize(const Flags& flags)
 
   systemd_flags = new Flags(flags);
 
+  // Do not initialize any state if we do not have systemd support enabled.
+  if (!systemd_flags->enabled) {
+    initialized->done();
+    return Nothing();
+  }
+
   // If flags->runtime_directory doesn't exist, then we can't proceed.
   if (!os::exists(CHECK_NOTNULL(systemd_flags)->runtime_directory)) {
     return Error("Failed to locate systemd runtime directory: " +
@@ -245,7 +258,7 @@ bool exists()
 
 bool enabled()
 {
-  return exists() && systemd_flags != NULL;
+  return systemd_flags != NULL && flags().enabled && exists();
 }
 
 

http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/src/linux/systemd.hpp
----------------------------------------------------------------------
diff --git a/src/linux/systemd.hpp b/src/linux/systemd.hpp
index d868fda..6b240b9 100644
--- a/src/linux/systemd.hpp
+++ b/src/linux/systemd.hpp
@@ -59,6 +59,7 @@ class Flags : public virtual flags::FlagsBase
 public:
   Flags();
 
+  bool enabled;
   std::string runtime_directory;
   std::string cgroups_hierarchy;
 };

http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/src/slave/flags.cpp
----------------------------------------------------------------------
diff --git a/src/slave/flags.cpp b/src/slave/flags.cpp
index 14ad4dc..46ccf7f 100644
--- a/src/slave/flags.cpp
+++ b/src/slave/flags.cpp
@@ -389,6 +389,14 @@ mesos::internal::slave::Flags::Flags()
       "supported by the cgroups/cpu isolator.",
       true);
 
+  add(&Flags::systemd_enable_support,
+      "systemd_enable_support",
+      "Top level control of systemd support. When enabled, features such as\n"
+      "executor life-time extension are enabled unless there is an explicit\n"
+      "flag to disable these (see other flags). This should be enabled when\n"
+      "the agent is launched as a systemd unit.",
+      true);
+
   add(&Flags::systemd_runtime_directory,
       "systemd_runtime_directory",
       "The path to the systemd system run time directory\n",

http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/src/slave/flags.hpp
----------------------------------------------------------------------
diff --git a/src/slave/flags.hpp b/src/slave/flags.hpp
index 20232d6..3704376 100644
--- a/src/slave/flags.hpp
+++ b/src/slave/flags.hpp
@@ -93,6 +93,7 @@ public:
   Duration perf_interval;
   Duration perf_duration;
   bool revocable_cpu_low_priority;
+  bool systemd_enable_support;
   std::string systemd_runtime_directory;
 #endif
   Option<Firewall> firewall_rules;

http://git-wip-us.apache.org/repos/asf/mesos/blob/0c53a34e/src/slave/main.cpp
----------------------------------------------------------------------
diff --git a/src/slave/main.cpp b/src/slave/main.cpp
index 222198c..e3a4d13 100644
--- a/src/slave/main.cpp
+++ b/src/slave/main.cpp
@@ -236,10 +236,11 @@ int main(int argc, char** argv)
 
 #ifdef __linux__
   // Initialize systemd if it exists.
-  if (systemd::exists()) {
+  if (systemd::exists() && flags.systemd_enable_support) {
     LOG(INFO) << "Inializing systemd state";
 
     systemd::Flags systemdFlags;
+    systemdFlags.enabled = flags.systemd_enable_support;
     systemdFlags.runtime_directory = flags.systemd_runtime_directory;
     systemdFlags.cgroups_hierarchy = flags.cgroups_hierarchy;