From 48de9544b7eac2f9d40ea34a42c1d1a3d7ccbbfe Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Date: Tue, 24 May 2011 13:25:02 +0200
Subject: [PATCH] Stop locking the mutex on data_receive.

---
 NOTES       |  4 ++++
 process.cpp | 22 +++++++++++-----------
 process.h   |  1 +
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/NOTES b/NOTES
index 5399a4c..53bce11 100644
--- a/NOTES
+++ b/NOTES
@@ -71,3 +71,7 @@ process::expected_load          Current load estimation.
                                   minus pending sends.
                                 * With bookkeeping, it corresponds to the
                                   "virtual load".
+
+process::received_load          Real load received from neighbors.
+                                Used when receiveing data messages, and then
+                                added to real_load.
diff --git a/process.cpp b/process.cpp
index 8a73f38..2de3016 100644
--- a/process.cpp
+++ b/process.cpp
@@ -50,6 +50,7 @@ process::process(int argc, char* argv[])
     expected_load = real_load;
     total_load_running += real_load;
     total_load_init += real_load;
+    received_load = 0.0;
 
     ctrl_close_pending = data_close_pending = neigh.size();
     close_received = false;
@@ -80,6 +81,8 @@ process::~process()
 {
     delete lb_thread;
     total_load_exit += real_load;
+    xbt_assert(received_load == 0.0,
+               "received_load is %g, but should be 0.0 !", received_load);
     if (opt::log_rate < 0)
         return;
     XBT_INFO("Final load after %d:%d iterations: %g",
@@ -169,17 +172,14 @@ void process::compute_loop()
 
     double next_iter_after_date = MSG_get_clock() + opt::min_comp_iter_duration;
     while (still_running()) {
-        // receive
-        mutex.acquire();
-        if (real_load > 0.0)
-            data_receive(0.0);
-        else
-            data_receive(opt::min_comp_iter_duration);
-        mutex.release();
+        // receive (do not block if there is something to compute)
+        data_receive(real_load > 0.0 ? 0.0 : opt::min_comp_iter_duration);
 
         // send
         comm.data_flush(false);
         mutex.acquire();
+        real_load += received_load;
+        received_load = 0.0;
         std::for_each(neigh.begin(), neigh.end(),
                       std::bind(&process::data_send, this, _1));
         mutex.release();
@@ -202,7 +202,6 @@ void process::compute_loop()
 
     XBT_VERB("Going to finalize for %s...", __func__);
     finalizing = true;
-    total_load_running -= real_load;
     XBT_DEBUG("send DATA_CLOSE to %zu neighbor%s",
               neigh.size(), ESSE(neigh.size()));
     std::for_each(neigh.begin(), neigh.end(),
@@ -212,6 +211,9 @@ void process::compute_loop()
         XBT_DEBUG("waiting for %d DATA_CLOSE", data_close_pending);
         data_receive(-1.0);
     }
+    real_load += received_load;
+    received_load = 0.0;
+    total_load_running -= real_load;
     comm.data_flush(true);
 }
 
@@ -382,9 +384,7 @@ void process::handle_message(message* msg, m_host_t from)
     }
     case message::DATA: {
         double ld = msg->get_amount();
-        real_load += ld;
-        if (finalizing)
-            total_load_running -= ld;
+        received_load += ld;
         break;
     }
     case message::CTRL_CLOSE:
diff --git a/process.h b/process.h
index 4686af4..57ece07 100644
--- a/process.h
+++ b/process.h
@@ -102,6 +102,7 @@ private:
                                 // a same information messages
     double real_load;           // current load
     double expected_load;       // expected load in bookkeeping mode
+    double received_load;       // load received from neighbors
 
     mutex_t mutex;              // synchronization between threads
     condition_t cond;
-- 
2.39.5