Protect concurrent accesses to shared variables in process.

[loba.git] / process.cpp

diff --git a/process.cpp b/process.cpp
index e6c7bc23ffe137c18644d6a163b648cf81e2b07b..36bdff07cfbe8d18bf4eaf1b81d5f0cfa6b8f064 100644 (file)
--- a/process.cpp
+++ b/process.cpp
@@ -16,6 +16,8 @@ XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(proc);
 
 #include "process.h"
 
+mutex_t *process::proc_mutex;
+
 double process::total_load_init = 0.0;
 double process::total_load_running = 0.0;
 double process::total_load_exit = 0.0;
@@ -58,22 +60,21 @@ process::process(int argc, char* argv[])
         rev_neigh.insert(std::make_pair(host, ptr));
     }
 
-    // Note: there should not be race condition with the current
-    // version of Simgrid, when updating the global variables.
-
     prev_load_broadcast = -1;   // force sending of load on first send_all()
     expected_load = real_load;
-    total_load_running += real_load;
-    total_load_init += real_load;
     received_load = 0.0;
 
     idle_duration = 0.0;
     convergence = -1.0;
 
+    proc_mutex->acquire();
     process_counter++;
+    total_load_init += real_load;
+    total_load_running += real_load;
     total_load_average = total_load_running / process_counter;
     load_diff_threshold = (opt::load_ratio_threshold +
                            opt::avg_load_ratio * total_load_average) / 100.0;
+    proc_mutex->release();
 
     ctrl_close_pending = data_close_pending = neigh.size();
     close_received = false;
@@ -103,7 +104,9 @@ process::process(int argc, char* argv[])
 process::~process()
 {
     delete lb_thread;
+    proc_mutex->acquire();
     total_load_exit += real_load;
+    proc_mutex->release();
     xbt_assert(received_load == 0.0,
                "received_load is %g, but should be 0.0 !", received_load);
     if (opt::log_rate < 0)
@@ -121,6 +124,21 @@ process::~process()
     print_loads(true, xbt_log_priority_debug);
 }
 
+double process::get_iter_deviation() const
+{
+    double average_cost = opt::comp_cost(total_load_average); // fixme: get locked?
+    // Do not count idle periods
+    double comp_iter_opt = acc.comp_amount / average_cost;
+/*
+    // Add iterations that could have been achieved while beeing idle
+    // (kept for documentation)
+    double self_speed = MSG_get_host_speed(MSG_host_self());
+    double average_duration = average_cost / self_speed;
+    comp_iter_opt += idle_duration / average_duration;
+*/
+    return comp_iter - comp_iter_opt;
+}
+
 int process::run()
 {
     if (opt::log_rate >= 0) {
@@ -205,25 +223,23 @@ void process::compute_loop()
     double next_iter_after_date = MSG_get_clock() + opt::min_comp_iter_duration;
     double idle_since_date = 0.0;
     while (still_running()) {
+        // receive
+        // if there is something to compute, do not block
+        // else, block the duration of an *lb* iteration
+        data_receive(real_load > 0.0 ? 0.0 : opt::min_lb_iter_duration);
 
-        do {
-            // receive
-            // if there is something to compute, do not block
-            // else, block the duration of an *lb* iteration
-            data_receive(real_load > 0.0 ? 0.0 : opt::min_lb_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();
-
-            ++all_comp_iter;
+        // 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();
 
-        } while (real_load == 0.0);
+        ++all_comp_iter;
+        if (real_load == 0.0)
+            continue;
 
         convergence_check();
 
@@ -257,26 +273,29 @@ void process::compute_loop()
     }
     real_load += received_load;
     received_load = 0.0;
+    proc_mutex->acquire();
     total_load_running -= real_load;
+    proc_mutex->release();
     convergence_check();
     comm.data_flush(true);
 }
 
 void process::convergence_check()
 {
-    double load_diff = std::fabs(real_load - total_load_average);
+    double average = total_load_average; // fixme: get locked?
+    double load_diff = std::fabs(real_load - average);
     bool converged = load_diff <= load_diff_threshold;
 
     if (convergence >= 0.0) {
         if (!converged) {
             XBT_VERB("current load has diverged: %g (%.4g%%)",
-                     real_load, 100.0 * load_diff / total_load_average);
+                     real_load, 100.0 * load_diff / average);
             convergence = -1.0;
         }
     } else {
         if (converged) {
             XBT_VERB("current load has converged: %g (%.4g%%)",
-                     real_load,  100.0 * load_diff / total_load_average);
+                     real_load,  100.0 * load_diff / average);
             convergence = MSG_get_clock();
         }
     }
@@ -314,7 +333,7 @@ bool process::still_running()
         last_status = false;
 
     } else if (100.0 * total_load_running / total_load_init <=
-               opt::load_ratio_threshold) {
+               opt::load_ratio_threshold) { // fixme: get locked?
         // fixme: this check should be implemented with a distributed
         // algorithm, and not a shared global variable!
         XBT_VERB("No more load to balance in system.");