From: Gabriel Corona <gabriel.corona@loria.fr>
Date: Thu, 3 Apr 2014 16:18:46 +0000 (+0200)
Subject: [mc] Make snapshots compatible with SMPI privatization of global variables
X-Git-Tag: v3_11~134^2~1
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/f4782c312dc48a0fdce1934a03f8392ae4f9ce5e

[mc] Make snapshots compatible with SMPI privatization of global variables

Not handled yet:
* State comparaison is not handled in this commit;
* Address process/snapshot translation support.

Still to do: make a clean API for the privatization.
---

diff --git a/src/mc/mc_checkpoint.c b/src/mc/mc_checkpoint.c
index e482c42aa4..92d7616849 100644
--- a/src/mc/mc_checkpoint.c
+++ b/src/mc/mc_checkpoint.c
@@ -12,6 +12,7 @@
 #include "mc_private.h"
 #include "xbt/module.h"
 #include <xbt/mmalloc.h>
+#include "../smpi/private.h"
 
 #include "xbt/mmalloc/mmprivate.h"
 
@@ -65,6 +66,13 @@ void MC_free_snapshot(mc_snapshot_t snapshot){
   xbt_free(snapshot->stack_sizes);
   xbt_dynar_free(&(snapshot->stacks));
   xbt_dynar_free(&(snapshot->to_ignore));
+
+  size_t n = snapshot->nb_processes;
+  for(i=0; i!=n; ++i) {
+    MC_region_destroy(snapshot->privatization_regions[i]);
+  }
+  xbt_free(snapshot->privatization_regions);
+
   xbt_free(snapshot);
 }
 
@@ -102,6 +110,7 @@ static void MC_snapshot_add_region(mc_snapshot_t snapshot, int type, void *start
 } 
 
 static void MC_get_memory_regions(mc_snapshot_t snapshot){
+  size_t i;
 
   void* start_heap = ((xbt_mheap_t)std_heap)->base;
   void* end_heap   = ((xbt_mheap_t)std_heap)->breakval;
@@ -109,7 +118,17 @@ static void MC_get_memory_regions(mc_snapshot_t snapshot){
   snapshot->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
 
   MC_snapshot_add_region(snapshot, 1,  mc_libsimgrid_info->start_rw, mc_libsimgrid_info->end_rw - mc_libsimgrid_info->start_rw);
-  MC_snapshot_add_region(snapshot, 2,  mc_binary_info->start_rw, mc_binary_info->end_rw - mc_binary_info->start_rw);
+  if(!smpi_privatize_global_variables) {
+    MC_snapshot_add_region(snapshot, 2,  mc_binary_info->start_rw, mc_binary_info->end_rw - mc_binary_info->start_rw);
+    snapshot->privatization_regions = NULL;
+    snapshot->privatization_index = -1;
+  } else {
+    snapshot->privatization_regions = xbt_new(mc_mem_region_t, SIMIX_process_count());
+    for (i=0; i< SIMIX_process_count(); i++){
+      snapshot->privatization_regions[i] = MC_region_new(-1, mappings[i], size_data_exe);
+    }
+    snapshot->privatization_index = loaded_page;
+  }
 }
 
 /** @brief Finds the range of the different memory segments and binary paths */
@@ -479,9 +498,19 @@ mc_snapshot_t MC_take_snapshot(int num_state){
 void MC_restore_snapshot(mc_snapshot_t snapshot){
   unsigned int i;
   for(i=0; i < NB_REGIONS; i++){
-    MC_region_restore(snapshot->regions[i]);
+    // For privatized, variables we decided it was not necessary to take the snapshot:
+    if(snapshot->regions[i])
+      MC_region_restore(snapshot->regions[i]);
   }
 
+  if(snapshot->privatization_regions) {
+    for (i=0; i< SIMIX_process_count(); i++){
+      if(snapshot->privatization_regions[i]) {
+        MC_region_restore(snapshot->privatization_regions[i]);
+      }
+    }
+    switch_data_segment(snapshot->privatization_index);
+  }
 }
 
 void* mc_translate_address(uintptr_t addr, mc_snapshot_t snapshot) {
diff --git a/src/mc/mc_private.h b/src/mc/mc_private.h
index 20e4ab832f..0de75609ec 100644
--- a/src/mc/mc_private.h
+++ b/src/mc/mc_private.h
@@ -48,6 +48,8 @@ typedef struct s_mc_snapshot{
   size_t heap_bytes_used;
   mc_mem_region_t regions[NB_REGIONS];
   int nb_processes;
+  mc_mem_region_t* privatization_regions;
+  int privatization_index;
   size_t *stack_sizes;
   xbt_dynar_t stacks;
   xbt_dynar_t to_ignore;
diff --git a/src/smpi/private.h b/src/smpi/private.h
index e692c3898e..74ee1b6a32 100644
--- a/src/smpi/private.h
+++ b/src/smpi/private.h
@@ -589,5 +589,8 @@ void TRACE_smpi_finalize(int rank);
 
 const char* encode_datatype(MPI_Datatype datatype);
 
+// TODO, make this static and expose it more cleanly
+extern void** mappings;
+extern int loaded_page;
 
 #endif