[mc] Only enable KSM on snapshots and not on main memory

[simgrid.git] / src / xbt / mmalloc / mmorecore.c

diff --git a/src/xbt/mmalloc/mmorecore.c b/src/xbt/mmalloc/mmorecore.c
index dfd9cf7..9fbf7a9 100644 (file)
--- a/src/xbt/mmalloc/mmorecore.c
+++ b/src/xbt/mmalloc/mmorecore.c
@@ -1,16 +1,14 @@
-/* Support for an sbrk-like function that uses mmap.
-   Copyright 1992, 2000 Free Software Foundation, Inc.
+/* Support for an sbrk-like function that uses mmap. */
 
-   Contributed by Fred Fish at Cygnus Support.   fnf@cygnus.com */
-
-/* Copyright (c) 2010-2012. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2010-2014. The SimGrid Team.
+ * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
 
-#ifndef MAP_ANONYMOUS
-#define MAP_ANONYMOUS MAP_ANON
-#endif
+/* Copyright 1992, 2000 Free Software Foundation, Inc.
+
+   Contributed by Fred Fish at Cygnus Support.   fnf@cygnus.com */
 
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>             /* Prototypes for lseek */
@@ -18,18 +16,16 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <sys/mman.h>
+#include <sys/wait.h>
 
 #include "mmprivate.h"
 
-/* Cache the pagesize for the current host machine.  Note that if the host
-   does not readily provide a getpagesize() function, we need to emulate it
-   elsewhere, not clutter up this file with lots of kluges to try to figure
-   it out. */
-
-static size_t pagesize;
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
 
-#define PAGE_ALIGN(addr) (void*) (((long)(addr) + pagesize - 1) & \
-                                  ~(pagesize - 1))
+#define PAGE_ALIGN(addr) (void*) (((long)(addr) + xbt_pagesize - 1) &   \
+                                  ~((long)xbt_pagesize - 1))
 
 /* Return MAP_PRIVATE if MDP represents /dev/zero.  Otherwise, return
    MAP_SHARED.  */
@@ -53,7 +49,7 @@ static size_t pagesize;
 
     It never returns NULL. Instead, it dies verbosely on errors. */
 
-void *mmorecore(struct mdesc *mdp, int size)
+void *mmorecore(struct mdesc *mdp, ssize_t size)
 {
   ssize_t test = 0;
   void *result; // please keep it uninitialized to track issues
@@ -64,8 +60,6 @@ void *mmorecore(struct mdesc *mdp, int size)
   char buf = 0;                 /* Single byte to write to extend mapped file */
 
 //  fprintf(stderr,"increase %p by %u\n",mdp,size);
-  if (pagesize == 0)
-    pagesize = getpagesize();
 
   if (size == 0) {
     /* Just return the current "break" value. */
@@ -123,7 +117,9 @@ void *mmorecore(struct mdesc *mdp, int size)
         char buff[1024];
         fprintf(stderr,"Internal error: mmap returned MAP_FAILED! error: %s\n",strerror(errno));
         sprintf(buff,"cat /proc/%d/maps",getpid());
-        system(buff);
+        int status = system(buff);
+        if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0))
+          fprintf(stderr, "Something went wrong when trying to %s\n", buff);
         sleep(1);
         abort();
       }