[project @ 2003-09-15 20:39:38 by sof]

[ghc-hetmet.git] / ghc / rts / MBlock.c

diff --git a/ghc/rts/MBlock.c b/ghc/rts/MBlock.c
index ceb8856..d276be0 100644 (file)
--- a/ghc/rts/MBlock.c
+++ b/ghc/rts/MBlock.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: MBlock.c,v 1.43 2003/03/20 15:43:31 simonmar Exp $
+ * $Id: MBlock.c,v 1.47 2003/06/26 20:49:32 panne Exp $
  *
  * (c) The GHC Team 1998-1999
  *
@@ -21,6 +21,9 @@
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -87,7 +90,7 @@ getMBlock(void)
 // the mmap() interface.
 
 static void *
-my_mmap (void *addr, int size)
+my_mmap (void *addr, lnat size)
 {
     void *ret;
 
@@ -126,11 +129,14 @@ my_mmap (void *addr, int size)
 #endif
 
     if (ret == (void *)-1) {
-       if (errno == ENOMEM) {
+       if (errno == ENOMEM || 
+           (errno == EINVAL && sizeof(void*)==4 && size >= 0xc0000000)) {
+           // If we request more than 3Gig, then we get EINVAL
+           // instead of ENOMEM (at least on Linux).
            prog_belch("out of memory (requested %d bytes)", size);
            stg_exit(EXIT_FAILURE);
        } else {
-           barf("getMBlock: mmap failed");
+           barf("getMBlock: mmap: %s", strerror(errno));
        }
     }
 
@@ -141,7 +147,7 @@ my_mmap (void *addr, int size)
 // mblocks.
 
 static void *
-gen_map_mblocks (int size)
+gen_map_mblocks (lnat size)
 {
     int slop;
     void *ret;
@@ -153,16 +159,25 @@ gen_map_mblocks (int size)
     
     // unmap the slop bits around the chunk we allocated
     slop = (W_)ret & MBLOCK_MASK;
-       
+    
     if (munmap(ret, MBLOCK_SIZE - slop) == -1) {
-       barf("gen_map_mblocks: munmap failed");
+      barf("gen_map_mblocks: munmap failed");
     }
     if (slop > 0 && munmap(ret+size-slop, slop) == -1) {
-       barf("gen_map_mblocks: munmap failed");
+      barf("gen_map_mblocks: munmap failed");
     }
-    
+
     // ToDo: if we happened to get an aligned block, then don't
-    // unmap the excess, just use it.
+    // unmap the excess, just use it. For this to work, you
+    // need to keep in mind the following:
+    //     * Calling my_mmap() with an 'addr' arg pointing to
+    //       already my_mmap()ed space is OK and won't fail.
+    //     * If my_mmap() can't satisfy the request at the
+    //       given 'next_request' address in getMBlocks(), that
+    //       you unmap the extra mblock mmap()ed here (or simply
+    //       satisfy yourself that the slop introduced isn't worth
+    //       salvaging.)
+    // 
 
     // next time, try after the block we just got.
     ret += MBLOCK_SIZE - slop;