more code

libguile/gc-malloc.c

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+/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002 Free Software Foundation, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307 USA
+ *
+ * As a special exception, the Free Software Foundation gives permission
+ * for additional uses of the text contained in its release of GUILE.
+ *
+ * The exception is that, if you link the GUILE library with other files
+ * to produce an executable, this does not by itself cause the
+ * resulting executable to be covered by the GNU General Public License.
+ * Your use of that executable is in no way restricted on account of
+ * linking the GUILE library code into it.
+ *
+ * This exception does not however invalidate any other reasons why
+ * the executable file might be covered by the GNU General Public License.
+ *
+ * This exception applies only to the code released by the
+ * Free Software Foundation under the name GUILE.  If you copy
+ * code from other Free Software Foundation releases into a copy of
+ * GUILE, as the General Public License permits, the exception does
+ * not apply to the code that you add in this way.  To avoid misleading
+ * anyone as to the status of such modified files, you must delete
+ * this exception notice from them.
+ *
+ * If you write modifications of your own for GUILE, it is your choice
+ * whether to permit this exception to apply to your modifications.
+ * If you do not wish that, delete this exception notice.  */
+
+
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#ifdef __ia64__
+#include <ucontext.h>
+extern unsigned long * __libc_ia64_register_backing_store_base;
+#endif
+
+#include "libguile/_scm.h"
+#include "libguile/eval.h"
+#include "libguile/stime.h"
+#include "libguile/stackchk.h"
+#include "libguile/struct.h"
+#include "libguile/smob.h"
+#include "libguile/unif.h"
+#include "libguile/async.h"
+#include "libguile/ports.h"
+#include "libguile/root.h"
+#include "libguile/strings.h"
+#include "libguile/vectors.h"
+#include "libguile/weaks.h"
+#include "libguile/hashtab.h"
+#include "libguile/tags.h"
+
+#include "libguile/validate.h"
+#include "libguile/deprecation.h"
+#include "libguile/gc.h"
+
+#include "libguile/private-gc.h"
+
+#ifdef GUILE_DEBUG_MALLOC
+#include "libguile/debug-malloc.h"
+#endif
+
+#ifdef HAVE_MALLOC_H
+#include <malloc.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+/*
+  INIT_MALLOC_LIMIT is the initial amount of malloc usage which will
+  trigger a GC.
+  
+  After startup (at the guile> prompt), we have approximately 100k of
+  alloced memory, which won't go away on GC. Let's set the init such
+  that we get a nice yield on the next allocation:
+*/
+#define SCM_DEFAULT_INIT_MALLOC_LIMIT 200000
+#define SCM_DEFAULT_MALLOC_MINYIELD 40
+
+
+static int scm_i_minyield_malloc;
+
+void
+scm_gc_init_malloc (void)
+{
+  scm_mtrigger = scm_getenv_int ("GUILE_INIT_MALLOC_LIMIT",
+				 SCM_DEFAULT_INIT_MALLOC_LIMIT);
+  scm_i_minyield_malloc =  scm_getenv_int ("GUILE_MIN_YIELD_MALLOC",
+					   SCM_DEFAULT_MALLOC_MINYIELD);
+}
+
+
+
+/* Function for non-cell memory management.
+ */
+
+void *
+scm_malloc (size_t size)
+{
+  void *ptr;
+
+  if (size == 0)
+    return NULL;
+
+  SCM_SYSCALL (ptr = malloc (size));
+  if (ptr)
+    return ptr;
+
+  scm_i_sweep_all_segments ("malloc");
+  SCM_SYSCALL (ptr = malloc (size));
+  if (ptr)
+    return ptr;
+
+  scm_igc ("malloc");
+  scm_i_sweep_all_segments ("malloc/gc");
+
+  SCM_SYSCALL (ptr = malloc (size));
+  if (ptr)
+    return ptr;
+
+  scm_memory_error ("malloc");
+}
+
+void *
+scm_realloc (void *mem, size_t size)
+{
+  void *ptr;
+
+  SCM_SYSCALL (ptr = realloc (mem, size));
+  if (ptr)
+    return ptr;
+
+  scm_i_sweep_all_segments ("realloc");
+  
+  SCM_SYSCALL (ptr = realloc (mem, size));
+  if (ptr)
+    return ptr;
+
+  scm_igc ("realloc");
+  scm_i_sweep_all_segments ("realloc");
+  
+  SCM_SYSCALL (ptr = realloc (mem, size));
+  if (ptr)
+    return ptr;
+
+  scm_memory_error ("realloc");
+}
+
+char *
+scm_strndup (const char *str, size_t n)
+{
+  char *dst = scm_malloc (n+1);
+  memcpy (dst, str, n);
+  dst[n] = 0;
+  return dst;
+}
+
+char *
+scm_strdup (const char *str)
+{
+  return scm_strndup (str, strlen (str));
+}
+
+void
+scm_gc_register_collectable_memory (void *mem, size_t size, const char *what)
+{
+  scm_mallocated += size;
+
+  /*
+    we could finish the full sweep (without mark) here, but in
+    practice this turns out to be ineffective.
+   */
+
+  /*
+    A program that uses a lot of malloced collectable memory (vectors,
+    strings), will use a lot of memory off the cell-heap; it needs to
+    do GC more often (before cells are exhausted), otherwise swapping
+    and malloc management will tie it down.
+   */
+  if (scm_mallocated > scm_mtrigger)
+    {
+      long prev_alloced  = scm_mallocated;
+      float yield;
+      
+      scm_igc (what);
+      scm_i_sweep_all_segments("mtrigger");
+
+      yield  = (prev_alloced - scm_mallocated) / (float) prev_alloced;
+
+      /*
+      fprintf (stderr,  "prev %lud , now %lud, yield %4.2lf, want %d",
+	       prev_alloced, scm_mallocated, 100.0*yield, scm_i_minyield_malloc);
+      */
+
+      if (yield < scm_i_minyield_malloc /  100.0)
+	{
+	  /*
+	    We make the trigger a little larger, even; If you have a
+	    program that builds up a lot of data in strings, then the
+	    desired yield will never be satisfied.
+
+	    Instead of getting bogged down, we let the mtrigger grow
+	    strongly with it.
+	   */
+	  scm_mtrigger = (scm_mallocated * 110) / (100 - scm_i_minyield_malloc);
+	  
+	  /*
+	  fprintf (stderr, "Mtrigger sweep: ineffective. New trigger %d\n", scm_mtrigger);
+	  */
+
+	  
+	}
+    }
+  
+#ifdef GUILE_DEBUG_MALLOC
+  if (mem)
+    scm_malloc_register (mem, what);
+#endif
+}
+
+void
+scm_gc_unregister_collectable_memory (void *mem, size_t size, const char *what)
+{
+  scm_mallocated -= size;
+  scm_gc_malloc_collected += size;
+  
+#ifdef GUILE_DEBUG_MALLOC
+  if (mem)
+    scm_malloc_unregister (mem);
+#endif
+}
+
+void *
+scm_gc_malloc (size_t size, const char *what)
+{
+  /*
+    The straightforward implementation below has the problem
+     that it might call the GC twice, once in scm_malloc and then
+     again in scm_gc_register_collectable_memory.  We don't really
+     want the second GC since it will not find new garbage.
+
+
+     Note: this is a theoretical peeve. In reality, malloc() never
+     returns NULL. Usually, memory is overcommitted, and when you try
+     to write it the program is killed with signal 11. --hwn
+  */
+
+  void *ptr = scm_malloc (size);
+  scm_gc_register_collectable_memory (ptr, size, what);
+  return ptr;
+}
+
+void *
+scm_gc_realloc (void *mem, size_t old_size, size_t new_size, const char *what)
+{
+  /* XXX - see scm_gc_malloc. */
+
+  void *ptr = scm_realloc (mem, new_size);
+  scm_gc_unregister_collectable_memory (mem, old_size, what);
+  scm_gc_register_collectable_memory (ptr, new_size, what);
+  return ptr;
+}
+
+void
+scm_gc_free (void *mem, size_t size, const char *what)
+{
+  scm_gc_unregister_collectable_memory (mem, size, what);
+  free (mem);
+}
+
+char *
+scm_gc_strndup (const char *str, size_t n, const char *what)
+{
+  char *dst = scm_gc_malloc (n+1, what);
+  memcpy (dst, str, n);
+  dst[n] = 0;
+  return dst;
+}
+
+char *
+scm_gc_strdup (const char *str, const char *what)
+{
+  return scm_gc_strndup (str, strlen (str), what);
+}
+
+#if SCM_ENABLE_DEPRECATED == 1
+
+/* {Deprecated front end to malloc}
+ *
+ * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc,
+ * scm_done_free
+ *
+ * These functions provide services comparable to malloc, realloc, and
+ * free.  They should be used when allocating memory that will be under
+ * control of the garbage collector, i.e., if the memory may be freed
+ * during garbage collection.
+ *
+ * They are deprecated because they weren't really used the way
+ * outlined above, and making sure to return the right amount from
+ * smob free routines was sometimes difficult when dealing with nested
+ * data structures.  We basically want everybody to review their code
+ * and use the more symmetrical scm_gc_malloc/scm_gc_free functions
+ * instead.  In some cases, where scm_must_malloc has been used
+ * incorrectly (i.e. for non-GC-able memory), use scm_malloc/free.
+ */
+
+void *
+scm_must_malloc (size_t size, const char *what)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_must_malloc is deprecated.  "
+     "Use scm_gc_malloc and scm_gc_free instead.");
+
+  return scm_gc_malloc (size, what);
+}
+
+void *
+scm_must_realloc (void *where,
+		  size_t old_size,
+		  size_t size,
+		  const char *what)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_must_realloc is deprecated.  "
+     "Use scm_gc_realloc and scm_gc_free instead.");
+
+  return scm_gc_realloc (where, old_size, size, what);
+}
+
+char *
+scm_must_strndup (const char *str, size_t length)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_must_strndup is deprecated.  "
+     "Use scm_gc_strndup and scm_gc_free instead.");
+
+  return scm_gc_strndup (str, length, "string");
+}
+
+char *
+scm_must_strdup (const char *str)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_must_strdup is deprecated.  "
+     "Use scm_gc_strdup and scm_gc_free instead.");
+
+  return scm_gc_strdup (str, "string");
+}
+
+void
+scm_must_free (void *obj)
+#define FUNC_NAME "scm_must_free"
+{
+  scm_c_issue_deprecation_warning
+    ("scm_must_free is deprecated.  "
+     "Use scm_gc_malloc and scm_gc_free instead.");
+
+#ifdef GUILE_DEBUG_MALLOC
+  scm_malloc_unregister (obj);
+#endif
+  if (obj)
+    free (obj);
+  else
+    SCM_MISC_ERROR ("freeing NULL pointer", SCM_EOL);
+}
+#undef FUNC_NAME
+
+
+void
+scm_done_malloc (long size)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_done_malloc is deprecated.  "
+     "Use scm_gc_register_collectable_memory instead.");
+
+  scm_gc_register_collectable_memory (NULL, size, "foreign mallocs");
+}
+
+void
+scm_done_free (long size)
+{
+  scm_c_issue_deprecation_warning
+    ("scm_done_free is deprecated.  "
+     "Use scm_gc_unregister_collectable_memory instead.");
+
+  scm_gc_unregister_collectable_memory (NULL, size, "foreign mallocs");
+}
+
+#endif /* SCM_ENABLE_DEPRECATED == 1 */