libhurd-slab/

2005-01-06  Neal H. Walfield  <neal@gnu.org>

	* slab.h (hurd_slab_allocate_buffer_t): New type.
	(hurd_slab_deallocate_buffer_t): Likewise.
	(struct hurd_slab_space): New fields allocate_buffer and
	deallocate_buffer.
	(HURD_SLAB_SPACE_INITIALIZER): Add new arguments ALLOC and DEALLOC
	and take them into account when creating the slab.
	(hurd_slab_create): New parameters ALLOCATE_BUFFER and
	DEALLOCATE_BUFFER.
	(hurd_slab_init): Likewise.

	* slab.c (allocate_buffer): New function.
	(deallocate_buffer): Likewise.
	(reap): When deallocating a buffer, use allocate_buffer.
	(grow): When allocating or deallocating a buffer, call
	allocate_buffer or deallocate_buffer as appropriate.
	(hurd_slab_init): Add new arguments ALLOCATE_BUFFER and
	DEALLOCATE_BUFFER and take them into account when setting up
	SPACE.
	(hurd_slab_create): Likewise.

libhurd-cap/

2005-01-07  Neal H. Walfield  <neal@gnu.org>

	* cap.c (hurd_cap_init): Supply the allocate_buffer and
	deallocate_buffer arguments to hurd_slab_create to conform with
	the new semantics.

libhurd-cap-server/

2005-01-07  Neal H. Walfield  <neal@gnu.org>

	* class-init.c (hurd_cap_class_init_untyped): Supply the
	allocate_buffer and deallocate_buffer arguments to
	hurd_slab_create to conform with the new semantics.
	* obj-entry-space.c (_hurd_cap_obj_entry_space): Likewise for
	HURD_SLAB_SPACE_INITIALIZER.
	* client-create.c (_hurd_cap_client_space): Likewise.

task/

2005-01-07  Neal H. Walfield  <neal@gnu.org>

	* thread.c (threads): Supply the allocate_buffer and
	deallocate_buffer arguments to HURD_SLAB_SPACE_INITIALIZER to
	conform with the new semantics.

4 files changed, 116 insertions, 19 deletions

diff --git a/libhurd-slab/ChangeLog b/libhurd-slab/ChangeLog
index b1acb7e..378834f 100644
--- a/libhurd-slab/ChangeLog
+++ b/libhurd-slab/ChangeLog
@@ -1,3 +1,25 @@
+2005-01-06  Neal H. Walfield  <neal@gnu.org>
+
+	* slab.h (hurd_slab_allocate_buffer_t): New type.
+	(hurd_slab_deallocate_buffer_t): Likewise.
+	(struct hurd_slab_space): New fields allocate_buffer and
+	deallocate_buffer.
+	(HURD_SLAB_SPACE_INITIALIZER): Add new arguments ALLOC and DEALLOC
+	and take them into account when creating the slab.
+	(hurd_slab_create): New parameters ALLOCATE_BUFFER and
+	DEALLOCATE_BUFFER.
+	(hurd_slab_init): Likewise.
+
+	* slab.c (allocate_buffer): New function.
+	(deallocate_buffer): Likewise.
+	(reap): When deallocating a buffer, use allocate_buffer.
+	(grow): When allocating or deallocating a buffer, call
+	allocate_buffer or deallocate_buffer as appropriate.
+	(hurd_slab_init): Add new arguments ALLOCATE_BUFFER and
+	DEALLOCATE_BUFFER and take them into account when setting up
+	SPACE.
+	(hurd_slab_create): Likewise.
+
 2004-11-01  Marcus Brinkmann  <marcus@gnu.org>
 
 	* slab.c (hurd_slab_destroy): Remove unused variable PREVP.
diff --git a/libhurd-slab/README b/libhurd-slab/README
index 4d6e6d4..d171a73 100644
--- a/libhurd-slab/README
+++ b/libhurd-slab/README
@@ -7,8 +7,8 @@ purpose allocation strategy like malloc(), but a special arena (or
 other backing memory) and a special purpose allocator that can take
 advantage of the fact that all objects are of the same size.
 
-In addition, such objects usually have an initial stage that is
-naturally returned to when the object is not needed anymore.  For
+In addition, such objects usually have an initial stage that they
+naturally return to when the objects are no longer needed.  For
 example locks are unlocked, reference counters are zero, etc.  In such
 a situation, performance can be further increased by caching the
 unused objects, instead of destroying them.
diff --git a/libhurd-slab/slab.c b/libhurd-slab/slab.c
index c0a717c..b6e3f51 100644
--- a/libhurd-slab/slab.c
+++ b/libhurd-slab/slab.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2003, 2005 Free Software Foundation, Inc.
    Written by Johan Rydberg.
 
    This file is part of the GNU Hurd.
@@ -65,6 +65,40 @@ struct hurd_slab
   union hurd_bufctl *free_list;
 };
 
+/* Allocate a buffer in *PTR of size SIZE which must be a power of 2
+   and self aligned (i.e. aligned on a SIZE byte boundary) for slab
+   space SPACE.  Return 0 on success, an error code on failure.  */
+static error_t
+allocate_buffer (struct hurd_slab_space *space, size_t size, void **ptr)
+{
+  if (space->allocate_buffer)
+    return space->allocate_buffer (space->hook, getpagesize (), ptr);
+  else
+    {
+      *ptr = mmap (NULL, getpagesize (), PROT_READ|PROT_WRITE,
+		   MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+      if (*ptr == MAP_FAILED)
+	return errno;
+      else
+	return 0;
+    }
+}
+
+/* Deallocate buffer BUFFER of size SIZE which was allocated for slab
+   space SPACE.  Return 0 on success, an error code on failure.  */
+static error_t
+deallocate_buffer (struct hurd_slab_space *space, void *buffer, size_t size)
+{
+  if (space->deallocate_buffer)
+    return space->deallocate_buffer (space->hook, buffer, size);
+  else
+    {
+      if (munmap (buffer, size) == -1)
+	return errno;
+      else
+	return 0;
+    }
+}
 
 /* Insert SLAB into the list of slabs in SPACE.  SLAB is expected to
    be complete (so it will be inserted at the end).  */
@@ -143,9 +177,9 @@ reap (struct hurd_slab_space *space)
 	     in front of it), get address by masking with page size.  
 	     This frees the slab and all its buffers, since they live on
 	     the same page.  */
-	  err = munmap 
-	    ((void *) (((uintptr_t) s) & ~(getpagesize () - 1)),
-	     getpagesize ());
+	  err = deallocate_buffer (space, (void *) (((uintptr_t) s)
+						    & ~(getpagesize () - 1)),
+				   getpagesize ());
 	  if (err)
 	    break;
 	  __hurd_slab_nr_pages--;
@@ -200,6 +234,7 @@ init_space (hurd_slab_space_t space)
 static error_t
 grow (struct hurd_slab_space *space)
 {
+  error_t err;
   struct hurd_slab *new_slab;
   union hurd_bufctl *bufctl;
   int nr_objs, i;
@@ -211,10 +246,10 @@ grow (struct hurd_slab_space *space)
   if (!space->initialized)
     init_space (space);
 
-  p = mmap (NULL, getpagesize (), PROT_READ|PROT_WRITE,
-	    MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
-  if (p == MAP_FAILED)
-    return errno;
+  err = allocate_buffer (space, getpagesize (), &p);
+  if (err)
+    return err;
+
   __hurd_slab_nr_pages++;
 
   new_slab = (p + getpagesize () - sizeof (struct hurd_slab));
@@ -244,7 +279,7 @@ grow (struct hurd_slab_space *space)
 		  (*space->destructor) (space->hook, buffer);
 		}
 
-	      munmap (p, getpagesize ());
+	      deallocate_buffer (space, p, getpagesize ());
 	      return err;
 	    }
 	}
@@ -270,6 +305,8 @@ grow (struct hurd_slab_space *space)
 /* Initialize the slab space SPACE.  */
 error_t
 hurd_slab_init (hurd_slab_space_t space, size_t size, size_t alignment,
+		hurd_slab_allocate_buffer_t allocate_buffer,
+		hurd_slab_deallocate_buffer_t deallocate_buffer,
 		hurd_slab_constructor_t constructor,
 		hurd_slab_destructor_t destructor,
 		void *hook)
@@ -299,6 +336,8 @@ hurd_slab_init (hurd_slab_space_t space, size_t size, size_t alignment,
   if (err)
     return err;
 
+  space->allocate_buffer = allocate_buffer;
+  space->deallocate_buffer = deallocate_buffer;
   space->constructor = constructor;
   space->destructor = destructor;
   space->hook = hook;
@@ -312,6 +351,8 @@ hurd_slab_init (hurd_slab_space_t space, size_t size, size_t alignment,
    constructor and destructor.  ALIGNMENT can be zero.  */
 error_t
 hurd_slab_create (size_t size, size_t alignment,
+		  hurd_slab_allocate_buffer_t allocate_buffer,
+		  hurd_slab_deallocate_buffer_t deallocate_buffer,
 		  hurd_slab_constructor_t constructor,
 		  hurd_slab_destructor_t destructor,
 		  void *hook,
@@ -324,7 +365,9 @@ hurd_slab_create (size_t size, size_t alignment,
   if (!space)
     return ENOMEM;
 
-  err = hurd_slab_init (space, size, alignment, constructor, destructor, hook);
+  err = hurd_slab_init (space, size, alignment,
+			allocate_buffer, deallocate_buffer,
+			constructor, destructor, hook);
   if (err)
     {
       free (space);
diff --git a/libhurd-slab/slab.h b/libhurd-slab/slab.h
index 5154943..3fa854c 100644
--- a/libhurd-slab/slab.h
+++ b/libhurd-slab/slab.h
@@ -1,5 +1,5 @@
 /* slab.h - The GNU Hurd slab allocator interface.
-   Copyright (C) 2003 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2005 Free Software Foundation, Inc.
    Written by Marcus Brinkmann <marcus@gnu.org>
 
    This file is part of the GNU Hurd.
@@ -27,6 +27,18 @@
 #include <pthread.h>
 
 
+/* Allocate a buffer in *PTR of size SIZE which must be a power of 2
+   and self aligned (i.e. aligned on a SIZE byte boundary).  HOOK is
+   as provided to hurd_slab_create.  Return 0 on success, an error
+   code on failure.  */
+typedef error_t (*hurd_slab_allocate_buffer_t) (void *hook, size_t size,
+						void **ptr);
+
+/* Deallocate buffer BUFFER of size SIZE.  HOOK is as provided to
+   hurd_slab_create.  */
+typedef error_t (*hurd_slab_deallocate_buffer_t) (void *hook, void *buffer,
+						  size_t size);
+
 /* Initialize the slab object pointed to by BUFFER.  HOOK is as
    provided to hurd_slab_create.  */
 typedef error_t (*hurd_slab_constructor_t) (void *hook, void *buffer);
@@ -63,6 +75,12 @@ struct hurd_slab_space
   size_t requested_size;
   size_t requested_align;
 
+  /* The buffer allocator.  */
+  hurd_slab_allocate_buffer_t allocate_buffer;
+
+  /* The buffer deallocator.  */
+  hurd_slab_deallocate_buffer_t deallocate_buffer;
+
   /* The constructor.  */
   hurd_slab_constructor_t constructor;
 
@@ -94,15 +112,21 @@ struct hurd_slab_space
 
 
 /* Static initializer.  TYPE is used to get size and alignment of
-   objects the slab space will be used to allocate.  CTOR and DTOR is
-   constructor and destructor, respectivly.  HOOK is passed as user
-   data to the constructor and destructor.  */
-#define HURD_SLAB_SPACE_INITIALIZER(TYPE, CTOR, DTOR, HOOK) 	\
+   objects the slab space will be used to allocate.  ALLOCATE_BUFFER
+   may be NULL in which case mmap is called.  DEALLOCATE_BUFFER may be
+   NULL in which case munmap is called.  CTOR and DTOR are the slab's
+   object constructor and destructor, respectivly and may be NULL if
+   not required.  HOOK is passed as user data to the constructor and
+   destructor.  */
+#define HURD_SLAB_SPACE_INITIALIZER(TYPE, ALLOC, DEALLOC, CTOR,	\
+				    DTOR, HOOK)			\
   {								\
     false,							\
     PTHREAD_MUTEX_INITIALIZER, 					\
     sizeof (TYPE),						\
     __alignof__ (TYPE),						\
+    ALLOC,							\
+    DEALLOC,							\
     CTOR,							\
     DTOR,							\
     HOOK							\
@@ -112,9 +136,15 @@ struct hurd_slab_space
 
 
 /* Create a new slab space with the given object size, alignment,
-   constructor and destructor.  ALIGNMENT can be zero.  HOOK is passed
-   as the first argument to the constructor and destructor.  */
+   constructor and destructor.  ALIGNMENT can be zero.
+   ALLOCATE_BUFFER may be NULL in which case mmap is called.
+   DEALLOCATE_BUFFER may be NULL in which case munmap is called.  CTOR
+   and DTOR are the slabs object constructor and destructor,
+   respectivly and may be NULL if not required.  HOOK is passed as the
+   first argument to the constructor and destructor.  */
 error_t hurd_slab_create (size_t size, size_t alignment,
+			  hurd_slab_allocate_buffer_t allocate_buffer,
+			  hurd_slab_deallocate_buffer_t deallocate_buffer,
 			  hurd_slab_constructor_t constructor,
 			  hurd_slab_destructor_t destructor,
 			  void *hook,
@@ -122,6 +152,8 @@ error_t hurd_slab_create (size_t size, size_t alignment,
 
 /* Like hurd_slab_create, but does not allocate storage for the slab.  */
 error_t hurd_slab_init (hurd_slab_space_t space, size_t size, size_t alignment,
+			hurd_slab_allocate_buffer_t allocate_buffer,
+			hurd_slab_deallocate_buffer_t deallocate_buffer,
 			hurd_slab_constructor_t constructor,
 			hurd_slab_destructor_t destructor,
 			void *hook);