Implement UMA_MD_SMALL_ALLOC, since the BAT registers allow direct

addressing of memory. Makes a substantial improvement for apps that
stress the limited amount of KVM on PPC (e.g. untarring the ports tree).

uma_machdep.c stolen from amd64/ia64.

sys/conf/files.powerpc

@@ -58,6 +58,7 @@ powerpc/powerpc/syncicache.c	standard
 powerpc/powerpc/sys_machdep.c	standard
 powerpc/powerpc/swtch.S		standard
 powerpc/powerpc/trap.c		standard
+powerpc/powerpc/uma_machdep.c	standard
 powerpc/powerpc/vm_machdep.c	standard
 
 powerpc/powerpc/db_disasm.c	optional	ddb

sys/powerpc/aim/uma_machdep.c

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2003 The FreeBSD Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/systm.h>
+#include <vm/vm.h>
+#include <vm/vm_page.h>
+#include <vm/vm_pageout.h>
+#include <vm/uma.h>
+#include <vm/uma_int.h>
+#include <machine/vmparam.h>
+
+void *
+uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
+{
+	static vm_pindex_t color;
+	void *va;
+	vm_page_t m;
+	int pflags;
+
+	*flags = UMA_SLAB_PRIV;
+	if ((wait & (M_NOWAIT|M_USE_RESERVE)) == M_NOWAIT)
+		pflags = VM_ALLOC_INTERRUPT;
+	else
+		pflags = VM_ALLOC_SYSTEM;
+	if (wait & M_ZERO)
+		pflags |= VM_ALLOC_ZERO;
+
+	for (;;) {
+		m = vm_page_alloc(NULL, color++, pflags | VM_ALLOC_NOOBJ);
+		if (m == NULL) {
+			if (wait & M_NOWAIT)
+				return (NULL);
+			VM_WAIT;
+		} else
+			break;
+	}
+
+	va = (void *) VM_PAGE_TO_PHYS(m);
+	if ((wait & M_ZERO) && (m->flags & PG_ZERO) == 0)
+		bzero(va, PAGE_SIZE);
+	return (va);
+}
+
+void
+uma_small_free(void *mem, int size, u_int8_t flags)
+{
+	vm_page_t m;
+
+	m = PHYS_TO_VM_PAGE((u_int32_t)mem);
+	vm_page_lock_queues();
+	vm_page_free(m);
+	vm_page_unlock_queues();
+}

sys/powerpc/include/vmparam.h

@@ -81,6 +81,12 @@
  */
 #define	MAXSLP 		20
 
+/*
+ * Use the direct-mapped BAT registers for UMA small allocs. This
+ * takes pressure off the small amount of available KVA.
+ */
+#define UMA_MD_SMALL_ALLOC
+
 /*
  * Would like to have MAX addresses = 0, but this doesn't (currently) work
  */

sys/powerpc/powerpc/uma_machdep.c

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2003 The FreeBSD Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/systm.h>
+#include <vm/vm.h>
+#include <vm/vm_page.h>
+#include <vm/vm_pageout.h>
+#include <vm/uma.h>
+#include <vm/uma_int.h>
+#include <machine/vmparam.h>
+
+void *
+uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
+{
+	static vm_pindex_t color;
+	void *va;
+	vm_page_t m;
+	int pflags;
+
+	*flags = UMA_SLAB_PRIV;
+	if ((wait & (M_NOWAIT|M_USE_RESERVE)) == M_NOWAIT)
+		pflags = VM_ALLOC_INTERRUPT;
+	else
+		pflags = VM_ALLOC_SYSTEM;
+	if (wait & M_ZERO)
+		pflags |= VM_ALLOC_ZERO;
+
+	for (;;) {
+		m = vm_page_alloc(NULL, color++, pflags | VM_ALLOC_NOOBJ);
+		if (m == NULL) {
+			if (wait & M_NOWAIT)
+				return (NULL);
+			VM_WAIT;
+		} else
+			break;
+	}
+
+	va = (void *) VM_PAGE_TO_PHYS(m);
+	if ((wait & M_ZERO) && (m->flags & PG_ZERO) == 0)
+		bzero(va, PAGE_SIZE);
+	return (va);
+}
+
+void
+uma_small_free(void *mem, int size, u_int8_t flags)
+{
+	vm_page_t m;
+
+	m = PHYS_TO_VM_PAGE((u_int32_t)mem);
+	vm_page_lock_queues();
+	vm_page_free(m);
+	vm_page_unlock_queues();
+}