patch-2.4.27 linux-2.4.27/fs/xfs/linux-2.4/kmem.c

• Lines: 186
• Date: 2004-08-07 16:26:06.061404591 -0700
• Orig file: linux-2.4.26/fs/xfs/linux-2.4/kmem.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.26/fs/xfs/linux-2.4/kmem.c linux-2.4.27/fs/xfs/linux-2.4/kmem.c
@@ -0,0 +1,185 @@
+/*
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/swap.h>
+
+#include "time.h"
+#include "kmem.h"
+
+#define MAX_VMALLOCS	6
+#define MAX_SLAB_SIZE	0x20000
+#define MAX_SHAKE	8
+
+static kmem_shake_func_t	shake_list[MAX_SHAKE];
+static DECLARE_MUTEX(shake_sem);
+
+/*
+ * Old-school memory shaking for vanilla 2.4 kernels (which
+ * have no VM shake callback/registration infrastructure).
+ */
+
+kmem_shaker_t
+kmem_shake_register(kmem_shake_func_t sfunc)
+{
+	int	i;
+
+	down(&shake_sem);
+	for (i = 0; i < MAX_SHAKE; i++) {
+		if (shake_list[i] == NULL) {
+			shake_list[i] = sfunc;
+			break;
+		}
+	}
+	if (i == MAX_SHAKE)
+		BUG();
+	up(&shake_sem);
+
+	return (kmem_shaker_t)sfunc;
+}
+
+void
+kmem_shake_deregister(kmem_shaker_t sfunc)
+{
+	int	i;
+
+	down(&shake_sem);
+	for (i = 0; i < MAX_SHAKE; i++) {
+		if (shake_list[i] == (kmem_shake_func_t)sfunc)
+			break;
+	}
+	if (i == MAX_SHAKE)
+		BUG();
+	for (; i < MAX_SHAKE - 1; i++) {
+		shake_list[i] = shake_list[i+1];
+	}
+	shake_list[i] = NULL;
+	up(&shake_sem);
+}
+
+static __inline__ void kmem_shake(void)
+{
+	int	i;
+
+	down(&shake_sem);
+	for (i = 0; i < MAX_SHAKE && shake_list[i]; i++)
+		(*shake_list[i])(0, 0);
+	up(&shake_sem);
+	delay(10);
+}
+
+void *
+kmem_alloc(size_t size, int flags)
+{
+	int	retries = 0, lflags = kmem_flags_convert(flags);
+	void	*ptr;
+
+	do {
+		if (size < MAX_SLAB_SIZE || retries > MAX_VMALLOCS)
+			ptr = kmalloc(size, lflags);
+		else
+			ptr = __vmalloc(size, lflags, PAGE_KERNEL);
+		if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
+			return ptr;
+		kmem_shake();
+		if (!(++retries % 100))
+			printk(KERN_ERR "possible deadlock in %s (mode:0x%x)\n",
+					__FUNCTION__, lflags);
+	} while (1);
+}
+
+void *
+kmem_zalloc(size_t size, int flags)
+{
+	void	*ptr;
+
+	ptr = kmem_alloc(size, flags);
+	if (ptr)
+		memset((char *)ptr, 0, (int)size);
+	return ptr;
+}
+
+void
+kmem_free(void *ptr, size_t size)
+{
+	if (((unsigned long)ptr < VMALLOC_START) ||
+	    ((unsigned long)ptr >= VMALLOC_END)) {
+		kfree(ptr);
+	} else {
+		vfree(ptr);
+	}
+}
+
+void *
+kmem_realloc(void *ptr, size_t newsize, size_t oldsize, int flags)
+{
+	void	*new;
+
+	new = kmem_alloc(newsize, flags);
+	if (ptr) {
+		if (new)
+			memcpy(new, ptr,
+				((oldsize < newsize) ? oldsize : newsize));
+		kmem_free(ptr, oldsize);
+	}
+	return new;
+}
+
+void *
+kmem_zone_alloc(kmem_zone_t *zone, int flags)
+{
+	int	retries = 0, lflags = kmem_flags_convert(flags);
+	void	*ptr;
+
+	do {
+		ptr = kmem_cache_alloc(zone, lflags);
+		if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
+			return ptr;
+		kmem_shake();
+		if (!(++retries % 100))
+			printk(KERN_ERR "possible deadlock in %s (mode:0x%x)\n",
+					__FUNCTION__, lflags);
+	} while (1);
+}
+
+void *
+kmem_zone_zalloc(kmem_zone_t *zone, int flags)
+{
+	void	*ptr;
+
+	ptr = kmem_zone_alloc(zone, flags);
+	if (ptr)
+		memset((char *)ptr, 0, kmem_cache_size(zone));
+	return ptr;
+}