make sort() generally available

Rather than having this general library function only on ia64, move it
into common code, to be used by x86 exception table sorting too.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

8 files changed, 93 insertions, 135 deletions

diff --git a/xen/arch/ia64/linux-xen/Makefile b/xen/arch/ia64/linux-xen/Makefile
index 8e1bb1c907..b2f207db84 100644
--- a/xen/arch/ia64/linux-xen/Makefile
+++ b/xen/arch/ia64/linux-xen/Makefile
@@ -12,7 +12,6 @@ obj-y += sal.o
 obj-y += setup.o
 obj-y += smpboot.o
 obj-y += smp.o
-obj-y += sort.o
 obj-y += time.o
 obj-y += tlb.o
 obj-y += unaligned.o
diff --git a/xen/arch/ia64/linux-xen/README.origin b/xen/arch/ia64/linux-xen/README.origin
index b4e4d1b32b..98aa152852 100644
--- a/xen/arch/ia64/linux-xen/README.origin
+++ b/xen/arch/ia64/linux-xen/README.origin
@@ -21,7 +21,6 @@ sal.c			-> linux/arch/ia64/kernel/sal.c
 setup.c			-> linux/arch/ia64/kernel/setup.c
 smp.c			-> linux/arch/ia64/kernel/smp.c
 smpboot.c		-> linux/arch/ia64/kernel/smpboot.c
-sort.c			-> linux/lib/sort.c
 time.c			-> linux/arch/ia64/kernel/time.c
 tlb.c			-> linux/arch/ia64/mm/tlb.c
 unaligned.c		-> linux/arch/ia64/kernel/unaligned.c
diff --git a/xen/arch/ia64/linux-xen/sort.c b/xen/arch/ia64/linux-xen/sort.c
deleted file mode 100644
index 2b098c37d0..0000000000
--- a/xen/arch/ia64/linux-xen/sort.c
+++ /dev/null
@@ -1,122 +0,0 @@
-/*
- * A fast, small, non-recursive O(nlog n) sort for the Linux kernel
- *
- * Jan 23 2005  Matt Mackall <mpm@selenic.com>
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#ifdef XEN
-#include <linux/types.h>
-#endif
-
-void u32_swap(void *a, void *b, int size)
-{
-	u32 t = *(u32 *)a;
-	*(u32 *)a = *(u32 *)b;
-	*(u32 *)b = t;
-}
-
-void generic_swap(void *a, void *b, int size)
-{
-	char t;
-
-	do {
-		t = *(char *)a;
-		*(char *)a++ = *(char *)b;
-		*(char *)b++ = t;
-	} while (--size > 0);
-}
-
-/*
- * sort - sort an array of elements
- * @base: pointer to data to sort
- * @num: number of elements
- * @size: size of each element
- * @cmp: pointer to comparison function
- * @swap: pointer to swap function or NULL
- *
- * This function does a heapsort on the given array. You may provide a
- * swap function optimized to your element type.
- *
- * Sorting time is O(n log n) both on average and worst-case. While
- * qsort is about 20% faster on average, it suffers from exploitable
- * O(n*n) worst-case behavior and extra memory requirements that make
- * it less suitable for kernel use.
- */
-
-void sort(void *base, size_t num, size_t size,
-	  int (*cmp)(const void *, const void *),
-	  void (*swap)(void *, void *, int size))
-{
-	/* pre-scale counters for performance */
-	int i = (num/2) * size, n = num * size, c, r;
-
-	if (!swap)
-		swap = (size == 4 ? u32_swap : generic_swap);
-
-	/* heapify */
-	for ( ; i >= 0; i -= size) {
-		for (r = i; r * 2 < n; r  = c) {
-			c = r * 2;
-			if (c < n - size && cmp(base + c, base + c + size) < 0)
-				c += size;
-			if (cmp(base + r, base + c) >= 0)
-				break;
-			swap(base + r, base + c, size);
-		}
-	}
-
-	/* sort */
-	for (i = n - size; i >= 0; i -= size) {
-		swap(base, base + i, size);
-		for (r = 0; r * 2 < i; r = c) {
-			c = r * 2;
-			if (c < i - size && cmp(base + c, base + c + size) < 0)
-				c += size;
-			if (cmp(base + r, base + c) >= 0)
-				break;
-			swap(base + r, base + c, size);
-		}
-	}
-}
-
-EXPORT_SYMBOL(sort);
-
-#if 0
-/* a simple boot-time regression test */
-
-int cmpint(const void *a, const void *b)
-{
-	return *(int *)a - *(int *)b;
-}
-
-static int sort_test(void)
-{
-	int *a, i, r = 1;
-
-	a = kmalloc(1000 * sizeof(int), GFP_KERNEL);
-	BUG_ON(!a);
-
-	printk("testing sort()\n");
-
-	for (i = 0; i < 1000; i++) {
-		r = (r * 725861) % 6599;
-		a[i] = r;
-	}
-
-	sort(a, 1000, sizeof(int), cmpint, NULL);
-
-	for (i = 0; i < 999; i++)
-		if (a[i] > a[i+1]) {
-			printk("sort() failed!\n");
-			break;
-		}
-
-	kfree(a);
-
-	return 0;
-}
-
-module_init(sort_test);
-#endif
diff --git a/xen/common/Makefile b/xen/common/Makefile
index b792631483..2630e88c31 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -22,6 +22,7 @@ obj-y += sched_arinc653.o
 obj-y += schedule.o
 obj-y += shutdown.o
 obj-y += softirq.o
+obj-y += sort.o
 obj-y += spinlock.o
 obj-y += stop_machine.o
 obj-y += string.o
diff --git a/xen/common/sort.c b/xen/common/sort.c
new file mode 100644
index 0000000000..d96fc2af18
--- /dev/null
+++ b/xen/common/sort.c
@@ -0,0 +1,82 @@
+/*
+ * A fast, small, non-recursive O(nlog n) sort for the Linux kernel
+ *
+ * Jan 23 2005  Matt Mackall <mpm@selenic.com>
+ */
+
+#include <xen/types.h>
+
+static void u32_swap(void *a, void *b, int size)
+{
+    u32 t = *(u32 *)a;
+    *(u32 *)a = *(u32 *)b;
+    *(u32 *)b = t;
+}
+
+static void generic_swap(void *a, void *b, int size)
+{
+    char t;
+
+    do {
+        t = *(char *)a;
+        *(char *)a++ = *(char *)b;
+        *(char *)b++ = t;
+    } while ( --size > 0 );
+}
+
+/*
+ * sort - sort an array of elements
+ * @base: pointer to data to sort
+ * @num: number of elements
+ * @size: size of each element
+ * @cmp: pointer to comparison function
+ * @swap: pointer to swap function or NULL
+ *
+ * This function does a heapsort on the given array. You may provide a
+ * swap function optimized to your element type.
+ *
+ * Sorting time is O(n log n) both on average and worst-case. While
+ * qsort is about 20% faster on average, it suffers from exploitable
+ * O(n*n) worst-case behavior and extra memory requirements that make
+ * it less suitable for kernel use.
+ */
+
+void sort(void *base, size_t num, size_t size,
+          int (*cmp)(const void *, const void *),
+          void (*swap)(void *, void *, int size))
+{
+    /* pre-scale counters for performance */
+    int i = (num/2) * size, n = num * size, c, r;
+
+    if (!swap)
+        swap = (size == 4 ? u32_swap : generic_swap);
+
+    /* heapify */
+    for ( ; i >= 0; i -= size )
+    {
+        for ( r = i; r * 2 < n; r  = c )
+        {
+            c = r * 2;
+            if ( (c < n - size) && (cmp(base + c, base + c + size) < 0) )
+                c += size;
+            if ( cmp(base + r, base + c) >= 0 )
+                break;
+            swap(base + r, base + c, size);
+        }
+    }
+
+    /* sort */
+    for ( i = n - size; i >= 0; i -= size )
+    {
+        swap(base, base + i, size);
+        for ( r = 0; r * 2 < i; r = c )
+        {
+            c = r * 2;
+            if ( (c < i - size) && (cmp(base + c, base + c + size) < 0) )
+                c += size;
+            if ( cmp(base + r, base + c) >= 0 )
+                break;
+            swap(base + r, base + c, size);
+        }
+    }
+}
diff --git a/xen/include/asm-ia64/linux/README.origin b/xen/include/asm-ia64/linux/README.origin
index b775b92728..527c2d3292 100644
--- a/xen/include/asm-ia64/linux/README.origin
+++ b/xen/include/asm-ia64/linux/README.origin
@@ -16,7 +16,6 @@ notifier.h		-> linux/include/linux/notifier.h
 percpu.h		-> linux/include/linux/percpu.h
 preempt.h		-> linux/include/linux/preempt.h
 seqlock.h		-> linux/include/linux/seqlock.h
-sort.h			-> linux/include/linux/sort.h
 stddef.h		-> linux/include/linux/stddef.h
 thread_info.h		-> linux/include/linux/thread_info.h
 time.h			-> linux/include/linux/time.h
diff --git a/xen/include/asm-ia64/linux/sort.h b/xen/include/asm-ia64/linux/sort.h
deleted file mode 100644
index d534da2b55..0000000000
--- a/xen/include/asm-ia64/linux/sort.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef _LINUX_SORT_H
-#define _LINUX_SORT_H
-
-#include <linux/types.h>
-
-void sort(void *base, size_t num, size_t size,
-	  int (*cmp)(const void *, const void *),
-	  void (*swap)(void *, void *, int));
-
-#endif
diff --git a/xen/include/xen/sort.h b/xen/include/xen/sort.h
new file mode 100644
index 0000000000..ec89c3aed4
--- /dev/null
+++ b/xen/include/xen/sort.h
@@ -0,0 +1,10 @@
+#ifndef __XEN_SORT_H__
+#define __XEN_SORT_H__
+
+#include <xen/types.h>
+
+void sort(void *base, size_t num, size_t size,
+          int (*cmp)(const void *, const void *),
+          void (*swap)(void *, void *, int));
+
+#endif /* __XEN_SORT_H__ */