4 files changed, 113 insertions, 3 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 2ba43c4a5b07..03c2c24b9083 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -13,6 +13,10 @@ config GENERIC_FIND_FIRST_BIT
 config GENERIC_FIND_NEXT_BIT
         bool
 
+config GENERIC_FIND_LAST_BIT
+        bool
+        default y
+
 config CRC_CCITT
         tristate "CRC-CCITT functions"
         help
@@ -166,4 +170,8 @@ config CPUMASK_OFFSTACK
           them on the stack.  This is a bit more expensive, but avoids
           stack overflow.
 
+config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
+       bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
+       depends on EXPERIMENTAL && BROKEN
+
 endmenu
diff --git a/lib/Makefile b/lib/Makefile
index 80fe8a3ec12a..32b0e64ded27 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -37,6 +37,7 @@ lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
 lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
 lib-$(CONFIG_GENERIC_FIND_FIRST_BIT) += find_next_bit.o
 lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
+lib-$(CONFIG_GENERIC_FIND_LAST_BIT) += find_last_bit.o
 obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
 obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
 obj-$(CONFIG_PLIST) += plist.o
diff --git a/lib/cpumask.c b/lib/cpumask.c
index 8d03f22c6ced..3389e2440da0 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -76,15 +76,28 @@ int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
 
 /* These are not inline because of header tangles. */
 #ifdef CONFIG_CPUMASK_OFFSTACK
-bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+/**
+ * alloc_cpumask_var_node - allocate a struct cpumask on a given node
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ * @flags: GFP_ flags
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop returning a constant 1 (in <linux/cpumask.h>)
+ * Returns TRUE if memory allocation succeeded, FALSE otherwise.
+ *
+ * In addition, mask will be NULL if this fails.  Note that gcc is
+ * usually smart enough to know that mask can never be NULL if
+ * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case
+ * too.
+ */
+bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
 {
         if (likely(slab_is_available()))
-                *mask = kmalloc(cpumask_size(), flags);
+                *mask = kmalloc_node(cpumask_size(), flags, node);
         else {
 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
                 printk(KERN_ERR
                         "=> alloc_cpumask_var: kmalloc not available!\n");
-                dump_stack();
 #endif
                 *mask = NULL;
         }
@@ -94,21 +107,64 @@ bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
                 dump_stack();
         }
 #endif
+        /* FIXME: Bandaid to save us from old primitives which go to NR_CPUS. */
+        if (*mask) {
+                unsigned int tail;
+                tail = BITS_TO_LONGS(NR_CPUS - nr_cpumask_bits) * sizeof(long);
+                memset(cpumask_bits(*mask) + cpumask_size() - tail,
+                       0, tail);
+        }
+
         return *mask != NULL;
 }
+EXPORT_SYMBOL(alloc_cpumask_var_node);
+
+/**
+ * alloc_cpumask_var - allocate a struct cpumask
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ * @flags: GFP_ flags
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop returning a constant 1 (in <linux/cpumask.h>).
+ *
+ * See alloc_cpumask_var_node.
+ */
+bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+        return alloc_cpumask_var_node(mask, flags, numa_node_id());
+}
 EXPORT_SYMBOL(alloc_cpumask_var);
 
+/**
+ * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena.
+ * @mask: pointer to cpumask_var_t where the cpumask is returned
+ *
+ * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
+ * a nop (in <linux/cpumask.h>).
+ * Either returns an allocated (zero-filled) cpumask, or causes the
+ * system to panic.
+ */
 void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
 {
         *mask = alloc_bootmem(cpumask_size());
 }
 
+/**
+ * free_cpumask_var - frees memory allocated for a struct cpumask.
+ * @mask: cpumask to free
+ *
+ * This is safe on a NULL mask.
+ */
 void free_cpumask_var(cpumask_var_t mask)
 {
         kfree(mask);
 }
 EXPORT_SYMBOL(free_cpumask_var);
 
+/**
+ * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var
+ * @mask: cpumask to free
+ */
 void __init free_bootmem_cpumask_var(cpumask_var_t mask)
 {
         free_bootmem((unsigned long)mask, cpumask_size());
diff --git a/lib/find_last_bit.c b/lib/find_last_bit.c
new file mode 100644
index 000000000000..5d202e36bdd8
--- /dev/null
+++ b/lib/find_last_bit.c
@@ -0,0 +1,45 @@
+/* find_last_bit.c: fallback find next bit implementation
+ *
+ * Copyright (C) 2008 IBM Corporation
+ * Written by Rusty Russell <rusty@rustcorp.com.au>
+ * (Inspired by David Howell's find_next_bit implementation)
+ *
+ * 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 of the License, or (at your option) any later version.
+ */
+
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <asm/types.h>
+#include <asm/byteorder.h>
+
+unsigned long find_last_bit(const unsigned long *addr, unsigned long size)
+{
+        unsigned long words;
+        unsigned long tmp;
+
+        /* Start at final word. */
+        words = size / BITS_PER_LONG;
+
+        /* Partial final word? */
+        if (size & (BITS_PER_LONG-1)) {
+                tmp = (addr[words] & (~0UL >> (BITS_PER_LONG
+                                         - (size & (BITS_PER_LONG-1)))));
+                if (tmp)
+                        goto found;
+        }
+
+        while (words) {
+                tmp = addr[--words];
+                if (tmp) {
+found:
+                        return words * BITS_PER_LONG + __fls(tmp);
+                }
+        }
+
+        /* Not found */
+        return size;
+}
+EXPORT_SYMBOL(find_last_bit);