From 27218d0c2b46fedde86906f08f68f783fa20f94d Mon Sep 17 00:00:00 2001
From: Mike Travis <travis@sgi.com>
Date: Fri, 18 Jul 2008 18:11:33 -0700
Subject: [PATCH] --- yaml --- r: 105232 b: refs/heads/master c:
 80422d3431cc990b967da129f9eb8e3e9989f841 h: refs/heads/master v: v3

---
 [refs]                        |  2 +-
 trunk/include/linux/cpumask.h | 33 ++++++++++++++++++++++++++-------
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/[refs] b/[refs]
index ce4bb2bceeca..e8a25498bedc 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b38868aabeeb9c0c76a41ac5fa98c24bf0096f2a
+refs/heads/master: 80422d3431cc990b967da129f9eb8e3e9989f841
diff --git a/trunk/include/linux/cpumask.h b/trunk/include/linux/cpumask.h
index 72f9c32c12b0..30d59d1d0626 100644
--- a/trunk/include/linux/cpumask.h
+++ b/trunk/include/linux/cpumask.h
@@ -75,16 +75,36 @@
  * CPU_MASK_NONE			Initializer - no bits set
  * unsigned long *cpus_addr(mask)	Array of unsigned long's in mask
  *
+ * CPUMASK_ALLOC kmalloc's a structure that is a composite of many cpumask_t
+ * variables, and CPUMASK_PTR provides pointers to each field.
+ *
+ * The structure should be defined something like this:
+ * struct my_cpumasks {
+ *	cpumask_t mask1;
+ *	cpumask_t mask2;
+ * };
+ *
+ * Usage is then:
+ *	CPUMASK_ALLOC(my_cpumasks);
+ *	CPUMASK_PTR(mask1, my_cpumasks);
+ *	CPUMASK_PTR(mask2, my_cpumasks);
+ *
+ *	--- DO NOT reference cpumask_t pointers until this check ---
+ *	if (my_cpumasks == NULL)
+ *		"kmalloc failed"...
+ *
+ * References are now pointers to the cpumask_t variables (*mask1, ...)
+ *
  *if NR_CPUS > BITS_PER_LONG
  *   CPUMASK_ALLOC(m)			Declares and allocates struct m *m =
- *					   (struct m *)kmalloc(sizeof(*m), ...)
- *   CPUMASK_FREE(m)			Macro for kfree(v)
+ *						kmalloc(sizeof(*m), GFP_KERNEL)
+ *   CPUMASK_FREE(m)			Macro for kfree(m)
  *else
  *   CPUMASK_ALLOC(m)			Declares struct m _m, *m = &_m
  *   CPUMASK_FREE(m)			Nop
  *endif
- *   CPUMASK_VAR(v, m)			Declares cpumask_t *v =
- *						m + offset(struct m, v)
+ *   CPUMASK_PTR(v, m)			Declares cpumask_t *v = &(m->v)
+ * ------------------------------------------------------------------------
  *
  * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
  * int cpumask_parse_user(ubuf, ulen, mask)	Parse ascii string as cpumask
@@ -326,11 +346,10 @@ extern cpumask_t cpu_mask_all;
 #define	CPUMASK_ALLOC(m)	struct m *m = kmalloc(sizeof(*m), GFP_KERNEL)
 #define	CPUMASK_FREE(m)		kfree(m)
 #else
-#define	CPUMASK_ALLOC(m)	struct allmasks _m, *m = &_m
+#define	CPUMASK_ALLOC(m)	struct m _m, *m = &_m
 #define	CPUMASK_FREE(m)
 #endif
-#define	CPUMASK_VAR(v, m) 	cpumask_t *v = (cpumask_t *)		\
-				((unsigned long)(m) + offsetof(struct m, v))
+#define	CPUMASK_PTR(v, m) 	cpumask_t *v = &(m->v)
 
 #define cpumask_scnprintf(buf, len, src) \
 			__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)