Introduce the cpumask_t type. The purpose of the type is to create a

level of abstraction for any and all CPU mask and CPU bitmap variables
so that platforms have the ability to break free from the hard limit
of 32 CPUs, simply because we don't have more bits in an u_int. Note
that the type is not supposed to solve massive parallelism, where
the number of CPUs can be larger than the width of the widest integral
type. As such, cpumask_t is not supposed to be a compound type. If
such would be necessary in the future, we can deal with the issues
then and there. For now, it can be assumed that the type is integral
and unsigned.

With this commit, all MD definitions start off as u_int. This allows
us to phase-in cpumask_t at our leasure without breaking anything.
Once cpumask_t is used consistently, platforms can switch to wider
(or smaller) types if such would be beneficial (or not; whatever :-)

Compile-tested on: i386

sys/alpha/include/_types.h

@@ -55,6 +55,7 @@ typedef	unsigned long		__uint64_t;
  * Standard type definitions.
  */
 typedef	__int32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int64_t	__critical_t;
 typedef	double		__double_t;
 typedef	float		__float_t;

sys/amd64/include/_types.h

@@ -55,6 +55,7 @@ typedef	unsigned long		__uint64_t;
  * Standard type definitions.
  */
 typedef	__int32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int64_t	__critical_t;
 typedef	double		__double_t;
 typedef	double		__float_t;

sys/arm/include/_types.h

@@ -63,6 +63,7 @@ typedef	unsigned long long	__uint64_t;
  * Standard type definitions.
  */
 typedef	__uint32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int32_t	__critical_t;
 typedef	__int32_t	__intfptr_t;
 typedef	__int64_t	__intmax_t;

sys/i386/include/_types.h

@@ -68,6 +68,7 @@ typedef	unsigned long long	__uint64_t;
  * Standard type definitions.
  */
 typedef	unsigned long	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int32_t	__critical_t;
 typedef	double		__double_t;
 typedef	double		__float_t;

sys/ia64/include/_types.h

@@ -55,6 +55,7 @@ typedef	unsigned long		__uint64_t;
  * Standard type definitions.
  */
 typedef	__int32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int64_t	__critical_t;
 typedef	double		__double_t;
 typedef	float		__float_t;

sys/powerpc/include/_types.h

@@ -68,6 +68,7 @@ typedef unsigned long long	__uint64_t;
  * Standard type definitions.
  */
 typedef	__uint32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int32_t	__critical_t;
 typedef	double		__double_t;
 typedef	double		__float_t;

sys/sparc64/include/_types.h

@@ -55,6 +55,7 @@ typedef	unsigned long		__uint64_t;
  * Standard type definitions.
  */
 typedef	__int32_t	__clock_t;		/* clock()... */
+typedef	unsigned int	__cpumask_t;
 typedef	__int64_t	__critical_t;
 typedef	double		__double_t;
 typedef	float		__float_t;

sys/sys/types.h

@@ -255,6 +255,7 @@ typedef	__vm_size_t	vm_size_t;
 
 #ifdef _KERNEL
 typedef	int		boolean_t;
+typedef	__cpumask_t	cpumask_t;
 typedef	__intfptr_t	intfptr_t;
 
 /*-