Commit 80422d34 authored by Mike Travis's avatar Mike Travis Committed by Ingo Molnar
Browse files

cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP 



  * Rename CPUMASK_VAR --> CPUMASK_PTR (and simplify)

  * Fix a semantic error in CPUMASK_ALLOC

  * Add a bit of commentry to cpumask.h

Signed-off-by: default avatarMike Travis <travis@sgi.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b38868aa

include/linux/cpumask.h

+26 −7
Original line number Diff line number Diff line
@@ -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)