* int next_cpu_nr(cpu, mask) Next cpu past 'cpu', or nr_cpu_ids
*
* cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set
+ * (can be used as an lvalue)
* CPU_MASK_ALL Initializer - all bits set
* 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 =
+ * 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_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
* int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing
bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
}
+/*
+ * Special-case data structure for "single bit set only" constant CPU masks.
+ *
+ * We pre-generate all the 64 (or 32) possible bit positions, with enough
+ * padding to the left and the right, and return the constant pointer
+ * appropriately offset.
+ */
+extern const unsigned long
+ cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
-#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
-extern cpumask_t *cpumask_of_cpu_map;
-#define cpumask_of_cpu(cpu) (cpumask_of_cpu_map[cpu])
+static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
+{
+ const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
+ p -= cpu / BITS_PER_LONG;
+ return (const cpumask_t *)p;
+}
+
+/*
+ * In cases where we take the address of the cpumask immediately,
+ * gcc optimizes it out (it's a constant) and there's no huge stack
+ * variable created:
+ */
+#define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
-#else
-#define cpumask_of_cpu(cpu) \
-(*({ \
- typeof(_unused_cpumask_arg_) m; \
- if (sizeof(m) == sizeof(unsigned long)) { \
- m.bits[0] = 1UL<<(cpu); \
- } else { \
- cpus_clear(m); \
- cpu_set((cpu), m); \
- } \
- &m; \
-}))
-#endif
#define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
#define cpus_addr(src) ((src).bits)
+#if NR_CPUS > BITS_PER_LONG
+#define CPUMASK_ALLOC(m) struct m *m = kmalloc(sizeof(*m), GFP_KERNEL)
+#define CPUMASK_FREE(m) kfree(m)
+#else
+#define CPUMASK_ALLOC(m) struct m _m, *m = &_m
+#define CPUMASK_FREE(m)
+#endif
+#define CPUMASK_PTR(v, m) cpumask_t *v = &(m->v)
+
#define cpumask_scnprintf(buf, len, src) \
__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
static inline int __cpumask_scnprintf(char *buf, int len,
#endif /* NR_CPUS > 64 */
-#define next_cpu_nr(n, src) next_cpu(n, src)
-#define cpus_weight_nr(cpumask) cpus_weight(cpumask)
-#define for_each_cpu_mask_nr(cpu, mask) for_each_cpu_mask(cpu, mask)
-
/*
* The following particular system cpumasks and operations manage
- * possible, present and online cpus. Each of them is a fixed size
+ * possible, present, active and online cpus. Each of them is a fixed size
* bitmap of size NR_CPUS.
*
* #ifdef CONFIG_HOTPLUG_CPU
* cpu_possible_map - has bit 'cpu' set iff cpu is populatable
* cpu_present_map - has bit 'cpu' set iff cpu is populated
* cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
+ * cpu_active_map - has bit 'cpu' set iff cpu available to migration
* #else
* cpu_possible_map - has bit 'cpu' set iff cpu is populated
* cpu_present_map - copy of cpu_possible_map
extern cpumask_t cpu_possible_map;
extern cpumask_t cpu_online_map;
extern cpumask_t cpu_present_map;
+extern cpumask_t cpu_active_map;
#if NR_CPUS > 1
#define num_online_cpus() cpus_weight_nr(cpu_online_map)
#define cpu_online(cpu) cpu_isset((cpu), cpu_online_map)
#define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map)
#define cpu_present(cpu) cpu_isset((cpu), cpu_present_map)
+#define cpu_active(cpu) cpu_isset((cpu), cpu_active_map)
#else
#define num_online_cpus() 1
#define num_possible_cpus() 1
#define cpu_online(cpu) ((cpu) == 0)
#define cpu_possible(cpu) ((cpu) == 0)
#define cpu_present(cpu) ((cpu) == 0)
+#define cpu_active(cpu) ((cpu) == 0)
#endif
#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))