/*
* Cpumasks provide a bitmap suitable for representing the
- * set of CPU's in a system, one bit position per CPU number. In general,
+ * set of CPUs in a system, one bit position per CPU number. In general,
* only nr_cpu_ids (<= NR_CPUS) bits are valid.
*/
+#include <linux/cleanup.h>
#include <linux/kernel.h>
#include <linux/threads.h>
#include <linux/bitmap.h>
*/
#define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
-#if NR_CPUS == 1
-#define nr_cpu_ids 1U
+#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
+#define nr_cpu_ids ((unsigned int)NR_CPUS)
#else
extern unsigned int nr_cpu_ids;
#endif
-#ifdef CONFIG_CPUMASK_OFFSTACK
-/* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also,
- * not all bits may be allocated. */
-#define nr_cpumask_bits nr_cpu_ids
+static inline void set_nr_cpu_ids(unsigned int nr)
+{
+#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
+ WARN_ON(nr != nr_cpu_ids);
+#else
+ nr_cpu_ids = nr;
+#endif
+}
+
+/*
+ * We have several different "preferred sizes" for the cpumask
+ * operations, depending on operation.
+ *
+ * For example, the bitmap scanning and operating operations have
+ * optimized routines that work for the single-word case, but only when
+ * the size is constant. So if NR_CPUS fits in one single word, we are
+ * better off using that small constant, in order to trigger the
+ * optimized bit finding. That is 'small_cpumask_size'.
+ *
+ * The clearing and copying operations will similarly perform better
+ * with a constant size, but we limit that size arbitrarily to four
+ * words. We call this 'large_cpumask_size'.
+ *
+ * Finally, some operations just want the exact limit, either because
+ * they set bits or just don't have any faster fixed-sized versions. We
+ * call this just 'nr_cpumask_bits'.
+ *
+ * Note that these optional constants are always guaranteed to be at
+ * least as big as 'nr_cpu_ids' itself is, and all our cpumask
+ * allocations are at least that size (see cpumask_size()). The
+ * optimization comes from being able to potentially use a compile-time
+ * constant instead of a run-time generated exact number of CPUs.
+ */
+#if NR_CPUS <= BITS_PER_LONG
+ #define small_cpumask_bits ((unsigned int)NR_CPUS)
+ #define large_cpumask_bits ((unsigned int)NR_CPUS)
+#elif NR_CPUS <= 4*BITS_PER_LONG
+ #define small_cpumask_bits nr_cpu_ids
+ #define large_cpumask_bits ((unsigned int)NR_CPUS)
#else
-#define nr_cpumask_bits ((unsigned int)NR_CPUS)
+ #define small_cpumask_bits nr_cpu_ids
+ #define large_cpumask_bits nr_cpu_ids
#endif
+#define nr_cpumask_bits nr_cpu_ids
/*
* The following particular system cpumasks and operations manage
*
* If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
*
- * The cpu_possible_mask is fixed at boot time, as the set of CPU id's
+ * The cpu_possible_mask is fixed at boot time, as the set of CPU IDs
* that it is possible might ever be plugged in at anytime during the
* life of that system boot. The cpu_present_mask is dynamic(*),
* representing which CPUs are currently plugged in. And
* cpu_online_mask is the dynamic subset of cpu_present_mask,
* indicating those CPUs available for scheduling.
*
- * If HOTPLUG is enabled, then cpu_possible_mask is forced to have
- * all NR_CPUS bits set, otherwise it is just the set of CPUs that
- * ACPI reports present at boot.
- *
* If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
* depending on what ACPI reports as currently plugged in, otherwise
* cpu_present_mask is just a copy of cpu_possible_mask.
* hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
*
* Subtleties:
- * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
+ * 1) UP ARCHes (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
* assumption that their single CPU is online. The UP
* cpu_{online,possible,present}_masks are placebos. Changing them
* will have no useful affect on the following num_*_cpus()
/* verify cpu argument to cpumask_* operators */
static __always_inline unsigned int cpumask_check(unsigned int cpu)
{
- cpu_max_bits_warn(cpu, nr_cpumask_bits);
+ cpu_max_bits_warn(cpu, small_cpumask_bits);
return cpu;
}
-#if NR_CPUS == 1
-/* Uniprocessor. Assume all masks are "1". */
-static inline unsigned int cpumask_first(const struct cpumask *srcp)
-{
- return 0;
-}
-
-static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
-{
- return 0;
-}
-
-static inline unsigned int cpumask_first_and(const struct cpumask *srcp1,
- const struct cpumask *srcp2)
-{
- return 0;
-}
-
-static inline unsigned int cpumask_last(const struct cpumask *srcp)
-{
- return 0;
-}
-
-/* Valid inputs for n are -1 and 0. */
-static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
-{
- return n+1;
-}
-
-static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
-{
- return n+1;
-}
-
-static inline unsigned int cpumask_next_and(int n,
- const struct cpumask *srcp,
- const struct cpumask *andp)
-{
- return n+1;
-}
-
-static inline unsigned int cpumask_next_wrap(int n, const struct cpumask *mask,
- int start, bool wrap)
-{
- /* cpu0 unless stop condition, wrap and at cpu0, then nr_cpumask_bits */
- return (wrap && n == 0);
-}
-
-/* cpu must be a valid cpu, ie 0, so there's no other choice. */
-static inline unsigned int cpumask_any_but(const struct cpumask *mask,
- unsigned int cpu)
-{
- return 1;
-}
-
-static inline unsigned int cpumask_local_spread(unsigned int i, int node)
-{
- return 0;
-}
-
-static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
- const struct cpumask *src2p) {
- return cpumask_first_and(src1p, src2p);
-}
-
-static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
-{
- return cpumask_first(srcp);
-}
-
-#define for_each_cpu(cpu, mask) \
- for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
-#define for_each_cpu_not(cpu, mask) \
- for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
-#define for_each_cpu_wrap(cpu, mask, start) \
- for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start))
-#define for_each_cpu_and(cpu, mask1, mask2) \
- for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2)
-#else
/**
* cpumask_first - get the first cpu in a cpumask
* @srcp: the cpumask pointer
*
- * Returns >= nr_cpu_ids if no cpus set.
+ * Return: >= nr_cpu_ids if no cpus set.
*/
static inline unsigned int cpumask_first(const struct cpumask *srcp)
{
- return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
+ return find_first_bit(cpumask_bits(srcp), small_cpumask_bits);
}
/**
* cpumask_first_zero - get the first unset cpu in a cpumask
* @srcp: the cpumask pointer
*
- * Returns >= nr_cpu_ids if all cpus are set.
+ * Return: >= nr_cpu_ids if all cpus are set.
*/
static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
{
- return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits);
+ return find_first_zero_bit(cpumask_bits(srcp), small_cpumask_bits);
}
/**
* cpumask_first_and - return the first cpu from *srcp1 & *srcp2
- * @src1p: the first input
- * @src2p: the second input
+ * @srcp1: the first input
+ * @srcp2: the second input
*
- * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
+ * Return: >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
*/
static inline
unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
{
- return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits);
+ return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
}
/**
* cpumask_last - get the last CPU in a cpumask
* @srcp: - the cpumask pointer
*
- * Returns >= nr_cpumask_bits if no CPUs set.
+ * Return: >= nr_cpumask_bits if no CPUs set.
*/
static inline unsigned int cpumask_last(const struct cpumask *srcp)
{
- return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
+ return find_last_bit(cpumask_bits(srcp), small_cpumask_bits);
}
/**
* cpumask_next - get the next cpu in a cpumask
- * @n: the cpu prior to the place to search (ie. return will be > @n)
+ * @n: the cpu prior to the place to search (i.e. return will be > @n)
* @srcp: the cpumask pointer
*
- * Returns >= nr_cpu_ids if no further cpus set.
+ * Return: >= nr_cpu_ids if no further cpus set.
*/
static inline
unsigned int cpumask_next(int n, const struct cpumask *srcp)
/* -1 is a legal arg here. */
if (n != -1)
cpumask_check(n);
- return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
+ return find_next_bit(cpumask_bits(srcp), small_cpumask_bits, n + 1);
}
/**
* cpumask_next_zero - get the next unset cpu in a cpumask
- * @n: the cpu prior to the place to search (ie. return will be > @n)
+ * @n: the cpu prior to the place to search (i.e. return will be > @n)
* @srcp: the cpumask pointer
*
- * Returns >= nr_cpu_ids if no further cpus unset.
+ * Return: >= nr_cpu_ids if no further cpus unset.
*/
static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
{
/* -1 is a legal arg here. */
if (n != -1)
cpumask_check(n);
- return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
+ return find_next_zero_bit(cpumask_bits(srcp), small_cpumask_bits, n+1);
+}
+
+#if NR_CPUS == 1
+/* Uniprocessor: there is only one valid CPU */
+static inline unsigned int cpumask_local_spread(unsigned int i, int node)
+{
+ return 0;
+}
+
+static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ return cpumask_first_and(src1p, src2p);
}
+static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
+{
+ return cpumask_first(srcp);
+}
+#else
+unsigned int cpumask_local_spread(unsigned int i, int node);
+unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
+ const struct cpumask *src2p);
+unsigned int cpumask_any_distribute(const struct cpumask *srcp);
+#endif /* NR_CPUS */
+
/**
* cpumask_next_and - get the next cpu in *src1p & *src2p
- * @n: the cpu prior to the place to search (ie. return will be > @n)
+ * @n: the cpu prior to the place to search (i.e. return will be > @n)
* @src1p: the first cpumask pointer
* @src2p: the second cpumask pointer
*
- * Returns >= nr_cpu_ids if no further cpus set in both.
+ * Return: >= nr_cpu_ids if no further cpus set in both.
*/
static inline
unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
if (n != -1)
cpumask_check(n);
return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
- nr_cpumask_bits, n + 1);
+ small_cpumask_bits, n + 1);
}
-unsigned int cpumask_local_spread(unsigned int i, int node);
-unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
- const struct cpumask *src2p);
-unsigned int cpumask_any_distribute(const struct cpumask *srcp);
-
/**
* for_each_cpu - iterate over every cpu in a mask
* @cpu: the (optionally unsigned) integer iterator
* After the loop, cpu is >= nr_cpu_ids.
*/
#define for_each_cpu(cpu, mask) \
- for ((cpu) = -1; \
- (cpu) = cpumask_next((cpu), (mask)), \
- (cpu) < nr_cpu_ids;)
+ for_each_set_bit(cpu, cpumask_bits(mask), small_cpumask_bits)
-/**
- * for_each_cpu_not - iterate over every cpu in a complemented mask
- * @cpu: the (optionally unsigned) integer iterator
- * @mask: the cpumask pointer
- *
- * After the loop, cpu is >= nr_cpu_ids.
- */
-#define for_each_cpu_not(cpu, mask) \
- for ((cpu) = -1; \
- (cpu) = cpumask_next_zero((cpu), (mask)), \
- (cpu) < nr_cpu_ids;)
+#if NR_CPUS == 1
+static inline
+unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
+{
+ cpumask_check(start);
+ if (n != -1)
+ cpumask_check(n);
-unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
+ /*
+ * Return the first available CPU when wrapping, or when starting before cpu0,
+ * since there is only one valid option.
+ */
+ if (wrap && n >= 0)
+ return nr_cpumask_bits;
+
+ return cpumask_first(mask);
+}
+#else
+unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
+#endif
/**
* for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
*
* After the loop, cpu is >= nr_cpu_ids.
*/
-#define for_each_cpu_wrap(cpu, mask, start) \
- for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \
- (cpu) < nr_cpumask_bits; \
- (cpu) = cpumask_next_wrap((cpu), (mask), (start), true))
+#define for_each_cpu_wrap(cpu, mask, start) \
+ for_each_set_bit_wrap(cpu, cpumask_bits(mask), small_cpumask_bits, start)
/**
* for_each_cpu_and - iterate over every cpu in both masks
* After the loop, cpu is >= nr_cpu_ids.
*/
#define for_each_cpu_and(cpu, mask1, mask2) \
- for ((cpu) = -1; \
- (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \
- (cpu) < nr_cpu_ids;)
+ for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
+
+/**
+ * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding
+ * those present in another.
+ * @cpu: the (optionally unsigned) integer iterator
+ * @mask1: the first cpumask pointer
+ * @mask2: the second cpumask pointer
+ *
+ * This saves a temporary CPU mask in many places. It is equivalent to:
+ * struct cpumask tmp;
+ * cpumask_andnot(&tmp, &mask1, &mask2);
+ * for_each_cpu(cpu, &tmp)
+ * ...
+ *
+ * After the loop, cpu is >= nr_cpu_ids.
+ */
+#define for_each_cpu_andnot(cpu, mask1, mask2) \
+ for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
+
+/**
+ * for_each_cpu_or - iterate over every cpu present in either mask
+ * @cpu: the (optionally unsigned) integer iterator
+ * @mask1: the first cpumask pointer
+ * @mask2: the second cpumask pointer
+ *
+ * This saves a temporary CPU mask in many places. It is equivalent to:
+ * struct cpumask tmp;
+ * cpumask_or(&tmp, &mask1, &mask2);
+ * for_each_cpu(cpu, &tmp)
+ * ...
+ *
+ * After the loop, cpu is >= nr_cpu_ids.
+ */
+#define for_each_cpu_or(cpu, mask1, mask2) \
+ for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
/**
* cpumask_any_but - return a "random" in a cpumask, but not this one.
* @cpu: the cpu to ignore.
*
* Often used to find any cpu but smp_processor_id() in a mask.
- * Returns >= nr_cpu_ids if no cpus set.
+ * Return: >= nr_cpu_ids if no cpus set.
*/
static inline
unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
break;
return i;
}
-#endif /* SMP */
+
+/**
+ * cpumask_nth - get the Nth cpu in a cpumask
+ * @srcp: the cpumask pointer
+ * @cpu: the Nth cpu to find, starting from 0
+ *
+ * Return: >= nr_cpu_ids if such cpu doesn't exist.
+ */
+static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
+{
+ return find_nth_bit(cpumask_bits(srcp), small_cpumask_bits, cpumask_check(cpu));
+}
+
+/**
+ * cpumask_nth_and - get the Nth cpu in 2 cpumasks
+ * @srcp1: the cpumask pointer
+ * @srcp2: the cpumask pointer
+ * @cpu: the Nth cpu to find, starting from 0
+ *
+ * Return: >= nr_cpu_ids if such cpu doesn't exist.
+ */
+static inline
+unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
+ const struct cpumask *srcp2)
+{
+ return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
+ small_cpumask_bits, cpumask_check(cpu));
+}
+
+/**
+ * cpumask_nth_andnot - get the Nth cpu set in 1st cpumask, and clear in 2nd.
+ * @srcp1: the cpumask pointer
+ * @srcp2: the cpumask pointer
+ * @cpu: the Nth cpu to find, starting from 0
+ *
+ * Return: >= nr_cpu_ids if such cpu doesn't exist.
+ */
+static inline
+unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
+ const struct cpumask *srcp2)
+{
+ return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
+ small_cpumask_bits, cpumask_check(cpu));
+}
+
+/**
+ * cpumask_nth_and_andnot - get the Nth cpu set in 1st and 2nd cpumask, and clear in 3rd.
+ * @srcp1: the cpumask pointer
+ * @srcp2: the cpumask pointer
+ * @srcp3: the cpumask pointer
+ * @cpu: the Nth cpu to find, starting from 0
+ *
+ * Return: >= nr_cpu_ids if such cpu doesn't exist.
+ */
+static __always_inline
+unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
+ const struct cpumask *srcp2,
+ const struct cpumask *srcp3)
+{
+ return find_nth_and_andnot_bit(cpumask_bits(srcp1),
+ cpumask_bits(srcp2),
+ cpumask_bits(srcp3),
+ small_cpumask_bits, cpumask_check(cpu));
+}
#define CPU_BITS_NONE \
{ \
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
- * Returns true if @cpu is set in @cpumask, else returns false
+ * Return: true if @cpu is set in @cpumask, else returns false
*/
static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
{
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
- * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
- *
* test_and_set_bit wrapper for cpumasks.
+ *
+ * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
*/
static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
{
* @cpu: cpu number (< nr_cpu_ids)
* @cpumask: the cpumask pointer
*
- * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
- *
* test_and_clear_bit wrapper for cpumasks.
+ *
+ * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
*/
static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
{
*/
static inline void cpumask_setall(struct cpumask *dstp)
{
+ if (small_const_nbits(small_cpumask_bits)) {
+ cpumask_bits(dstp)[0] = BITMAP_LAST_WORD_MASK(nr_cpumask_bits);
+ return;
+ }
bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
}
*/
static inline void cpumask_clear(struct cpumask *dstp)
{
- bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
+ bitmap_zero(cpumask_bits(dstp), large_cpumask_bits);
}
/**
* @src1p: the first input
* @src2p: the second input
*
- * If *@dstp is empty, returns false, else returns true
+ * Return: false if *@dstp is empty, else returns true
*/
static inline bool cpumask_and(struct cpumask *dstp,
const struct cpumask *src1p,
const struct cpumask *src2p)
{
return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
- cpumask_bits(src2p), nr_cpumask_bits);
+ cpumask_bits(src2p), small_cpumask_bits);
}
/**
const struct cpumask *src2p)
{
bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
- cpumask_bits(src2p), nr_cpumask_bits);
+ cpumask_bits(src2p), small_cpumask_bits);
}
/**
const struct cpumask *src2p)
{
bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
- cpumask_bits(src2p), nr_cpumask_bits);
+ cpumask_bits(src2p), small_cpumask_bits);
}
/**
* @src1p: the first input
* @src2p: the second input
*
- * If *@dstp is empty, returns false, else returns true
+ * Return: false if *@dstp is empty, else returns true
*/
static inline bool cpumask_andnot(struct cpumask *dstp,
const struct cpumask *src1p,
const struct cpumask *src2p)
{
return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
- cpumask_bits(src2p), nr_cpumask_bits);
-}
-
-/**
- * cpumask_complement - *dstp = ~*srcp
- * @dstp: the cpumask result
- * @srcp: the input to invert
- */
-static inline void cpumask_complement(struct cpumask *dstp,
- const struct cpumask *srcp)
-{
- bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
- nr_cpumask_bits);
+ cpumask_bits(src2p), small_cpumask_bits);
}
/**
* cpumask_equal - *src1p == *src2p
* @src1p: the first input
* @src2p: the second input
+ *
+ * Return: true if the cpumasks are equal, false if not
*/
static inline bool cpumask_equal(const struct cpumask *src1p,
const struct cpumask *src2p)
{
return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
- nr_cpumask_bits);
+ small_cpumask_bits);
}
/**
* @src1p: the first input
* @src2p: the second input
* @src3p: the third input
+ *
+ * Return: true if first cpumask ORed with second cpumask == third cpumask,
+ * otherwise false
*/
static inline bool cpumask_or_equal(const struct cpumask *src1p,
const struct cpumask *src2p,
const struct cpumask *src3p)
{
return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
- cpumask_bits(src3p), nr_cpumask_bits);
+ cpumask_bits(src3p), small_cpumask_bits);
}
/**
* cpumask_intersects - (*src1p & *src2p) != 0
* @src1p: the first input
* @src2p: the second input
+ *
+ * Return: true if first cpumask ANDed with second cpumask is non-empty,
+ * otherwise false
*/
static inline bool cpumask_intersects(const struct cpumask *src1p,
const struct cpumask *src2p)
{
return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
- nr_cpumask_bits);
+ small_cpumask_bits);
}
/**
* @src1p: the first input
* @src2p: the second input
*
- * Returns true if *@src1p is a subset of *@src2p, else returns false
+ * Return: true if *@src1p is a subset of *@src2p, else returns false
*/
static inline bool cpumask_subset(const struct cpumask *src1p,
const struct cpumask *src2p)
{
return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
- nr_cpumask_bits);
+ small_cpumask_bits);
}
/**
* cpumask_empty - *srcp == 0
* @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
+ *
+ * Return: true if srcp is empty (has no bits set), else false
*/
static inline bool cpumask_empty(const struct cpumask *srcp)
{
- return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
+ return bitmap_empty(cpumask_bits(srcp), small_cpumask_bits);
}
/**
* cpumask_full - *srcp == 0xFFFFFFFF...
* @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
+ *
+ * Return: true if srcp is full (has all bits set), else false
*/
static inline bool cpumask_full(const struct cpumask *srcp)
{
/**
* cpumask_weight - Count of bits in *srcp
* @srcp: the cpumask to count bits (< nr_cpu_ids) in.
+ *
+ * Return: count of bits set in *srcp
*/
static inline unsigned int cpumask_weight(const struct cpumask *srcp)
{
- return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
+ return bitmap_weight(cpumask_bits(srcp), small_cpumask_bits);
+}
+
+/**
+ * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
+ * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
+ * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
+ *
+ * Return: count of bits set in both *srcp1 and *srcp2
+ */
+static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1,
+ const struct cpumask *srcp2)
+{
+ return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
+}
+
+/**
+ * cpumask_weight_andnot - Count of bits in (*srcp1 & ~*srcp2)
+ * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
+ * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
+ *
+ * Return: count of bits set in both *srcp1 and *srcp2
+ */
+static inline unsigned int cpumask_weight_andnot(const struct cpumask *srcp1,
+ const struct cpumask *srcp2)
+{
+ return bitmap_weight_andnot(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
}
/**
const struct cpumask *srcp, int n)
{
bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
- nr_cpumask_bits);
+ small_cpumask_bits);
}
/**
static inline void cpumask_copy(struct cpumask *dstp,
const struct cpumask *srcp)
{
- bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
+ bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), large_cpumask_bits);
}
/**
* cpumask_any - pick a "random" cpu from *srcp
* @srcp: the input cpumask
*
- * Returns >= nr_cpu_ids if no cpus set.
+ * Return: >= nr_cpu_ids if no cpus set.
*/
#define cpumask_any(srcp) cpumask_first(srcp)
* @mask1: the first input cpumask
* @mask2: the second input cpumask
*
- * Returns >= nr_cpu_ids if no cpus set.
+ * Return: >= nr_cpu_ids if no cpus set.
*/
#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
* @len: the length of the buffer
* @dstp: the cpumask to set.
*
- * Returns -errno, or 0 for success.
+ * Return: -errno, or 0 for success.
*/
static inline int cpumask_parse_user(const char __user *buf, int len,
struct cpumask *dstp)
* @len: the length of the buffer
* @dstp: the cpumask to set.
*
- * Returns -errno, or 0 for success.
+ * Return: -errno, or 0 for success.
*/
static inline int cpumask_parselist_user(const char __user *buf, int len,
struct cpumask *dstp)
* @buf: the buffer to extract from
* @dstp: the cpumask to set.
*
- * Returns -errno, or 0 for success.
+ * Return: -errno, or 0 for success.
*/
static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
{
* @buf: the buffer to extract from
* @dstp: the cpumask to set.
*
- * Returns -errno, or 0 for success.
+ * Return: -errno, or 0 for success.
*/
static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
{
}
/**
- * cpumask_size - size to allocate for a 'struct cpumask' in bytes
+ * cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
+ *
+ * Return: size to allocate for a &struct cpumask in bytes
*/
static inline unsigned int cpumask_size(void)
{
- return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
+ return BITS_TO_LONGS(large_cpumask_bits) * sizeof(long);
}
/*
* little more difficult, we typedef cpumask_var_t to an array or a
* pointer: doing &mask on an array is a noop, so it still works.
*
- * ie.
+ * i.e.
* cpumask_var_t tmpmask;
* if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
* return -ENOMEM;
* a nop returning a constant 1 (in <linux/cpumask.h>).
*
* See alloc_cpumask_var_node.
+ *
+ * Return: %true if allocation succeeded, %false if not
*/
static inline
bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
}
#endif /* CONFIG_CPUMASK_OFFSTACK */
+DEFINE_FREE(free_cpumask_var, struct cpumask *, if (_T) free_cpumask_var(_T));
+
/* It's common to want to use cpu_all_mask in struct member initializers,
* so it has to refer to an address rather than a pointer. */
extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
/* First bits of cpu_bit_bitmap are in fact unset. */
#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
+#if NR_CPUS == 1
+/* Uniprocessor: the possible/online/present masks are always "1" */
+#define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
+#define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
+#define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
+#else
#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
#define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
#define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
+#endif
/* Wrappers for arch boot code to manipulate normally-constant masks */
void init_cpu_present(const struct cpumask *src);
}
/**
- * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
+ * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
* @bitmap: the bitmap
*
* There are a few places where cpumask_var_t isn't appropriate and
* interface gives only a momentary snapshot and is not protected against
* concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
* region.
+ *
+ * Return: momentary snapshot of the number of online CPUs
*/
-static inline unsigned int num_online_cpus(void)
+static __always_inline unsigned int num_online_cpus(void)
{
- return atomic_read(&__num_online_cpus);
+ return raw_atomic_read(&__num_online_cpus);
}
#define num_possible_cpus() cpumask_weight(cpu_possible_mask)
#define num_present_cpus() cpumask_weight(cpu_present_mask)
* @mask: the cpumask to copy
* @buf: the buffer to copy into
*
- * Returns the length of the (null-terminated) @buf string, zero if
+ * Return: the length of the (null-terminated) @buf string, zero if
* nothing is copied.
*/
static inline ssize_t
* cpumask; Typically used by bin_attribute to export cpumask bitmask
* ABI.
*
- * Returns the length of how many bytes have been copied, excluding
+ * Return: the length of how many bytes have been copied, excluding
* terminating '\0'.
*/
static inline ssize_t
/**
* cpumap_print_list_to_buf - copies the cpumask into the buffer as
* comma-separated list of cpus
+ * @buf: the buffer to copy into
+ * @mask: the cpumask to copy
+ * @off: in the string from which we are copying, we copy to @buf
+ * @count: the maximum number of bytes to print
*
* Everything is same with the above cpumap_print_bitmask_to_buf()
* except the print format.
+ *
+ * Return: the length of how many bytes have been copied, excluding
+ * terminating '\0'.
*/
static inline ssize_t
cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
[0] = 1UL \
} }
+/*
+ * Provide a valid theoretical max size for cpumap and cpulist sysfs files
+ * to avoid breaking userspace which may allocate a buffer based on the size
+ * reported by e.g. fstat.
+ *
+ * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
+ *
+ * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
+ * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
+ * cover a worst-case of every other cpu being on one of two nodes for a
+ * very large NR_CPUS.
+ *
+ * Use PAGE_SIZE as a minimum for smaller configurations while avoiding
+ * unsigned comparison to -1.
+ */
+#define CPUMAP_FILE_MAX_BYTES (((NR_CPUS * 9)/32 > PAGE_SIZE) \
+ ? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
+#define CPULIST_FILE_MAX_BYTES (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)
+
#endif /* __LINUX_CPUMASK_H */
projects / linux-2.6-microblaze.git / blobdiff