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-rw-r--r--kernel/include/linux/cpumask.h820
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diff --git a/kernel/include/linux/cpumask.h b/kernel/include/linux/cpumask.h
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+++ b/kernel/include/linux/cpumask.h
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+#ifndef __LINUX_CPUMASK_H
+#define __LINUX_CPUMASK_H
+
+/*
+ * Cpumasks provide a bitmap suitable for representing the
+ * set of CPU's in a system, one bit position per CPU number. In general,
+ * only nr_cpu_ids (<= NR_CPUS) bits are valid.
+ */
+#include <linux/kernel.h>
+#include <linux/threads.h>
+#include <linux/bitmap.h>
+#include <linux/bug.h>
+
+/* Don't assign or return these: may not be this big! */
+typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
+
+/**
+ * cpumask_bits - get the bits in a cpumask
+ * @maskp: the struct cpumask *
+ *
+ * You should only assume nr_cpu_ids bits of this mask are valid. This is
+ * a macro so it's const-correct.
+ */
+#define cpumask_bits(maskp) ((maskp)->bits)
+
+/**
+ * cpumask_pr_args - printf args to output a cpumask
+ * @maskp: cpumask to be printed
+ *
+ * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
+ */
+#define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
+
+#if NR_CPUS == 1
+#define nr_cpu_ids 1
+#else
+extern 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
+#else
+#define nr_cpumask_bits NR_CPUS
+#endif
+
+/*
+ * The following particular system cpumasks and operations manage
+ * possible, present, active and online cpus.
+ *
+ * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
+ * cpu_present_mask - has bit 'cpu' set iff cpu is populated
+ * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
+ * cpu_active_mask - has bit 'cpu' set iff cpu available to migration
+ *
+ * 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
+ * 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.
+ *
+ * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not
+ * 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
+ * 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()
+ * and cpu_*() macros in the UP case. This ugliness is a UP
+ * optimization - don't waste any instructions or memory references
+ * asking if you're online or how many CPUs there are if there is
+ * only one CPU.
+ */
+
+extern const struct cpumask *const cpu_possible_mask;
+extern const struct cpumask *const cpu_online_mask;
+extern const struct cpumask *const cpu_present_mask;
+extern const struct cpumask *const cpu_active_mask;
+
+#if NR_CPUS > 1
+#define num_online_cpus() cpumask_weight(cpu_online_mask)
+#define num_possible_cpus() cpumask_weight(cpu_possible_mask)
+#define num_present_cpus() cpumask_weight(cpu_present_mask)
+#define num_active_cpus() cpumask_weight(cpu_active_mask)
+#define cpu_online(cpu) cpumask_test_cpu((cpu), cpu_online_mask)
+#define cpu_possible(cpu) cpumask_test_cpu((cpu), cpu_possible_mask)
+#define cpu_present(cpu) cpumask_test_cpu((cpu), cpu_present_mask)
+#define cpu_active(cpu) cpumask_test_cpu((cpu), cpu_active_mask)
+#else
+#define num_online_cpus() 1U
+#define num_possible_cpus() 1U
+#define num_present_cpus() 1U
+#define num_active_cpus() 1U
+#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
+
+/* verify cpu argument to cpumask_* operators */
+static inline unsigned int cpumask_check(unsigned int cpu)
+{
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+ WARN_ON_ONCE(cpu >= nr_cpumask_bits);
+#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
+ return cpu;
+}
+
+#if NR_CPUS == 1
+/* Uniprocessor. Assume all masks are "1". */
+static inline unsigned int cpumask_first(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;
+}
+
+/* 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;
+}
+
+#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_and(cpu, mask, and) \
+ for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and)
+#else
+/**
+ * cpumask_first - get the first cpu in a cpumask
+ * @srcp: the cpumask pointer
+ *
+ * Returns >= 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);
+}
+
+/**
+ * cpumask_next - get the next cpu in a cpumask
+ * @n: the cpu prior to the place to search (ie. return will be > @n)
+ * @srcp: the cpumask pointer
+ *
+ * Returns >= 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);
+}
+
+/**
+ * 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)
+ * @srcp: the cpumask pointer
+ *
+ * Returns >= 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);
+}
+
+int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
+int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
+unsigned int cpumask_local_spread(unsigned int i, int node);
+
+/**
+ * for_each_cpu - iterate over every cpu in a mask
+ * @cpu: the (optionally unsigned) integer iterator
+ * @mask: the cpumask pointer
+ *
+ * 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_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;)
+
+/**
+ * for_each_cpu_and - iterate over every cpu in both masks
+ * @cpu: the (optionally unsigned) integer iterator
+ * @mask: the first cpumask pointer
+ * @and: the second cpumask pointer
+ *
+ * This saves a temporary CPU mask in many places. It is equivalent to:
+ * struct cpumask tmp;
+ * cpumask_and(&tmp, &mask, &and);
+ * for_each_cpu(cpu, &tmp)
+ * ...
+ *
+ * After the loop, cpu is >= nr_cpu_ids.
+ */
+#define for_each_cpu_and(cpu, mask, and) \
+ for ((cpu) = -1; \
+ (cpu) = cpumask_next_and((cpu), (mask), (and)), \
+ (cpu) < nr_cpu_ids;)
+#endif /* SMP */
+
+#define CPU_BITS_NONE \
+{ \
+ [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
+}
+
+#define CPU_BITS_CPU0 \
+{ \
+ [0] = 1UL \
+}
+
+/**
+ * cpumask_set_cpu - set a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @dstp: the cpumask pointer
+ */
+static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
+{
+ set_bit(cpumask_check(cpu), cpumask_bits(dstp));
+}
+
+/**
+ * cpumask_clear_cpu - clear a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @dstp: the cpumask pointer
+ */
+static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
+{
+ clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
+}
+
+/**
+ * cpumask_test_cpu - test for a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @cpumask: the cpumask pointer
+ *
+ * Returns 1 if @cpu is set in @cpumask, else returns 0
+ */
+static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
+{
+ return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
+}
+
+/**
+ * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @cpumask: the cpumask pointer
+ *
+ * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
+ *
+ * test_and_set_bit wrapper for cpumasks.
+ */
+static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
+{
+ return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
+}
+
+/**
+ * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @cpumask: the cpumask pointer
+ *
+ * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
+ *
+ * test_and_clear_bit wrapper for cpumasks.
+ */
+static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
+{
+ return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
+}
+
+/**
+ * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
+ * @dstp: the cpumask pointer
+ */
+static inline void cpumask_setall(struct cpumask *dstp)
+{
+ bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
+ * @dstp: the cpumask pointer
+ */
+static inline void cpumask_clear(struct cpumask *dstp)
+{
+ bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_and - *dstp = *src1p & *src2p
+ * @dstp: the cpumask result
+ * @src1p: the first input
+ * @src2p: the second input
+ *
+ * If *@dstp is empty, returns 0, else returns 1
+ */
+static inline int 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_or - *dstp = *src1p | *src2p
+ * @dstp: the cpumask result
+ * @src1p: the first input
+ * @src2p: the second input
+ */
+static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
+ cpumask_bits(src2p), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_xor - *dstp = *src1p ^ *src2p
+ * @dstp: the cpumask result
+ * @src1p: the first input
+ * @src2p: the second input
+ */
+static inline void cpumask_xor(struct cpumask *dstp,
+ const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
+ cpumask_bits(src2p), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_andnot - *dstp = *src1p & ~*src2p
+ * @dstp: the cpumask result
+ * @src1p: the first input
+ * @src2p: the second input
+ *
+ * If *@dstp is empty, returns 0, else returns 1
+ */
+static inline int 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_equal - *src1p == *src2p
+ * @src1p: the first input
+ * @src2p: the second input
+ */
+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);
+}
+
+/**
+ * cpumask_intersects - (*src1p & *src2p) != 0
+ * @src1p: the first input
+ * @src2p: the second input
+ */
+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);
+}
+
+/**
+ * cpumask_subset - (*src1p & ~*src2p) == 0
+ * @src1p: the first input
+ * @src2p: the second input
+ *
+ * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
+ */
+static inline int cpumask_subset(const struct cpumask *src1p,
+ const struct cpumask *src2p)
+{
+ return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
+ nr_cpumask_bits);
+}
+
+/**
+ * cpumask_empty - *srcp == 0
+ * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
+ */
+static inline bool cpumask_empty(const struct cpumask *srcp)
+{
+ return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_full - *srcp == 0xFFFFFFFF...
+ * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
+ */
+static inline bool cpumask_full(const struct cpumask *srcp)
+{
+ return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_weight - Count of bits in *srcp
+ * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
+ */
+static inline unsigned int cpumask_weight(const struct cpumask *srcp)
+{
+ return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_shift_right - *dstp = *srcp >> n
+ * @dstp: the cpumask result
+ * @srcp: the input to shift
+ * @n: the number of bits to shift by
+ */
+static inline void cpumask_shift_right(struct cpumask *dstp,
+ const struct cpumask *srcp, int n)
+{
+ bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
+ nr_cpumask_bits);
+}
+
+/**
+ * cpumask_shift_left - *dstp = *srcp << n
+ * @dstp: the cpumask result
+ * @srcp: the input to shift
+ * @n: the number of bits to shift by
+ */
+static inline void cpumask_shift_left(struct cpumask *dstp,
+ const struct cpumask *srcp, int n)
+{
+ bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
+ nr_cpumask_bits);
+}
+
+/**
+ * cpumask_copy - *dstp = *srcp
+ * @dstp: the result
+ * @srcp: the input cpumask
+ */
+static inline void cpumask_copy(struct cpumask *dstp,
+ const struct cpumask *srcp)
+{
+ bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
+ * cpumask_any - pick a "random" cpu from *srcp
+ * @srcp: the input cpumask
+ *
+ * Returns >= nr_cpu_ids if no cpus set.
+ */
+#define cpumask_any(srcp) cpumask_first(srcp)
+
+/**
+ * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
+ * @src1p: the first input
+ * @src2p: the second input
+ *
+ * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
+ */
+#define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
+
+/**
+ * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
+ * @mask1: the first input cpumask
+ * @mask2: the second input cpumask
+ *
+ * Returns >= nr_cpu_ids if no cpus set.
+ */
+#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
+
+/**
+ * cpumask_of - the cpumask containing just a given cpu
+ * @cpu: the cpu (<= nr_cpu_ids)
+ */
+#define cpumask_of(cpu) (get_cpu_mask(cpu))
+
+/**
+ * cpumask_parse_user - extract a cpumask from a user string
+ * @buf: the buffer to extract from
+ * @len: the length of the buffer
+ * @dstp: the cpumask to set.
+ *
+ * Returns -errno, or 0 for success.
+ */
+static inline int cpumask_parse_user(const char __user *buf, int len,
+ struct cpumask *dstp)
+{
+ return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpu_ids);
+}
+
+/**
+ * cpumask_parselist_user - extract a cpumask from a user string
+ * @buf: the buffer to extract from
+ * @len: the length of the buffer
+ * @dstp: the cpumask to set.
+ *
+ * Returns -errno, or 0 for success.
+ */
+static inline int cpumask_parselist_user(const char __user *buf, int len,
+ struct cpumask *dstp)
+{
+ return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
+ nr_cpu_ids);
+}
+
+/**
+ * cpumask_parse - extract a cpumask from from a string
+ * @buf: the buffer to extract from
+ * @dstp: the cpumask to set.
+ *
+ * Returns -errno, or 0 for success.
+ */
+static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
+{
+ char *nl = strchr(buf, '\n');
+ unsigned int len = nl ? (unsigned int)(nl - buf) : strlen(buf);
+
+ return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpu_ids);
+}
+
+/**
+ * cpulist_parse - extract a cpumask from a user string of ranges
+ * @buf: the buffer to extract from
+ * @dstp: the cpumask to set.
+ *
+ * Returns -errno, or 0 for success.
+ */
+static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
+{
+ return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpu_ids);
+}
+
+/**
+ * cpumask_size - size to allocate for a 'struct cpumask' in bytes
+ *
+ * This will eventually be a runtime variable, depending on nr_cpu_ids.
+ */
+static inline size_t cpumask_size(void)
+{
+ return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
+}
+
+/*
+ * cpumask_var_t: struct cpumask for stack usage.
+ *
+ * Oh, the wicked games we play! In order to make kernel coding a
+ * 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.
+ * cpumask_var_t tmpmask;
+ * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
+ * return -ENOMEM;
+ *
+ * ... use 'tmpmask' like a normal struct cpumask * ...
+ *
+ * free_cpumask_var(tmpmask);
+ *
+ *
+ * However, one notable exception is there. alloc_cpumask_var() allocates
+ * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
+ * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
+ *
+ * cpumask_var_t tmpmask;
+ * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
+ * return -ENOMEM;
+ *
+ * var = *tmpmask;
+ *
+ * This code makes NR_CPUS length memcopy and brings to a memory corruption.
+ * cpumask_copy() provide safe copy functionality.
+ *
+ * Note that there is another evil here: If you define a cpumask_var_t
+ * as a percpu variable then the way to obtain the address of the cpumask
+ * structure differently influences what this_cpu_* operation needs to be
+ * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
+ * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
+ * other type of cpumask_var_t implementation is configured.
+ */
+#ifdef CONFIG_CPUMASK_OFFSTACK
+typedef struct cpumask *cpumask_var_t;
+
+#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
+
+bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
+bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
+bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
+bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
+void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
+void free_cpumask_var(cpumask_var_t mask);
+void free_bootmem_cpumask_var(cpumask_var_t mask);
+
+#else
+typedef struct cpumask cpumask_var_t[1];
+
+#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
+
+static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+ return true;
+}
+
+static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
+ int node)
+{
+ return true;
+}
+
+static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+ cpumask_clear(*mask);
+ return true;
+}
+
+static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
+ int node)
+{
+ cpumask_clear(*mask);
+ return true;
+}
+
+static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
+{
+}
+
+static inline void free_cpumask_var(cpumask_var_t mask)
+{
+}
+
+static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
+{
+}
+#endif /* CONFIG_CPUMASK_OFFSTACK */
+
+/* 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);
+#define cpu_all_mask to_cpumask(cpu_all_bits)
+
+/* First bits of cpu_bit_bitmap are in fact unset. */
+#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
+
+#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)
+
+/* Wrappers for arch boot code to manipulate normally-constant masks */
+void set_cpu_possible(unsigned int cpu, bool possible);
+void set_cpu_present(unsigned int cpu, bool present);
+void set_cpu_online(unsigned int cpu, bool online);
+void set_cpu_active(unsigned int cpu, bool active);
+void init_cpu_present(const struct cpumask *src);
+void init_cpu_possible(const struct cpumask *src);
+void init_cpu_online(const struct cpumask *src);
+
+/**
+ * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
+ * @bitmap: the bitmap
+ *
+ * There are a few places where cpumask_var_t isn't appropriate and
+ * static cpumasks must be used (eg. very early boot), yet we don't
+ * expose the definition of 'struct cpumask'.
+ *
+ * This does the conversion, and can be used as a constant initializer.
+ */
+#define to_cpumask(bitmap) \
+ ((struct cpumask *)(1 ? (bitmap) \
+ : (void *)sizeof(__check_is_bitmap(bitmap))))
+
+static inline int __check_is_bitmap(const unsigned long *bitmap)
+{
+ return 1;
+}
+
+/*
+ * 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)];
+
+static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
+{
+ const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
+ p -= cpu / BITS_PER_LONG;
+ return to_cpumask(p);
+}
+
+#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
+
+#if NR_CPUS <= BITS_PER_LONG
+#define CPU_BITS_ALL \
+{ \
+ [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
+}
+
+#else /* NR_CPUS > BITS_PER_LONG */
+
+#define CPU_BITS_ALL \
+{ \
+ [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
+ [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
+}
+#endif /* NR_CPUS > BITS_PER_LONG */
+
+/**
+ * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
+ * as comma-separated list of cpus or hex values of cpumask
+ * @list: indicates whether the cpumap must be list
+ * @mask: the cpumask to copy
+ * @buf: the buffer to copy into
+ *
+ * Returns the length of the (null-terminated) @buf string, zero if
+ * nothing is copied.
+ */
+static inline ssize_t
+cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
+{
+ return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
+ nr_cpu_ids);
+}
+
+#if NR_CPUS <= BITS_PER_LONG
+#define CPU_MASK_ALL \
+(cpumask_t) { { \
+ [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
+} }
+#else
+#define CPU_MASK_ALL \
+(cpumask_t) { { \
+ [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
+ [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
+} }
+#endif /* NR_CPUS > BITS_PER_LONG */
+
+#define CPU_MASK_NONE \
+(cpumask_t) { { \
+ [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
+} }
+
+#define CPU_MASK_CPU0 \
+(cpumask_t) { { \
+ [0] = 1UL \
+} }
+
+#endif /* __LINUX_CPUMASK_H */