diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index f10fb87d49db..cfb545841a2c 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -4,7 +4,7 @@ /* * 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 @@ -97,7 +97,7 @@ static inline void set_nr_cpu_ids(unsigned int nr) * * 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 @@ -112,7 +112,7 @@ static inline void set_nr_cpu_ids(unsigned int nr) * 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() @@ -155,7 +155,7 @@ static __always_inline unsigned int cpumask_check(unsigned int cpu) * 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) { @@ -166,7 +166,7 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp) * 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) { @@ -178,7 +178,7 @@ static inline unsigned int cpumask_first_zero(const struct cpumask *srcp) * @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) @@ -190,7 +190,7 @@ unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask * 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) { @@ -199,10 +199,10 @@ static inline unsigned int cpumask_last(const struct cpumask *srcp) /** * 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) @@ -215,10 +215,10 @@ unsigned int cpumask_next(int n, const struct cpumask *srcp) /** * 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) { @@ -254,11 +254,11 @@ unsigned int cpumask_any_distribute(const struct cpumask *srcp); /** * 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, @@ -373,7 +373,7 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta * @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) @@ -388,11 +388,11 @@ unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu) } /** - * cpumask_nth - get the first cpu in a cpumask + * cpumask_nth - get the Nth cpu in a cpumask * @srcp: the cpumask pointer - * @cpu: the N'th cpu to find, starting from 0 + * @cpu: the Nth cpu to find, starting from 0 * - * Returns >= nr_cpu_ids if such cpu doesn't exist. + * Return: >= nr_cpu_ids if such cpu doesn't exist. */ static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp) { @@ -400,12 +400,12 @@ static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *s } /** - * cpumask_nth_and - get the first cpu in 2 cpumasks + * cpumask_nth_and - get the Nth cpu in 2 cpumasks * @srcp1: the cpumask pointer * @srcp2: the cpumask pointer - * @cpu: the N'th cpu to find, starting from 0 + * @cpu: the Nth cpu to find, starting from 0 * - * Returns >= nr_cpu_ids if such cpu doesn't exist. + * Return: >= nr_cpu_ids if such cpu doesn't exist. */ static inline unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1, @@ -416,12 +416,12 @@ unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1, } /** - * cpumask_nth_andnot - get the first cpu set in 1st cpumask, and clear in 2nd. + * 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 N'th cpu to find, starting from 0 + * @cpu: the Nth cpu to find, starting from 0 * - * Returns >= nr_cpu_ids if such cpu doesn't exist. + * Return: >= nr_cpu_ids if such cpu doesn't exist. */ static inline unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1, @@ -436,9 +436,9 @@ unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1, * @srcp1: the cpumask pointer * @srcp2: the cpumask pointer * @srcp3: the cpumask pointer - * @cpu: the N'th cpu to find, starting from 0 + * @cpu: the Nth cpu to find, starting from 0 * - * Returns >= nr_cpu_ids if such cpu doesn't exist. + * 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, @@ -497,7 +497,7 @@ static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) * @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) { @@ -509,9 +509,9 @@ static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpum * @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) { @@ -523,9 +523,9 @@ static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cp * @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) { @@ -560,7 +560,7 @@ static inline void cpumask_clear(struct cpumask *dstp) * @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, @@ -603,7 +603,7 @@ static inline void cpumask_xor(struct cpumask *dstp, * @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, @@ -617,6 +617,8 @@ static inline bool cpumask_andnot(struct cpumask *dstp, * 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) @@ -630,6 +632,9 @@ static inline bool cpumask_equal(const struct cpumask *src1p, * @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, @@ -643,6 +648,9 @@ static inline bool cpumask_or_equal(const struct cpumask *src1p, * 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) @@ -656,7 +664,7 @@ static inline bool cpumask_intersects(const struct cpumask *src1p, * @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) @@ -668,6 +676,8 @@ static inline bool cpumask_subset(const struct cpumask *src1p, /** * 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) { @@ -677,6 +687,8 @@ static inline bool cpumask_empty(const struct cpumask *srcp) /** * 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) { @@ -686,6 +698,8 @@ 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) { @@ -696,6 +710,8 @@ static inline unsigned int cpumask_weight(const struct cpumask *srcp) * 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) @@ -744,7 +760,7 @@ static inline void cpumask_copy(struct cpumask *dstp, * 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) @@ -753,7 +769,7 @@ static inline void cpumask_copy(struct cpumask *dstp, * @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)) @@ -769,7 +785,7 @@ static inline void cpumask_copy(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_parse_user(const char __user *buf, int len, struct cpumask *dstp) @@ -783,7 +799,7 @@ static inline int cpumask_parse_user(const char __user *buf, int len, * @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) @@ -797,7 +813,7 @@ static inline int cpumask_parselist_user(const char __user *buf, int len, * @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) { @@ -809,7 +825,7 @@ 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) { @@ -817,7 +833,9 @@ 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) { @@ -831,7 +849,7 @@ static inline unsigned int cpumask_size(void) * 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; @@ -887,6 +905,8 @@ bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node) * a nop returning a constant 1 (in ). * * 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) @@ -1025,7 +1045,7 @@ set_cpu_dying(unsigned int cpu, bool dying) } /** - * 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 @@ -1068,6 +1088,8 @@ static inline const struct cpumask *get_cpu_mask(unsigned int cpu) * 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 __always_inline unsigned int num_online_cpus(void) { @@ -1160,7 +1182,7 @@ static inline bool cpu_dying(unsigned int cpu) * @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 @@ -1183,7 +1205,7 @@ cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) * 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 @@ -1204,6 +1226,9 @@ cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask, * * 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, diff --git a/lib/cpumask.c b/lib/cpumask.c index a7fd02b5ae26..19277c6d551f 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -14,7 +14,7 @@ * @start: the start point of the iteration * @wrap: assume @n crossing @start terminates the iteration * - * Returns >= nr_cpu_ids on completion + * Return: >= nr_cpu_ids on completion * * Note: the @wrap argument is required for the start condition when * we cannot assume @start is set in @mask. @@ -48,8 +48,9 @@ EXPORT_SYMBOL(cpumask_next_wrap); * @node: memory node from which to allocate or %NUMA_NO_NODE * * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is - * a nop returning a constant 1 (in ) - * Returns TRUE if memory allocation succeeded, FALSE otherwise. + * a nop returning a constant 1 (in ). + * + * Return: TRUE if memory allocation succeeded, FALSE otherwise. * * In addition, mask will be NULL if this fails. Note that gcc is * usually smart enough to know that mask can never be NULL if @@ -115,7 +116,7 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask) * @i: index number * @node: local numa_node * - * Returns online CPU according to a numa aware policy; local cpus are returned + * Return: online CPU according to a numa aware policy; local cpus are returned * first, followed by non-local ones, then it wraps around. * * For those who wants to enumerate all CPUs based on their NUMA distances, @@ -165,7 +166,7 @@ static DEFINE_PER_CPU(int, distribute_cpu_mask_prev); * Iterated calls using the same srcp1 and srcp2 will be distributed within * their intersection. * - * Returns >= nr_cpu_ids if the intersection is empty. + * Return: >= nr_cpu_ids if the intersection is empty. */ unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, const struct cpumask *src2p) @@ -184,6 +185,12 @@ unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, } EXPORT_SYMBOL(cpumask_any_and_distribute); +/** + * cpumask_any_distribute - Return an arbitrary cpu from srcp + * @srcp: &cpumask for selection + * + * Return: >= nr_cpu_ids if the intersection is empty. + */ unsigned int cpumask_any_distribute(const struct cpumask *srcp) { unsigned int next, prev;