From 1470afefc3c42df5d1662f87d079b46651bdc95b Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Wed, 15 Mar 2023 17:31:02 -0700 Subject: cpumask: introduce for_each_cpu_or Equivalent of for_each_cpu_and, except it ORs the two masks together so it iterates all the CPUs present in either mask. Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/cpumask.h | 17 +++++++++++++++++ include/linux/find.h | 37 +++++++++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+) (limited to 'include') diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 8fbe76607965..220974ef1bf5 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -350,6 +350,23 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta #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. * @mask: the cpumask to search diff --git a/include/linux/find.h b/include/linux/find.h index 4647864a5ffd..5e4f39ef2e72 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -14,6 +14,8 @@ unsigned long _find_next_and_bit(const unsigned long *addr1, const unsigned long unsigned long nbits, unsigned long start); unsigned long _find_next_andnot_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long nbits, unsigned long start); +unsigned long _find_next_or_bit(const unsigned long *addr1, const unsigned long *addr2, + unsigned long nbits, unsigned long start); unsigned long _find_next_zero_bit(const unsigned long *addr, unsigned long nbits, unsigned long start); extern unsigned long _find_first_bit(const unsigned long *addr, unsigned long size); @@ -127,6 +129,36 @@ unsigned long find_next_andnot_bit(const unsigned long *addr1, } #endif +#ifndef find_next_or_bit +/** + * find_next_or_bit - find the next set bit in either memory regions + * @addr1: The first address to base the search on + * @addr2: The second address to base the search on + * @size: The bitmap size in bits + * @offset: The bitnumber to start searching at + * + * Returns the bit number for the next set bit + * If no bits are set, returns @size. + */ +static inline +unsigned long find_next_or_bit(const unsigned long *addr1, + const unsigned long *addr2, unsigned long size, + unsigned long offset) +{ + if (small_const_nbits(size)) { + unsigned long val; + + if (unlikely(offset >= size)) + return size; + + val = (*addr1 | *addr2) & GENMASK(size - 1, offset); + return val ? __ffs(val) : size; + } + + return _find_next_or_bit(addr1, addr2, size, offset); +} +#endif + #ifndef find_next_zero_bit /** * find_next_zero_bit - find the next cleared bit in a memory region @@ -536,6 +568,11 @@ unsigned long find_next_bit_le(const void *addr, unsigned (bit) = find_next_andnot_bit((addr1), (addr2), (size), (bit)), (bit) < (size);\ (bit)++) +#define for_each_or_bit(bit, addr1, addr2, size) \ + for ((bit) = 0; \ + (bit) = find_next_or_bit((addr1), (addr2), (size), (bit)), (bit) < (size);\ + (bit)++) + /* same as for_each_set_bit() but use bit as value to start with */ #define for_each_set_bit_from(bit, addr, size) \ for (; (bit) = find_next_bit((addr), (size), (bit)), (bit) < (size); (bit)++) -- cgit v1.2.3-58-ga151 From e9b60c7f97130795c7aa81a649ae4b93a172a277 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Wed, 15 Mar 2023 17:31:03 -0700 Subject: pcpcntr: remove percpu_counter_sum_all() percpu_counter_sum_all() is now redundant as the race condition it was invented to handle is now dealt with by percpu_counter_sum() directly and all users of percpu_counter_sum_all() have been removed. Remove it. This effectively reverts the changes made in f689054aace2 ("percpu_counter: add percpu_counter_sum_all interface") except for the cpumask iteration that fixes percpu_counter_sum() made earlier in this series. Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/percpu_counter.h | 6 ------ lib/percpu_counter.c | 40 +++++++++++----------------------------- 2 files changed, 11 insertions(+), 35 deletions(-) (limited to 'include') diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h index 521a733e21a9..75b73c83bc9d 100644 --- a/include/linux/percpu_counter.h +++ b/include/linux/percpu_counter.h @@ -45,7 +45,6 @@ void percpu_counter_set(struct percpu_counter *fbc, s64 amount); void percpu_counter_add_batch(struct percpu_counter *fbc, s64 amount, s32 batch); s64 __percpu_counter_sum(struct percpu_counter *fbc); -s64 percpu_counter_sum_all(struct percpu_counter *fbc); int __percpu_counter_compare(struct percpu_counter *fbc, s64 rhs, s32 batch); void percpu_counter_sync(struct percpu_counter *fbc); @@ -196,11 +195,6 @@ static inline s64 percpu_counter_sum(struct percpu_counter *fbc) return percpu_counter_read(fbc); } -static inline s64 percpu_counter_sum_all(struct percpu_counter *fbc) -{ - return percpu_counter_read(fbc); -} - static inline bool percpu_counter_initialized(struct percpu_counter *fbc) { return true; diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index 0e096311e0c0..5004463c4f9f 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -122,23 +122,6 @@ void percpu_counter_sync(struct percpu_counter *fbc) } EXPORT_SYMBOL(percpu_counter_sync); -static s64 __percpu_counter_sum_mask(struct percpu_counter *fbc, - const struct cpumask *cpu_mask) -{ - s64 ret; - int cpu; - unsigned long flags; - - raw_spin_lock_irqsave(&fbc->lock, flags); - ret = fbc->count; - for_each_cpu_or(cpu, cpu_online_mask, cpu_mask) { - s32 *pcount = per_cpu_ptr(fbc->counters, cpu); - ret += *pcount; - } - raw_spin_unlock_irqrestore(&fbc->lock, flags); - return ret; -} - /* * Add up all the per-cpu counts, return the result. This is a more accurate * but much slower version of percpu_counter_read_positive(). @@ -153,22 +136,21 @@ static s64 __percpu_counter_sum_mask(struct percpu_counter *fbc, */ s64 __percpu_counter_sum(struct percpu_counter *fbc) { + s64 ret; + int cpu; + unsigned long flags; - return __percpu_counter_sum_mask(fbc, cpu_dying_mask); + raw_spin_lock_irqsave(&fbc->lock, flags); + ret = fbc->count; + for_each_cpu_or(cpu, cpu_online_mask, cpu_dying_mask) { + s32 *pcount = per_cpu_ptr(fbc->counters, cpu); + ret += *pcount; + } + raw_spin_unlock_irqrestore(&fbc->lock, flags); + return ret; } EXPORT_SYMBOL(__percpu_counter_sum); -/* - * This is slower version of percpu_counter_sum as it traverses all possible - * cpus. Use this only in the cases where accurate data is needed in the - * presense of CPUs getting offlined. - */ -s64 percpu_counter_sum_all(struct percpu_counter *fbc) -{ - return __percpu_counter_sum_mask(fbc, cpu_possible_mask); -} -EXPORT_SYMBOL(percpu_counter_sum_all); - int __percpu_counter_init(struct percpu_counter *fbc, s64 amount, gfp_t gfp, struct lock_class_key *key) { -- cgit v1.2.3-58-ga151