Commit e9b60c7f authored by Dave Chinner's avatar Dave Chinner Committed by Darrick J. Wong
Browse files

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 f689054a
("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: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
parent 7ba85fba

include/linux/percpu_counter.h

+0 −6
Original line number Diff line number Diff line
@@ -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;

lib/percpu_counter.c

+11 −29
Original line number Diff line number Diff line
@@ -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().
@@ -153,21 +136,20 @@ 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;

	}

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);

	raw_spin_unlock_irqrestore(&fbc->lock, flags);

	return ret;

}

EXPORT_SYMBOL(percpu_counter_sum_all);

EXPORT_SYMBOL(__percpu_counter_sum);



int __percpu_counter_init(struct percpu_counter *fbc, s64 amount, gfp_t gfp,

			  struct lock_class_key *key)