Commit 32342701 authored by Eric W. Biederman's avatar Eric W. Biederman
Browse files

ucounts: Use atomic_long_sub_return for clarity 



Decrement ucounts using atomic_long_sub_return to make it
clear the point is for the ucount to decrease.

Not a big deal but it should make it easier to catch bugs.

Suggested-by: default avatarYu Zhao <yuzhao@google.com>
Link: https://lkml.kernel.org/r/87k0iaqkqj.fsf_-_@disp2133


Tested-by: default avatarYu Zhao <yuzhao@google.com>
Reviewed-by: default avatarAlexey Gladkov <legion@kernel.org>
Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
parent da70d310

kernel/ucount.c

+3 −3
Original line number Diff line number Diff line
@@ -282,7 +282,7 @@ bool dec_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v) 
	struct ucounts *iter;

	long new = -1; /* Silence compiler warning */

	for (iter = ucounts; iter; iter = iter->ns->ucounts) {

		long dec = atomic_long_add_return(-v, &iter->ucount[type]);

		long dec = atomic_long_sub_return(v, &iter->ucount[type]);

		WARN_ON_ONCE(dec < 0);

		if (iter == ucounts)

			new = dec;
@@ -295,7 +295,7 @@ static void do_dec_rlimit_put_ucounts(struct ucounts *ucounts, 
{

	struct ucounts *iter, *next;

	for (iter = ucounts; iter != last; iter = next) {

		long dec = atomic_long_add_return(-1, &iter->ucount[type]);

		long dec = atomic_long_sub_return(1, &iter->ucount[type]);

		WARN_ON_ONCE(dec < 0);

		next = iter->ns->ucounts;

		if (dec == 0)
@@ -332,7 +332,7 @@ long inc_rlimit_get_ucounts(struct ucounts *ucounts, enum ucount_type type) 
	}

	return ret;

dec_unwind:

	dec = atomic_long_add_return(-1, &iter->ucount[type]);

	dec = atomic_long_sub_return(1, &iter->ucount[type]);

	WARN_ON_ONCE(dec < 0);

unwind:

	do_dec_rlimit_put_ucounts(ucounts, iter, type);