From: Shuah Khan <skhan@linuxfoundation.org>
To: idryomov@gmail.com, dongsheng.yang@easystack.cn, axboe@kernel.dk
Cc: ceph-devel@vger.kernel.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Shuah Khan <skhan@linuxfoundation.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Kees Cook <keescook@chromium.org>
Subject: drivers/block/rbd.c: atomic_inc_return_safe() & atomic_dec_return_safe()
Date: Fri, 2 Oct 2020 16:34:40 -0600 [thread overview]
Message-ID: <ce2dbec5-00f8-831b-3138-cc4f3b8fdb51@linuxfoundation.org> (raw)
All,
I came across these atomic_inc_return_safe() & atomic_dec_return_safe()
functions that hold the counters at safe values.
atomic_inc_return_safe()
If the counter is already 0 it will not be incremented.
If the counter is already at its maximum value returns
-EINVAL without updating it.
atomic_dec_return_safe()
Decrement the counter. Return the resulting value, or -EINVAL
These two routines are static and only used in rbd.c.
Can these become part of atomic_t ops?
thanks,
-- Shuah
next reply other threads:[~2020-10-02 22:34 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-02 22:34 Shuah Khan [this message]
2020-10-02 23:44 ` drivers/block/rbd.c: atomic_inc_return_safe() & atomic_dec_return_safe() Jens Axboe
2020-10-02 23:50 ` Shuah Khan
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