On 10/23/2017 07:25 PM, kemi wrote: > > > On 2017年10月24日 09:21, Andi Kleen wrote: >> kemi <kemi.w...@intel.com> writes: >>> >>> I'll see if I can find some >>>> time to implement the above in a nice way. >>> >>> Agree. Maybe something like test_and_set_bit() would be more suitable. >> >> test_and_set_bit is a very different operation for the CPU because >> it is atomic for both. But we want the initial read to not >> be atomic. >> > > I meant to express the meaning of test before setting bit. > Apologize to make you confused.
That's why I suggested something like set_bit_if_not_set(), test_and_set_bit() is both already used and has entirely different semantics. -- Jens Axboe