RE: [patch V2 2/5] posix-cpu-timers: Convert the flags to a bitmap

From: Thomas Gleixner
Date: Tue Jul 21 2020 - 14:30:08 EST


David Laight <David.Laight@xxxxxxxxxx> writes:
> From: Thomas Gleixner
>> Sent: 21 July 2020 17:11
>>
>> Frederic Weisbecker <frederic@xxxxxxxxxx> writes:
>> > On Thu, Jul 16, 2020 at 10:19:25PM +0200, Thomas Gleixner wrote:
>> >> --- a/kernel/time/posix-cpu-timers.c
>> >> +++ b/kernel/time/posix-cpu-timers.c
>> >> @@ -25,7 +25,7 @@ void posix_cputimers_group_init(struct p
>> >> posix_cputimers_init(pct);
>> >> if (cpu_limit != RLIM_INFINITY) {
>> >> pct->bases[CPUCLOCK_PROF].nextevt = cpu_limit * NSEC_PER_SEC;
>> >> - pct->timers_active = true;
>> >> + set_bit(CPUTIMERS_ACTIVE, &pct->flags);
>> >
>> > I guess this one could be __set_bit().
>>
>> True :)
>
> Hmmm... does this code need the bit operations to be atmomic?
> If not then an bitmap is completely the wrong thing to be using.

Some of it does, otherwise the booleans would have stayed, but I'm
reworking parts of it so this might change.

Thanks,

tglx