On Wed, Oct 18, 2017 at 4:10 AM, Michael Kerrisk (man-pages) <mtk.manpages@xxxxxxxxx> wrote: > Hello all, > > I recently drafted a manual page for the pthread_spin_init() and > pthread_spin_destroy() APIs. Comments and suggestions for improvements > would be most welcome. This should probably cross-reference the pthread_mutex_* manpages and say when it is appropriate to use which. I see you already have some of that... > NOTES > Spin locks should be employed in conjunction with real-time sched‐ > uling policies (SCHED_FIFO, or possibly SCHED_RR). Use of spin > locks with nondeterministic scheduling policies such as > SCHED_OTHER probably indicates a design mistake. The problem is > that if a thread operating under such a policy is scheduled off > the CPU while it holds a spin lock, then other threads will waste > time spinning on the lock until the lock holder is once more > rescheduled and releases the lock. > > Warning: if threads create a deadlock situation while employing > spin locks, those threads will spin forever consuming CPU time. but you might want to begin with something like "Most programs should use mutexes (pthread_mutex_init(3)) instead of spin locks. Spin locks are primarily useful in conjunction with real-time scheduling ..." Also, this is important enough that I'd put it in the DESCRIPTION. zw -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
