Re: sched_yield() makes OpenLDAP slow

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Howard Chu wrote:

Robert Hancock wrote:

 > This says nothing about requiring a reschedule. The "scheduling policy"
 > can well decide that the thread which just released the mutex can
 > re-acquire it.

No, because the thread that just released the mutex is obviously not one of the threads blocked on the mutex. When a mutex is unlocked, one of the *waiting* threads at the time of the unlock must acquire it, and the scheduling policy can determine that. But the thread the released the mutex is not one of the waiting threads, and is not eligible for consideration.

Is it *required* that the new owner of the mutex is determined at the time of mutex release?

If the kernel doesn't actually determine the new owner of the mutex until the currently running thread swaps out, it would be possible for the currently running thread to re-aquire the mutex.

Chris
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux