Blackfin: allow high priority domains to preempt schedule_tail()
Blackfin: allow high priority domains to preempt schedule_tail()

ret_from_fork is always entered with hw interrupts off, which prevents
real-time domains to preempt the Linux kernel during part of the
initial context switch to the new task, which could in turn raise the
worst-case latency figures.

To avoid this, stall the root domain stage in the interrupt pipeline
to keep the scheduling tail code free from Linux-handled IRQs, then
enable hardware interrupts again.

Signed-off-by: Philippe Gerum <d839ee45896e6fd6af263edfd34014da50964f0b@xenomai.org>
Signed-off-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@gentoo.org>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas