tree c9992cccbc6bcb2f099395ef614ebc96b91a2598
parent 9ee79a3d372fcb6729893437f4923c5efd1f85db
author Ralf Baechle <ralf@linux-mips.org> 1169252281 +0000
committer Ralf Baechle <ralf@linux-mips.org> 1169576807 +0000

[MIPS] SMTC: Instant IPI replay.

SMTC pseudo-interrupts between TCs are deferred and queued if the target
TC is interrupt-inhibited (IXMT). In the first SMTC prototypes, these
queued IPIs were serviced on return to user mode, or on entry into the
kernel idle loop. The INSTANT_REPLAY option dispatches them as part of
local_irq_restore() processing, which adds runtime overhead (hence the
option to turn it off), but ensures that IPIs are handled promptly even
under heavy I/O interrupt load.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>