RE: [PATCH] SN2 user-MMIO CPU migration

Chen, Kenneth W
2006-01-24T22:19:15Z

Brent Casavant wrote on Tuesday, January 24, 2006 2:12 PM
> > On the other hand, it may not be too bad because on kernel exit, flags
> > field in thread_info is accessed for TIF_* and if kernel exit path is
> > taken back-to-back with context switch, the net effect maybe small.
>
> Actually, IA64_HAS_EXTRA_STATE() reads the TIF_* flags, and is called
> in __switch_to(), which is in very close proximity to checking last_cpu.

Where??

IA64_HAS_EXTRA_STATE() uses task->thread.flags, not task->thread_info->flags.
These two flags are in two different places.

- Ken