From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Date: Tue, 24 Jan 2006 22:19:15 +0000
Subject: RE: [PATCH] SN2 user-MMIO CPU migration
Message-Id: <200601242219.k0OMJFg15207@unix-os.sc.intel.com>
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References: <20060118163305.Y42462@chenjesu.americas.sgi.com>
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To: linux-ia64@vger.kernel.org

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