On Mon, 07 May 2001 12:37:22 -0700 (PDT),
  John Baldwin <[EMAIL PROTECTED]> said:

John> You need the lock when clearing the bit in p_flag.  That is why the proc locks
John> are there, so all those proc locks need to stay.  When you clear a bit, you are
John> writing all the bits, so you need to ensure that you can atomically
John> read/modify/write all the bits in p_flag, hence the need for the proc lock.

As we now have a set of atomic operation functions in
machine/atomic.h, why do we not use them to read, modify and write
p_flag atomically? Is that more expensive than protecting by PROC_LOCK
and PROC_UNLOCK?

-- 
Seigo Tanimura <[EMAIL PROTECTED]> <[EMAIL PROTECTED]>

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