From mboxrd@z Thu Jan  1 00:00:00 1970
From: "zhangsong" <happynodyandhappyyogo@gmail.com>
Subject: Why does he write such code?
Date: Mon, 19 Jan 2009 12:58:49 +0800
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To: linux-newbie@vger.kernel.org

Hello all,=20

I read linux-2.4 and found a line of confused code:

In kernel/sched.c:
      =20
     void do_timer(struct pt_regs * regs)
     {
=A1=A1=A1=A1	   (*(unsigned long *)&jiffies)++; /* confused code */
=A1=A1=A1=A1=A1=A1=A1=A1=A1=AD
     }

1. Why not to use something link atomic_inc insead of the above code?
2. Can the GCC optimize the above code to jiffies++ ?

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