> Hi,
>
> Why does do_timer() do:
>
> (*(unsigned long *)&jiffies)++;
>
> why not just jiffies++; ? It works fine with jiffies++ but I assume there
> is a reason...
>
> Thanks,
> Tigran.
>
It looks to me like there was an attempt to prevent the 'C' compiler
from doing:
movl jiffies, %eax ! Read
incl %eax ! Modify
movl %eax, jiffies ! Write back
....and such attempts are rarely sucessful.
Ideally, you'd want:
incl jiffies
...and you'd have to do it in assembly to make sure the next 'C' compiler
doesn't out-guess you.
Cheers,
Dick Johnson
Penguin : Linux version 2.3.35 on an i686 machine (400.59 BogoMips).
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