arijort@valinux.com writes:
> Simple arithmetic tells me this patch
>
> a) produces same behavior as previous code, and
> b) does it with fewer calculations.
>
> So it has to be good, right?
> But then how do we exit the while loop?
> How does jiffies change?
>
> This patch applies cleanly against 2.2.14
> Against 2.3.45, the relevant file is ide.c
> but otherwise, it's clean.
It's also wrong. (HZ + 39)/20 is constant, and you therefore have
effectively a while(1); loop there now.
(Hint: 'jiffies' is updated in an interrupt routine which is enabled
throughout this function).
> --- drivers/block/ide-probe.c.orig Sun Feb 20 00:46:54 2000
> +++ drivers/block/ide-probe.c Sun Feb 20 07:28:32 2000
> @@ -154,8 +154,7 @@
> */
> static void delay_50ms (void)
> {
> - unsigned long timeout = jiffies + ((HZ + 19)/20) + 1;
> - while (0 < (signed long)(timeout - jiffies));
> + while (0 < (signed long)((HZ + 39)/20));
> }
>
> /*
_____
|_____| ------------------------------------------------- ---+---+-
| | Russell King rmk@arm.linux.org.uk --- ---
| | | | http://www.arm.linux.org.uk/~rmk/aboutme.html / / |
| +-+-+ --- -+-
/ | THE developer of ARM Linux |+| /|\
/ | | | --- |
+-+-+ ------------------------------------------------- /\\\ |
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Wed Feb 23 2000 - 21:00:25 EST