[PATCH] hvc_console polling mode timer backoff
miltonm at bga.com
Sun Apr 15 05:42:02 EST 2007
Michael Ellerman wrote:
> + * msleep until we reach the max. This may be noticable as a brief
> + * one second) delay on the console before the console responds to
> input when
> + * there has been no input for sometime.
> + */
> +#define MIN_TIMEOUT (10)
> +#define MAX_TIMEOUT (2000)
> +static u32 timeout = MIN_TIMEOUT;
Did you consider making MAX_TIMEOUT a module parameter? It could then
be changed at runtime through /sys/modules/.
> + if (timeout < MAX_TIMEOUT)
> + timeout += (timeout >> 6) + 1;
Keeping MIN_TIMEOUT a define is okay with me, and the code will
naturally ignore max < MIN. It may overshoot timeout by 1/64th.
I doubt we would worry about the overflow case, because by then
the timeout would have been quite long, and the user would like
it to be short again.
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