Re: tickle nmi watchdog whilst doing serial writes.

[Arjan van de Ven <arjan@infradead.org>]

On Fri, 2005-05-13 at 14:48 -0400, Dave Jones wrote:
>  	if (up->port.flags & UPF_CONS_FLOW) {
>  		tmout = 1000000;
>  		while (--tmout &&
> -		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
> +		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) {
>  			udelay(1);
> +			touch_nmi_watchdog();
> +		}
>  	}
>  }
>  
> 
> We *could* tickle it less often, but given we're busy waiting anyway
> it probably doesnt make sense to not favour the more simple approach.
> Hmm, maybe we want a cpu_relax() in there too. opinions?

udelay() includes cpu_relax() already so that is futile.

However.. this is a hack. Do we really need to do busy waiting here for
this long??


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