On 2/7/07, Rusty Russell <[EMAIL PROTECTED]> wrote:
On Wed, 2007-02-07 at 12:35 +0000, Pavel Machek wrote:
> Ugh, it sounds like paravirt is more b0rken then I thought. It should
> always to the proper delay, then replace those udelays that are not
> needed on virtualized hardware with something else.
>
> Just magically defining udelay into nop is broken.
We'd have to audit and figure out what udelays are for hardware and
which are not, but the evidence is that the vast majority of them are
for hardware and not needed for virtualization.
Changing udelay to "hardware_udelay" or something all over the kernel
would have delayed the paravirt_ops merge by an infinite amount 8)
However I am not really fond of idea of adding constructs like this
all over the code:
#define USE_REAL_TIME_DELAY_I_REALLY_MEAN_IT_THIS_TIME_I_SWEAR
as the time passes... Drivers should be blissfully ignorant of being
run on virtual hardware.
--
Dmitry
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