Blue Swirl wrote:
On 2/9/08, Rob Landley <[EMAIL PROTECTED]> wrote:
Here's a patch Peter Anvin wrote so the serial I/O doesn't flood the kernel.
The patch looks OK, but the throttling should benefit all devices, as
discussed here:
http://lists.gnu.org/archive/html/qemu-devel/2007-12/msg00283.html
I strongly disagree with the sentiments in that post.
This is not a matter of rate throttling, but simulated FIFO exhaustion
-- they are NOT the same thing. Simulated FIFO exhaustion is
functionally equivalent to making sure there are interrupt windows
opened in an otherwise-too-long critical section; it doesn't constrain
any particular flow rate, as it still permits another interrupt to
immediately come in.
If you look at the patch, there are no timing dependencies; the only
parameter is the depth of the virtual queue. The exhaustion is
completely controlled by target OS access patterns.
-hpa
