benno at ok-labs.com
Mon Apr 30 05:31:48 CEST 2007
On Wed Apr 25, 2007 at 18:50:21 -0700, Peter Nguyen wrote:
>OK, so with that in mind, where does the polling take place? I might be
>wrong in saying this, but is there a portion of code that deals directly
>with the polling of I/O? The reason i ask this is that i think that the
>polling of I/O has an affect on the performance monitoring facilities, more
>specifically when a performance counter overflows. This would, in turn,
>have an affect on the ability to take samples given that samples might not
>be taken while waiting for input.
On our kernel this happens within the kernel itself. There is also a
non-blocking version which allows you to perform the polling at
user-level itself. I would suggest you do this which would possibly
avoid the problems you are seeing.
More information about the l4-hackers