[lkml]   [2002]   [Sep]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH][RFC] per isr in_progress markers
Zwane Mwaikambo wrote:

>On Mon, 9 Sep 2002, Linus Torvalds wrote:
>>I agree with you, but that is only true for edge-triggered APIC
>>interrupts, though - for level-triggered ones we will just re-take the
>>interrupt when we unmask it again.
>>Which is kind of sad. Is there some fast way to read the status of a
>>level-trigger irq off the IO-APIC in case it is still pending, and to do
>>the mitigation even for level-triggered?
>perhaps Remote IRR might help there?
>>(Btw, if there is, that would also allow us to notice the "constantly
>>screaming PCI interrupt" without help from the low-level isrs)
>As an aside, i just had an idea for another way to improve interrupt
>handling latency. Instead of walking through all the isrs in the chain,
>we can have an isr flag wether it was the source of the irq, and if so we
>stop right there and not walk through the other isrs.
This method is flawed for edge-triggered interrupts: you will miss any
interrupts which come in before you acked the first.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:28    [W:0.079 / U:10.668 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site