Messages in this thread |  | | Date | Sun, 7 Oct 2001 22:37:15 +0200 | From | Andrea Arcangeli <> | Subject | Re: [announce] [patch] limiting IRQ load, irq-rewrite-2.4.11-B5 |
| |
Ingo could you explain me one basic thing?
What the hell has the hardirq rate limit logic to do with softirqs?
(btw, I don't know why you call it irq-rewrite, you didn't rewrote anything, you just added a irq flood avoidance feature by lefting irq disabled when you detect an irq flood caming in)
hardirqs have nothing to do with softirqs. Softirq as their name suggest are a totally software thing, they're generated by software, incidentally for the network stack they're posted from hard irq handlers because network cards are irq driven, but that's just a special case (of course it is the common case), but it is not the general case.
Your hardirq rate limit logic that lefts the irq disabled for some time is certainly needed from a security standpoint to avoid DoS if untrusted users can generates a flood of irqs using some device, unless the devices provides a way to flow control the irq rate (which I understood most hardware that can generate a flood of irqs provides anyways).
as far I can tell any change to the softirq logic is completly orthogonal with the softirq changes. Changing both things together or seeing any connection between the two just shows a very limited network oriented view of the whole picture about the softirqs.
Now I'm not saying that I don't want to change anything in the softirq logic, for example the deschedule logic made lots of sense and I can see the benefit for users like the network stack.
Andrea - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |