Messages in this thread | | | From | Rusty Russell <> | Subject | CPU Hotplug: Hotplug Script And SIGPWR | Date | Tue, 20 Jan 2004 16:44:45 +1100 |
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In message <20040116174446.A2820@in.ibm.com> you write: > Would it make sense if we defer invoking hotplug script _after_ > the CPU is completely dead (i.e after issuing the CPU_DEAD > notification)?
The original code wanted to block until the hotplug script acknowledged the removal before completing it. Greg KH says hotplug doesn't work this way, so now it could well be delivered after everything is over. If it's simpler, we can just do it after.
The other issue I wanted to revisit: we currently send SIGPWR to all processes which we have to undo the CPU affinity for (with a new si_info field containing the cpu going down).
The main problem is that a process can call sched_setaffinity on another (unrelated) task, which might not know about it. One option would be to only deliver the signal if it's not SIG_DFL for that process. Another would be not to signal, and expect hotplug scripts to clean up.
Thoughts? Rusty. -- Anyone who quotes me in their sig is an idiot. -- Rusty Russell. - 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/
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