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RE: [RFC][Patch 1/4] kprobe fast unregistration

Keshavamurthy, Anil S wrote:
> I agree with Christop that the interface is horrible and error prone.
> However, I see the use case where people want to disable the probes
> quickly and would like to reenable them again. Looking closely at
> your patch, 
> I think this can be acheived.
> Here is my suggestion.
>> Here is an example code.
>> --
>> struct kprobes *p;
>> for_each_probe(p) {
>> 	unregister_kprobe_fast(p);
>         ^^^^^^^^^^^^^^^^^^^^^^
> Change this to disable_kprobe(p), which is essentially the same as
> what you have implemented. And also provide an opposite function
> to reenable_kprobe(p) which enables the disabled probe again.
>> }
>> commit_kprobes();
>   ^^^^^^^^^^^^^^
> Change this to unregister_disabled_kprobes(), which essentially
> unregisters all the disabled probes.

The ability to disable/reenable kprobes would be an interesting
enhancement.  However, unregister_disabled_kprobes() shouldn't have a
global effect, because there might be a concurrent kprobes user that
disabled a probe with the intention of reenabling it later.

Josh Stone

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