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Re: better SMP support for kprobes




Martin Hunt wrote:
Currently kprobe_handler grabs kprobe_lock and keeps it the entire time
the probe is executing.  On SMP systems this could cause significant
performance degradation because only one cpu can be executing a kprobe;
all others will be blocked.

Has anyone looked at fixing this?  Based on a quick read of the code, I
see the kprobe_lock is needed to protect access to the kprobe_table.
There are also a bunch of globals that could be implemented as per_cpu
data. Anyone want to volunteer to take a closer look?

Martin



I have looked a little at this and looked into per cpu data to avoid this problem. I can volunteer for it.


-Will


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