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Subject: Re: kernel function probe overhead
To: Aubrey Li <aubreylee@gmail.com>, "Frank Ch. Eigler" <fche@redhat.com>
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From: Josh Stone <jistone@redhat.com>
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On 11/28/2016 07:30 PM, Aubrey Li wrote:
>> Another solution would be to have per-thread global variables.  Since
>> > the kernel doesn't help us out with this, we'd have to emulate it
>> > somehow, and for this to be wortwhile, it'd have to work faster than
>> > ordinary locked/shared array[tid()] accesses.
>> >
> Is this a suggestion for me? How to do this?

There are relevant RFEs for stap already:

per-cpu: https://sourceware.org/bugzilla/show_bug.cgi?id=10795
per-thread: https://sourceware.org/bugzilla/show_bug.cgi?id=10796

The latter was closed on the hunch that it wouldn't help much, but that
could still be explored if someone is interested.