maintaining CRYPTO_TIMING

[Daniel Ebdrup Jensen]

On Fri, Jun 12, 2020 at 12:14:01PM -0400, Mark Johnston wrote:
>Hi,
>
>I noticed that the opencrypto framework maintains counters for various
>operations.  These counters are all global and are updated
>non-atomically, so they aren't SMP-friendly and won't be precise.  I
>wrote a patch to convert them to counter(9), which fixes both issues,
>and I note that kern.crypto_stats was renamed to kern.crypto.stats in
>HEAD so presumably we can use this opportunity to break the sysctl ABI
>as well (the counters have to be widened from 32 bits to 64 bits).
>Nothing in the base system seems to actually fetch these counters
>outside of some code under tools/, which wasn't updated when the sysctl
>was renamed.
>
>There is also CRYPTO_TIMING, which attempts to measure the time elapsed
>during various stages of cryptop processing.  This similarly assumes
>that processing is single-threaded and I guess is really only useful to
>OCF driver developers.  It has been in the tree for a very long time,
>but has anyone actually used it?  I would like to remove it since it
>complicates the above-mentioned patch and is of limited usefulness in
>SMP systems.  DTrace or some per-cryptop scheme could be used instead if
>it is really worth having that functionality, but I don't want to write
>a patch to implement that unless someone really wants it.
>_______________________________________________
>freebsd-hackers at freebsd.org mailing list
>https://lists.freebsd.org/mailman/listinfo/freebsd-hackers
>To unsubscribe, send any mail to "freebsd-hackers-unsubscribe at freebsd.org"

I mean, I really like dtrace, but I won't _force_ you to write it.
I'll just applaud loudly if you do. :)

Yours,
Daniel Ebdrup Jensen
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 618 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-hackers/attachments/20200612/e28ada18/attachment.sig>