Add options to dmb() and dsb() macros
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Authored by zbb on Jun 1 2015, 12:14 AM.

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Reviewers

emaste
andrew
imp
• ian

Summary

Using plain dsb()/dmb() as full system barriers is usually to much.
Adding proper options to those barriers (instead of full system - sy)
will most likely reduce the cost of the instructions and will benefit
in performance improvement.
This commit adds options to barrier macro definitions.

Obtained from: Semihalf
Sponsored by: The FreeBSD Foundation

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zbb updated this revision to Diff 5849.Jun 1 2015, 12:14 AM

zbb retitled this revision from to Add options to dmb() and dsb() macros.

zbb updated this object.

zbb edited the test plan for this revision. (Show Details)

zbb added reviewers: andrew, emaste, imp, • ian.

zbb set the repository for this revision to rS FreeBSD src repository - subversion.

zbb added a subscriber: Unknown Object (MLST).

Herald added subscribers: imp, andrew, emaste. · View Herald TranscriptJun 1 2015, 12:14 AM

zbb added a child revision: D2378: Introduce ITS support for ARM64.Jun 1 2015, 12:15 AM

Given you are changing these can you also mark them as with ish*?

sys/arm64/arm64/db_interface.c
164–165	Are these needed? The cache handling functions already have dsb and isb instructions.
sys/arm64/include/atomic.h
32	This should be `#define<tab>isb()...`
49–54	And these

Is this really all the instances of dmb() and dsb() in the code? I guess most of them must be in asm and inline-asm code.

This revision is now accepted and ready to land.Jun 6 2015, 8:05 PM

Thank you!

In D2701#52274, @ian wrote:

Is this really all the instances of dmb() and dsb() in the code? I guess most of them must be in asm and inline-asm code.

Yes, however there will be some more in the ITS code.

Thank you very much. Committed to r284196.
https://svnweb.freebsd.org/changeset/base/284196