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MFC r341095:

Description

MFC r341095:

Use busdma unconditionally in iflib

- Remove the complex mechanism to choose between using busdma
and raw pmap_kextract at runtime.   The reduced complexity makes
the code easier to read and maintain.

- Fix a bug in the small packet receive path where clusters were
repeatedly mapped but never unmapped. We now store the cluster's
bus address and avoid re-mapping the cluster each time a small
packet is received.

This patch fixes bugs I've seen where ixl(4) will not even
respond to ping without seeing DMAR faults.

I see a small improvement (14%) on packet forwarding tests using
a Haswell based Xeon E5-2697 v3.  Olivier sees a small
regression (-3% to -6%) with lower end hardware.

Reviewed by: mmacy
Sponsored by: Netflix, Inc
Differential Revision: https://reviews.freebsd.org/D17901

Details

Committed
gallatinJan 22 2019, 5:34 PM
Reviewer
mmacy
Differential Revision
D17901: Use busdma unconditionally in iflib
Parents
rS343303: Silence a CI warning regarding the use of strcpy().
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