K 10
svn:author
V 2
kp
K 8
svn:date
V 27
2020-04-26T16:22:35.610353Z
K 7
svn:log
V 549
bridge: epoch-ification

Run the bridge datapath under epoch, rather than under the
BRIDGE_LOCK().

We still take the BRIDGE_LOCK() whenever we insert or delete items in
the relevant lists, but we use epoch callbacks to free items so that
it's safe to iterate the lists without the BRIDGE_LOCK.

Tests on mercat5/6 shows this increases bridge throughput significantly,
from 3.7Mpps to 18.6Mpps.

Reviewed by:	emaste, philip, melifaro
MFC after:	2 months
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D24250

END