Revert "Lockless path through afs_linux_dentry_revalidate" 93/11793/8
authorAndrew Deason <adeason@sinenomine.net>
Wed, 4 Mar 2015 20:10:23 +0000 (14:10 -0600)
committerBenjamin Kaduk <kaduk@mit.edu>
Thu, 15 Sep 2016 02:25:48 +0000 (22:25 -0400)
commit74d4fea1683ccd5b4db53709fc2b5053062ea052
tree8d13106ba5b80ba8b955abf8678815215c301875
parenta13ea7038ebe262ba1e5387f4a3b12897bd8822b
Revert "Lockless path through afs_linux_dentry_revalidate"

This reverts commit 3ecd65d3375f0a4fa4c28f9b59cdf6a1f6fd51b8.

This commit made it possible to execute afs_linux_dentry_revalidate
without taking the GLOCK under some circumstances. However, it
achieved this by examining structure members outside of the GLOCK that
were previously only examined under the GLOCK (such as vcp->f.states
and vcp->f.m.DataVersion).

While that does of course improve performance, it is not known to be
completely safe. Revert this commit so we may implement a fastpath
through afs_linux_dentry_revalidate using more trusted lockless
techniques (atomics, RCU, etc).

Change-Id: Ia3ca2cf53f97244e4e548db7c1caf218c16aca5c
Reviewed-on: https://gerrit.openafs.org/11793
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
src/afs/LINUX/osi_vnodeops.c