tree 58ba5b778b6cb26bcafe52fb7034480a4c68af45
parent b650738cd093a9f9e9551db9ce5cd68acd842dc0
author Bob Peterson <rpeterso@redhat.com> 1408553085 -0400
committer Steven Whitehouse <swhiteho@redhat.com> 1408612972 +0100

GFS2: Request demote when a "try" flock fails

This patch changes the flock code so that it uses the TRY_1CB flag
instead of the TRY flag on the first attempt. That forces any holding
nodes to issue a dlm callback, which requests a demote of the glock.
Then, if the "try" failed, it sleeps a small amount of time for the
demote to occur. Then it tries again, for an increasing amount of time.
Subsequent attempts to gain the "try" lock don't use "_1CB" so that
only one callback is issued.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>