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author | 2007-09-27 15:53:38 -0500 | |
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committer | 2007-10-10 08:56:38 +0100 | |
commit | c36258b5925e6cf6bf72904635100593573bfcff (patch) | |
tree | 565f1ce29a7f8a2cd1c25f2d36c932727adbdbc2 /fs/dlm/dlm_internal.h | |
parent | [DLM] don't overwrite castparam if it's NULL (diff) | |
download | linux-c36258b5925e6cf6bf72904635100593573bfcff.tar.gz linux-c36258b5925e6cf6bf72904635100593573bfcff.tar.bz2 linux-c36258b5925e6cf6bf72904635100593573bfcff.zip |
[DLM] block dlm_recv in recovery transition
Introduce a per-lockspace rwsem that's held in read mode by dlm_recv
threads while working in the dlm. This allows dlm_recv activity to be
suspended when the lockspace transitions to, from and between recovery
cycles.
The specific bug prompting this change is one where an in-progress
recovery cycle is aborted by a new recovery cycle. While dlm_recv was
processing a recovery message, the recovery cycle was aborted and
dlm_recoverd began cleaning up. dlm_recv decremented recover_locks_count
on an rsb after dlm_recoverd had reset it to zero. This is fixed by
suspending dlm_recv (taking write lock on the rwsem) before aborting the
current recovery.
The transitions to/from normal and recovery modes are simplified by using
this new ability to block dlm_recv. The switch from normal to recovery
mode means dlm_recv goes from processing locking messages, to saving them
for later, and vice versa. Races are avoided by blocking dlm_recv when
setting the flag that switches between modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/dlm/dlm_internal.h')
-rw-r--r-- | fs/dlm/dlm_internal.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h index 74901e981e10..d2fc2384c3be 100644 --- a/fs/dlm/dlm_internal.h +++ b/fs/dlm/dlm_internal.h @@ -491,6 +491,7 @@ struct dlm_ls { uint64_t ls_recover_seq; struct dlm_recover *ls_recover_args; struct rw_semaphore ls_in_recovery; /* block local requests */ + struct rw_semaphore ls_recv_active; /* block dlm_recv */ struct list_head ls_requestqueue;/* queue remote requests */ struct mutex ls_requestqueue_mutex; char *ls_recover_buf; |