thanks for making this patch, it looks good just few minor changes about comments
On 7/23/2010 5:15 AM, Wengang Wang wrote: > In the following situation, there remains an incorrect bit in refmap on the > recovery master. Finally the recovery master will fail at purging the lockres > due to the incorrect bit in refmap. > > 1) node A has no interest on lockres A any longer, so it is purging it. > 2) the owner of lockres A is node B, so node A is sending de-ref message > to node B. > 3) at this time, node B crashed. node C becomes the recovery master. it > recovers > lockres A(because the master is the dead node B). > 4) node A migrated lockres A to node C with a refbit there. > 5) node A failed to send de-ref message to node B because it crashed. The > failure > is ignored. no other action is done for lockres A any more. > > For mormal, re-send the deref message to it to recovery master can fix it. > Well, > ignoring the failure of deref to the original master and not recovering the > lockres > to recovery master has the same effect. And the later is simpler. > > Signed-off-by: Wengang Wang <[email protected]> > --- > fs/ocfs2/dlm/dlmrecovery.c | 17 +++++++++++++++-- > fs/ocfs2/dlm/dlmthread.c | 28 +++++++++++++++++----------- > 2 files changed, 32 insertions(+), 13 deletions(-) > > diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c > index 9dfaac7..06640f6 100644 > --- a/fs/ocfs2/dlm/dlmrecovery.c > +++ b/fs/ocfs2/dlm/dlmrecovery.c > @@ -1997,6 +1997,8 @@ void dlm_move_lockres_to_recovery_list(struct dlm_ctxt > *dlm, > struct list_head *queue; > struct dlm_lock *lock, *next; > > + assert_spin_locked(&dlm->spinlock); > + assert_spin_locked(&res->spinlock); > res->state |= DLM_LOCK_RES_RECOVERING; > if (!list_empty(&res->recovering)) { > mlog(0, > @@ -2336,9 +2338,20 @@ static void dlm_do_local_recovery_cleanup(struct > dlm_ctxt *dlm, u8 dead_node) > > /* the wake_up for this will happen when the > * RECOVERING flag is dropped later */ > remove above comment as it doesn't seem to be relevant anymore. > - res->state &= ~DLM_LOCK_RES_DROPPING_REF; > + if (res->state & DLM_LOCK_RES_DROPPING_REF) { > + /* > + * don't migrate a lockres which is in > + * progress of dropping ref > + */ > move this comment to before the if condition > + mlog(ML_NOTICE, "%.*s ignored for " > + "migration\n", res->lockname.len, > + res->lockname.name); > This information only helps us in diagnosing any related issue and is not helpful in normal cases. So it should be 0 instead of ML_NOTICE. > + res->state &= > + ~DLM_LOCK_RES_DROPPING_REF; > we don't need to clear this state as dlm_purge_lockres removes it. > + } else > + dlm_move_lockres_to_recovery_list(dlm, > + res); > > - dlm_move_lockres_to_recovery_list(dlm, res); > } else if (res->owner == dlm->node_num) { > dlm_free_dead_locks(dlm, res, dead_node); > __dlm_lockres_calc_usage(dlm, res); > diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c > index dd78ca3..47420ce 100644 > --- a/fs/ocfs2/dlm/dlmthread.c > +++ b/fs/ocfs2/dlm/dlmthread.c > @@ -92,17 +92,23 @@ int __dlm_lockres_has_locks(struct dlm_lock_resource *res) > * truly ready to be freed. */ > int __dlm_lockres_unused(struct dlm_lock_resource *res) > { > - if (!__dlm_lockres_has_locks(res) && > - (list_empty(&res->dirty) && !(res->state & DLM_LOCK_RES_DIRTY))) { > - /* try not to scan the bitmap unless the first two > - * conditions are already true */ > - int bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); > - if (bit >= O2NM_MAX_NODES) { > - /* since the bit for dlm->node_num is not > - * set, inflight_locks better be zero */ > - BUG_ON(res->inflight_locks != 0); > - return 1; > - } > + int bit; > + > + if (__dlm_lockres_has_locks(res)) > + return 0; > + > + if (!list_empty(&res->dirty) || res->state & DLM_LOCK_RES_DIRTY) > + return 0; > + > + if (res->state & DLM_LOCK_RES_RECOVERING) > + return 0; > + > + bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); > + if (bit >= O2NM_MAX_NODES) { > + /* since the bit for dlm->node_num is not > + * set, inflight_locks better be zero */ > + BUG_ON(res->inflight_locks != 0); > + return 1; > } > return 0; > } > _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
