Gechangwei
2017-Jan-05 07:44 UTC
[Ocfs2-devel] [PATCH v2 3/3] ocfs2/dlm: continue to purge recovery lockres when recovery master goes down
On 2017/1/5 15:28, gechangwei 12382 (Cloud) wrote: Hi Jun, I suppose that a defect hid your patch.> We found a dlm-blocked situation caused by continuous breakdown of recovery masters described below. To solve this problem, we should purge recovery lock once detecting recovery master goes down. > > N3 N2 N1(reco master) > go down > pick up recovery lock and > begin recoverying for N2 > > go down > > pick up recovery > lock failed, then > purge it: > dlm_purge_lockres > ->DROPPING_REF is set > > send deref to N1 failed, > recovery lock is not purged > > find N1 go down, begin > recoverying for N1, but > blocked in dlm_do_recovery > as DROPPING_REF is set: > dlm_do_recovery > ->dlm_pick_recovery_master > ->dlmlock > ->dlm_get_lock_resource > ->__dlm_wait_on_lockres_flags(tmpres, > DLM_LOCK_RES_DROPPING_REF); > > Fixes: 8c0343968163 ("ocfs2/dlm: clear DROPPING_REF flag when the master goes down") > > Signed-off-by: Jun Piao <piaojun at huawei.com> > Reviewed-by: Joseph Qi <joseph.qi at huawei.com> > Reviewed-by: Jiufei Xue <xuejiufei at huawei.com> > --- > fs/ocfs2/dlm/dlmcommon.h | 2 ++ > fs/ocfs2/dlm/dlmmaster.c | 38 +++------------------------------ > fs/ocfs2/dlm/dlmrecovery.c | 29 +++++++++++++++++++------- > fs/ocfs2/dlm/dlmthread.c | 52 ++++++++++++++++++++++++++++++++++++++++++---- > 4 files changed, 74 insertions(+), 47 deletions(-) > > diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h index 004f2cb..3e3e9ba8 100644 > --- a/fs/ocfs2/dlm/dlmcommon.h > +++ b/fs/ocfs2/dlm/dlmcommon.h > @@ -1004,6 +1004,8 @@ int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data, int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, > u8 nodenum, u8 *real_master); > > +void __dlm_do_purge_lockres(struct dlm_ctxt *dlm, > + struct dlm_lock_resource *res); > > int dlm_dispatch_assert_master(struct dlm_ctxt *dlm, > struct dlm_lock_resource *res, diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index 311404f..1d87e0f 100644 > --- a/fs/ocfs2/dlm/dlmmaster.c > +++ b/fs/ocfs2/dlm/dlmmaster.c > @@ -2425,52 +2425,20 @@ int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data, > mlog(ML_NOTICE, "%s:%.*s: node %u sends deref done " > "but it is already derefed!\n", dlm->name, > res->lockname.len, res->lockname.name, node); > - dlm_lockres_put(res); > ret = 0; > goto done; > } > - > - if (!list_empty(&res->purge)) { > - mlog(0, "%s: Removing res %.*s from purgelist\n", > - dlm->name, res->lockname.len, res->lockname.name); > - list_del_init(&res->purge); > - dlm_lockres_put(res); > - dlm->purge_count--; > - } > - > - if (!__dlm_lockres_unused(res)) { > - mlog(ML_ERROR, "%s: res %.*s in use after deref\n", > - dlm->name, res->lockname.len, res->lockname.name); > - __dlm_print_one_lock_resource(res); > - BUG(); > - } > - > - __dlm_unhash_lockres(dlm, res); > - > - spin_lock(&dlm->track_lock); > - if (!list_empty(&res->tracking)) > - list_del_init(&res->tracking); > - else { > - mlog(ML_ERROR, "%s: Resource %.*s not on the Tracking list\n", > - dlm->name, res->lockname.len, res->lockname.name); > - __dlm_print_one_lock_resource(res); > - } > - spin_unlock(&dlm->track_lock); > - > - /* lockres is not in the hash now. drop the flag and wake up > - * any processes waiting in dlm_get_lock_resource. > - */ > - res->state &= ~DLM_LOCK_RES_DROPPING_REF; > + __dlm_do_purge_lockres(dlm, res); > spin_unlock(&res->spinlock); > wake_up(&res->wq); > > - dlm_lockres_put(res); > - > spin_unlock(&dlm->spinlock); > > ret = 0; > > done: > + if (res) > + dlm_lockres_put(res); > dlm_put(dlm); > return ret; > } > diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index f6b3138..dd5cb8b 100644 > --- a/fs/ocfs2/dlm/dlmrecovery.c > +++ b/fs/ocfs2/dlm/dlmrecovery.c > @@ -2343,6 +2343,7 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) > struct dlm_lock_resource *res; > int i; > struct hlist_head *bucket; > + struct hlist_node *tmp; > struct dlm_lock *lock; > > > @@ -2365,7 +2366,7 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) > */ > for (i = 0; i < DLM_HASH_BUCKETS; i++) { > bucket = dlm_lockres_hash(dlm, i); > - hlist_for_each_entry(res, bucket, hash_node) { > + hlist_for_each_entry_safe(res, tmp, bucket, hash_node) { > /* always prune any $RECOVERY entries for dead nodes, > * otherwise hangs can occur during later recovery */ > if (dlm_is_recovery_lock(res->lockname.name, > @@ -2386,8 +2387,17 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) > break; > } > } > - dlm_lockres_clear_refmap_bit(dlm, res, > - dead_node); > + > + if ((res->owner == dead_node) && > + (res->state & DLM_LOCK_RES_DROPPING_REF)) { > + dlm_lockres_get(res); > + __dlm_do_purge_lockres(dlm, res); > + spin_unlock(&res->spinlock); > + wake_up(&res->wq); > + dlm_lockres_put(res); > + continue; > + } else if (res->owner == dlm->node_num) > + dlm_lockres_clear_refmap_bit(dlm, res, dead_node); > spin_unlock(&res->spinlock); > continue; > } > @@ -2398,14 +2408,17 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) > if (res->state & DLM_LOCK_RES_DROPPING_REF) { > mlog(0, "%s:%.*s: owned by " > "dead node %u, this node was " > - "dropping its ref when it died. " > - "continue, dropping the flag.\n", > + "dropping its ref when master died. " > + "continue, purging the lockres.\n", > dlm->name, res->lockname.len, > res->lockname.name, dead_node); > + dlm_lockres_get(res); > + __dlm_do_purge_lockres(dlm, res); > + spin_unlock(&res->spinlock); > + wake_up(&res->wq); > + dlm_lockres_put(res); > + continue; > } > - res->state &= ~DLM_LOCK_RES_DROPPING_REF; > - dlm_move_lockres_to_recovery_list(dlm, > - res);Here, you just remove above line, thus, no chance for DLM to select lock resources to be recovered, is right?> } 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 ce39722..838a06d 100644 > --- a/fs/ocfs2/dlm/dlmthread.c > +++ b/fs/ocfs2/dlm/dlmthread.c > @@ -160,6 +160,52 @@ void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, > spin_unlock(&dlm->spinlock); > } > > +/* > + * Do the real purge work: > + * unhash the lockres, and > + * clear flag DLM_LOCK_RES_DROPPING_REF. > + * It requires dlm and lockres spinlock to be taken. > + */ > +void __dlm_do_purge_lockres(struct dlm_ctxt *dlm, > + struct dlm_lock_resource *res) > +{ > + assert_spin_locked(&dlm->spinlock); > + assert_spin_locked(&res->spinlock); > + > + if (!list_empty(&res->purge)) { > + mlog(0, "%s: Removing res %.*s from purgelist\n", > + dlm->name, res->lockname.len, res->lockname.name); > + list_del_init(&res->purge); > + dlm_lockres_put(res); > + dlm->purge_count--; > + } > + > + if (!__dlm_lockres_unused(res)) { > + mlog(ML_ERROR, "%s: res %.*s in use after deref\n", > + dlm->name, res->lockname.len, res->lockname.name); > + __dlm_print_one_lock_resource(res); > + BUG(); > + } > + > + __dlm_unhash_lockres(dlm, res); > + > + spin_lock(&dlm->track_lock); > + if (!list_empty(&res->tracking)) > + list_del_init(&res->tracking); > + else { > + mlog(ML_ERROR, "%s: Resource %.*s not on the Tracking list\n", > + dlm->name, res->lockname.len, res->lockname.name); > + __dlm_print_one_lock_resource(res); > + } > + spin_unlock(&dlm->track_lock); > + > + /* > + * lockres is not in the hash now. drop the flag and wake up > + * any processes waiting in dlm_get_lock_resource. > + */ > + res->state &= ~DLM_LOCK_RES_DROPPING_REF; } > + > static void dlm_purge_lockres(struct dlm_ctxt *dlm, > struct dlm_lock_resource *res) > { > @@ -176,10 +222,8 @@ static void dlm_purge_lockres(struct dlm_ctxt *dlm, > > if (!master) { > if (res->state & DLM_LOCK_RES_DROPPING_REF) { > - mlog(ML_NOTICE, "%s: res %.*s already in " > - "DLM_LOCK_RES_DROPPING_REF state\n", > - dlm->name, res->lockname.len, > - res->lockname.name); > + mlog(ML_NOTICE, "%s: res %.*s already in DLM_LOCK_RES_DROPPING_REF state\n", > + dlm->name, res->lockname.len, res->lockname.name); > spin_unlock(&res->spinlock); > return; > } > -- > 1.8.4.3 > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel at oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel------------------------------------------------------------------------------------------------------------------------------------- ???????????????????????????????????????? ???????????????????????????????????????? ???????????????????????????????????????? ??? 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piaojun
2017-Jan-06 02:07 UTC
[Ocfs2-devel] [PATCH v2 3/3] ocfs2/dlm: continue to purge recovery lockres when recovery master goes down
On 2017/1/5 15:44, Gechangwei wrote:> On 2017/1/5 15:28, gechangwei 12382 (Cloud) wrote: > > Hi Jun, > I suppose that a defect hid your patch. > > >> We found a dlm-blocked situation caused by continuous breakdown of recovery masters described below. To solve this problem, we should purge recovery lock once detecting recovery master goes down. >> >> N3 N2 N1(reco master) >> go down >> pick up recovery lock and >> begin recoverying for N2 >> >> go down >> >> pick up recovery >> lock failed, then >> purge it: >> dlm_purge_lockres >> ->DROPPING_REF is set >> >> send deref to N1 failed, >> recovery lock is not purged >> >> find N1 go down, begin >> recoverying for N1, but >> blocked in dlm_do_recovery >> as DROPPING_REF is set: >> dlm_do_recovery >> ->dlm_pick_recovery_master >> ->dlmlock >> ->dlm_get_lock_resource >> ->__dlm_wait_on_lockres_flags(tmpres, >> DLM_LOCK_RES_DROPPING_REF); >> >> Fixes: 8c0343968163 ("ocfs2/dlm: clear DROPPING_REF flag when the master goes down") >> >> Signed-off-by: Jun Piao <piaojun at huawei.com> >> Reviewed-by: Joseph Qi <joseph.qi at huawei.com> >> Reviewed-by: Jiufei Xue <xuejiufei at huawei.com> >> --- >> fs/ocfs2/dlm/dlmcommon.h | 2 ++ >> fs/ocfs2/dlm/dlmmaster.c | 38 +++------------------------------ >> fs/ocfs2/dlm/dlmrecovery.c | 29 +++++++++++++++++++------- >> fs/ocfs2/dlm/dlmthread.c | 52 ++++++++++++++++++++++++++++++++++++++++++---- >> 4 files changed, 74 insertions(+), 47 deletions(-) >> >> diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h index 004f2cb..3e3e9ba8 100644 >> --- a/fs/ocfs2/dlm/dlmcommon.h >> +++ b/fs/ocfs2/dlm/dlmcommon.h >> @@ -1004,6 +1004,8 @@ int dlm_finalize_reco_handler(struct o2net_msg *msg, u32 len, void *data, int dlm_do_master_requery(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, >> u8 nodenum, u8 *real_master); >> >> +void __dlm_do_purge_lockres(struct dlm_ctxt *dlm, >> + struct dlm_lock_resource *res); >> >> int dlm_dispatch_assert_master(struct dlm_ctxt *dlm, >> struct dlm_lock_resource *res, diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index 311404f..1d87e0f 100644 >> --- a/fs/ocfs2/dlm/dlmmaster.c >> +++ b/fs/ocfs2/dlm/dlmmaster.c >> @@ -2425,52 +2425,20 @@ int dlm_deref_lockres_done_handler(struct o2net_msg *msg, u32 len, void *data, >> mlog(ML_NOTICE, "%s:%.*s: node %u sends deref done " >> "but it is already derefed!\n", dlm->name, >> res->lockname.len, res->lockname.name, node); >> - dlm_lockres_put(res); >> ret = 0; >> goto done; >> } >> - >> - if (!list_empty(&res->purge)) { >> - mlog(0, "%s: Removing res %.*s from purgelist\n", >> - dlm->name, res->lockname.len, res->lockname.name); >> - list_del_init(&res->purge); >> - dlm_lockres_put(res); >> - dlm->purge_count--; >> - } >> - >> - if (!__dlm_lockres_unused(res)) { >> - mlog(ML_ERROR, "%s: res %.*s in use after deref\n", >> - dlm->name, res->lockname.len, res->lockname.name); >> - __dlm_print_one_lock_resource(res); >> - BUG(); >> - } >> - >> - __dlm_unhash_lockres(dlm, res); >> - >> - spin_lock(&dlm->track_lock); >> - if (!list_empty(&res->tracking)) >> - list_del_init(&res->tracking); >> - else { >> - mlog(ML_ERROR, "%s: Resource %.*s not on the Tracking list\n", >> - dlm->name, res->lockname.len, res->lockname.name); >> - __dlm_print_one_lock_resource(res); >> - } >> - spin_unlock(&dlm->track_lock); >> - >> - /* lockres is not in the hash now. drop the flag and wake up >> - * any processes waiting in dlm_get_lock_resource. >> - */ >> - res->state &= ~DLM_LOCK_RES_DROPPING_REF; >> + __dlm_do_purge_lockres(dlm, res); >> spin_unlock(&res->spinlock); >> wake_up(&res->wq); >> >> - dlm_lockres_put(res); >> - >> spin_unlock(&dlm->spinlock); >> >> ret = 0; >> >> done: >> + if (res) >> + dlm_lockres_put(res); >> dlm_put(dlm); >> return ret; >> } >> diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index f6b3138..dd5cb8b 100644 >> --- a/fs/ocfs2/dlm/dlmrecovery.c >> +++ b/fs/ocfs2/dlm/dlmrecovery.c >> @@ -2343,6 +2343,7 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) >> struct dlm_lock_resource *res; >> int i; >> struct hlist_head *bucket; >> + struct hlist_node *tmp; >> struct dlm_lock *lock; >> >> >> @@ -2365,7 +2366,7 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) >> */ >> for (i = 0; i < DLM_HASH_BUCKETS; i++) { >> bucket = dlm_lockres_hash(dlm, i); >> - hlist_for_each_entry(res, bucket, hash_node) { >> + hlist_for_each_entry_safe(res, tmp, bucket, hash_node) { >> /* always prune any $RECOVERY entries for dead nodes, >> * otherwise hangs can occur during later recovery */ >> if (dlm_is_recovery_lock(res->lockname.name, >> @@ -2386,8 +2387,17 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) >> break; >> } >> } >> - dlm_lockres_clear_refmap_bit(dlm, res, >> - dead_node); >> + >> + if ((res->owner == dead_node) && >> + (res->state & DLM_LOCK_RES_DROPPING_REF)) { >> + dlm_lockres_get(res); >> + __dlm_do_purge_lockres(dlm, res); >> + spin_unlock(&res->spinlock); >> + wake_up(&res->wq); >> + dlm_lockres_put(res); >> + continue; >> + } else if (res->owner == dlm->node_num) >> + dlm_lockres_clear_refmap_bit(dlm, res, dead_node); >> spin_unlock(&res->spinlock); >> continue; >> } >> @@ -2398,14 +2408,17 @@ static void dlm_do_local_recovery_cleanup(struct dlm_ctxt *dlm, u8 dead_node) >> if (res->state & DLM_LOCK_RES_DROPPING_REF) { >> mlog(0, "%s:%.*s: owned by " >> "dead node %u, this node was " >> - "dropping its ref when it died. " >> - "continue, dropping the flag.\n", >> + "dropping its ref when master died. " >> + "continue, purging the lockres.\n", >> dlm->name, res->lockname.len, >> res->lockname.name, dead_node); >> + dlm_lockres_get(res); >> + __dlm_do_purge_lockres(dlm, res); >> + spin_unlock(&res->spinlock); >> + wake_up(&res->wq); >> + dlm_lockres_put(res); >> + continue; >> } >> - res->state &= ~DLM_LOCK_RES_DROPPING_REF; >> - dlm_move_lockres_to_recovery_list(dlm, >> - res); > > Here, you just remove above line, thus, no chance for DLM to select lock > resources to be recovered, is right? > > >Here we purge lockres directly instead of moving to recovery list when DLM_LOCK_RES_DROPPING_REF is set in case of deadlock. Thanks, Jun>> } 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 ce39722..838a06d 100644 >> --- a/fs/ocfs2/dlm/dlmthread.c >> +++ b/fs/ocfs2/dlm/dlmthread.c >> @@ -160,6 +160,52 @@ void dlm_lockres_calc_usage(struct dlm_ctxt *dlm, >> spin_unlock(&dlm->spinlock); >> } >> >> +/* >> + * Do the real purge work: >> + * unhash the lockres, and >> + * clear flag DLM_LOCK_RES_DROPPING_REF. >> + * It requires dlm and lockres spinlock to be taken. >> + */ >> +void __dlm_do_purge_lockres(struct dlm_ctxt *dlm, >> + struct dlm_lock_resource *res) >> +{ >> + assert_spin_locked(&dlm->spinlock); >> + assert_spin_locked(&res->spinlock); >> + >> + if (!list_empty(&res->purge)) { >> + mlog(0, "%s: Removing res %.*s from purgelist\n", >> + dlm->name, res->lockname.len, res->lockname.name); >> + list_del_init(&res->purge); >> + dlm_lockres_put(res); >> + dlm->purge_count--; >> + } >> + >> + if (!__dlm_lockres_unused(res)) { >> + mlog(ML_ERROR, "%s: res %.*s in use after deref\n", >> + dlm->name, res->lockname.len, res->lockname.name); >> + __dlm_print_one_lock_resource(res); >> + BUG(); >> + } >> + >> + __dlm_unhash_lockres(dlm, res); >> + >> + spin_lock(&dlm->track_lock); >> + if (!list_empty(&res->tracking)) >> + list_del_init(&res->tracking); >> + else { >> + mlog(ML_ERROR, "%s: Resource %.*s not on the Tracking list\n", >> + dlm->name, res->lockname.len, res->lockname.name); >> + __dlm_print_one_lock_resource(res); >> + } >> + spin_unlock(&dlm->track_lock); >> + >> + /* >> + * lockres is not in the hash now. drop the flag and wake up >> + * any processes waiting in dlm_get_lock_resource. >> + */ >> + res->state &= ~DLM_LOCK_RES_DROPPING_REF; } >> + >> static void dlm_purge_lockres(struct dlm_ctxt *dlm, >> struct dlm_lock_resource *res) >> { >> @@ -176,10 +222,8 @@ static void dlm_purge_lockres(struct dlm_ctxt *dlm, >> >> if (!master) { >> if (res->state & DLM_LOCK_RES_DROPPING_REF) { >> - mlog(ML_NOTICE, "%s: res %.*s already in " >> - "DLM_LOCK_RES_DROPPING_REF state\n", >> - dlm->name, res->lockname.len, >> - res->lockname.name); >> + mlog(ML_NOTICE, "%s: res %.*s already in DLM_LOCK_RES_DROPPING_REF state\n", >> + dlm->name, res->lockname.len, res->lockname.name); >> spin_unlock(&res->spinlock); >> return; >> } >> -- >> 1.8.4.3 >> >> >> _______________________________________________ >> Ocfs2-devel mailing list >> Ocfs2-devel at oss.oracle.com >> https://oss.oracle.com/mailman/listinfo/ocfs2-devel > > > ------------------------------------------------------------------------------------------------------------------------------------- > ???????????????????????????????????????? > ???????????????????????????????????????? > ???????????????????????????????????????? > ??? > This e-mail and its attachments contain confidential information from H3C, which is > intended only for the person or entity whose address is listed above. Any use of the > information contained herein in any way (including, but not limited to, total or partial > disclosure, reproduction, or dissemination) by persons other than the intended > recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender > by phone or email immediately and delete it! >