| Message ID | 1440536130-29622-1-git-send-email-tariq.x.saeed@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Tariq, As I know, global bitmap inode mutex will be held when doing allocation. So how can it happen that EX and PR requests come concurrently int the same node? Thanks, Joseph On 2015/8/26 4:55, Tariq Saeed wrote: > Orabug: 20933419 > > NFS on a 2 node ocfs2 cluster each node exporting dir. The lock causing > the hang is the global bit map inode lock. Node 1 is master, has > the lock granted in PR mode; Node 2 is in the converting list (PR -> > EX). There are no holders of the lock on the master node so it should > downconvert to NL and grant EX to node 2 but that does not happen. > BLOCKED + QUEUED in lock res are set and it is on osb blocked list. > Threads are waiting in __ocfs2_cluster_lock on BLOCKED. One thread wants > EX, rest want PR. So it is as though the downconvert thread needs to be > kicked to complete the conv. > > The hang is caused by an EX req coming into __ocfs2_cluster_lock on > the heels of a PR req after it sets BUSY (drops l_lock, releasing EX > thread), forcing the incoming EX to wait on BUSY without doing anything. > PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> > PR, queues ast. > > At this time, upconvert (PR ->EX) arrives from node 2, finds conflict with > node 1 lock in PR, so the lock res is put on dlm thread's dirty listt. > > After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till > awoken by ast. > > Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, > in that order. dlm_shuffle_lists ques a bast on behalf of node 2 > (which will be run by dlm_thread right after the ast). ast does its > part, sets UPCONVERT_FINISHING, clears BUSY and wakes its waiters. Next, > dlm_thread runs bast. It sets BLOCKED and kicks dc thread. dc thread > runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing > anything and reques. > > Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead > of PR, it wakes up first, finds BLOCKED set and skips doing anything > but clearing UPCONVERT_FINISHING (which was actually "meant" for the > PR thread), and this time waits on BLOCKED. Next, the PR thread comes > out of wait but since UPCONVERT_FINISHING is not set, it skips updating > the l_ro_holders and goes straight to wait on BLOCKED. So there, we > have a hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock > res in osb blocked list. Only when dc thread is awoken, it will run > ocfs2_unblock_lock and things will unhang. > > One way to fix this is to wake the dc thread on the flag after clearing > UPCONVERT_FINISHING > > Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com> > Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> > --- > fs/ocfs2/dlmglue.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c > index 8b23aa2..313c816 100644 > --- a/fs/ocfs2/dlmglue.c > +++ b/fs/ocfs2/dlmglue.c > @@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb, > unsigned int gen; > int noqueue_attempted = 0; > int dlm_locked = 0; > + int kick_dc = 0; > > if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) { > mlog_errno(-EINVAL); > @@ -1524,7 +1525,12 @@ update_holders: > unlock: > lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING); > > + /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */ > + kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED); > + > spin_unlock_irqrestore(&lockres->l_lock, flags); > + if (kick_dc) > + ocfs2_wake_downconvert_thread(osb); > out: > /* > * This is helping work around a lock inversion between the page lock >
Hi Joseph, Many threads doing this: PID: 6352 TASK: ffff8801a0a30100 CPU: 3 COMMAND: "nfsd"//blocked on same lock as 6323 , gen 0 #0 [ffff8801a0a338d0] __schedule at ffffffff8150a954 #1 [ffff8801a0a33978] schedule at ffffffff8150b0ef #2 [ffff8801a0a33988] schedule_timeout at ffffffff8150b59d #3 [ffff8801a0a33a38] wait_for_common at ffffffff8150af7a #4 [ffff8801a0a33ad8] wait_for_completion at ffffffff8150b0ad #5 [ffff8801a0a33ae8] __ocfs2_cluster_lock at ffffffffa03febd8 [ocfs2] #6 [ffff8801a0a33c48] ocfs2_inode_lock_full_nested at ffffffffa0404086 [ocfs2] #7 [ffff8801a0a33cc8] ocfs2_statfs at ffffffffa045462e [ocfs2] <<<< does not take mutex of global bit map taken. #8 [ffff8801a0a33d28] statfs_by_dentry at ffffffff81199b29 #9 [ffff8801a0a33d48] vfs_statfs at ffffffff81199b6b #10 [ffff8801a0a33d68] nfsd_statfs at ffffffffa036bd73 [nfsd] #11 [ffff8801a0a33da8] nfsd3_proc_fsstat at ffffffffa0374f0d [nfsd] #12 [ffff8801a0a33dd8] nfsd_dispatch at ffffffffa036743e [nfsd] #13 [ffff8801a0a33e18] svc_process_common at ffffffffa0278324 [sunrpc] #14 [ffff8801a0a33e98] svc_process at ffffffffa0278970 [sunrpc] #15 [ffff8801a0a33eb8] nfsd at ffffffffa0367b92 [nfsd] #16 [ffff8801a0a33ee8] kthread at ffffffff81090ec6 #17 [ffff8801a0a33f48] kernel_thread_helper at ffffffff815166c4 and the one doing alloc w PID: 6323 TASK: ffff8801a7054640 CPU: 0 COMMAND: "nfsd" #0 [ffff8801a7056f10] __schedule at ffffffff8150a954 #1 [ffff8801a7056fb8] schedule at ffffffff8150b0ef #2 [ffff8801a7056fc8] schedule_timeout at ffffffff8150b59d #3 [ffff8801a7057078] wait_for_common at ffffffff8150af7a #4 [ffff8801a7057118] wait_for_completion at ffffffff8150b0ad #5 [ffff8801a7057128] __ocfs2_cluster_lock at ffffffffa03febd8 [ocfs2] #6 [ffff8801a7057288] ocfs2_inode_lock_full_nested at ffffffffa0404086 [ocfs2] #7 [ffff8801a7057308] ocfs2_reserve_suballoc_bits at ffffffffa043f199 [ocfs2] <<<< takes global bit map mutex #8 [ffff8801a7057388] ocfs2_reserve_cluster_bitmap_bits at ffffffffa043f5f5 [ocfs2] #9 [ffff8801a70573b8] ocfs2_local_alloc_reserve_for_window at ffffffffa04198a4 [ocfs2] #10 [ffff8801a7057418] ocfs2_local_alloc_slide_window at ffffffffa041b5a0 [ocfs2] #11 [ffff8801a7057498] ocfs2_reserve_local_alloc_bits at ffffffffa041bc67 [ocfs2] #12 [ffff8801a70574f8] ocfs2_reserve_clusters_with_limit at ffffffffa043e8c5 [ocfs2] #13 [ffff8801a7057548] ocfs2_reserve_clusters at ffffffffa043f7f8 [ocfs2] #14 [ffff8801a7057558] ocfs2_lock_allocators at ffffffffa044021e [ocfs2] #15 [ffff8801a70575b8] ocfs2_write_begin_nolock at ffffffffa03ed713 [ocfs2] #16 [ffff8801a7057758] ocfs2_write_begin at ffffffffa03ee0c6 [ocfs2] #17 [ffff8801a70577e8] generic_perform_write at ffffffff8110ffc3 #18 [ffff8801a7057888] generic_file_buffered_write_iter at ffffffff811100eb #19 [ffff8801a70578b8] ocfs2_file_write_iter at ffffffffa040a837 [ocfs2] #20 [ffff8801a70579c8] ocfs2_file_aio_write at ffffffffa040af28 [ocfs2] #21 [ffff8801a7057a38] do_sync_readv_writev at ffffffff8116cf7b #22 [ffff8801a7057b48] do_readv_writev at ffffffff8116ddf4 #23 [ffff8801a7057c28] vfs_writev at ffffffff8116df46 #24 [ffff8801a7057c38] nfsd_vfs_write at ffffffffa036c7f3 [nfsd] #25 [ffff8801a7057d08] nfsd_write at ffffffffa036de77 [nfsd] #26 [ffff8801a7057d68] nfsd3_proc_write at ffffffffa03762ff [nfsd] #27 [ffff8801a7057dd8] nfsd_dispatch at ffffffffa036743e [nfsd] #28 [ffff8801a7057e18] svc_process_common at ffffffffa0278324 [sunrpc] #29 [ffff8801a7057e98] svc_process at ffffffffa0278970 [sunrpc] #30 [ffff8801a7057eb8] nfsd at ffffffffa0367b92 [nfsd] #31 [ffff8801a7057ee8] kthread at ffffffff81090ec6 #32 [ffff8801a7057f48] kernel_thread_helper at ffffffff815166c4 Thanks -Tariq On 12/23/2015 01:31 AM, Joseph Qi wrote: > Hi Tariq, > As I know, global bitmap inode mutex will be held when doing allocation. > So how can it happen that EX and PR requests come concurrently int the > same node? > > Thanks, > Joseph > > On 2015/8/26 4:55, Tariq Saeed wrote: >> Orabug: 20933419 >> >> NFS on a 2 node ocfs2 cluster each node exporting dir. The lock causing >> the hang is the global bit map inode lock. Node 1 is master, has >> the lock granted in PR mode; Node 2 is in the converting list (PR -> >> EX). There are no holders of the lock on the master node so it should >> downconvert to NL and grant EX to node 2 but that does not happen. >> BLOCKED + QUEUED in lock res are set and it is on osb blocked list. >> Threads are waiting in __ocfs2_cluster_lock on BLOCKED. One thread wants >> EX, rest want PR. So it is as though the downconvert thread needs to be >> kicked to complete the conv. >> >> The hang is caused by an EX req coming into __ocfs2_cluster_lock on >> the heels of a PR req after it sets BUSY (drops l_lock, releasing EX >> thread), forcing the incoming EX to wait on BUSY without doing anything. >> PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> >> PR, queues ast. >> >> At this time, upconvert (PR ->EX) arrives from node 2, finds conflict with >> node 1 lock in PR, so the lock res is put on dlm thread's dirty listt. >> >> After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till >> awoken by ast. >> >> Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, >> in that order. dlm_shuffle_lists ques a bast on behalf of node 2 >> (which will be run by dlm_thread right after the ast). ast does its >> part, sets UPCONVERT_FINISHING, clears BUSY and wakes its waiters. Next, >> dlm_thread runs bast. It sets BLOCKED and kicks dc thread. dc thread >> runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing >> anything and reques. >> >> Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead >> of PR, it wakes up first, finds BLOCKED set and skips doing anything >> but clearing UPCONVERT_FINISHING (which was actually "meant" for the >> PR thread), and this time waits on BLOCKED. Next, the PR thread comes >> out of wait but since UPCONVERT_FINISHING is not set, it skips updating >> the l_ro_holders and goes straight to wait on BLOCKED. So there, we >> have a hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock >> res in osb blocked list. Only when dc thread is awoken, it will run >> ocfs2_unblock_lock and things will unhang. >> >> One way to fix this is to wake the dc thread on the flag after clearing >> UPCONVERT_FINISHING >> >> Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com> >> Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com> >> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> >> --- >> fs/ocfs2/dlmglue.c | 6 ++++++ >> 1 files changed, 6 insertions(+), 0 deletions(-) >> >> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c >> index 8b23aa2..313c816 100644 >> --- a/fs/ocfs2/dlmglue.c >> +++ b/fs/ocfs2/dlmglue.c >> @@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb, >> unsigned int gen; >> int noqueue_attempted = 0; >> int dlm_locked = 0; >> + int kick_dc = 0; >> >> if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) { >> mlog_errno(-EINVAL); >> @@ -1524,7 +1525,12 @@ update_holders: >> unlock: >> lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING); >> >> + /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */ >> + kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED); >> + >> spin_unlock_irqrestore(&lockres->l_lock, flags); >> + if (kick_dc) >> + ocfs2_wake_downconvert_thread(osb); >> out: >> /* >> * This is helping work around a lock inversion between the page lock >> >
IC, the PR request is coming from statfs which doesn't require global bitmap i_mutex. So it looks good to me. Reviewed-by: Joseph Qi <joseph.qi@huawei.com> On 2015/12/24 3:20, Tariq Saeed wrote: > Hi Joseph, > Many threads doing this: > PID: 6352 TASK: ffff8801a0a30100 CPU: 3 COMMAND: "nfsd"//blocked on same lock as 6323 , gen 0 > #0 [ffff8801a0a338d0] __schedule at ffffffff8150a954 > #1 [ffff8801a0a33978] schedule at ffffffff8150b0ef > #2 [ffff8801a0a33988] schedule_timeout at ffffffff8150b59d > #3 [ffff8801a0a33a38] wait_for_common at ffffffff8150af7a > #4 [ffff8801a0a33ad8] wait_for_completion at ffffffff8150b0ad > #5 [ffff8801a0a33ae8] __ocfs2_cluster_lock at ffffffffa03febd8 [ocfs2] > #6 [ffff8801a0a33c48] ocfs2_inode_lock_full_nested at ffffffffa0404086 [ocfs2] > #7 [ffff8801a0a33cc8] ocfs2_statfs at ffffffffa045462e [ocfs2] <<<< does not take mutex of global bit map taken. > #8 [ffff8801a0a33d28] statfs_by_dentry at ffffffff81199b29 > #9 [ffff8801a0a33d48] vfs_statfs at ffffffff81199b6b > #10 [ffff8801a0a33d68] nfsd_statfs at ffffffffa036bd73 [nfsd] > #11 [ffff8801a0a33da8] nfsd3_proc_fsstat at ffffffffa0374f0d [nfsd] > #12 [ffff8801a0a33dd8] nfsd_dispatch at ffffffffa036743e [nfsd] > #13 [ffff8801a0a33e18] svc_process_common at ffffffffa0278324 [sunrpc] > #14 [ffff8801a0a33e98] svc_process at ffffffffa0278970 [sunrpc] > #15 [ffff8801a0a33eb8] nfsd at ffffffffa0367b92 [nfsd] > #16 [ffff8801a0a33ee8] kthread at ffffffff81090ec6 > #17 [ffff8801a0a33f48] kernel_thread_helper at ffffffff815166c4 > > and the one doing alloc w > > PID: 6323 TASK: ffff8801a7054640 CPU: 0 COMMAND: "nfsd" > #0 [ffff8801a7056f10] __schedule at ffffffff8150a954 > #1 [ffff8801a7056fb8] schedule at ffffffff8150b0ef > #2 [ffff8801a7056fc8] schedule_timeout at ffffffff8150b59d > #3 [ffff8801a7057078] wait_for_common at ffffffff8150af7a > #4 [ffff8801a7057118] wait_for_completion at ffffffff8150b0ad > #5 [ffff8801a7057128] __ocfs2_cluster_lock at ffffffffa03febd8 [ocfs2] > #6 [ffff8801a7057288] ocfs2_inode_lock_full_nested at ffffffffa0404086 [ocfs2] > #7 [ffff8801a7057308] ocfs2_reserve_suballoc_bits at ffffffffa043f199 [ocfs2] <<<< takes global bit map mutex > #8 [ffff8801a7057388] ocfs2_reserve_cluster_bitmap_bits at ffffffffa043f5f5 [ocfs2] > #9 [ffff8801a70573b8] ocfs2_local_alloc_reserve_for_window at ffffffffa04198a4 [ocfs2] > #10 [ffff8801a7057418] ocfs2_local_alloc_slide_window at ffffffffa041b5a0 [ocfs2] > #11 [ffff8801a7057498] ocfs2_reserve_local_alloc_bits at ffffffffa041bc67 [ocfs2] > #12 [ffff8801a70574f8] ocfs2_reserve_clusters_with_limit at ffffffffa043e8c5 [ocfs2] > #13 [ffff8801a7057548] ocfs2_reserve_clusters at ffffffffa043f7f8 [ocfs2] > #14 [ffff8801a7057558] ocfs2_lock_allocators at ffffffffa044021e [ocfs2] > #15 [ffff8801a70575b8] ocfs2_write_begin_nolock at ffffffffa03ed713 [ocfs2] > #16 [ffff8801a7057758] ocfs2_write_begin at ffffffffa03ee0c6 [ocfs2] > #17 [ffff8801a70577e8] generic_perform_write at ffffffff8110ffc3 > #18 [ffff8801a7057888] generic_file_buffered_write_iter at ffffffff811100eb > #19 [ffff8801a70578b8] ocfs2_file_write_iter at ffffffffa040a837 [ocfs2] > #20 [ffff8801a70579c8] ocfs2_file_aio_write at ffffffffa040af28 [ocfs2] > #21 [ffff8801a7057a38] do_sync_readv_writev at ffffffff8116cf7b > #22 [ffff8801a7057b48] do_readv_writev at ffffffff8116ddf4 > #23 [ffff8801a7057c28] vfs_writev at ffffffff8116df46 > #24 [ffff8801a7057c38] nfsd_vfs_write at ffffffffa036c7f3 [nfsd] > #25 [ffff8801a7057d08] nfsd_write at ffffffffa036de77 [nfsd] > #26 [ffff8801a7057d68] nfsd3_proc_write at ffffffffa03762ff [nfsd] > #27 [ffff8801a7057dd8] nfsd_dispatch at ffffffffa036743e [nfsd] > #28 [ffff8801a7057e18] svc_process_common at ffffffffa0278324 [sunrpc] > #29 [ffff8801a7057e98] svc_process at ffffffffa0278970 [sunrpc] > #30 [ffff8801a7057eb8] nfsd at ffffffffa0367b92 [nfsd] > #31 [ffff8801a7057ee8] kthread at ffffffff81090ec6 > #32 [ffff8801a7057f48] kernel_thread_helper at ffffffff815166c4 > > Thanks > -Tariq > > On 12/23/2015 01:31 AM, Joseph Qi wrote: >> Hi Tariq, >> As I know, global bitmap inode mutex will be held when doing allocation. >> So how can it happen that EX and PR requests come concurrently int the >> same node? >> >> Thanks, >> Joseph >> >> On 2015/8/26 4:55, Tariq Saeed wrote: >>> Orabug: 20933419 >>> >>> NFS on a 2 node ocfs2 cluster each node exporting dir. The lock causing >>> the hang is the global bit map inode lock. Node 1 is master, has >>> the lock granted in PR mode; Node 2 is in the converting list (PR -> >>> EX). There are no holders of the lock on the master node so it should >>> downconvert to NL and grant EX to node 2 but that does not happen. >>> BLOCKED + QUEUED in lock res are set and it is on osb blocked list. >>> Threads are waiting in __ocfs2_cluster_lock on BLOCKED. One thread wants >>> EX, rest want PR. So it is as though the downconvert thread needs to be >>> kicked to complete the conv. >>> >>> The hang is caused by an EX req coming into __ocfs2_cluster_lock on >>> the heels of a PR req after it sets BUSY (drops l_lock, releasing EX >>> thread), forcing the incoming EX to wait on BUSY without doing anything. >>> PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> >>> PR, queues ast. >>> >>> At this time, upconvert (PR ->EX) arrives from node 2, finds conflict with >>> node 1 lock in PR, so the lock res is put on dlm thread's dirty listt. >>> >>> After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till >>> awoken by ast. >>> >>> Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, >>> in that order. dlm_shuffle_lists ques a bast on behalf of node 2 >>> (which will be run by dlm_thread right after the ast). ast does its >>> part, sets UPCONVERT_FINISHING, clears BUSY and wakes its waiters. Next, >>> dlm_thread runs bast. It sets BLOCKED and kicks dc thread. dc thread >>> runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing >>> anything and reques. >>> >>> Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead >>> of PR, it wakes up first, finds BLOCKED set and skips doing anything >>> but clearing UPCONVERT_FINISHING (which was actually "meant" for the >>> PR thread), and this time waits on BLOCKED. Next, the PR thread comes >>> out of wait but since UPCONVERT_FINISHING is not set, it skips updating >>> the l_ro_holders and goes straight to wait on BLOCKED. So there, we >>> have a hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock >>> res in osb blocked list. Only when dc thread is awoken, it will run >>> ocfs2_unblock_lock and things will unhang. >>> >>> One way to fix this is to wake the dc thread on the flag after clearing >>> UPCONVERT_FINISHING >>> >>> Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com> >>> Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com> >>> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> >>> --- >>> fs/ocfs2/dlmglue.c | 6 ++++++ >>> 1 files changed, 6 insertions(+), 0 deletions(-) >>> >>> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c >>> index 8b23aa2..313c816 100644 >>> --- a/fs/ocfs2/dlmglue.c >>> +++ b/fs/ocfs2/dlmglue.c >>> @@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb, >>> unsigned int gen; >>> int noqueue_attempted = 0; >>> int dlm_locked = 0; >>> + int kick_dc = 0; >>> if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) { >>> mlog_errno(-EINVAL); >>> @@ -1524,7 +1525,12 @@ update_holders: >>> unlock: >>> lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING); >>> + /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */ >>> + kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED); >>> + >>> spin_unlock_irqrestore(&lockres->l_lock, flags); >>> + if (kick_dc) >>> + ocfs2_wake_downconvert_thread(osb); >>> out: >>> /* >>> * This is helping work around a lock inversion between the page lock >>> >> > > > . >
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c index 8b23aa2..313c816 100644 --- a/fs/ocfs2/dlmglue.c +++ b/fs/ocfs2/dlmglue.c @@ -1390,6 +1390,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb, unsigned int gen; int noqueue_attempted = 0; int dlm_locked = 0; + int kick_dc = 0; if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) { mlog_errno(-EINVAL); @@ -1524,7 +1525,12 @@ update_holders: unlock: lockres_clear_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING); + /* ocfs2_unblock_lock reques on seeing OCFS2_LOCK_UPCONVERT_FINISHING */ + kick_dc = (lockres->l_flags & OCFS2_LOCK_BLOCKED); + spin_unlock_irqrestore(&lockres->l_lock, flags); + if (kick_dc) + ocfs2_wake_downconvert_thread(osb); out: /* * This is helping work around a lock inversion between the page lock