We've had some cases of hung umounts in teuthology testing. It looks like client is waiting for cap flushes to complete, but they aren't. Add a field to the inode to track the highest cap flush tid seen for that inode. Also, add a backpointer to the inode to the ceph_cap_flush struct. Change wait_caps_flush to wait 60s, and then dump info about the condition of the list. Reported-by: Patrick Donnelly <pdonnell@xxxxxxxxxx> URL: https://tracker.ceph.com/issues/51279 Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/ceph/caps.c | 5 +++++ fs/ceph/inode.c | 1 + fs/ceph/mds_client.c | 30 ++++++++++++++++++++++++++++-- fs/ceph/super.h | 2 ++ 4 files changed, 36 insertions(+), 2 deletions(-) I revised this patch a bit to gather some more info. Again, I'll put this into the testing kernel with a [DO NOT MERGE] tag. diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 7ae83d06d48c..6c24b2eb865c 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -1829,6 +1829,7 @@ static u64 __mark_caps_flushing(struct inode *inode, swap(cf, ci->i_prealloc_cap_flush); cf->caps = flushing; cf->wake = wake; + cf->ci = ci; spin_lock(&mdsc->cap_dirty_lock); list_del_init(&ci->i_dirty_item); @@ -3588,6 +3589,10 @@ static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid, bool wake_ci = false; bool wake_mdsc = false; + /* track latest cap flush ack seen for this inode */ + if (flush_tid > ci->i_last_cap_flush_ack) + ci->i_last_cap_flush_ack = flush_tid; + list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) { /* Is this the one that was flushed? */ if (cf->tid == flush_tid) diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 1bd2cc015913..84e4f112fc45 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -499,6 +499,7 @@ struct inode *ceph_alloc_inode(struct super_block *sb) INIT_LIST_HEAD(&ci->i_cap_snaps); ci->i_head_snapc = NULL; ci->i_snap_caps = 0; + ci->i_last_cap_flush_ack = 0; ci->i_last_rd = ci->i_last_wr = jiffies - 3600 * HZ; for (i = 0; i < CEPH_FILE_MODE_BITS; i++) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index c3fa0c0e4f6c..c43091a30ba8 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -2064,6 +2064,23 @@ static int check_caps_flush(struct ceph_mds_client *mdsc, return ret; } +static void dump_cap_flushes(struct ceph_mds_client *mdsc, u64 want_tid) +{ + struct ceph_cap_flush *cf; + + pr_info("%s: still waiting for cap flushes through %llu\n:\n", + __func__, want_tid); + spin_lock(&mdsc->cap_dirty_lock); + list_for_each_entry(cf, &mdsc->cap_flush_list, g_list) { + if (cf->tid > want_tid) + break; + pr_info("0x%llx %s %llu %llu %d\n", cf->ci->i_vino.ino, + ceph_cap_string(cf->caps), cf->tid, + cf->ci->i_last_cap_flush_ack, cf->wake); + } + spin_unlock(&mdsc->cap_dirty_lock); +} + /* * flush all dirty inode data to disk. * @@ -2072,10 +2089,19 @@ static int check_caps_flush(struct ceph_mds_client *mdsc, static void wait_caps_flush(struct ceph_mds_client *mdsc, u64 want_flush_tid) { + long ret; + dout("check_caps_flush want %llu\n", want_flush_tid); - wait_event(mdsc->cap_flushing_wq, - check_caps_flush(mdsc, want_flush_tid)); + do { + ret = wait_event_timeout(mdsc->cap_flushing_wq, + check_caps_flush(mdsc, want_flush_tid), 60 * HZ); + if (ret == 0) + dump_cap_flushes(mdsc, want_flush_tid); + else if (ret == 1) + pr_info("%s: condition evaluated to true after timeout!\n", + __func__); + } while (ret == 0); dout("check_caps_flush ok, flushed thru %llu\n", want_flush_tid); } diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 07eb542efa1d..d51d42a00f33 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -189,6 +189,7 @@ struct ceph_cap_flush { bool wake; /* wake up flush waiters when finish ? */ struct list_head g_list; // global struct list_head i_list; // per inode + struct ceph_inode_info *ci; }; /* @@ -388,6 +389,7 @@ struct ceph_inode_info { struct ceph_snap_context *i_head_snapc; /* set if wr_buffer_head > 0 or dirty|flushing caps */ unsigned i_snap_caps; /* cap bits for snapped files */ + u64 i_last_cap_flush_ack; /* latest cap flush_ack tid for this inode */ unsigned long i_last_rd; unsigned long i_last_wr; -- 2.31.1
