I've noticed an intermittent hang waiting for caps in some testing. What I see is that the client will try to get caps for an operation (e.g. a read), and ends up waiting on the waitqueue forever. The caps debugfs file however shows that the caps it's waiting on have already been granted. The current grant handling code will wake the waitqueue when it sees that there are newly-granted caps in the issued set. On an import however, we'll end up adding a new cap first, which fools the logic into thinking that nothing has changed. A later hack in the code works around this, but only for auth caps. Ensure we wake the waiters whenever we get an IMPORT that grants new caps for the inode. URL: https://tracker.ceph.com/issues/54044 Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/ceph/caps.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) I'm still testing this patch, but I think this may be the cause of some mysterious hangs I've hit in testing. diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index e668cdb9c99e..06b65a68e920 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -3541,21 +3541,22 @@ static void handle_cap_grant(struct inode *inode, fill_inline = true; } - if (ci->i_auth_cap == cap && - le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) { + if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) { if (newcaps & ~extra_info->issued) wake = true; - if (ci->i_requested_max_size > max_size || - !(le32_to_cpu(grant->wanted) & CEPH_CAP_ANY_FILE_WR)) { - /* re-request max_size if necessary */ - ci->i_requested_max_size = 0; - wake = true; - } + if (ci->i_auth_cap == cap) { + if (ci->i_requested_max_size > max_size || + !(le32_to_cpu(grant->wanted) & CEPH_CAP_ANY_FILE_WR)) { + /* re-request max_size if necessary */ + ci->i_requested_max_size = 0; + wake = true; + } - ceph_kick_flushing_inode_caps(session, ci); - spin_unlock(&ci->i_ceph_lock); - up_read(&session->s_mdsc->snap_rwsem); + ceph_kick_flushing_inode_caps(session, ci); + spin_unlock(&ci->i_ceph_lock); + up_read(&session->s_mdsc->snap_rwsem); + } } else { spin_unlock(&ci->i_ceph_lock); } -- 2.34.1
