From: Xiubo Li xiubli@redhat.com
[ Upstream commit 1b2ba3c5616e17ff951359e25c658a1c3f146f1e ]
Before waiting for a request's safe reply, we will send the mdlog flush request to the relevant MDS. And this will also flush the mdlog for all the other unsafe requests in the same session, so we can record the last session and no need to flush mdlog again in the next loop. But there still have cases that it may send the mdlog flush requst twice or more, but that should be not often.
Rename wait_unsafe_requests() to flush_mdlog_and_wait_mdsc_unsafe_requests() to make it more descriptive.
[xiubli: fold in MDS request refcount leak fix from Jeff]
URL: https://tracker.ceph.com/issues/55284 URL: https://tracker.ceph.com/issues/55411 Signed-off-by: Xiubo Li xiubli@redhat.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Ilya Dryomov idryomov@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ceph/mds_client.c | 33 +++++++++++++++++++++++++++------ 1 file changed, 27 insertions(+), 6 deletions(-)
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index b34d6286ee90..7744db8f5bb0 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -4709,15 +4709,17 @@ void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc) }
/* - * wait for all write mds requests to flush. + * flush the mdlog and wait for all write mds requests to flush. */ -static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid) +static void flush_mdlog_and_wait_mdsc_unsafe_requests(struct ceph_mds_client *mdsc, + u64 want_tid) { struct ceph_mds_request *req = NULL, *nextreq; + struct ceph_mds_session *last_session = NULL; struct rb_node *n;
mutex_lock(&mdsc->mutex); - dout("wait_unsafe_requests want %lld\n", want_tid); + dout("%s want %lld\n", __func__, want_tid); restart: req = __get_oldest_req(mdsc); while (req && req->r_tid <= want_tid) { @@ -4729,14 +4731,32 @@ static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid) nextreq = NULL; if (req->r_op != CEPH_MDS_OP_SETFILELOCK && (req->r_op & CEPH_MDS_OP_WRITE)) { + struct ceph_mds_session *s = req->r_session; + + if (!s) { + req = nextreq; + continue; + } + /* write op */ ceph_mdsc_get_request(req); if (nextreq) ceph_mdsc_get_request(nextreq); + s = ceph_get_mds_session(s); mutex_unlock(&mdsc->mutex); - dout("wait_unsafe_requests wait on %llu (want %llu)\n", + + /* send flush mdlog request to MDS */ + if (last_session != s) { + send_flush_mdlog(s); + ceph_put_mds_session(last_session); + last_session = s; + } else { + ceph_put_mds_session(s); + } + dout("%s wait on %llu (want %llu)\n", __func__, req->r_tid, want_tid); wait_for_completion(&req->r_safe_completion); + mutex_lock(&mdsc->mutex); ceph_mdsc_put_request(req); if (!nextreq) @@ -4751,7 +4771,8 @@ static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid) req = nextreq; } mutex_unlock(&mdsc->mutex); - dout("wait_unsafe_requests done\n"); + ceph_put_mds_session(last_session); + dout("%s done\n", __func__); }
void ceph_mdsc_sync(struct ceph_mds_client *mdsc) @@ -4780,7 +4801,7 @@ void ceph_mdsc_sync(struct ceph_mds_client *mdsc) dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
- wait_unsafe_requests(mdsc, want_tid); + flush_mdlog_and_wait_mdsc_unsafe_requests(mdsc, want_tid); wait_caps_flush(mdsc, want_flush); }