From 695d08fa94ce5bb8d9880e260445fbcf50fa41b4 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Mon, 11 Apr 2011 22:53:32 -0700 Subject: [PATCH] drbd: rcu_read_[un]lock() for all idr accesses that do not sleep Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_main.c | 12 ++++++--- drivers/block/drbd/drbd_nl.c | 41 +++++++++++++++++++++--------- drivers/block/drbd/drbd_receiver.c | 2 ++ drivers/block/drbd/drbd_state.c | 34 ++++++++++++++++++++++--- drivers/block/drbd/drbd_worker.c | 4 +++ 5 files changed, 74 insertions(+), 19 deletions(-) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 563427bfc274..5abbdaf04663 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -453,8 +453,10 @@ void tl_clear(struct drbd_tconn *tconn) } /* ensure bit indicating barrier is required is clear */ + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) clear_bit(CREATE_BARRIER, &mdev->flags); + rcu_read_unlock(); spin_unlock_irq(&tconn->req_lock); } @@ -634,13 +636,15 @@ char *drbd_task_to_thread_name(struct drbd_tconn *tconn, struct task_struct *tas int conn_lowest_minor(struct drbd_tconn *tconn) { - int vnr = 0; struct drbd_conf *mdev; + int vnr = 0, m; + rcu_read_lock(); mdev = idr_get_next(&tconn->volumes, &vnr); - if (!mdev) - return -1; - return mdev_to_minor(mdev); + m = mdev ? mdev_to_minor(mdev) : -1; + rcu_read_unlock(); + + return m; } #ifdef CONFIG_SMP diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index f08fb6f49cd8..60c171b17156 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -372,12 +372,14 @@ static enum drbd_fencing_p highest_fencing_policy(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { if (get_ldev_if_state(mdev, D_CONSISTENT)) { fp = max_t(enum drbd_fencing_p, fp, mdev->ldev->dc.fencing); put_ldev(mdev); } } + rcu_read_unlock(); return fp; } @@ -1624,29 +1626,41 @@ out: static bool conn_resync_running(struct drbd_tconn *tconn) { struct drbd_conf *mdev; + bool rv = false; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { if (mdev->state.conn == C_SYNC_SOURCE || mdev->state.conn == C_SYNC_TARGET || mdev->state.conn == C_PAUSED_SYNC_S || - mdev->state.conn == C_PAUSED_SYNC_T) - return true; + mdev->state.conn == C_PAUSED_SYNC_T) { + rv = true; + break; + } } - return false; + rcu_read_unlock(); + + return rv; } static bool conn_ov_running(struct drbd_tconn *tconn) { struct drbd_conf *mdev; + bool rv = false; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { if (mdev->state.conn == C_VERIFY_S || - mdev->state.conn == C_VERIFY_T) - return true; + mdev->state.conn == C_VERIFY_T) { + rv = true; + break; + } } - return false; + rcu_read_unlock(); + + return rv; } int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info) @@ -1858,26 +1872,28 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) goto fail; } + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, i) { if (get_ldev(mdev)) { enum drbd_fencing_p fp = mdev->ldev->dc.fencing; put_ldev(mdev); if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH) { retcode = ERR_STONITH_AND_PROT_A; - goto fail; + goto fail_rcu_unlock; } } if (mdev->state.role == R_PRIMARY && new_conf->want_lose) { retcode = ERR_DISCARD; - goto fail; + goto fail_rcu_unlock; } if (!mdev->bitmap) { if(drbd_bm_init(mdev)) { retcode = ERR_NOMEM; - goto fail; + goto fail_rcu_unlock; } } } + rcu_read_unlock(); if (new_conf->on_congestion != OC_BLOCK && new_conf->wire_protocol != DRBD_PROT_A) { retcode = ERR_CONG_NOT_PROTO_A; @@ -1991,15 +2007,19 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) retcode = _conn_request_state(tconn, NS(conn, C_UNCONNECTED), CS_VERBOSE); spin_unlock_irq(&tconn->req_lock); + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, i) { mdev->send_cnt = 0; mdev->recv_cnt = 0; kobject_uevent(&disk_to_dev(mdev->vdisk)->kobj, KOBJ_CHANGE); } + rcu_read_unlock(); conn_reconfig_done(tconn); drbd_adm_finish(info, retcode); return 0; +fail_rcu_unlock: + rcu_read_unlock(); fail: kfree(int_dig_in); kfree(int_dig_vv); @@ -2562,8 +2582,6 @@ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb) /* synchronize with drbd_new_tconn/drbd_free_tconn */ mutex_lock(&drbd_cfg_mutex); - /* synchronize with drbd_delete_device */ - rcu_read_lock(); next_tconn: /* revalidate iterator position */ list_for_each_entry(tmp, &drbd_tconns, all_tconn) { @@ -2624,7 +2642,6 @@ next_tconn: } out: - rcu_read_unlock(); mutex_unlock(&drbd_cfg_mutex); /* where to start the next iteration */ cb->args[0] = (long)pos; diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 7e635b24eef7..2b0b0ab90f21 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -4828,11 +4828,13 @@ static int tconn_finish_peer_reqs(struct drbd_tconn *tconn) set_bit(SIGNAL_ASENDER, &tconn->flags); spin_lock_irq(&tconn->req_lock); + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, i) { not_empty = !list_empty(&mdev->done_ee); if (not_empty) break; } + rcu_read_unlock(); spin_unlock_irq(&tconn->req_lock); } while (not_empty); diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c index c479577923c4..52ebd9a9b032 100644 --- a/drivers/block/drbd/drbd_state.c +++ b/drivers/block/drbd/drbd_state.c @@ -55,15 +55,21 @@ static inline bool is_susp(union drbd_state s) bool conn_all_vols_unconf(struct drbd_tconn *tconn) { struct drbd_conf *mdev; + bool rv = true; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { if (mdev->state.disk != D_DISKLESS || mdev->state.conn != C_STANDALONE || - mdev->state.role != R_SECONDARY) - return false; + mdev->state.role != R_SECONDARY) { + rv = false; + break; + } } - return true; + rcu_read_unlock(); + + return rv; } /* Unfortunately the states where not correctly ordered, when @@ -91,8 +97,10 @@ enum drbd_role conn_highest_role(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) role = max_role(role, mdev->state.role); + rcu_read_unlock(); return role; } @@ -103,8 +111,10 @@ enum drbd_role conn_highest_peer(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) peer = max_role(peer, mdev->state.peer); + rcu_read_unlock(); return peer; } @@ -115,8 +125,10 @@ enum drbd_disk_state conn_highest_disk(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) ds = max_t(enum drbd_disk_state, ds, mdev->state.disk); + rcu_read_unlock(); return ds; } @@ -127,8 +139,10 @@ enum drbd_disk_state conn_lowest_disk(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) ds = min_t(enum drbd_disk_state, ds, mdev->state.disk); + rcu_read_unlock(); return ds; } @@ -139,8 +153,10 @@ enum drbd_disk_state conn_highest_pdsk(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) ds = max_t(enum drbd_disk_state, ds, mdev->state.pdsk); + rcu_read_unlock(); return ds; } @@ -151,8 +167,10 @@ enum drbd_conns conn_lowest_conn(struct drbd_tconn *tconn) struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) conn = min_t(enum drbd_conns, conn, mdev->state.conn); + rcu_read_unlock(); return conn; } @@ -1406,12 +1424,14 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused) /* case1: The outdate peer handler is successful: */ if (ns_max.pdsk <= D_OUTDATED) { tl_clear(tconn); + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { if (test_bit(NEW_CUR_UUID, &mdev->flags)) { drbd_uuid_new_current(mdev); clear_bit(NEW_CUR_UUID, &mdev->flags); } } + rcu_read_unlock(); conn_request_state(tconn, (union drbd_state) { { .susp_fen = 1 } }, (union drbd_state) { { .susp_fen = 0 } }, @@ -1419,8 +1439,10 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused) } /* case2: The connection was established again: */ if (ns_min.conn >= C_CONNECTED) { + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) clear_bit(NEW_CUR_UUID, &mdev->flags); + rcu_read_unlock(); spin_lock_irq(&tconn->req_lock); _tl_restart(tconn, RESEND); _conn_request_state(tconn, @@ -1445,6 +1467,7 @@ void conn_old_common_state(struct drbd_tconn *tconn, union drbd_state *pcs, enum struct drbd_conf *mdev; int vnr, first_vol = 1; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { os = mdev->state; @@ -1469,6 +1492,7 @@ void conn_old_common_state(struct drbd_tconn *tconn, union drbd_state *pcs, enum if (cs.pdsk != os.pdsk) flags &= ~CS_DC_PDSK; } + rcu_read_unlock(); *pf |= CS_DC_MASK; *pf &= flags; @@ -1484,6 +1508,7 @@ conn_is_valid_transition(struct drbd_tconn *tconn, union drbd_state mask, union struct drbd_conf *mdev; int vnr; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { os = drbd_read_state(mdev); ns = sanitize_state(mdev, apply_mask_val(os, mask, val), NULL); @@ -1509,6 +1534,7 @@ conn_is_valid_transition(struct drbd_tconn *tconn, union drbd_state mask, union if (rv < SS_SUCCESS) break; } + rcu_read_unlock(); if (rv < SS_SUCCESS && flags & CS_VERBOSE) print_st_err(mdev, os, ns, rv); @@ -1534,6 +1560,7 @@ conn_set_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state if (mask.conn == C_MASK) tconn->cstate = val.conn; + rcu_read_lock(); idr_for_each_entry(&tconn->volumes, mdev, vnr) { os = drbd_read_state(mdev); ns = apply_mask_val(os, mask, val); @@ -1559,6 +1586,7 @@ conn_set_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state ns_min.disk = min_t(enum drbd_disk_state, ns.disk, ns_min.disk); ns_min.pdsk = min_t(enum drbd_disk_state, ns.pdsk, ns_min.pdsk); } + rcu_read_unlock(); ns_min.susp = ns_max.susp = tconn->susp; ns_min.susp_nod = ns_max.susp_nod = tconn->susp_nod; diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c index ef35bbd54084..410900eb2fff 100644 --- a/drivers/block/drbd/drbd_worker.c +++ b/drivers/block/drbd/drbd_worker.c @@ -1348,6 +1348,7 @@ static int _drbd_pause_after(struct drbd_conf *mdev) struct drbd_conf *odev; int i, rv = 0; + rcu_read_lock(); idr_for_each_entry(&minors, odev, i) { if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS) continue; @@ -1355,6 +1356,7 @@ static int _drbd_pause_after(struct drbd_conf *mdev) rv |= (__drbd_set_state(_NS(odev, aftr_isp, 1), CS_HARD, NULL) != SS_NOTHING_TO_DO); } + rcu_read_unlock(); return rv; } @@ -1370,6 +1372,7 @@ static int _drbd_resume_next(struct drbd_conf *mdev) struct drbd_conf *odev; int i, rv = 0; + rcu_read_lock(); idr_for_each_entry(&minors, odev, i) { if (odev->state.conn == C_STANDALONE && odev->state.disk == D_DISKLESS) continue; @@ -1380,6 +1383,7 @@ static int _drbd_resume_next(struct drbd_conf *mdev) != SS_NOTHING_TO_DO) ; } } + rcu_read_unlock(); return rv; } -- 2.20.1