From 745a8e3bccbc6adae69a98ddc525e529aa44636e Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Thu, 14 May 2015 17:22:42 +0800 Subject: ceph: don't pre-allocate space for cap release messages Previously we pre-allocate cap release messages for each caps. This wastes lots of memory when there are large amount of caps. This patch make the code not pre-allocate the cap release messages. Instead, we add the corresponding ceph_cap struct to a list when releasing a cap. Later when flush cap releases is needed, we allocate the cap release messages dynamically. Signed-off-by: Yan, Zheng --- fs/ceph/caps.c | 85 +++++++------------- fs/ceph/mds_client.c | 223 ++++++++++++++++++++------------------------------- fs/ceph/mds_client.h | 3 - fs/ceph/super.h | 20 +++-- 4 files changed, 129 insertions(+), 202 deletions(-) (limited to 'fs/ceph') diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index bbd969e16a01..245ca381a6dc 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -926,16 +926,6 @@ void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release) /* remove from session list */ spin_lock(&session->s_cap_lock); - /* - * s_cap_reconnect is protected by s_cap_lock. no one changes - * s_cap_gen while session is in the reconnect state. - */ - if (queue_release && - (!session->s_cap_reconnect || - cap->cap_gen == session->s_cap_gen)) - __queue_cap_release(session, ci->i_vino.ino, cap->cap_id, - cap->mseq, cap->issue_seq); - if (session->s_cap_iterator == cap) { /* not yet, we are iterating over this very cap */ dout("__ceph_remove_cap delaying %p removal from session %p\n", @@ -948,6 +938,25 @@ void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release) } /* protect backpointer with s_cap_lock: see iterate_session_caps */ cap->ci = NULL; + + /* + * s_cap_reconnect is protected by s_cap_lock. no one changes + * s_cap_gen while session is in the reconnect state. + */ + if (queue_release && + (!session->s_cap_reconnect || cap->cap_gen == session->s_cap_gen)) { + cap->queue_release = 1; + if (removed) { + list_add_tail(&cap->session_caps, + &session->s_cap_releases); + session->s_num_cap_releases++; + removed = 0; + } + } else { + cap->queue_release = 0; + } + cap->cap_ino = ci->i_vino.ino; + spin_unlock(&session->s_cap_lock); /* remove from inode list */ @@ -1053,44 +1062,6 @@ static int send_cap_msg(struct ceph_mds_session *session, return 0; } -void __queue_cap_release(struct ceph_mds_session *session, - u64 ino, u64 cap_id, u32 migrate_seq, - u32 issue_seq) -{ - struct ceph_msg *msg; - struct ceph_mds_cap_release *head; - struct ceph_mds_cap_item *item; - - BUG_ON(!session->s_num_cap_releases); - msg = list_first_entry(&session->s_cap_releases, - struct ceph_msg, list_head); - - dout(" adding %llx release to mds%d msg %p (%d left)\n", - ino, session->s_mds, msg, session->s_num_cap_releases); - - BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE); - head = msg->front.iov_base; - le32_add_cpu(&head->num, 1); - item = msg->front.iov_base + msg->front.iov_len; - item->ino = cpu_to_le64(ino); - item->cap_id = cpu_to_le64(cap_id); - item->migrate_seq = cpu_to_le32(migrate_seq); - item->seq = cpu_to_le32(issue_seq); - - session->s_num_cap_releases--; - - msg->front.iov_len += sizeof(*item); - if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) { - dout(" release msg %p full\n", msg); - list_move_tail(&msg->list_head, &session->s_cap_releases_done); - } else { - dout(" release msg %p at %d/%d (%d)\n", msg, - (int)le32_to_cpu(head->num), - (int)CEPH_CAPS_PER_RELEASE, - (int)msg->front.iov_len); - } -} - /* * Queue cap releases when an inode is dropped from our cache. Since * inode is about to be destroyed, there is no need for i_ceph_lock. @@ -3051,7 +3022,6 @@ retry: mutex_lock_nested(&session->s_mutex, SINGLE_DEPTH_NESTING); } - ceph_add_cap_releases(mdsc, tsession); new_cap = ceph_get_cap(mdsc, NULL); } else { WARN_ON(1); @@ -3247,16 +3217,20 @@ void ceph_handle_caps(struct ceph_mds_session *session, dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq, (unsigned)seq); - if (op == CEPH_CAP_OP_IMPORT) - ceph_add_cap_releases(mdsc, session); - if (!inode) { dout(" i don't have ino %llx\n", vino.ino); if (op == CEPH_CAP_OP_IMPORT) { + cap = ceph_get_cap(mdsc, NULL); + cap->cap_ino = vino.ino; + cap->queue_release = 1; + cap->cap_id = cap_id; + cap->mseq = mseq; + cap->seq = seq; spin_lock(&session->s_cap_lock); - __queue_cap_release(session, vino.ino, cap_id, - mseq, seq); + list_add_tail(&cap->session_caps, + &session->s_cap_releases); + session->s_num_cap_releases++; spin_unlock(&session->s_cap_lock); } goto flush_cap_releases; @@ -3332,11 +3306,10 @@ void ceph_handle_caps(struct ceph_mds_session *session, flush_cap_releases: /* - * send any full release message to try to move things + * send any cap release message to try to move things * along for the mds (who clearly thinks we still have this * cap). */ - ceph_add_cap_releases(mdsc, session); ceph_send_cap_releases(mdsc, session); done: diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 2bb9264b9225..76eb14489bfa 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -458,7 +458,6 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, s->s_cap_reconnect = 0; s->s_cap_iterator = NULL; INIT_LIST_HEAD(&s->s_cap_releases); - INIT_LIST_HEAD(&s->s_cap_releases_done); INIT_LIST_HEAD(&s->s_cap_flushing); INIT_LIST_HEAD(&s->s_cap_snaps_flushing); @@ -998,27 +997,25 @@ void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, * session caps */ -/* - * Free preallocated cap messages assigned to this session - */ -static void cleanup_cap_releases(struct ceph_mds_session *session) +/* caller holds s_cap_lock, we drop it */ +static void cleanup_cap_releases(struct ceph_mds_client *mdsc, + struct ceph_mds_session *session) + __releases(session->s_cap_lock) { - struct ceph_msg *msg; + LIST_HEAD(tmp_list); + list_splice_init(&session->s_cap_releases, &tmp_list); + session->s_num_cap_releases = 0; + spin_unlock(&session->s_cap_lock); - spin_lock(&session->s_cap_lock); - while (!list_empty(&session->s_cap_releases)) { - msg = list_first_entry(&session->s_cap_releases, - struct ceph_msg, list_head); - list_del_init(&msg->list_head); - ceph_msg_put(msg); - } - while (!list_empty(&session->s_cap_releases_done)) { - msg = list_first_entry(&session->s_cap_releases_done, - struct ceph_msg, list_head); - list_del_init(&msg->list_head); - ceph_msg_put(msg); + dout("cleanup_cap_releases mds%d\n", session->s_mds); + while (!list_empty(&tmp_list)) { + struct ceph_cap *cap; + /* zero out the in-progress message */ + cap = list_first_entry(&tmp_list, + struct ceph_cap, session_caps); + list_del(&cap->session_caps); + ceph_put_cap(mdsc, cap); } - spin_unlock(&session->s_cap_lock); } static void cleanup_session_requests(struct ceph_mds_client *mdsc, @@ -1095,10 +1092,16 @@ static int iterate_session_caps(struct ceph_mds_session *session, dout("iterate_session_caps finishing cap %p removal\n", cap); BUG_ON(cap->session != session); + cap->session = NULL; list_del_init(&cap->session_caps); session->s_nr_caps--; - cap->session = NULL; - old_cap = cap; /* put_cap it w/o locks held */ + if (cap->queue_release) { + list_add_tail(&cap->session_caps, + &session->s_cap_releases); + session->s_num_cap_releases++; + } else { + old_cap = cap; /* put_cap it w/o locks held */ + } } if (ret < 0) goto out; @@ -1191,11 +1194,12 @@ static void remove_session_caps(struct ceph_mds_session *session) spin_lock(&session->s_cap_lock); } } - spin_unlock(&session->s_cap_lock); + + // drop cap expires and unlock s_cap_lock + cleanup_cap_releases(session->s_mdsc, session); BUG_ON(session->s_nr_caps > 0); BUG_ON(!list_empty(&session->s_cap_flushing)); - cleanup_cap_releases(session); } /* @@ -1418,76 +1422,10 @@ static int trim_caps(struct ceph_mds_client *mdsc, session->s_trim_caps = 0; } - ceph_add_cap_releases(mdsc, session); ceph_send_cap_releases(mdsc, session); return 0; } -/* - * Allocate cap_release messages. If there is a partially full message - * in the queue, try to allocate enough to cover it's remainder, so that - * we can send it immediately. - * - * Called under s_mutex. - */ -int ceph_add_cap_releases(struct ceph_mds_client *mdsc, - struct ceph_mds_session *session) -{ - struct ceph_msg *msg, *partial = NULL; - struct ceph_mds_cap_release *head; - int err = -ENOMEM; - int extra = mdsc->fsc->mount_options->cap_release_safety; - int num; - - dout("add_cap_releases %p mds%d extra %d\n", session, session->s_mds, - extra); - - spin_lock(&session->s_cap_lock); - - if (!list_empty(&session->s_cap_releases)) { - msg = list_first_entry(&session->s_cap_releases, - struct ceph_msg, - list_head); - head = msg->front.iov_base; - num = le32_to_cpu(head->num); - if (num) { - dout(" partial %p with (%d/%d)\n", msg, num, - (int)CEPH_CAPS_PER_RELEASE); - extra += CEPH_CAPS_PER_RELEASE - num; - partial = msg; - } - } - while (session->s_num_cap_releases < session->s_nr_caps + extra) { - spin_unlock(&session->s_cap_lock); - msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE, - GFP_NOFS, false); - if (!msg) - goto out_unlocked; - dout("add_cap_releases %p msg %p now %d\n", session, msg, - (int)msg->front.iov_len); - head = msg->front.iov_base; - head->num = cpu_to_le32(0); - msg->front.iov_len = sizeof(*head); - spin_lock(&session->s_cap_lock); - list_add(&msg->list_head, &session->s_cap_releases); - session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE; - } - - if (partial) { - head = partial->front.iov_base; - num = le32_to_cpu(head->num); - dout(" queueing partial %p with %d/%d\n", partial, num, - (int)CEPH_CAPS_PER_RELEASE); - list_move_tail(&partial->list_head, - &session->s_cap_releases_done); - session->s_num_cap_releases -= CEPH_CAPS_PER_RELEASE - num; - } - err = 0; - spin_unlock(&session->s_cap_lock); -out_unlocked: - return err; -} - static int check_cap_flush(struct ceph_inode_info *ci, u64 want_flush_seq, u64 want_snap_seq) { @@ -1590,60 +1528,74 @@ static void wait_caps_flush(struct ceph_mds_client *mdsc, void ceph_send_cap_releases(struct ceph_mds_client *mdsc, struct ceph_mds_session *session) { - struct ceph_msg *msg; + struct ceph_msg *msg = NULL; + struct ceph_mds_cap_release *head; + struct ceph_mds_cap_item *item; + struct ceph_cap *cap; + LIST_HEAD(tmp_list); + int num_cap_releases; - dout("send_cap_releases mds%d\n", session->s_mds); spin_lock(&session->s_cap_lock); - while (!list_empty(&session->s_cap_releases_done)) { - msg = list_first_entry(&session->s_cap_releases_done, - struct ceph_msg, list_head); - list_del_init(&msg->list_head); - spin_unlock(&session->s_cap_lock); - msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); - dout("send_cap_releases mds%d %p\n", session->s_mds, msg); - ceph_con_send(&session->s_con, msg); - spin_lock(&session->s_cap_lock); - } +again: + list_splice_init(&session->s_cap_releases, &tmp_list); + num_cap_releases = session->s_num_cap_releases; + session->s_num_cap_releases = 0; spin_unlock(&session->s_cap_lock); -} - -static void discard_cap_releases(struct ceph_mds_client *mdsc, - struct ceph_mds_session *session) -{ - struct ceph_msg *msg; - struct ceph_mds_cap_release *head; - unsigned num; - dout("discard_cap_releases mds%d\n", session->s_mds); + while (!list_empty(&tmp_list)) { + if (!msg) { + msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, + PAGE_CACHE_SIZE, GFP_NOFS, false); + if (!msg) + goto out_err; + head = msg->front.iov_base; + head->num = cpu_to_le32(0); + msg->front.iov_len = sizeof(*head); + } + cap = list_first_entry(&tmp_list, struct ceph_cap, + session_caps); + list_del(&cap->session_caps); + num_cap_releases--; - if (!list_empty(&session->s_cap_releases)) { - /* zero out the in-progress message */ - msg = list_first_entry(&session->s_cap_releases, - struct ceph_msg, list_head); head = msg->front.iov_base; - num = le32_to_cpu(head->num); - dout("discard_cap_releases mds%d %p %u\n", - session->s_mds, msg, num); - head->num = cpu_to_le32(0); - msg->front.iov_len = sizeof(*head); - session->s_num_cap_releases += num; + le32_add_cpu(&head->num, 1); + item = msg->front.iov_base + msg->front.iov_len; + item->ino = cpu_to_le64(cap->cap_ino); + item->cap_id = cpu_to_le64(cap->cap_id); + item->migrate_seq = cpu_to_le32(cap->mseq); + item->seq = cpu_to_le32(cap->issue_seq); + msg->front.iov_len += sizeof(*item); + + ceph_put_cap(mdsc, cap); + + if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) { + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + dout("send_cap_releases mds%d %p\n", session->s_mds, msg); + ceph_con_send(&session->s_con, msg); + msg = NULL; + } } - /* requeue completed messages */ - while (!list_empty(&session->s_cap_releases_done)) { - msg = list_first_entry(&session->s_cap_releases_done, - struct ceph_msg, list_head); - list_del_init(&msg->list_head); + BUG_ON(num_cap_releases != 0); - head = msg->front.iov_base; - num = le32_to_cpu(head->num); - dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, - num); - session->s_num_cap_releases += num; - head->num = cpu_to_le32(0); - msg->front.iov_len = sizeof(*head); - list_add(&msg->list_head, &session->s_cap_releases); + spin_lock(&session->s_cap_lock); + if (!list_empty(&session->s_cap_releases)) + goto again; + spin_unlock(&session->s_cap_lock); + + if (msg) { + msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); + dout("send_cap_releases mds%d %p\n", session->s_mds, msg); + ceph_con_send(&session->s_con, msg); } + return; +out_err: + pr_err("send_cap_releases mds%d, failed to allocate message\n", + session->s_mds); + spin_lock(&session->s_cap_lock); + list_splice(&tmp_list, &session->s_cap_releases); + session->s_num_cap_releases += num_cap_releases; + spin_unlock(&session->s_cap_lock); } /* @@ -2529,7 +2481,6 @@ out_err: } mutex_unlock(&mdsc->mutex); - ceph_add_cap_releases(mdsc, req->r_session); mutex_unlock(&session->s_mutex); /* kick calling process */ @@ -2921,8 +2872,7 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, */ session->s_cap_reconnect = 1; /* drop old cap expires; we're about to reestablish that state */ - discard_cap_releases(mdsc, session); - spin_unlock(&session->s_cap_lock); + cleanup_cap_releases(mdsc, session); /* trim unused caps to reduce MDS's cache rejoin time */ if (mdsc->fsc->sb->s_root) @@ -3385,7 +3335,6 @@ static void delayed_work(struct work_struct *work) send_renew_caps(mdsc, s); else ceph_con_keepalive(&s->s_con); - ceph_add_cap_releases(mdsc, s); if (s->s_state == CEPH_MDS_SESSION_OPEN || s->s_state == CEPH_MDS_SESSION_HUNG) ceph_send_cap_releases(mdsc, s); diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index bf24d88cfeb2..294fa23a7df6 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -139,7 +139,6 @@ struct ceph_mds_session { int s_cap_reconnect; int s_readonly; struct list_head s_cap_releases; /* waiting cap_release messages */ - struct list_head s_cap_releases_done; /* ready to send */ struct ceph_cap *s_cap_iterator; /* protected by mutex */ @@ -389,8 +388,6 @@ static inline void ceph_mdsc_put_request(struct ceph_mds_request *req) kref_put(&req->r_kref, ceph_mdsc_release_request); } -extern int ceph_add_cap_releases(struct ceph_mds_client *mdsc, - struct ceph_mds_session *session); extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc, struct ceph_mds_session *session); diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 4ef1ae92c2a6..c4961353d058 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -122,11 +122,21 @@ struct ceph_cap { struct rb_node ci_node; /* per-ci cap tree */ struct ceph_mds_session *session; struct list_head session_caps; /* per-session caplist */ - int mds; u64 cap_id; /* unique cap id (mds provided) */ - int issued; /* latest, from the mds */ - int implemented; /* implemented superset of issued (for revocation) */ - int mds_wanted; + union { + /* in-use caps */ + struct { + int issued; /* latest, from the mds */ + int implemented; /* implemented superset of + issued (for revocation) */ + int mds, mds_wanted; + }; + /* caps to release */ + struct { + u64 cap_ino; + int queue_release; + }; + }; u32 seq, issue_seq, mseq; u32 cap_gen; /* active/stale cycle */ unsigned long last_used; @@ -845,8 +855,6 @@ extern void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap); extern int ceph_is_any_caps(struct inode *inode); -extern void __queue_cap_release(struct ceph_mds_session *session, u64 ino, - u64 cap_id, u32 migrate_seq, u32 issue_seq); extern void ceph_queue_caps_release(struct inode *inode); extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc); extern int ceph_fsync(struct file *file, loff_t start, loff_t end, -- cgit v1.2.3