/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 only, * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 for more details (a copy is included * in the LICENSE file that accompanied this code). * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * * GPL HEADER END */ /* * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * * Copyright (c) 2012, 2013, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ * Lustre is a trademark of Sun Microsystems, Inc. * * lustre/osp/osp_sync.c * * Lustre OST Proxy Device * * Author: Alex Zhuravlev * Author: Mikhail Pershin */ #define DEBUG_SUBSYSTEM S_MDS #include #include #include "osp_internal.h" static int osp_sync_id_traction_init(struct osp_device *d); static void osp_sync_id_traction_fini(struct osp_device *d); static __u32 osp_sync_id_get(struct osp_device *d, __u32 id); static void osp_sync_remove_from_tracker(struct osp_device *d); /* * this is a components of OSP implementing synchronization between MDS and OST * it llogs all interesting changes (currently it's uig/gid change and object * destroy) atomically, then makes sure changes hit OST storage * * we have 4 queues of work: * * the first queue is llog itself, once read a change is stored in 2nd queue * in form of RPC (but RPC isn't fired yet). * * the second queue (opd_syn_waiting_for_commit) holds changes awaiting local * commit. once change is committed locally it migrates onto 3rd queue. * * the third queue (opd_syn_committed_here) holds changes committed locally, * but not sent to OST (as the pipe can be full). once pipe becomes non-full * we take a change from the queue and fire corresponded RPC. * * once RPC is reported committed by OST (using regular last_committed mech.) * the change jumps into 4th queue (opd_syn_committed_there), now we can * cancel corresponded llog record and release RPC * * opd_syn_changes is a number of unread llog records (to be processed). * notice this number doesn't include llog records from previous boots. * with OSP_SYN_THRESHOLD we try to batch processing a bit (TO BE IMPLEMENTED) * * opd_syn_rpc_in_progress is a number of requests in 2-4 queues. * we control this with OSP_MAX_IN_PROGRESS so that OSP don't consume * too much memory -- how to deal with 1000th OSTs ? batching could help? * * opd_syn_rpc_in_flight is a number of RPC in flight. * we control this with OSP_MAX_IN_FLIGHT */ /* XXX: do math to learn reasonable threshold * should it be ~ number of changes fitting bulk? */ #define OSP_SYN_THRESHOLD 10 #define OSP_MAX_IN_FLIGHT 8 #define OSP_MAX_IN_PROGRESS 4096 #define OSP_JOB_MAGIC 0x26112005 /** * Return status: whether OSP thread should keep running * * \param[in] d OSP device * * \retval 1 should keep running * \retval 0 should stop */ static inline int osp_sync_running(struct osp_device *d) { return !!(d->opd_syn_thread.t_flags & SVC_RUNNING); } /** * Check status: whether OSP thread has stopped * * \param[in] d OSP device * * \retval 0 still running * \retval 1 stopped */ static inline int osp_sync_stopped(struct osp_device *d) { return !!(d->opd_syn_thread.t_flags & SVC_STOPPED); } /* ** Check for new changes to sync * * \param[in] d OSP device * * \retval 1 there are changes * \retval 0 there are no changes */ static inline int osp_sync_has_new_job(struct osp_device *d) { return ((d->opd_syn_last_processed_id < d->opd_syn_last_used_id) && (d->opd_syn_last_processed_id < d->opd_syn_last_committed_id)) || (d->opd_syn_prev_done == 0); } static inline int osp_sync_low_in_progress(struct osp_device *d) { return d->opd_syn_rpc_in_progress < d->opd_syn_max_rpc_in_progress; } /** * Check for room in the network pipe to OST * * \param[in] d OSP device * * \retval 1 there is room * \retval 0 no room, the pipe is full */ static inline int osp_sync_low_in_flight(struct osp_device *d) { return d->opd_syn_rpc_in_flight < d->opd_syn_max_rpc_in_flight; } /** * Wake up check for the main sync thread * * \param[in] d OSP device * * \retval 1 time to wake up * \retval 0 no need to wake up */ static inline int osp_sync_has_work(struct osp_device *d) { /* has new/old changes and low in-progress? */ if (osp_sync_has_new_job(d) && osp_sync_low_in_progress(d) && osp_sync_low_in_flight(d) && d->opd_imp_connected) return 1; /* has remotely committed? */ if (!list_empty(&d->opd_syn_committed_there)) return 1; return 0; } #define osp_sync_check_for_work(d) \ { \ if (osp_sync_has_work(d)) { \ wake_up(&d->opd_syn_waitq); \ } \ } void __osp_sync_check_for_work(struct osp_device *d) { osp_sync_check_for_work(d); } /** * Check and return ready-for-new status. * * The thread processing llog record uses this function to check whether * it's time to take another record and process it. The number of conditions * must be met: the connection should be ready, RPCs in flight not exceeding * the limit, the record is committed locally, etc (see the lines below). * * \param[in] d OSP device * \param[in] rec next llog record to process * * \retval 0 not ready * \retval 1 ready */ static inline int osp_sync_can_process_new(struct osp_device *d, struct llog_rec_hdr *rec) { LASSERT(d); if (unlikely(atomic_read(&d->opd_syn_barrier) > 0)) return 0; if (!osp_sync_low_in_progress(d)) return 0; if (!osp_sync_low_in_flight(d)) return 0; if (!d->opd_imp_connected) return 0; if (d->opd_syn_prev_done == 0) return 1; if (d->opd_syn_changes == 0) return 0; if (rec == NULL || rec->lrh_id <= d->opd_syn_last_committed_id) return 1; return 0; } /** * Declare intention to add a new change. * * With regard to OSD API, we have to declare any changes ahead. In this * case we declare an intention to add a llog record representing the * change on the local storage. * * \param[in] env LU environment provided by the caller * \param[in] o OSP object * \param[in] type type of change: MDS_UNLINK64_REC or MDS_SETATTR64_REC * \param[in] th transaction handle (local) * * \retval 0 on success * \retval negative negated errno on error */ int osp_sync_declare_add(const struct lu_env *env, struct osp_object *o, llog_op_type type, struct thandle *th) { struct osp_thread_info *osi = osp_env_info(env); struct osp_device *d = lu2osp_dev(o->opo_obj.do_lu.lo_dev); struct llog_ctxt *ctxt; int rc; ENTRY; /* it's a layering violation, to access internals of th, * but we can do this as a sanity check, for a while */ LASSERT(th->th_dev == d->opd_storage); switch (type) { case MDS_UNLINK64_REC: osi->osi_hdr.lrh_len = sizeof(struct llog_unlink64_rec); break; case MDS_SETATTR64_REC: osi->osi_hdr.lrh_len = sizeof(struct llog_setattr64_rec); break; default: LBUG(); } /* we want ->dt_trans_start() to allocate per-thandle structure */ th->th_tags |= LCT_OSP_THREAD; ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT); LASSERT(ctxt); rc = llog_declare_add(env, ctxt->loc_handle, &osi->osi_hdr, th); llog_ctxt_put(ctxt); RETURN(rc); } /** * Generate a llog record for a given change. * * Generates a llog record for the change passed. The change can be of two * types: unlink and setattr. The record gets an ID which later will be * used to track commit status of the change. For unlink changes, the caller * can supply a starting FID and the count of the objects to destroy. For * setattr the caller should apply attributes to apply. * * * \param[in] env LU environment provided by the caller * \param[in] d OSP device * \param[in] fid fid of the object the change should be applied to * \param[in] type type of change: MDS_UNLINK64_REC or MDS_SETATTR64_REC * \param[in] count count of objects to destroy * \param[in] th transaction handle (local) * \param[in] attr attributes for setattr * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_add_rec(const struct lu_env *env, struct osp_device *d, const struct lu_fid *fid, llog_op_type type, int count, struct thandle *th, const struct lu_attr *attr) { struct osp_thread_info *osi = osp_env_info(env); struct llog_ctxt *ctxt; struct osp_txn_info *txn; int rc; ENTRY; /* it's a layering violation, to access internals of th, * but we can do this as a sanity check, for a while */ LASSERT(th->th_dev == d->opd_storage); switch (type) { case MDS_UNLINK64_REC: osi->osi_hdr.lrh_len = sizeof(osi->osi_unlink); osi->osi_hdr.lrh_type = MDS_UNLINK64_REC; osi->osi_unlink.lur_fid = *fid; osi->osi_unlink.lur_count = count; break; case MDS_SETATTR64_REC: rc = fid_to_ostid(fid, &osi->osi_oi); LASSERT(rc == 0); osi->osi_hdr.lrh_len = sizeof(osi->osi_setattr); osi->osi_hdr.lrh_type = MDS_SETATTR64_REC; osi->osi_setattr.lsr_oi = osi->osi_oi; LASSERT(attr); osi->osi_setattr.lsr_uid = attr->la_uid; osi->osi_setattr.lsr_gid = attr->la_gid; osi->osi_setattr.lsr_valid = ((attr->la_valid & LA_UID) ? OBD_MD_FLUID : 0) | ((attr->la_valid & LA_GID) ? OBD_MD_FLGID : 0); break; default: LBUG(); } txn = osp_txn_info(&th->th_ctx); LASSERT(txn); txn->oti_current_id = osp_sync_id_get(d, txn->oti_current_id); osi->osi_hdr.lrh_id = txn->oti_current_id; ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT); if (ctxt == NULL) RETURN(-ENOMEM); rc = llog_add(env, ctxt->loc_handle, &osi->osi_hdr, &osi->osi_cookie, th); llog_ctxt_put(ctxt); CDEBUG(D_OTHER, "%s: new record "DOSTID":%lu/%lu: %d\n", d->opd_obd->obd_name, POSTID(&osi->osi_cookie.lgc_lgl.lgl_oi), (unsigned long) osi->osi_cookie.lgc_lgl.lgl_ogen, (unsigned long) osi->osi_cookie.lgc_index, rc); if (rc > 0) rc = 0; if (likely(rc == 0)) { spin_lock(&d->opd_syn_lock); d->opd_syn_changes++; spin_unlock(&d->opd_syn_lock); } RETURN(rc); } int osp_sync_add(const struct lu_env *env, struct osp_object *o, llog_op_type type, struct thandle *th, const struct lu_attr *attr) { return osp_sync_add_rec(env, lu2osp_dev(o->opo_obj.do_lu.lo_dev), lu_object_fid(&o->opo_obj.do_lu), type, 1, th, attr); } int osp_sync_gap(const struct lu_env *env, struct osp_device *d, struct lu_fid *fid, int lost, struct thandle *th) { return osp_sync_add_rec(env, d, fid, MDS_UNLINK64_REC, lost, th, NULL); } /* * it's quite obvious we can't maintain all the structures in the memory: * while OST is down, MDS can be processing thousands and thousands of unlinks * filling persistent llogs and in-core respresentation * * this doesn't scale at all. so we need basically the following: * a) destroy/setattr append llog records * b) once llog has grown to X records, we process first Y committed records * * once record R is found via llog_process(), it becomes committed after any * subsequent commit callback (at the most) */ /** * ptlrpc commit callback. * * The callback is called by PTLRPC when a RPC is reported committed by the * target (OST). We register the callback for the every RPC applying a change * from the llog. This way we know then the llog records can be cancelled. * Notice the callback can be called when OSP is finishing. We can detect this * checking that actual transno in the request is less or equal of known * committed transno (see osp_sync_process_committed() for the details). * XXX: this is pretty expensive and can be improved later using batching. * * \param[in] req request */ static void osp_sync_request_commit_cb(struct ptlrpc_request *req) { struct osp_device *d = req->rq_cb_data; CDEBUG(D_HA, "commit req %p, transno "LPU64"\n", req, req->rq_transno); if (unlikely(req->rq_transno == 0)) return; /* do not do any opd_dyn_rpc_* accounting here * it's done in osp_sync_interpret sooner or later */ LASSERT(d); LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC); LASSERT(list_empty(&req->rq_exp_list)); ptlrpc_request_addref(req); spin_lock(&d->opd_syn_lock); list_add(&req->rq_exp_list, &d->opd_syn_committed_there); spin_unlock(&d->opd_syn_lock); /* XXX: some batching wouldn't hurt */ wake_up(&d->opd_syn_waitq); } /** * RPC interpretation callback. * * The callback is called by ptlrpc when RPC is replied. Now we have to decide * whether we should: * - put request on a special list to wait until it's committed by the target, * if the request is succesful * - schedule llog record cancel if no target object is found * - try later (essentially after reboot) in case of unexpected error * * \param[in] env LU environment provided by the caller * \param[in] req request replied * \param[in] aa callback data * \param[in] rc result of RPC * * \retval 0 always */ static int osp_sync_interpret(const struct lu_env *env, struct ptlrpc_request *req, void *aa, int rc) { struct osp_device *d = req->rq_cb_data; if (req->rq_svc_thread != (void *) OSP_JOB_MAGIC) DEBUG_REQ(D_ERROR, req, "bad magic %p\n", req->rq_svc_thread); LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC); LASSERT(d); CDEBUG(D_HA, "reply req %p/%d, rc %d, transno %u\n", req, atomic_read(&req->rq_refcount), rc, (unsigned) req->rq_transno); LASSERT(rc || req->rq_transno); if (rc == -ENOENT) { /* * we tried to destroy object or update attributes, * but object doesn't exist anymore - cancell llog record */ LASSERT(req->rq_transno == 0); LASSERT(list_empty(&req->rq_exp_list)); ptlrpc_request_addref(req); spin_lock(&d->opd_syn_lock); list_add(&req->rq_exp_list, &d->opd_syn_committed_there); spin_unlock(&d->opd_syn_lock); wake_up(&d->opd_syn_waitq); } else if (rc) { struct obd_import *imp = req->rq_import; /* * error happened, we'll try to repeat on next boot ? */ LASSERTF(req->rq_transno == 0 || req->rq_import_generation < imp->imp_generation, "transno "LPU64", rc %d, gen: req %d, imp %d\n", req->rq_transno, rc, req->rq_import_generation, imp->imp_generation); if (req->rq_transno == 0) { /* this is the last time we see the request * if transno is not zero, then commit cb * will be called at some point */ LASSERT(d->opd_syn_rpc_in_progress > 0); spin_lock(&d->opd_syn_lock); d->opd_syn_rpc_in_progress--; spin_unlock(&d->opd_syn_lock); } wake_up(&d->opd_syn_waitq); } else if (d->opd_pre != NULL && unlikely(d->opd_pre_status == -ENOSPC)) { /* * if current status is -ENOSPC (lack of free space on OST) * then we should poll OST immediately once object destroy * is replied */ osp_statfs_need_now(d); } LASSERT(d->opd_syn_rpc_in_flight > 0); spin_lock(&d->opd_syn_lock); d->opd_syn_rpc_in_flight--; spin_unlock(&d->opd_syn_lock); if (unlikely(atomic_read(&d->opd_syn_barrier) > 0)) wake_up(&d->opd_syn_barrier_waitq); CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n", d->opd_obd->obd_name, d->opd_syn_rpc_in_flight, d->opd_syn_rpc_in_progress); osp_sync_check_for_work(d); return 0; } /* ** Add request to ptlrpc queue. * * This is just a tiny helper function to put the request on the sending list * * \param[in] d OSP device * \param[in] req request */ static void osp_sync_send_new_rpc(struct osp_device *d, struct ptlrpc_request *req) { LASSERT(d->opd_syn_rpc_in_flight <= d->opd_syn_max_rpc_in_flight); LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC); ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1); } /** * Allocate and prepare RPC for a new change. * * The function allocates and initializes an RPC which will be sent soon to * apply the change to the target OST. The request is initialized from the * llog record passed. Notice only the fields common to all type of changes * are initialized. * * \param[in] d OSP device * \param[in] llh llog handle where the record is stored * \param[in] h llog record * \param[in] op type of the change * \param[in] format request format to be used * * \retval pointer new request on success * \retval ERR_PTR(errno) on error */ static struct ptlrpc_request *osp_sync_new_job(struct osp_device *d, struct llog_handle *llh, struct llog_rec_hdr *h, ost_cmd_t op, const struct req_format *format) { struct ptlrpc_request *req; struct ost_body *body; struct obd_import *imp; int rc; /* Prepare the request */ imp = d->opd_obd->u.cli.cl_import; LASSERT(imp); req = ptlrpc_request_alloc(imp, format); if (req == NULL) RETURN(ERR_PTR(-ENOMEM)); rc = ptlrpc_request_pack(req, LUSTRE_OST_VERSION, op); if (rc) { ptlrpc_req_finished(req); return ERR_PTR(rc); } /* * this is a trick: to save on memory allocations we put cookie * into the request, but don't set corresponded flag in o_valid * so that OST doesn't interpret this cookie. once the request * is committed on OST we take cookie from the request and cancel */ body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY); LASSERT(body); body->oa.o_lcookie.lgc_lgl = llh->lgh_id; body->oa.o_lcookie.lgc_subsys = LLOG_MDS_OST_ORIG_CTXT; body->oa.o_lcookie.lgc_index = h->lrh_index; INIT_LIST_HEAD(&req->rq_exp_list); req->rq_svc_thread = (void *) OSP_JOB_MAGIC; req->rq_interpret_reply = osp_sync_interpret; req->rq_commit_cb = osp_sync_request_commit_cb; req->rq_cb_data = d; ptlrpc_request_set_replen(req); return req; } /** * Generate a request for setattr change. * * The function prepares a new RPC, initializes it with setattr specific * bits and send the RPC. * * \param[in] d OSP device * \param[in] llh llog handle where the record is stored * \param[in] h llog record * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_new_setattr_job(struct osp_device *d, struct llog_handle *llh, struct llog_rec_hdr *h) { struct llog_setattr64_rec *rec = (struct llog_setattr64_rec *)h; struct ptlrpc_request *req; struct ost_body *body; ENTRY; LASSERT(h->lrh_type == MDS_SETATTR64_REC); /* lsr_valid can only be 0 or have OBD_MD_{FLUID,FLGID} set, * so no bits other than these should be set. */ if ((rec->lsr_valid & ~(OBD_MD_FLUID | OBD_MD_FLGID)) != 0) { CERROR("%s: invalid setattr record, lsr_valid:"LPU64"\n", d->opd_obd->obd_name, rec->lsr_valid); /* return 0 so that sync thread can continue processing * other records. */ RETURN(0); } req = osp_sync_new_job(d, llh, h, OST_SETATTR, &RQF_OST_SETATTR); if (IS_ERR(req)) RETURN(PTR_ERR(req)); body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY); LASSERT(body); body->oa.o_oi = rec->lsr_oi; body->oa.o_uid = rec->lsr_uid; body->oa.o_gid = rec->lsr_gid; body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID; /* old setattr record (prior 2.6.0) doesn't have 'valid' stored, * we assume that both UID and GID are valid in that case. */ if (rec->lsr_valid == 0) body->oa.o_valid |= (OBD_MD_FLUID | OBD_MD_FLGID); else body->oa.o_valid |= rec->lsr_valid; osp_sync_send_new_rpc(d, req); RETURN(1); } /** * Generate a request for unlink change. * * The function prepares a new RPC, initializes it with unlink(destroy) * specific bits and sends the RPC. The function is used to handle * llog_unlink_rec which were used in the older versions of Lustre. * Current version uses llog_unlink_rec64. * * \param[in] d OSP device * \param[in] llh llog handle where the record is stored * \param[in] h llog record * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_new_unlink_job(struct osp_device *d, struct llog_handle *llh, struct llog_rec_hdr *h) { struct llog_unlink_rec *rec = (struct llog_unlink_rec *)h; struct ptlrpc_request *req; struct ost_body *body; ENTRY; LASSERT(h->lrh_type == MDS_UNLINK_REC); req = osp_sync_new_job(d, llh, h, OST_DESTROY, &RQF_OST_DESTROY); if (IS_ERR(req)) RETURN(PTR_ERR(req)); body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY); LASSERT(body); ostid_set_seq(&body->oa.o_oi, rec->lur_oseq); ostid_set_id(&body->oa.o_oi, rec->lur_oid); body->oa.o_misc = rec->lur_count; body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID; if (rec->lur_count) body->oa.o_valid |= OBD_MD_FLOBJCOUNT; osp_sync_send_new_rpc(d, req); RETURN(1); } /** * Prepare OUT-based object destroy RPC. * * The function allocates a new RPC with OUT format. Then initializes the RPC * to contain OUT_DESTROY update against the object specified in the llog * record provided by the caller. * * \param[in] env LU environment provided by the caller * \param[in] osp OSP device * \param[in] llh llog handle where the record is stored * \param[in] h llog record * \param[out] reqp request prepared * * \retval 0 on success * \retval negative negated errno on error */ static int osp_prep_unlink_update_req(const struct lu_env *env, struct osp_device *osp, struct llog_handle *llh, struct llog_rec_hdr *h, struct ptlrpc_request **reqp) { struct llog_unlink64_rec *rec = (struct llog_unlink64_rec *)h; struct dt_update_request *update = NULL; struct ptlrpc_request *req; struct llog_cookie lcookie; const void *buf; __u16 size; int rc; ENTRY; update = dt_update_request_create(&osp->opd_dt_dev); if (IS_ERR(update)) RETURN(PTR_ERR(update)); /* This can only happens for unlink slave directory, so decrease * ref for ".." and "." */ rc = out_update_pack(env, &update->dur_buf, OUT_REF_DEL, &rec->lur_fid, 0, NULL, NULL, 0); if (rc != 0) GOTO(out, rc); rc = out_update_pack(env, &update->dur_buf, OUT_REF_DEL, &rec->lur_fid, 0, NULL, NULL, 0); if (rc != 0) GOTO(out, rc); lcookie.lgc_lgl = llh->lgh_id; lcookie.lgc_subsys = LLOG_MDS_OST_ORIG_CTXT; lcookie.lgc_index = h->lrh_index; size = sizeof(lcookie); buf = &lcookie; rc = out_update_pack(env, &update->dur_buf, OUT_DESTROY, &rec->lur_fid, 1, &size, &buf, 0); if (rc != 0) GOTO(out, rc); rc = out_prep_update_req(env, osp->opd_obd->u.cli.cl_import, update->dur_buf.ub_req, &req); if (rc != 0) GOTO(out, rc); INIT_LIST_HEAD(&req->rq_exp_list); req->rq_svc_thread = (void *)OSP_JOB_MAGIC; req->rq_interpret_reply = osp_sync_interpret; req->rq_commit_cb = osp_sync_request_commit_cb; req->rq_cb_data = osp; ptlrpc_request_set_replen(req); *reqp = req; out: if (update != NULL) dt_update_request_destroy(update); RETURN(rc); } /** * Generate a request for unlink change. * * The function prepares a new RPC, initializes it with unlink(destroy) * specific bits and sends the RPC. Depending on the target (MDT or OST) * two different protocols are used. For MDT we use OUT (basically OSD API * updates transferred via a network). For OST we still use the old * protocol (OBD?), originally for compatibility. Later we can start to * use OUT for OST as well, this will allow batching and better code * unification. * * \param[in] env LU environment provided by the caller * \param[in] d OSP device * \param[in] llh llog handle where the record is stored * \param[in] h llog record * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_new_unlink64_job(const struct lu_env *env, struct osp_device *d, struct llog_handle *llh, struct llog_rec_hdr *h) { struct llog_unlink64_rec *rec = (struct llog_unlink64_rec *)h; struct ptlrpc_request *req = NULL; struct ost_body *body; int rc; ENTRY; LASSERT(h->lrh_type == MDS_UNLINK64_REC); if (d->opd_connect_mdt) { rc = osp_prep_unlink_update_req(env, d, llh, h, &req); if (rc != 0) RETURN(rc); } else { req = osp_sync_new_job(d, llh, h, OST_DESTROY, &RQF_OST_DESTROY); if (IS_ERR(req)) RETURN(PTR_ERR(req)); body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY); if (body == NULL) RETURN(-EFAULT); rc = fid_to_ostid(&rec->lur_fid, &body->oa.o_oi); if (rc < 0) RETURN(rc); body->oa.o_misc = rec->lur_count; body->oa.o_valid = OBD_MD_FLGROUP | OBD_MD_FLID | OBD_MD_FLOBJCOUNT; } osp_sync_send_new_rpc(d, req); RETURN(1); } /** * Process llog records. * * This function is called to process the llog records committed locally. * In the recovery model used by OSP we can apply a change to a remote * target once corresponding transaction (like posix unlink) is committed * locally so can't revert. * Depending on the llog record type, a given handler is called that is * responsible for preparing and sending the RPC to apply the change. * Special record type LLOG_GEN_REC marking a reboot is cancelled right away. * * \param[in] env LU environment provided by the caller * \param[in] d OSP device * \param[in] llh llog handle where the record is stored * \param[in] rec llog record * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_process_record(const struct lu_env *env, struct osp_device *d, struct llog_handle *llh, struct llog_rec_hdr *rec) { struct llog_cookie cookie; int rc = 0; cookie.lgc_lgl = llh->lgh_id; cookie.lgc_subsys = LLOG_MDS_OST_ORIG_CTXT; cookie.lgc_index = rec->lrh_index; if (unlikely(rec->lrh_type == LLOG_GEN_REC)) { struct llog_gen_rec *gen = (struct llog_gen_rec *)rec; /* we're waiting for the record generated by this instance */ LASSERT(d->opd_syn_prev_done == 0); if (!memcmp(&d->opd_syn_generation, &gen->lgr_gen, sizeof(gen->lgr_gen))) { CDEBUG(D_HA, "processed all old entries\n"); d->opd_syn_prev_done = 1; } /* cancel any generation record */ rc = llog_cat_cancel_records(env, llh->u.phd.phd_cat_handle, 1, &cookie); return rc; } /* * now we prepare and fill requests to OST, put them on the queue * and fire after next commit callback */ /* notice we increment counters before sending RPC, to be consistent * in RPC interpret callback which may happen very quickly */ spin_lock(&d->opd_syn_lock); d->opd_syn_rpc_in_flight++; d->opd_syn_rpc_in_progress++; spin_unlock(&d->opd_syn_lock); switch (rec->lrh_type) { /* case MDS_UNLINK_REC is kept for compatibility */ case MDS_UNLINK_REC: rc = osp_sync_new_unlink_job(d, llh, rec); break; case MDS_UNLINK64_REC: rc = osp_sync_new_unlink64_job(env, d, llh, rec); break; case MDS_SETATTR64_REC: rc = osp_sync_new_setattr_job(d, llh, rec); break; default: CERROR("%s: unknown record type: %x\n", d->opd_obd->obd_name, rec->lrh_type); /* we should continue processing */ } /* rc > 0 means sync RPC being added to the queue */ if (likely(rc > 0)) { spin_lock(&d->opd_syn_lock); if (d->opd_syn_prev_done) { LASSERT(d->opd_syn_changes > 0); LASSERT(rec->lrh_id <= d->opd_syn_last_committed_id); /* * NOTE: it's possible to meet same id if * OST stores few stripes of same file */ if (rec->lrh_id > d->opd_syn_last_processed_id) { d->opd_syn_last_processed_id = rec->lrh_id; wake_up(&d->opd_syn_barrier_waitq); } d->opd_syn_changes--; } CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n", d->opd_obd->obd_name, d->opd_syn_rpc_in_flight, d->opd_syn_rpc_in_progress); spin_unlock(&d->opd_syn_lock); rc = 0; } else { spin_lock(&d->opd_syn_lock); d->opd_syn_rpc_in_flight--; d->opd_syn_rpc_in_progress--; spin_unlock(&d->opd_syn_lock); } CDEBUG(D_HA, "found record %x, %d, idx %u, id %u: %d\n", rec->lrh_type, rec->lrh_len, rec->lrh_index, rec->lrh_id, rc); return rc; } /** * Cancel llog records for the committed changes. * * The function walks through the list of the committed RPCs and cancels * corresponding llog records. see osp_sync_request_commit_cb() for the * details. * * \param[in] env LU environment provided by the caller * \param[in] d OSP device */ static void osp_sync_process_committed(const struct lu_env *env, struct osp_device *d) { struct obd_device *obd = d->opd_obd; struct obd_import *imp = obd->u.cli.cl_import; struct ost_body *body; struct ptlrpc_request *req, *tmp; struct llog_ctxt *ctxt; struct llog_handle *llh; struct list_head list; int rc, done = 0; ENTRY; if (list_empty(&d->opd_syn_committed_there)) return; /* * if current status is -ENOSPC (lack of free space on OST) * then we should poll OST immediately once object destroy * is committed. * notice: we do this upon commit as well because some backends * (like DMU) do not release space right away. */ if (d->opd_pre != NULL && unlikely(d->opd_pre_status == -ENOSPC)) osp_statfs_need_now(d); /* * now cancel them all * XXX: can we improve this using some batching? * with batch RPC that'll happen automatically? * XXX: can we store ctxt in lod_device and save few cycles ? */ ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT); LASSERT(ctxt); llh = ctxt->loc_handle; LASSERT(llh); INIT_LIST_HEAD(&list); spin_lock(&d->opd_syn_lock); list_splice(&d->opd_syn_committed_there, &list); INIT_LIST_HEAD(&d->opd_syn_committed_there); spin_unlock(&d->opd_syn_lock); list_for_each_entry_safe(req, tmp, &list, rq_exp_list) { struct llog_cookie *lcookie = NULL; LASSERT(req->rq_svc_thread == (void *) OSP_JOB_MAGIC); list_del_init(&req->rq_exp_list); if (d->opd_connect_mdt) { struct object_update_request *ureq; struct object_update *update; ureq = req_capsule_client_get(&req->rq_pill, &RMF_OUT_UPDATE); LASSERT(ureq != NULL && ureq->ourq_magic == UPDATE_REQUEST_MAGIC); /* 1st/2nd is for decref . and .., 3rd one is for * destroy, where the log cookie is stored. * See osp_prep_unlink_update_req */ update = object_update_request_get(ureq, 2, NULL); LASSERT(update != NULL); lcookie = object_update_param_get(update, 0, NULL); LASSERT(lcookie != NULL); } else { body = req_capsule_client_get(&req->rq_pill, &RMF_OST_BODY); LASSERT(body); lcookie = &body->oa.o_lcookie; } /* import can be closing, thus all commit cb's are * called we can check committness directly */ if (req->rq_transno <= imp->imp_peer_committed_transno) { rc = llog_cat_cancel_records(env, llh, 1, lcookie); if (rc) CERROR("%s: can't cancel record: %d\n", obd->obd_name, rc); } else { DEBUG_REQ(D_HA, req, "not committed"); } ptlrpc_req_finished(req); done++; } llog_ctxt_put(ctxt); LASSERT(d->opd_syn_rpc_in_progress >= done); spin_lock(&d->opd_syn_lock); d->opd_syn_rpc_in_progress -= done; spin_unlock(&d->opd_syn_lock); CDEBUG(D_OTHER, "%s: %d in flight, %d in progress\n", d->opd_obd->obd_name, d->opd_syn_rpc_in_flight, d->opd_syn_rpc_in_progress); osp_sync_check_for_work(d); /* wake up the thread if requested to stop: * it might be waiting for in-progress to complete */ if (unlikely(osp_sync_running(d) == 0)) wake_up(&d->opd_syn_waitq); EXIT; } /** * The core of the syncing mechanism. * * This is a callback called by the llog processing function. Essentially it * suspends llog processing until there is a record to process (it's supposed * to be committed locally). The function handles RPCs committed by the target * and cancels corresponding llog records. * * \param[in] env LU environment provided by the caller * \param[in] llh llog handle we're processing * \param[in] rec current llog record * \param[in] data callback data containing a pointer to the device * * \retval 0 to ask the caller (llog_process()) to continue * \retval LLOG_PROC_BREAK to ask the caller to break */ static int osp_sync_process_queues(const struct lu_env *env, struct llog_handle *llh, struct llog_rec_hdr *rec, void *data) { struct osp_device *d = data; int rc; do { struct l_wait_info lwi = { 0 }; if (!osp_sync_running(d)) { CDEBUG(D_HA, "stop llog processing\n"); return LLOG_PROC_BREAK; } /* process requests committed by OST */ osp_sync_process_committed(env, d); /* if we there are changes to be processed and we have * resources for this ... do now */ if (osp_sync_can_process_new(d, rec)) { if (llh == NULL) { /* ask llog for another record */ CDEBUG(D_HA, "%lu changes, %u in progress," " %u in flight\n", d->opd_syn_changes, d->opd_syn_rpc_in_progress, d->opd_syn_rpc_in_flight); return 0; } /* * try to send, in case of disconnection, suspend * processing till we can send this request */ do { rc = osp_sync_process_record(env, d, llh, rec); /* * XXX: probably different handling is needed * for some bugs, like immediate exit or if * OSP gets inactive */ if (rc) { CERROR("can't send: %d\n", rc); l_wait_event(d->opd_syn_waitq, !osp_sync_running(d) || osp_sync_has_work(d), &lwi); } } while (rc != 0 && osp_sync_running(d)); llh = NULL; rec = NULL; } if (d->opd_syn_last_processed_id == d->opd_syn_last_used_id) osp_sync_remove_from_tracker(d); l_wait_event(d->opd_syn_waitq, !osp_sync_running(d) || osp_sync_can_process_new(d, rec) || !list_empty(&d->opd_syn_committed_there), &lwi); } while (1); } /** * OSP sync thread. * * This thread runs llog_cat_process() scanner calling our callback * to process llog records. in the callback we implement tricky * state machine as we don't want to start scanning of the llog again * and again, also we don't want to process too many records and send * too many RPCs a time. so, depending on current load (num of changes * being synced to OST) the callback can suspend awaiting for some * new conditions, like syncs completed. * * In order to process llog records left by previous boots and to allow * llog_process_thread() to find something (otherwise it'd just exit * immediately) we add a special GENERATATION record on each boot. * * \param[in] _arg a pointer to thread's arguments * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_thread(void *_arg) { struct osp_device *d = _arg; struct ptlrpc_thread *thread = &d->opd_syn_thread; struct l_wait_info lwi = { 0 }; struct llog_ctxt *ctxt; struct obd_device *obd = d->opd_obd; struct llog_handle *llh; struct lu_env env; int rc, count; ENTRY; rc = lu_env_init(&env, LCT_LOCAL); if (rc) { CERROR("%s: can't initialize env: rc = %d\n", obd->obd_name, rc); RETURN(rc); } spin_lock(&d->opd_syn_lock); thread->t_flags = SVC_RUNNING; spin_unlock(&d->opd_syn_lock); wake_up(&thread->t_ctl_waitq); ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT); if (ctxt == NULL) { CERROR("can't get appropriate context\n"); GOTO(out, rc = -EINVAL); } llh = ctxt->loc_handle; if (llh == NULL) { CERROR("can't get llh\n"); llog_ctxt_put(ctxt); GOTO(out, rc = -EINVAL); } rc = llog_cat_process(&env, llh, osp_sync_process_queues, d, 0, 0); LASSERTF(rc == 0 || rc == LLOG_PROC_BREAK, "%lu changes, %u in progress, %u in flight: %d\n", d->opd_syn_changes, d->opd_syn_rpc_in_progress, d->opd_syn_rpc_in_flight, rc); /* we don't expect llog_process_thread() to exit till umount */ LASSERTF(thread->t_flags != SVC_RUNNING, "%lu changes, %u in progress, %u in flight\n", d->opd_syn_changes, d->opd_syn_rpc_in_progress, d->opd_syn_rpc_in_flight); /* wait till all the requests are completed */ count = 0; while (d->opd_syn_rpc_in_progress > 0) { osp_sync_process_committed(&env, d); lwi = LWI_TIMEOUT(cfs_time_seconds(5), NULL, NULL); rc = l_wait_event(d->opd_syn_waitq, d->opd_syn_rpc_in_progress == 0, &lwi); if (rc == -ETIMEDOUT) count++; LASSERTF(count < 10, "%s: %d %d %sempty\n", d->opd_obd->obd_name, d->opd_syn_rpc_in_progress, d->opd_syn_rpc_in_flight, list_empty(&d->opd_syn_committed_there) ? "" : "!"); } llog_cat_close(&env, llh); rc = llog_cleanup(&env, ctxt); if (rc) CERROR("can't cleanup llog: %d\n", rc); out: LASSERTF(d->opd_syn_rpc_in_progress == 0, "%s: %d %d %sempty\n", d->opd_obd->obd_name, d->opd_syn_rpc_in_progress, d->opd_syn_rpc_in_flight, list_empty(&d->opd_syn_committed_there) ? "" : "!"); thread->t_flags = SVC_STOPPED; wake_up(&thread->t_ctl_waitq); lu_env_fini(&env); RETURN(0); } /** * Initialize llog. * * Initializes the llog. Specific llog to be used depends on the type of the * target OSP represents (OST or MDT). The function adds appends a new llog * record to mark the place where the records associated with this boot * start. * * \param[in] env LU environment provided by the caller * \param[in] d OSP device * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_llog_init(const struct lu_env *env, struct osp_device *d) { struct osp_thread_info *osi = osp_env_info(env); struct lu_fid *fid = &osi->osi_fid; struct llog_handle *lgh = NULL; struct obd_device *obd = d->opd_obd; struct llog_ctxt *ctxt; int rc; ENTRY; LASSERT(obd); /* * open llog corresponding to our OST */ OBD_SET_CTXT_MAGIC(&obd->obd_lvfs_ctxt); obd->obd_lvfs_ctxt.dt = d->opd_storage; if (d->opd_connect_mdt) lu_local_obj_fid(fid, SLAVE_LLOG_CATALOGS_OID); else lu_local_obj_fid(fid, LLOG_CATALOGS_OID); rc = llog_osd_get_cat_list(env, d->opd_storage, d->opd_index, 1, &osi->osi_cid, fid); if (rc) { CERROR("%s: can't get id from catalogs: rc = %d\n", obd->obd_name, rc); RETURN(rc); } CDEBUG(D_INFO, "%s: Init llog for %d - catid "DOSTID":%x\n", obd->obd_name, d->opd_index, POSTID(&osi->osi_cid.lci_logid.lgl_oi), osi->osi_cid.lci_logid.lgl_ogen); rc = llog_setup(env, obd, &obd->obd_olg, LLOG_MDS_OST_ORIG_CTXT, obd, &osp_mds_ost_orig_logops); if (rc) RETURN(rc); ctxt = llog_get_context(obd, LLOG_MDS_OST_ORIG_CTXT); LASSERT(ctxt); if (likely(logid_id(&osi->osi_cid.lci_logid) != 0)) { rc = llog_open(env, ctxt, &lgh, &osi->osi_cid.lci_logid, NULL, LLOG_OPEN_EXISTS); /* re-create llog if it is missing */ if (rc == -ENOENT) logid_set_id(&osi->osi_cid.lci_logid, 0); else if (rc < 0) GOTO(out_cleanup, rc); } if (unlikely(logid_id(&osi->osi_cid.lci_logid) == 0)) { rc = llog_open_create(env, ctxt, &lgh, NULL, NULL); if (rc < 0) GOTO(out_cleanup, rc); osi->osi_cid.lci_logid = lgh->lgh_id; } LASSERT(lgh != NULL); ctxt->loc_handle = lgh; rc = llog_cat_init_and_process(env, lgh); if (rc) GOTO(out_close, rc); rc = llog_osd_put_cat_list(env, d->opd_storage, d->opd_index, 1, &osi->osi_cid, fid); if (rc) GOTO(out_close, rc); /* * put a mark in the llog till which we'll be processing * old records restless */ d->opd_syn_generation.mnt_cnt = cfs_time_current(); d->opd_syn_generation.conn_cnt = cfs_time_current(); osi->osi_hdr.lrh_type = LLOG_GEN_REC; osi->osi_hdr.lrh_len = sizeof(osi->osi_gen); memcpy(&osi->osi_gen.lgr_gen, &d->opd_syn_generation, sizeof(osi->osi_gen.lgr_gen)); rc = llog_cat_add(env, lgh, &osi->osi_gen.lgr_hdr, &osi->osi_cookie); if (rc < 0) GOTO(out_close, rc); llog_ctxt_put(ctxt); RETURN(0); out_close: llog_cat_close(env, lgh); out_cleanup: llog_cleanup(env, ctxt); RETURN(rc); } /** * Cleanup llog used for syncing. * * Closes and cleanups the llog. The function is called when the device is * shutting down. * * \param[in] env LU environment provided by the caller * \param[in] d OSP device */ static void osp_sync_llog_fini(const struct lu_env *env, struct osp_device *d) { struct llog_ctxt *ctxt; ctxt = llog_get_context(d->opd_obd, LLOG_MDS_OST_ORIG_CTXT); if (ctxt != NULL) llog_cat_close(env, ctxt->loc_handle); llog_cleanup(env, ctxt); } /** * Initialization of the sync component of OSP. * * Initializes the llog and starts a new thread to handle the changes to * the remote target (OST or MDT). * * \param[in] env LU environment provided by the caller * \param[in] d OSP device * * \retval 0 on success * \retval negative negated errno on error */ int osp_sync_init(const struct lu_env *env, struct osp_device *d) { struct l_wait_info lwi = { 0 }; struct task_struct *task; int rc; ENTRY; rc = osp_sync_id_traction_init(d); if (rc) RETURN(rc); /* * initialize llog storing changes */ rc = osp_sync_llog_init(env, d); if (rc) { CERROR("%s: can't initialize llog: rc = %d\n", d->opd_obd->obd_name, rc); GOTO(err_id, rc); } /* * Start synchronization thread */ d->opd_syn_max_rpc_in_flight = OSP_MAX_IN_FLIGHT; d->opd_syn_max_rpc_in_progress = OSP_MAX_IN_PROGRESS; spin_lock_init(&d->opd_syn_lock); init_waitqueue_head(&d->opd_syn_waitq); init_waitqueue_head(&d->opd_syn_barrier_waitq); init_waitqueue_head(&d->opd_syn_thread.t_ctl_waitq); INIT_LIST_HEAD(&d->opd_syn_committed_there); task = kthread_run(osp_sync_thread, d, "osp-syn-%u-%u", d->opd_index, d->opd_group); if (IS_ERR(task)) { rc = PTR_ERR(task); CERROR("%s: cannot start sync thread: rc = %d\n", d->opd_obd->obd_name, rc); GOTO(err_llog, rc); } l_wait_event(d->opd_syn_thread.t_ctl_waitq, osp_sync_running(d) || osp_sync_stopped(d), &lwi); RETURN(0); err_llog: osp_sync_llog_fini(env, d); err_id: osp_sync_id_traction_fini(d); return rc; } /** * Stop the syncing thread. * * Asks the syncing thread to stop and wait until it's stopped. * * \param[in] d OSP device * * \retval 0 */ int osp_sync_fini(struct osp_device *d) { struct ptlrpc_thread *thread = &d->opd_syn_thread; ENTRY; thread->t_flags = SVC_STOPPING; wake_up(&d->opd_syn_waitq); wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_STOPPED); /* * unregister transaction callbacks only when sync thread * has finished operations with llog */ osp_sync_id_traction_fini(d); RETURN(0); } static DEFINE_MUTEX(osp_id_tracker_sem); static struct list_head osp_id_tracker_list = LIST_HEAD_INIT(osp_id_tracker_list); /** * OSD commit callback. * * The function is used as a local OSD commit callback to track the highest * committed llog record id. see osp_sync_id_traction_init() for the details. * * \param[in] th local transaction handle committed * \param[in] cookie commit callback data (our private structure) */ static void osp_sync_tracker_commit_cb(struct thandle *th, void *cookie) { struct osp_id_tracker *tr = cookie; struct osp_device *d; struct osp_txn_info *txn; LASSERT(tr); txn = osp_txn_info(&th->th_ctx); if (txn == NULL || txn->oti_current_id < tr->otr_committed_id) return; spin_lock(&tr->otr_lock); if (likely(txn->oti_current_id > tr->otr_committed_id)) { CDEBUG(D_OTHER, "committed: %u -> %u\n", tr->otr_committed_id, txn->oti_current_id); tr->otr_committed_id = txn->oti_current_id; list_for_each_entry(d, &tr->otr_wakeup_list, opd_syn_ontrack) { d->opd_syn_last_committed_id = tr->otr_committed_id; wake_up(&d->opd_syn_waitq); } } spin_unlock(&tr->otr_lock); } /** * Initialize commit tracking mechanism. * * Some setups may have thousands of OSTs and each will be represented by OSP. * Meaning order of magnitute many more changes to apply every second. In order * to keep the number of commit callbacks low this mechanism was introduced. * The mechanism is very similar to transno used by MDT service: it's an single * ID stream which can be assigned by any OSP to its llog records. The tricky * part is that ID is stored in per-transaction data and re-used by all the OSPs * involved in that transaction. Then all these OSPs are woken up utilizing a single OSD commit callback. * * The function initializes the data used by the tracker described above. * A singler tracker per OSD device is created. * * \param[in] d OSP device * * \retval 0 on success * \retval negative negated errno on error */ static int osp_sync_id_traction_init(struct osp_device *d) { struct osp_id_tracker *tr, *found = NULL; int rc = 0; LASSERT(d); LASSERT(d->opd_storage); LASSERT(d->opd_syn_tracker == NULL); INIT_LIST_HEAD(&d->opd_syn_ontrack); mutex_lock(&osp_id_tracker_sem); list_for_each_entry(tr, &osp_id_tracker_list, otr_list) { if (tr->otr_dev == d->opd_storage) { LASSERT(atomic_read(&tr->otr_refcount)); atomic_inc(&tr->otr_refcount); d->opd_syn_tracker = tr; found = tr; break; } } if (found == NULL) { rc = -ENOMEM; OBD_ALLOC_PTR(tr); if (tr) { d->opd_syn_tracker = tr; spin_lock_init(&tr->otr_lock); tr->otr_dev = d->opd_storage; tr->otr_next_id = 1; tr->otr_committed_id = 0; atomic_set(&tr->otr_refcount, 1); INIT_LIST_HEAD(&tr->otr_wakeup_list); list_add(&tr->otr_list, &osp_id_tracker_list); tr->otr_tx_cb.dtc_txn_commit = osp_sync_tracker_commit_cb; tr->otr_tx_cb.dtc_cookie = tr; tr->otr_tx_cb.dtc_tag = LCT_MD_THREAD; dt_txn_callback_add(d->opd_storage, &tr->otr_tx_cb); rc = 0; } } mutex_unlock(&osp_id_tracker_sem); return rc; } /** * Release commit tracker. * * Decrease a refcounter on the tracker used by the given OSP device \a d. * If no more users left, then the tracker is released. * * \param[in] d OSP device */ static void osp_sync_id_traction_fini(struct osp_device *d) { struct osp_id_tracker *tr; ENTRY; LASSERT(d); tr = d->opd_syn_tracker; if (tr == NULL) { EXIT; return; } osp_sync_remove_from_tracker(d); mutex_lock(&osp_id_tracker_sem); if (atomic_dec_and_test(&tr->otr_refcount)) { dt_txn_callback_del(d->opd_storage, &tr->otr_tx_cb); LASSERT(list_empty(&tr->otr_wakeup_list)); list_del(&tr->otr_list); OBD_FREE_PTR(tr); d->opd_syn_tracker = NULL; } mutex_unlock(&osp_id_tracker_sem); EXIT; } /** * Generate a new ID on a tracker. * * Generates a new ID using the tracker associated with the given OSP device * \a d, if the given ID \a id is non-zero. Unconditially adds OSP device to * the wakeup list, so OSP won't miss when a transaction using the ID is * committed. Notice ID is 32bit, but llog doesn't support >2^32 records anyway. * * \param[in] d OSP device * \param[in] id 0 or ID generated previously * * \retval ID the caller should use */ static __u32 osp_sync_id_get(struct osp_device *d, __u32 id) { struct osp_id_tracker *tr; tr = d->opd_syn_tracker; LASSERT(tr); /* XXX: we can improve this introducing per-cpu preallocated ids? */ spin_lock(&tr->otr_lock); if (unlikely(tr->otr_next_id <= d->opd_syn_last_used_id)) { spin_unlock(&tr->otr_lock); CERROR("%s: next %u, last synced %lu\n", d->opd_obd->obd_name, tr->otr_next_id, d->opd_syn_last_used_id); LBUG(); } if (id == 0) id = tr->otr_next_id++; if (id > d->opd_syn_last_used_id) d->opd_syn_last_used_id = id; if (list_empty(&d->opd_syn_ontrack)) list_add(&d->opd_syn_ontrack, &tr->otr_wakeup_list); spin_unlock(&tr->otr_lock); CDEBUG(D_OTHER, "new id %u\n", (unsigned) id); return id; } /** * Stop to propagate commit status to OSP. * * If the OSP does not have any llog records she's waiting to commit, then * it is possible to unsubscribe from wakeups from the tracking using this * method. * * \param[in] d OSP device not willing to wakeup */ static void osp_sync_remove_from_tracker(struct osp_device *d) { struct osp_id_tracker *tr; tr = d->opd_syn_tracker; LASSERT(tr); if (list_empty(&d->opd_syn_ontrack)) return; spin_lock(&tr->otr_lock); list_del_init(&d->opd_syn_ontrack); spin_unlock(&tr->otr_lock); }