4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
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12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 * included in the COPYING file that accompanied this code.
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18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Copyright (c) 2011 Intel Corporation
25 * Copyright 2012 Xyratex Technology Limited
30 * Network Request Scheduler (NRS)
32 * Allows to reorder the handling of RPCs at servers.
34 * Author: Liang Zhen <liang@whamcloud.com>
35 * Author: Nikitas Angelinas <nikitas_angelinas@xyratex.com>
42 #define DEBUG_SUBSYSTEM S_RPC
43 #include <obd_support.h>
44 #include <obd_class.h>
45 #include <lustre_net.h>
46 #include <lprocfs_status.h>
47 #include <libcfs/libcfs.h>
48 #include "ptlrpc_internal.h"
53 struct nrs_core nrs_core;
55 static int nrs_policy_init(struct ptlrpc_nrs_policy *policy)
57 return policy->pol_desc->pd_ops->op_policy_init != NULL ?
58 policy->pol_desc->pd_ops->op_policy_init(policy) : 0;
61 static void nrs_policy_fini(struct ptlrpc_nrs_policy *policy)
63 LASSERT(policy->pol_ref == 0);
64 LASSERT(policy->pol_req_queued == 0);
66 if (policy->pol_desc->pd_ops->op_policy_fini != NULL)
67 policy->pol_desc->pd_ops->op_policy_fini(policy);
70 static int nrs_policy_ctl_locked(struct ptlrpc_nrs_policy *policy,
71 enum ptlrpc_nrs_ctl opc, void *arg)
74 * The policy may be stopped, but the lprocfs files and
75 * ptlrpc_nrs_policy instances remain present until unregistration time.
76 * Do not perform the ctl operation if the policy is stopped, as
77 * policy->pol_private will be NULL in such a case.
79 if (policy->pol_state == NRS_POL_STATE_STOPPED)
82 RETURN(policy->pol_desc->pd_ops->op_policy_ctl != NULL ?
83 policy->pol_desc->pd_ops->op_policy_ctl(policy, opc, arg) :
87 static void nrs_policy_stop0(struct ptlrpc_nrs_policy *policy)
89 struct ptlrpc_nrs *nrs = policy->pol_nrs;
92 if (policy->pol_desc->pd_ops->op_policy_stop != NULL) {
93 spin_unlock(&nrs->nrs_lock);
95 policy->pol_desc->pd_ops->op_policy_stop(policy);
97 spin_lock(&nrs->nrs_lock);
100 LASSERT(list_empty(&policy->pol_list_queued));
101 LASSERT(policy->pol_req_queued == 0 &&
102 policy->pol_req_started == 0);
104 policy->pol_private = NULL;
106 policy->pol_state = NRS_POL_STATE_STOPPED;
108 if (atomic_dec_and_test(&policy->pol_desc->pd_refs))
109 module_put(policy->pol_desc->pd_owner);
114 static int nrs_policy_stop_locked(struct ptlrpc_nrs_policy *policy)
116 struct ptlrpc_nrs *nrs = policy->pol_nrs;
119 if (nrs->nrs_policy_fallback == policy && !nrs->nrs_stopping)
122 if (policy->pol_state == NRS_POL_STATE_STARTING)
125 /* In progress or already stopped */
126 if (policy->pol_state != NRS_POL_STATE_STARTED)
129 policy->pol_state = NRS_POL_STATE_STOPPING;
131 /* Immediately make it invisible */
132 if (nrs->nrs_policy_primary == policy) {
133 nrs->nrs_policy_primary = NULL;
136 LASSERT(nrs->nrs_policy_fallback == policy);
137 nrs->nrs_policy_fallback = NULL;
140 /* I have the only refcount */
141 if (policy->pol_ref == 1)
142 nrs_policy_stop0(policy);
148 * Transitions the \a nrs NRS head's primary policy to
149 * ptlrpc_nrs_pol_state::NRS_POL_STATE_STOPPING and if the policy has no
150 * pending usage references, to ptlrpc_nrs_pol_state::NRS_POL_STATE_STOPPED.
152 * \param[in] nrs the NRS head to carry out this operation on
154 static void nrs_policy_stop_primary(struct ptlrpc_nrs *nrs)
156 struct ptlrpc_nrs_policy *tmp = nrs->nrs_policy_primary;
161 * XXX: This should really be RETURN_EXIT, but the latter does
162 * not currently print anything out, and possibly should be
169 nrs->nrs_policy_primary = NULL;
171 LASSERT(tmp->pol_state == NRS_POL_STATE_STARTED);
172 tmp->pol_state = NRS_POL_STATE_STOPPING;
174 if (tmp->pol_ref == 0)
175 nrs_policy_stop0(tmp);
180 * Transitions a policy across the ptlrpc_nrs_pol_state range of values, in
181 * response to an lprocfs command to start a policy.
183 * If a primary policy different to the current one is specified, this function
184 * will transition the new policy to the
185 * ptlrpc_nrs_pol_state::NRS_POL_STATE_STARTING and then to
186 * ptlrpc_nrs_pol_state::NRS_POL_STATE_STARTED, and will then transition
187 * the old primary policy (if there is one) to
188 * ptlrpc_nrs_pol_state::NRS_POL_STATE_STOPPING, and if there are no outstanding
189 * references on the policy to ptlrpc_nrs_pol_stae::NRS_POL_STATE_STOPPED.
191 * If the fallback policy is specified, this is taken to indicate an instruction
192 * to stop the current primary policy, without substituting it with another
193 * primary policy, so the primary policy (if any) is transitioned to
194 * ptlrpc_nrs_pol_state::NRS_POL_STATE_STOPPING, and if there are no outstanding
195 * references on the policy to ptlrpc_nrs_pol_stae::NRS_POL_STATE_STOPPED. In
196 * this case, the fallback policy is only left active in the NRS head.
198 static int nrs_policy_start_locked(struct ptlrpc_nrs_policy *policy, char *arg)
200 struct ptlrpc_nrs *nrs = policy->pol_nrs;
205 * Don't allow multiple starting which is too complex, and has no real
208 if (nrs->nrs_policy_starting)
211 LASSERT(policy->pol_state != NRS_POL_STATE_STARTING);
213 if (policy->pol_state == NRS_POL_STATE_STOPPING)
216 if (policy->pol_flags & PTLRPC_NRS_FL_FALLBACK) {
218 * This is for cases in which the user sets the policy to the
219 * fallback policy (currently fifo for all services); i.e. the
220 * user is resetting the policy to the default; so we stop the
221 * primary policy, if any.
223 if (policy == nrs->nrs_policy_fallback) {
224 nrs_policy_stop_primary(nrs);
229 * If we reach here, we must be setting up the fallback policy
230 * at service startup time, and only a single policy with the
231 * nrs_policy_flags::PTLRPC_NRS_FL_FALLBACK flag set can
232 * register with NRS core.
234 LASSERT(nrs->nrs_policy_fallback == NULL);
237 * Shouldn't start primary policy if w/o fallback policy.
239 if (nrs->nrs_policy_fallback == NULL)
242 if (policy->pol_state == NRS_POL_STATE_STARTED)
247 * Increase the module usage count for policies registering from other
250 if (atomic_inc_return(&policy->pol_desc->pd_refs) == 1 &&
251 !try_module_get(policy->pol_desc->pd_owner)) {
252 atomic_dec(&policy->pol_desc->pd_refs);
253 CERROR("NRS: cannot get module for policy %s; is it alive?\n",
254 policy->pol_desc->pd_name);
259 * Serialize policy starting across the NRS head
261 nrs->nrs_policy_starting = 1;
263 policy->pol_state = NRS_POL_STATE_STARTING;
265 if (policy->pol_desc->pd_ops->op_policy_start) {
266 spin_unlock(&nrs->nrs_lock);
268 rc = policy->pol_desc->pd_ops->op_policy_start(policy, arg);
270 spin_lock(&nrs->nrs_lock);
272 if (atomic_dec_and_test(&policy->pol_desc->pd_refs))
273 module_put(policy->pol_desc->pd_owner);
275 policy->pol_state = NRS_POL_STATE_STOPPED;
280 policy->pol_state = NRS_POL_STATE_STARTED;
282 if (policy->pol_flags & PTLRPC_NRS_FL_FALLBACK) {
284 * This path is only used at PTLRPC service setup time.
286 nrs->nrs_policy_fallback = policy;
289 * Try to stop the current primary policy if there is one.
291 nrs_policy_stop_primary(nrs);
294 * And set the newly-started policy as the primary one.
296 nrs->nrs_policy_primary = policy;
300 nrs->nrs_policy_starting = 0;
306 * Increases the policy's usage reference count.
308 static inline void nrs_policy_get_locked(struct ptlrpc_nrs_policy *policy)
314 * Decreases the policy's usage reference count, and stops the policy in case it
315 * was already stopping and have no more outstanding usage references (which
316 * indicates it has no more queued or started requests, and can be safely
319 static void nrs_policy_put_locked(struct ptlrpc_nrs_policy *policy)
321 LASSERT(policy->pol_ref > 0);
324 if (unlikely(policy->pol_ref == 0 &&
325 policy->pol_state == NRS_POL_STATE_STOPPING))
326 nrs_policy_stop0(policy);
329 static void nrs_policy_put(struct ptlrpc_nrs_policy *policy)
331 spin_lock(&policy->pol_nrs->nrs_lock);
332 nrs_policy_put_locked(policy);
333 spin_unlock(&policy->pol_nrs->nrs_lock);
337 * Find and return a policy by name.
339 static struct ptlrpc_nrs_policy * nrs_policy_find_locked(struct ptlrpc_nrs *nrs,
342 struct ptlrpc_nrs_policy *tmp;
344 list_for_each_entry(tmp, &nrs->nrs_policy_list, pol_list) {
345 if (strncmp(tmp->pol_desc->pd_name, name,
346 NRS_POL_NAME_MAX) == 0) {
347 nrs_policy_get_locked(tmp);
355 * Release references for the resource hierarchy moving upwards towards the
356 * policy instance resource.
358 static void nrs_resource_put(struct ptlrpc_nrs_resource *res)
360 struct ptlrpc_nrs_policy *policy = res->res_policy;
362 if (policy->pol_desc->pd_ops->op_res_put != NULL) {
363 struct ptlrpc_nrs_resource *parent;
365 for (; res != NULL; res = parent) {
366 parent = res->res_parent;
367 policy->pol_desc->pd_ops->op_res_put(policy, res);
373 * Obtains references for each resource in the resource hierarchy for request
374 * \a nrq if it is to be handled by \a policy.
376 * \param[in] policy the policy
377 * \param[in] nrq the request
378 * \param[in] moving_req denotes whether this is a call to the function by
379 * ldlm_lock_reorder_req(), in order to move \a nrq to
380 * the high-priority NRS head; we should not sleep when
383 * \retval NULL resource hierarchy references not obtained
384 * \retval valid-pointer the bottom level of the resource hierarchy
386 * \see ptlrpc_nrs_pol_ops::op_res_get()
389 struct ptlrpc_nrs_resource * nrs_resource_get(struct ptlrpc_nrs_policy *policy,
390 struct ptlrpc_nrs_request *nrq,
394 * Set to NULL to traverse the resource hierarchy from the top.
396 struct ptlrpc_nrs_resource *res = NULL;
397 struct ptlrpc_nrs_resource *tmp = NULL;
401 rc = policy->pol_desc->pd_ops->op_res_get(policy, nrq, res,
405 nrs_resource_put(res);
409 LASSERT(tmp != NULL);
410 tmp->res_parent = res;
411 tmp->res_policy = policy;
415 * Return once we have obtained a reference to the bottom level
416 * of the resource hierarchy.
424 * Obtains resources for the resource hierarchies and policy references for
425 * the fallback and current primary policy (if any), that will later be used
426 * to handle request \a nrq.
428 * \param[in] nrs the NRS head instance that will be handling request \a nrq.
429 * \param[in] nrq the request that is being handled.
430 * \param[out] resp the array where references to the resource hierarchy are
432 * \param[in] moving_req is set when obtaining resources while moving a
433 * request from a policy on the regular NRS head to a
434 * policy on the HP NRS head (via
435 * ldlm_lock_reorder_req()). It signifies that
436 * allocations to get resources should be atomic; for
437 * a full explanation, see comment in
438 * ptlrpc_nrs_pol_ops::op_res_get().
440 static void nrs_resource_get_safe(struct ptlrpc_nrs *nrs,
441 struct ptlrpc_nrs_request *nrq,
442 struct ptlrpc_nrs_resource **resp,
445 struct ptlrpc_nrs_policy *primary = NULL;
446 struct ptlrpc_nrs_policy *fallback = NULL;
448 memset(resp, 0, sizeof(resp[0]) * NRS_RES_MAX);
451 * Obtain policy references.
453 spin_lock(&nrs->nrs_lock);
455 fallback = nrs->nrs_policy_fallback;
456 nrs_policy_get_locked(fallback);
458 primary = nrs->nrs_policy_primary;
460 nrs_policy_get_locked(primary);
462 spin_unlock(&nrs->nrs_lock);
465 * Obtain resource hierarchy references.
467 resp[NRS_RES_FALLBACK] = nrs_resource_get(fallback, nrq, moving_req);
468 LASSERT(resp[NRS_RES_FALLBACK] != NULL);
470 if (primary != NULL) {
471 resp[NRS_RES_PRIMARY] = nrs_resource_get(primary, nrq,
474 * A primary policy may exist which may not wish to serve a
475 * particular request for different reasons; release the
476 * reference on the policy as it will not be used for this
479 if (resp[NRS_RES_PRIMARY] == NULL)
480 nrs_policy_put(primary);
485 * Releases references to resource hierarchies and policies, because they are no
486 * longer required; used when request handling has been completed, or the
487 * request is moving to the high priority NRS head.
489 * \param resp the resource hierarchy that is being released
491 * \see ptlrpcnrs_req_hp_move()
492 * \see ptlrpc_nrs_req_finalize()
494 static void nrs_resource_put_safe(struct ptlrpc_nrs_resource **resp)
496 struct ptlrpc_nrs_policy *pols[NRS_RES_MAX];
497 struct ptlrpc_nrs *nrs = NULL;
500 for (i = 0; i < NRS_RES_MAX; i++) {
501 if (resp[i] != NULL) {
502 pols[i] = resp[i]->res_policy;
503 nrs_resource_put(resp[i]);
510 for (i = 0; i < NRS_RES_MAX; i++) {
515 nrs = pols[i]->pol_nrs;
516 spin_lock(&nrs->nrs_lock);
518 nrs_policy_put_locked(pols[i]);
522 spin_unlock(&nrs->nrs_lock);
526 * Obtains an NRS request from \a policy for handling or examination; the
527 * request should be removed in the 'handling' case.
529 * Calling into this function implies we already know the policy has a request
530 * waiting to be handled.
532 * \param[in] policy the policy from which a request
533 * \param[in] peek when set, signifies that we just want to examine the
534 * request, and not handle it, so the request is not removed
536 * \param[in] force when set, it will force a policy to return a request if it
539 * \retval the NRS request to be handled
542 struct ptlrpc_nrs_request * nrs_request_get(struct ptlrpc_nrs_policy *policy,
543 bool peek, bool force)
545 struct ptlrpc_nrs_request *nrq;
547 LASSERT(policy->pol_req_queued > 0);
549 nrq = policy->pol_desc->pd_ops->op_req_get(policy, peek, force);
551 LASSERT(ergo(nrq != NULL, nrs_request_policy(nrq) == policy));
557 * Enqueues request \a nrq for later handling, via one one the policies for
558 * which resources where earlier obtained via nrs_resource_get_safe(). The
559 * function attempts to enqueue the request first on the primary policy
560 * (if any), since this is the preferred choice.
562 * \param nrq the request being enqueued
564 * \see nrs_resource_get_safe()
566 static inline void nrs_request_enqueue(struct ptlrpc_nrs_request *nrq)
568 struct ptlrpc_nrs_policy *policy;
573 * Try in descending order, because the primary policy (if any) is
574 * the preferred choice.
576 for (i = NRS_RES_MAX - 1; i >= 0; i--) {
577 if (nrq->nr_res_ptrs[i] == NULL)
581 policy = nrq->nr_res_ptrs[i]->res_policy;
583 rc = policy->pol_desc->pd_ops->op_req_enqueue(policy, nrq);
585 policy->pol_nrs->nrs_req_queued++;
586 policy->pol_req_queued++;
591 * Should never get here, as at least the primary policy's
592 * ptlrpc_nrs_pol_ops::op_req_enqueue() implementation should always
599 * Called when a request has been handled
601 * \param[in] nrs the request that has been handled; can be used for
602 * job/resource control.
604 * \see ptlrpc_nrs_req_stop_nolock()
606 static inline void nrs_request_stop(struct ptlrpc_nrs_request *nrq)
608 struct ptlrpc_nrs_policy *policy = nrs_request_policy(nrq);
610 if (policy->pol_desc->pd_ops->op_req_stop)
611 policy->pol_desc->pd_ops->op_req_stop(policy, nrq);
613 LASSERT(policy->pol_nrs->nrs_req_started > 0);
614 LASSERT(policy->pol_req_started > 0);
616 policy->pol_nrs->nrs_req_started--;
617 policy->pol_req_started--;
621 * Handler for operations that can be carried out on policies.
623 * Handles opcodes that are common to all policy types within NRS core, and
624 * passes any unknown opcodes to the policy-specific control function.
626 * \param[in] nrs the NRS head this policy belongs to.
627 * \param[in] name the human-readable policy name; should be the same as
628 * ptlrpc_nrs_pol_desc::pd_name.
629 * \param[in] opc the opcode of the operation being carried out.
630 * \param[in,out] arg can be used to pass information in and out between when
631 * carrying an operation; usually data that is private to
632 * the policy at some level, or generic policy status
635 * \retval -ve error condition
636 * \retval 0 operation was carried out successfully
638 static int nrs_policy_ctl(struct ptlrpc_nrs *nrs, char *name,
639 enum ptlrpc_nrs_ctl opc, void *arg)
641 struct ptlrpc_nrs_policy *policy;
645 spin_lock(&nrs->nrs_lock);
647 policy = nrs_policy_find_locked(nrs, name);
649 GOTO(out, rc = -ENOENT);
653 * Unknown opcode, pass it down to the policy-specific control
654 * function for handling.
657 rc = nrs_policy_ctl_locked(policy, opc, arg);
663 case PTLRPC_NRS_CTL_START:
664 rc = nrs_policy_start_locked(policy, arg);
669 nrs_policy_put_locked(policy);
671 spin_unlock(&nrs->nrs_lock);
677 * Unregisters a policy by name.
679 * \param[in] nrs the NRS head this policy belongs to.
680 * \param[in] name the human-readable policy name; should be the same as
681 * ptlrpc_nrs_pol_desc::pd_name
686 static int nrs_policy_unregister(struct ptlrpc_nrs *nrs, char *name)
688 struct ptlrpc_nrs_policy *policy = NULL;
691 spin_lock(&nrs->nrs_lock);
693 policy = nrs_policy_find_locked(nrs, name);
694 if (policy == NULL) {
695 spin_unlock(&nrs->nrs_lock);
697 CERROR("Can't find NRS policy %s\n", name);
701 if (policy->pol_ref > 1) {
702 CERROR("Policy %s is busy with %d references\n", name,
703 (int)policy->pol_ref);
704 nrs_policy_put_locked(policy);
706 spin_unlock(&nrs->nrs_lock);
710 LASSERT(policy->pol_req_queued == 0);
711 LASSERT(policy->pol_req_started == 0);
713 if (policy->pol_state != NRS_POL_STATE_STOPPED) {
714 nrs_policy_stop_locked(policy);
715 LASSERT(policy->pol_state == NRS_POL_STATE_STOPPED);
718 list_del(&policy->pol_list);
721 nrs_policy_put_locked(policy);
723 spin_unlock(&nrs->nrs_lock);
725 nrs_policy_fini(policy);
727 LASSERT(policy->pol_private == NULL);
728 OBD_FREE_PTR(policy);
734 * Register a policy from \policy descriptor \a desc with NRS head \a nrs.
736 * \param[in] nrs the NRS head on which the policy will be registered.
737 * \param[in] desc the policy descriptor from which the information will be
738 * obtained to register the policy.
743 static int nrs_policy_register(struct ptlrpc_nrs *nrs,
744 struct ptlrpc_nrs_pol_desc *desc)
746 struct ptlrpc_nrs_policy *policy;
747 struct ptlrpc_nrs_policy *tmp;
748 struct ptlrpc_service_part *svcpt = nrs->nrs_svcpt;
752 LASSERT(svcpt != NULL);
753 LASSERT(desc->pd_ops != NULL);
754 LASSERT(desc->pd_ops->op_res_get != NULL);
755 LASSERT(desc->pd_ops->op_req_get != NULL);
756 LASSERT(desc->pd_ops->op_req_enqueue != NULL);
757 LASSERT(desc->pd_ops->op_req_dequeue != NULL);
758 LASSERT(desc->pd_compat != NULL);
760 OBD_CPT_ALLOC_GFP(policy, svcpt->scp_service->srv_cptable,
761 svcpt->scp_cpt, sizeof(*policy), GFP_NOFS);
765 policy->pol_nrs = nrs;
766 policy->pol_desc = desc;
767 policy->pol_state = NRS_POL_STATE_STOPPED;
768 policy->pol_flags = desc->pd_flags;
770 INIT_LIST_HEAD(&policy->pol_list);
771 INIT_LIST_HEAD(&policy->pol_list_queued);
773 rc = nrs_policy_init(policy);
775 OBD_FREE_PTR(policy);
779 spin_lock(&nrs->nrs_lock);
781 tmp = nrs_policy_find_locked(nrs, policy->pol_desc->pd_name);
783 CERROR("NRS policy %s has been registered, can't register it "
784 "for %s\n", policy->pol_desc->pd_name,
785 svcpt->scp_service->srv_name);
786 nrs_policy_put_locked(tmp);
788 spin_unlock(&nrs->nrs_lock);
789 nrs_policy_fini(policy);
790 OBD_FREE_PTR(policy);
795 list_add_tail(&policy->pol_list, &nrs->nrs_policy_list);
798 if (policy->pol_flags & PTLRPC_NRS_FL_REG_START)
799 rc = nrs_policy_start_locked(policy, NULL);
801 spin_unlock(&nrs->nrs_lock);
804 (void) nrs_policy_unregister(nrs, policy->pol_desc->pd_name);
810 * Enqueue request \a req using one of the policies its resources are referring
813 * \param[in] req the request to enqueue.
815 static void ptlrpc_nrs_req_add_nolock(struct ptlrpc_request *req)
817 struct ptlrpc_nrs_policy *policy;
819 LASSERT(req->rq_nrq.nr_initialized);
820 LASSERT(!req->rq_nrq.nr_enqueued);
822 nrs_request_enqueue(&req->rq_nrq);
823 req->rq_nrq.nr_enqueued = 1;
825 policy = nrs_request_policy(&req->rq_nrq);
827 * Add the policy to the NRS head's list of policies with enqueued
828 * requests, if it has not been added there.
830 if (unlikely(list_empty(&policy->pol_list_queued)))
831 list_add_tail(&policy->pol_list_queued,
832 &policy->pol_nrs->nrs_policy_queued);
836 * Enqueue a request on the high priority NRS head.
838 * \param req the request to enqueue.
840 static void ptlrpc_nrs_hpreq_add_nolock(struct ptlrpc_request *req)
842 int opc = lustre_msg_get_opc(req->rq_reqmsg);
845 spin_lock(&req->rq_lock);
847 ptlrpc_nrs_req_add_nolock(req);
849 DEBUG_REQ(D_NET, req, "high priority req");
850 spin_unlock(&req->rq_lock);
855 * Returns a boolean predicate indicating whether the policy described by
856 * \a desc is adequate for use with service \a svc.
858 * \param[in] svc the service
859 * \param[in] desc the policy descriptor
861 * \retval false the policy is not compatible with the service
862 * \retval true the policy is compatible with the service
864 static inline bool nrs_policy_compatible(const struct ptlrpc_service *svc,
865 const struct ptlrpc_nrs_pol_desc *desc)
867 return desc->pd_compat(svc, desc);
871 * Registers all compatible policies in nrs_core.nrs_policies, for NRS head
874 * \param[in] nrs the NRS head
879 * \pre mutex_is_locked(&nrs_core.nrs_mutex)
881 * \see ptlrpc_service_nrs_setup()
883 static int nrs_register_policies_locked(struct ptlrpc_nrs *nrs)
885 struct ptlrpc_nrs_pol_desc *desc;
886 /* for convenience */
887 struct ptlrpc_service_part *svcpt = nrs->nrs_svcpt;
888 struct ptlrpc_service *svc = svcpt->scp_service;
892 LASSERT(mutex_is_locked(&nrs_core.nrs_mutex));
894 list_for_each_entry(desc, &nrs_core.nrs_policies, pd_list) {
895 if (nrs_policy_compatible(svc, desc)) {
896 rc = nrs_policy_register(nrs, desc);
898 CERROR("Failed to register NRS policy %s for "
899 "partition %d of service %s: %d\n",
900 desc->pd_name, svcpt->scp_cpt,
903 * Fail registration if any of the policies'
904 * registration fails.
915 * Initializes NRS head \a nrs of service partition \a svcpt, and registers all
916 * compatible policies in NRS core, with the NRS head.
918 * \param[in] nrs the NRS head
919 * \param[in] svcpt the PTLRPC service partition to setup
924 * \pre mutex_is_locked(&nrs_core.nrs_mutex)
926 static int nrs_svcpt_setup_locked0(struct ptlrpc_nrs *nrs,
927 struct ptlrpc_service_part *svcpt)
930 enum ptlrpc_nrs_queue_type queue;
932 LASSERT(mutex_is_locked(&nrs_core.nrs_mutex));
934 if (nrs == &svcpt->scp_nrs_reg)
935 queue = PTLRPC_NRS_QUEUE_REG;
936 else if (nrs == svcpt->scp_nrs_hp)
937 queue = PTLRPC_NRS_QUEUE_HP;
941 nrs->nrs_svcpt = svcpt;
942 nrs->nrs_queue_type = queue;
943 spin_lock_init(&nrs->nrs_lock);
944 INIT_LIST_HEAD(&nrs->nrs_policy_list);
945 INIT_LIST_HEAD(&nrs->nrs_policy_queued);
946 nrs->nrs_throttling = 0;
948 rc = nrs_register_policies_locked(nrs);
954 * Allocates a regular and optionally a high-priority NRS head (if the service
955 * handles high-priority RPCs), and then registers all available compatible
956 * policies on those NRS heads.
958 * \param[in,out] svcpt the PTLRPC service partition to setup
960 * \pre mutex_is_locked(&nrs_core.nrs_mutex)
962 static int nrs_svcpt_setup_locked(struct ptlrpc_service_part *svcpt)
964 struct ptlrpc_nrs *nrs;
968 LASSERT(mutex_is_locked(&nrs_core.nrs_mutex));
971 * Initialize the regular NRS head.
973 nrs = nrs_svcpt2nrs(svcpt, false);
974 rc = nrs_svcpt_setup_locked0(nrs, svcpt);
979 * Optionally allocate a high-priority NRS head.
981 if (svcpt->scp_service->srv_ops.so_hpreq_handler == NULL)
984 OBD_CPT_ALLOC_PTR(svcpt->scp_nrs_hp,
985 svcpt->scp_service->srv_cptable,
987 if (svcpt->scp_nrs_hp == NULL)
988 GOTO(out, rc = -ENOMEM);
990 nrs = nrs_svcpt2nrs(svcpt, true);
991 rc = nrs_svcpt_setup_locked0(nrs, svcpt);
998 * Unregisters all policies on all available NRS heads in a service partition;
999 * called at PTLRPC service unregistration time.
1001 * \param[in] svcpt the PTLRPC service partition
1003 * \pre mutex_is_locked(&nrs_core.nrs_mutex)
1005 static void nrs_svcpt_cleanup_locked(struct ptlrpc_service_part *svcpt)
1007 struct ptlrpc_nrs *nrs;
1008 struct ptlrpc_nrs_policy *policy;
1009 struct ptlrpc_nrs_policy *tmp;
1014 LASSERT(mutex_is_locked(&nrs_core.nrs_mutex));
1017 /* scp_nrs_hp could be NULL due to short of memory. */
1018 nrs = hp ? svcpt->scp_nrs_hp : &svcpt->scp_nrs_reg;
1019 /* check the nrs_svcpt to see if nrs is initialized. */
1020 if (!nrs || !nrs->nrs_svcpt) {
1024 nrs->nrs_stopping = 1;
1026 list_for_each_entry_safe(policy, tmp, &nrs->nrs_policy_list,
1028 rc = nrs_policy_unregister(nrs, policy->pol_desc->pd_name);
1033 * If the service partition has an HP NRS head, clean that up as well.
1035 if (!hp && nrs_svcpt_has_hp(svcpt)) {
1047 * Returns the descriptor for a policy as identified by by \a name.
1049 * \param[in] name the policy name
1051 * \retval the policy descriptor
1054 static struct ptlrpc_nrs_pol_desc *nrs_policy_find_desc_locked(const char *name)
1056 struct ptlrpc_nrs_pol_desc *tmp;
1059 list_for_each_entry(tmp, &nrs_core.nrs_policies, pd_list) {
1060 if (strncmp(tmp->pd_name, name, NRS_POL_NAME_MAX) == 0)
1067 * Removes the policy from all supported NRS heads of all partitions of all
1070 * \param[in] desc the policy descriptor to unregister
1073 * \retval 0 successfully unregistered policy on all supported NRS heads
1075 * \pre mutex_is_locked(&nrs_core.nrs_mutex)
1076 * \pre mutex_is_locked(&ptlrpc_all_services_mutex)
1078 static int nrs_policy_unregister_locked(struct ptlrpc_nrs_pol_desc *desc)
1080 struct ptlrpc_nrs *nrs;
1081 struct ptlrpc_service *svc;
1082 struct ptlrpc_service_part *svcpt;
1087 LASSERT(mutex_is_locked(&nrs_core.nrs_mutex));
1088 LASSERT(mutex_is_locked(&ptlrpc_all_services_mutex));
1090 list_for_each_entry(svc, &ptlrpc_all_services, srv_list) {
1092 if (!nrs_policy_compatible(svc, desc) ||
1093 unlikely(svc->srv_is_stopping))
1096 ptlrpc_service_for_each_part(svcpt, i, svc) {
1100 nrs = nrs_svcpt2nrs(svcpt, hp);
1101 rc = nrs_policy_unregister(nrs, desc->pd_name);
1103 * Ignore -ENOENT as the policy may not have registered
1104 * successfully on all service partitions.
1106 if (rc == -ENOENT) {
1108 } else if (rc != 0) {
1109 CERROR("Failed to unregister NRS policy %s for "
1110 "partition %d of service %s: %d\n",
1111 desc->pd_name, svcpt->scp_cpt,
1112 svcpt->scp_service->srv_name, rc);
1116 if (!hp && nrs_svc_has_hp(svc)) {
1122 if (desc->pd_ops->op_lprocfs_fini != NULL)
1123 desc->pd_ops->op_lprocfs_fini(svc);
1130 * Registers a new policy with NRS core.
1132 * The function will only succeed if policy registration with all compatible
1133 * service partitions (if any) is successful.
1135 * N.B. This function should be called either at ptlrpc module initialization
1136 * time when registering a policy that ships with NRS core, or in a
1137 * module's init() function for policies registering from other modules.
1139 * \param[in] conf configuration information for the new policy to register
1144 int ptlrpc_nrs_policy_register(struct ptlrpc_nrs_pol_conf *conf)
1146 struct ptlrpc_service *svc;
1147 struct ptlrpc_nrs_pol_desc *desc;
1151 LASSERT(conf != NULL);
1152 LASSERT(conf->nc_ops != NULL);
1153 LASSERT(conf->nc_compat != NULL);
1154 LASSERT(ergo(conf->nc_compat == nrs_policy_compat_one,
1155 conf->nc_compat_svc_name != NULL));
1156 LASSERT(ergo((conf->nc_flags & PTLRPC_NRS_FL_REG_EXTERN) != 0,
1157 conf->nc_owner != NULL));
1159 conf->nc_name[NRS_POL_NAME_MAX - 1] = '\0';
1162 * External policies are not allowed to start immediately upon
1163 * registration, as there is a relatively higher chance that their
1164 * registration might fail. In such a case, some policy instances may
1165 * already have requests queued wen unregistration needs to happen as
1166 * part o cleanup; since there is currently no way to drain requests
1167 * from a policy unless the service is unregistering, we just disallow
1170 if ((conf->nc_flags & PTLRPC_NRS_FL_REG_EXTERN) &&
1171 (conf->nc_flags & (PTLRPC_NRS_FL_FALLBACK |
1172 PTLRPC_NRS_FL_REG_START))) {
1173 CERROR("NRS: failing to register policy %s. Please check "
1174 "policy flags; external policies cannot act as fallback "
1175 "policies, or be started immediately upon registration "
1176 "without interaction with lprocfs\n", conf->nc_name);
1180 mutex_lock(&nrs_core.nrs_mutex);
1182 if (nrs_policy_find_desc_locked(conf->nc_name) != NULL) {
1183 CERROR("NRS: failing to register policy %s which has already "
1184 "been registered with NRS core!\n",
1186 GOTO(fail, rc = -EEXIST);
1189 OBD_ALLOC_PTR(desc);
1191 GOTO(fail, rc = -ENOMEM);
1193 if (strlcpy(desc->pd_name, conf->nc_name, sizeof(desc->pd_name)) >=
1194 sizeof(desc->pd_name)) {
1196 GOTO(fail, rc = -E2BIG);
1198 desc->pd_ops = conf->nc_ops;
1199 desc->pd_compat = conf->nc_compat;
1200 desc->pd_compat_svc_name = conf->nc_compat_svc_name;
1201 if ((conf->nc_flags & PTLRPC_NRS_FL_REG_EXTERN) != 0)
1202 desc->pd_owner = conf->nc_owner;
1203 desc->pd_flags = conf->nc_flags;
1204 atomic_set(&desc->pd_refs, 0);
1207 * For policies that are held in the same module as NRS (currently
1208 * ptlrpc), do not register the policy with all compatible services,
1209 * as the services will not have started at this point, since we are
1210 * calling from ptlrpc module initialization code. In such cases each
1211 * service will register all compatible policies later, via
1212 * ptlrpc_service_nrs_setup().
1214 if ((conf->nc_flags & PTLRPC_NRS_FL_REG_EXTERN) == 0)
1218 * Register the new policy on all compatible services
1220 mutex_lock(&ptlrpc_all_services_mutex);
1222 list_for_each_entry(svc, &ptlrpc_all_services, srv_list) {
1223 struct ptlrpc_service_part *svcpt;
1227 if (!nrs_policy_compatible(svc, desc) ||
1228 unlikely(svc->srv_is_stopping))
1231 ptlrpc_service_for_each_part(svcpt, i, svc) {
1232 struct ptlrpc_nrs *nrs;
1235 nrs = nrs_svcpt2nrs(svcpt, hp);
1236 rc = nrs_policy_register(nrs, desc);
1238 CERROR("Failed to register NRS policy %s for "
1239 "partition %d of service %s: %d\n",
1240 desc->pd_name, svcpt->scp_cpt,
1241 svcpt->scp_service->srv_name, rc);
1243 rc2 = nrs_policy_unregister_locked(desc);
1245 * Should not fail at this point
1248 mutex_unlock(&ptlrpc_all_services_mutex);
1253 if (!hp && nrs_svc_has_hp(svc)) {
1260 * No need to take a reference to other modules here, as we
1261 * will be calling from the module's init() function.
1263 if (desc->pd_ops->op_lprocfs_init != NULL) {
1264 rc = desc->pd_ops->op_lprocfs_init(svc);
1266 rc2 = nrs_policy_unregister_locked(desc);
1268 * Should not fail at this point
1271 mutex_unlock(&ptlrpc_all_services_mutex);
1278 mutex_unlock(&ptlrpc_all_services_mutex);
1280 list_add_tail(&desc->pd_list, &nrs_core.nrs_policies);
1282 mutex_unlock(&nrs_core.nrs_mutex);
1286 EXPORT_SYMBOL(ptlrpc_nrs_policy_register);
1289 * Unregisters a previously registered policy with NRS core. All instances of
1290 * the policy on all NRS heads of all supported services are removed.
1292 * N.B. This function should only be called from a module's exit() function.
1293 * Although it can be used for policies that ship alongside NRS core, the
1294 * function is primarily intended for policies that register externally,
1295 * from other modules.
1297 * \param[in] conf configuration information for the policy to unregister
1302 int ptlrpc_nrs_policy_unregister(struct ptlrpc_nrs_pol_conf *conf)
1304 struct ptlrpc_nrs_pol_desc *desc;
1308 LASSERT(conf != NULL);
1310 if (conf->nc_flags & PTLRPC_NRS_FL_FALLBACK) {
1311 CERROR("Unable to unregister a fallback policy, unless the "
1312 "PTLRPC service is stopping.\n");
1316 conf->nc_name[NRS_POL_NAME_MAX - 1] = '\0';
1318 mutex_lock(&nrs_core.nrs_mutex);
1320 desc = nrs_policy_find_desc_locked(conf->nc_name);
1322 CERROR("Failing to unregister NRS policy %s which has "
1323 "not been registered with NRS core!\n",
1325 GOTO(not_exist, rc = -ENOENT);
1328 mutex_lock(&ptlrpc_all_services_mutex);
1330 rc = nrs_policy_unregister_locked(desc);
1333 CERROR("Please first stop policy %s on all service "
1334 "partitions and then retry to unregister the "
1335 "policy.\n", conf->nc_name);
1339 CDEBUG(D_INFO, "Unregistering policy %s from NRS core.\n",
1342 list_del(&desc->pd_list);
1346 mutex_unlock(&ptlrpc_all_services_mutex);
1349 mutex_unlock(&nrs_core.nrs_mutex);
1353 EXPORT_SYMBOL(ptlrpc_nrs_policy_unregister);
1356 * Setup NRS heads on all service partitions of service \a svc, and register
1357 * all compatible policies on those NRS heads.
1359 * To be called from withing ptl
1360 * \param[in] svc the service to setup
1362 * \retval -ve error, the calling logic should eventually call
1363 * ptlrpc_service_nrs_cleanup() to undo any work performed
1366 * \see ptlrpc_register_service()
1367 * \see ptlrpc_service_nrs_cleanup()
1369 int ptlrpc_service_nrs_setup(struct ptlrpc_service *svc)
1371 struct ptlrpc_service_part *svcpt;
1372 const struct ptlrpc_nrs_pol_desc *desc;
1376 mutex_lock(&nrs_core.nrs_mutex);
1379 * Initialize NRS heads on all service CPTs.
1381 ptlrpc_service_for_each_part(svcpt, i, svc) {
1382 rc = nrs_svcpt_setup_locked(svcpt);
1388 * Set up lprocfs interfaces for all supported policies for the
1391 list_for_each_entry(desc, &nrs_core.nrs_policies, pd_list) {
1392 if (!nrs_policy_compatible(svc, desc))
1395 if (desc->pd_ops->op_lprocfs_init != NULL) {
1396 rc = desc->pd_ops->op_lprocfs_init(svc);
1404 mutex_unlock(&nrs_core.nrs_mutex);
1410 * Unregisters all policies on all service partitions of service \a svc.
1412 * \param[in] svc the PTLRPC service to unregister
1414 void ptlrpc_service_nrs_cleanup(struct ptlrpc_service *svc)
1416 struct ptlrpc_service_part *svcpt;
1417 const struct ptlrpc_nrs_pol_desc *desc;
1420 mutex_lock(&nrs_core.nrs_mutex);
1423 * Clean up NRS heads on all service partitions
1425 ptlrpc_service_for_each_part(svcpt, i, svc)
1426 nrs_svcpt_cleanup_locked(svcpt);
1429 * Clean up lprocfs interfaces for all supported policies for the
1432 list_for_each_entry(desc, &nrs_core.nrs_policies, pd_list) {
1433 if (!nrs_policy_compatible(svc, desc))
1436 if (desc->pd_ops->op_lprocfs_fini != NULL)
1437 desc->pd_ops->op_lprocfs_fini(svc);
1440 mutex_unlock(&nrs_core.nrs_mutex);
1444 * Obtains NRS head resources for request \a req.
1446 * These could be either on the regular or HP NRS head of \a svcpt; resources
1447 * taken on the regular head can later be swapped for HP head resources by
1448 * ldlm_lock_reorder_req().
1450 * \param[in] svcpt the service partition
1451 * \param[in] req the request
1452 * \param[in] hp which NRS head of \a svcpt to use
1454 void ptlrpc_nrs_req_initialize(struct ptlrpc_service_part *svcpt,
1455 struct ptlrpc_request *req, bool hp)
1457 struct ptlrpc_nrs *nrs = nrs_svcpt2nrs(svcpt, hp);
1459 memset(&req->rq_nrq, 0, sizeof(req->rq_nrq));
1460 nrs_resource_get_safe(nrs, &req->rq_nrq, req->rq_nrq.nr_res_ptrs,
1464 * It is fine to access \e nr_initialized without locking as there is
1465 * no contention at this early stage.
1467 req->rq_nrq.nr_initialized = 1;
1471 * Releases resources for a request; is called after the request has been
1474 * \param[in] req the request
1476 * \see ptlrpc_server_finish_request()
1478 void ptlrpc_nrs_req_finalize(struct ptlrpc_request *req)
1480 if (req->rq_nrq.nr_initialized) {
1481 nrs_resource_put_safe(req->rq_nrq.nr_res_ptrs);
1482 /* no protection on bit nr_initialized because no
1483 * contention at this late stage */
1484 req->rq_nrq.nr_finalized = 1;
1488 void ptlrpc_nrs_req_stop_nolock(struct ptlrpc_request *req)
1490 if (req->rq_nrq.nr_started)
1491 nrs_request_stop(&req->rq_nrq);
1495 * Enqueues request \a req on either the regular or high-priority NRS head
1496 * of service partition \a svcpt.
1498 * \param[in] svcpt the service partition
1499 * \param[in] req the request to be enqueued
1500 * \param[in] hp whether to enqueue the request on the regular or
1501 * high-priority NRS head.
1503 void ptlrpc_nrs_req_add(struct ptlrpc_service_part *svcpt,
1504 struct ptlrpc_request *req, bool hp)
1506 spin_lock(&svcpt->scp_req_lock);
1509 ptlrpc_nrs_hpreq_add_nolock(req);
1511 ptlrpc_nrs_req_add_nolock(req);
1513 spin_unlock(&svcpt->scp_req_lock);
1516 static void nrs_request_removed(struct ptlrpc_nrs_policy *policy)
1518 LASSERT(policy->pol_nrs->nrs_req_queued > 0);
1519 LASSERT(policy->pol_req_queued > 0);
1521 policy->pol_nrs->nrs_req_queued--;
1522 policy->pol_req_queued--;
1525 * If the policy has no more requests queued, remove it from
1526 * ptlrpc_nrs::nrs_policy_queued.
1528 if (unlikely(policy->pol_req_queued == 0)) {
1529 list_del_init(&policy->pol_list_queued);
1532 * If there are other policies with queued requests, move the
1533 * current policy to the end so that we can round robin over
1534 * all policies and drain the requests.
1536 } else if (policy->pol_req_queued != policy->pol_nrs->nrs_req_queued) {
1537 LASSERT(policy->pol_req_queued <
1538 policy->pol_nrs->nrs_req_queued);
1540 list_move_tail(&policy->pol_list_queued,
1541 &policy->pol_nrs->nrs_policy_queued);
1546 * Obtains a request for handling from an NRS head of service partition
1549 * \param[in] svcpt the service partition
1550 * \param[in] hp whether to obtain a request from the regular or
1551 * high-priority NRS head.
1552 * \param[in] peek when set, signifies that we just want to examine the
1553 * request, and not handle it, so the request is not removed
1555 * \param[in] force when set, it will force a policy to return a request if it
1558 * \retval the request to be handled
1559 * \retval NULL the head has no requests to serve
1561 struct ptlrpc_request *
1562 ptlrpc_nrs_req_get_nolock0(struct ptlrpc_service_part *svcpt, bool hp,
1563 bool peek, bool force)
1565 struct ptlrpc_nrs *nrs = nrs_svcpt2nrs(svcpt, hp);
1566 struct ptlrpc_nrs_policy *policy;
1567 struct ptlrpc_nrs_request *nrq;
1570 * Always try to drain requests from all NRS polices even if they are
1571 * inactive, because the user can change policy status at runtime.
1573 list_for_each_entry(policy, &nrs->nrs_policy_queued,
1575 nrq = nrs_request_get(policy, peek, force);
1577 if (likely(!peek)) {
1578 nrq->nr_started = 1;
1580 policy->pol_req_started++;
1581 policy->pol_nrs->nrs_req_started++;
1583 nrs_request_removed(policy);
1586 return container_of(nrq, struct ptlrpc_request, rq_nrq);
1594 * Dequeues request \a req from the policy it has been enqueued on.
1596 * \param[in] req the request
1598 void ptlrpc_nrs_req_del_nolock(struct ptlrpc_request *req)
1600 struct ptlrpc_nrs_policy *policy = nrs_request_policy(&req->rq_nrq);
1602 policy->pol_desc->pd_ops->op_req_dequeue(policy, &req->rq_nrq);
1604 req->rq_nrq.nr_enqueued = 0;
1606 nrs_request_removed(policy);
1610 * Returns whether there are any requests currently enqueued on any of the
1611 * policies of service partition's \a svcpt NRS head specified by \a hp. Should
1612 * be called while holding ptlrpc_service_part::scp_req_lock to get a reliable
1615 * \param[in] svcpt the service partition to enquire.
1616 * \param[in] hp whether the regular or high-priority NRS head is to be
1619 * \retval false the indicated NRS head has no enqueued requests.
1620 * \retval true the indicated NRS head has some enqueued requests.
1622 bool ptlrpc_nrs_req_pending_nolock(struct ptlrpc_service_part *svcpt, bool hp)
1624 struct ptlrpc_nrs *nrs = nrs_svcpt2nrs(svcpt, hp);
1626 return nrs->nrs_req_queued > 0;
1630 * Returns whether NRS policy is throttling reqeust
1632 * \param[in] svcpt the service partition to enquire.
1633 * \param[in] hp whether the regular or high-priority NRS head is to be
1636 * \retval false the indicated NRS head has no enqueued requests.
1637 * \retval true the indicated NRS head has some enqueued requests.
1639 bool ptlrpc_nrs_req_throttling_nolock(struct ptlrpc_service_part *svcpt,
1642 struct ptlrpc_nrs *nrs = nrs_svcpt2nrs(svcpt, hp);
1644 return !!nrs->nrs_throttling;
1648 * Moves request \a req from the regular to the high-priority NRS head.
1650 * \param[in] req the request to move
1652 void ptlrpc_nrs_req_hp_move(struct ptlrpc_request *req)
1654 struct ptlrpc_service_part *svcpt = req->rq_rqbd->rqbd_svcpt;
1655 struct ptlrpc_nrs_request *nrq = &req->rq_nrq;
1656 struct ptlrpc_nrs_resource *res1[NRS_RES_MAX];
1657 struct ptlrpc_nrs_resource *res2[NRS_RES_MAX];
1661 * Obtain the high-priority NRS head resources.
1663 nrs_resource_get_safe(nrs_svcpt2nrs(svcpt, true), nrq, res1, true);
1665 spin_lock(&svcpt->scp_req_lock);
1667 if (!ptlrpc_nrs_req_can_move(req))
1670 ptlrpc_nrs_req_del_nolock(req);
1672 memcpy(res2, nrq->nr_res_ptrs, NRS_RES_MAX * sizeof(res2[0]));
1673 memcpy(nrq->nr_res_ptrs, res1, NRS_RES_MAX * sizeof(res1[0]));
1675 ptlrpc_nrs_hpreq_add_nolock(req);
1677 memcpy(res1, res2, NRS_RES_MAX * sizeof(res1[0]));
1679 spin_unlock(&svcpt->scp_req_lock);
1682 * Release either the regular NRS head resources if we moved the
1683 * request, or the high-priority NRS head resources if we took a
1684 * reference earlier in this function and ptlrpc_nrs_req_can_move()
1687 nrs_resource_put_safe(res1);
1692 * Carries out a control operation \a opc on the policy identified by the
1693 * human-readable \a name, on either all partitions, or only on the first
1694 * partition of service \a svc.
1696 * \param[in] svc the service the policy belongs to.
1697 * \param[in] queue whether to carry out the command on the policy which
1698 * belongs to the regular, high-priority, or both NRS
1699 * heads of service partitions of \a svc.
1700 * \param[in] name the policy to act upon, by human-readable name
1701 * \param[in] opc the opcode of the operation to carry out
1702 * \param[in] single when set, the operation will only be carried out on the
1703 * NRS heads of the first service partition of \a svc.
1704 * This is useful for some policies which e.g. share
1705 * identical values on the same parameters of different
1706 * service partitions; when reading these parameters via
1707 * lprocfs, these policies may just want to obtain and
1708 * print out the values from the first service partition.
1709 * Storing these values centrally elsewhere then could be
1710 * another solution for this.
1711 * \param[in,out] arg can be used as a generic in/out buffer between control
1712 * operations and the user environment.
1714 *\retval -ve error condition
1715 *\retval 0 operation was carried out successfully
1717 int ptlrpc_nrs_policy_control(const struct ptlrpc_service *svc,
1718 enum ptlrpc_nrs_queue_type queue, char *name,
1719 enum ptlrpc_nrs_ctl opc, bool single, void *arg)
1721 struct ptlrpc_service_part *svcpt;
1726 LASSERT(opc != PTLRPC_NRS_CTL_INVALID);
1728 if ((queue & PTLRPC_NRS_QUEUE_BOTH) == 0)
1731 ptlrpc_service_for_each_part(svcpt, i, svc) {
1732 if ((queue & PTLRPC_NRS_QUEUE_REG) != 0) {
1733 rc = nrs_policy_ctl(nrs_svcpt2nrs(svcpt, false), name,
1735 if (rc != 0 || (queue == PTLRPC_NRS_QUEUE_REG &&
1740 if ((queue & PTLRPC_NRS_QUEUE_HP) != 0) {
1742 * XXX: We could optionally check for
1743 * nrs_svc_has_hp(svc) here, and return an error if it
1744 * is false. Right now we rely on the policies' lprocfs
1745 * handlers that call the present function to make this
1746 * check; if they fail to do so, they might hit the
1747 * assertion inside nrs_svcpt2nrs() below.
1749 rc = nrs_policy_ctl(nrs_svcpt2nrs(svcpt, true), name,
1751 if (rc != 0 || single)
1760 /* ptlrpc/nrs_fifo.c */
1761 extern struct ptlrpc_nrs_pol_conf nrs_conf_fifo;
1762 #ifdef HAVE_SERVER_SUPPORT
1763 /* ptlrpc/nrs_crr.c */
1764 extern struct ptlrpc_nrs_pol_conf nrs_conf_crrn;
1765 /* ptlrpc/nrs_orr.c */
1766 extern struct ptlrpc_nrs_pol_conf nrs_conf_orr;
1767 extern struct ptlrpc_nrs_pol_conf nrs_conf_trr;
1768 extern struct ptlrpc_nrs_pol_conf nrs_conf_tbf;
1769 #endif /* HAVE_SERVER_SUPPORT */
1772 * Adds all policies that ship with the ptlrpc module, to NRS core's list of
1773 * policies \e nrs_core.nrs_policies.
1775 * \retval 0 all policies have been registered successfully
1778 int ptlrpc_nrs_init(void)
1783 mutex_init(&nrs_core.nrs_mutex);
1784 INIT_LIST_HEAD(&nrs_core.nrs_policies);
1786 rc = ptlrpc_nrs_policy_register(&nrs_conf_fifo);
1790 #ifdef HAVE_SERVER_SUPPORT
1791 rc = ptlrpc_nrs_policy_register(&nrs_conf_crrn);
1795 rc = ptlrpc_nrs_policy_register(&nrs_conf_orr);
1799 rc = ptlrpc_nrs_policy_register(&nrs_conf_trr);
1802 rc = ptlrpc_nrs_policy_register(&nrs_conf_tbf);
1805 #endif /* HAVE_SERVER_SUPPORT */
1810 * Since no PTLRPC services have been started at this point, all we need
1811 * to do for cleanup is to free the descriptors.
1819 * Removes all policy desciptors from nrs_core::nrs_policies, and frees the
1820 * policy descriptors.
1822 * Since all PTLRPC services are stopped at this point, there are no more
1823 * instances of any policies, because each service will have stopped its policy
1824 * instances in ptlrpc_service_nrs_cleanup(), so we just need to free the
1827 void ptlrpc_nrs_fini(void)
1829 struct ptlrpc_nrs_pol_desc *desc;
1830 struct ptlrpc_nrs_pol_desc *tmp;
1832 list_for_each_entry_safe(desc, tmp, &nrs_core.nrs_policies,
1834 list_del_init(&desc->pd_list);