| /* |
| * 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) 2003, 2010, Oracle and/or its affiliates. All rights reserved. |
| * Use is subject to license terms. |
| * |
| * Copyright (c) 2011, 2012, Intel Corporation. |
| */ |
| /* |
| * This file is part of Lustre, http://www.lustre.org/ |
| * Lustre is a trademark of Sun Microsystems, Inc. |
| * |
| * lustre/ptlrpc/ptlrpcd.c |
| */ |
| |
| /** \defgroup ptlrpcd PortalRPC daemon |
| * |
| * ptlrpcd is a special thread with its own set where other user might add |
| * requests when they don't want to wait for their completion. |
| * PtlRPCD will take care of sending such requests and then processing their |
| * replies and calling completion callbacks as necessary. |
| * The callbacks are called directly from ptlrpcd context. |
| * It is important to never significantly block (esp. on RPCs!) within such |
| * completion handler or a deadlock might occur where ptlrpcd enters some |
| * callback that attempts to send another RPC and wait for it to return, |
| * during which time ptlrpcd is completely blocked, so e.g. if import |
| * fails, recovery cannot progress because connection requests are also |
| * sent by ptlrpcd. |
| * |
| * @{ |
| */ |
| |
| #define DEBUG_SUBSYSTEM S_RPC |
| |
| #include "../../include/linux/libcfs/libcfs.h" |
| |
| #include "../include/lustre_net.h" |
| #include "../include/lustre_lib.h" |
| #include "../include/lustre_ha.h" |
| #include "../include/obd_class.h" /* for obd_zombie */ |
| #include "../include/obd_support.h" /* for OBD_FAIL_CHECK */ |
| #include "../include/cl_object.h" /* cl_env_{get,put}() */ |
| #include "../include/lprocfs_status.h" |
| |
| #include "ptlrpc_internal.h" |
| |
| struct ptlrpcd { |
| int pd_size; |
| int pd_index; |
| int pd_nthreads; |
| struct ptlrpcd_ctl pd_thread_rcv; |
| struct ptlrpcd_ctl pd_threads[0]; |
| }; |
| |
| static int max_ptlrpcds; |
| module_param(max_ptlrpcds, int, 0644); |
| MODULE_PARM_DESC(max_ptlrpcds, "Max ptlrpcd thread count to be started."); |
| |
| static int ptlrpcd_bind_policy = PDB_POLICY_PAIR; |
| module_param(ptlrpcd_bind_policy, int, 0644); |
| MODULE_PARM_DESC(ptlrpcd_bind_policy, "Ptlrpcd threads binding mode."); |
| static struct ptlrpcd *ptlrpcds; |
| |
| struct mutex ptlrpcd_mutex; |
| static int ptlrpcd_users; |
| |
| void ptlrpcd_wake(struct ptlrpc_request *req) |
| { |
| struct ptlrpc_request_set *rq_set = req->rq_set; |
| |
| LASSERT(rq_set != NULL); |
| |
| wake_up(&rq_set->set_waitq); |
| } |
| EXPORT_SYMBOL(ptlrpcd_wake); |
| |
| static struct ptlrpcd_ctl * |
| ptlrpcd_select_pc(struct ptlrpc_request *req, pdl_policy_t policy, int index) |
| { |
| int idx = 0; |
| |
| if (req != NULL && req->rq_send_state != LUSTRE_IMP_FULL) |
| return &ptlrpcds->pd_thread_rcv; |
| |
| switch (policy) { |
| case PDL_POLICY_SAME: |
| idx = smp_processor_id() % ptlrpcds->pd_nthreads; |
| break; |
| case PDL_POLICY_LOCAL: |
| /* Before CPU partition patches available, process it the same |
| * as "PDL_POLICY_ROUND". */ |
| # ifdef CFS_CPU_MODE_NUMA |
| # warning "fix this code to use new CPU partition APIs" |
| # endif |
| /* Fall through to PDL_POLICY_ROUND until the CPU |
| * CPU partition patches are available. */ |
| index = -1; |
| case PDL_POLICY_PREFERRED: |
| if (index >= 0 && index < num_online_cpus()) { |
| idx = index % ptlrpcds->pd_nthreads; |
| break; |
| } |
| /* Fall through to PDL_POLICY_ROUND for bad index. */ |
| default: |
| /* Fall through to PDL_POLICY_ROUND for unknown policy. */ |
| case PDL_POLICY_ROUND: |
| /* We do not care whether it is strict load balance. */ |
| idx = ptlrpcds->pd_index + 1; |
| if (idx == smp_processor_id()) |
| idx++; |
| idx %= ptlrpcds->pd_nthreads; |
| ptlrpcds->pd_index = idx; |
| break; |
| } |
| |
| return &ptlrpcds->pd_threads[idx]; |
| } |
| |
| /** |
| * Move all request from an existing request set to the ptlrpcd queue. |
| * All requests from the set must be in phase RQ_PHASE_NEW. |
| */ |
| void ptlrpcd_add_rqset(struct ptlrpc_request_set *set) |
| { |
| struct list_head *tmp, *pos; |
| struct ptlrpcd_ctl *pc; |
| struct ptlrpc_request_set *new; |
| int count, i; |
| |
| pc = ptlrpcd_select_pc(NULL, PDL_POLICY_LOCAL, -1); |
| new = pc->pc_set; |
| |
| list_for_each_safe(pos, tmp, &set->set_requests) { |
| struct ptlrpc_request *req = |
| list_entry(pos, struct ptlrpc_request, |
| rq_set_chain); |
| |
| LASSERT(req->rq_phase == RQ_PHASE_NEW); |
| req->rq_set = new; |
| req->rq_queued_time = cfs_time_current(); |
| } |
| |
| spin_lock(&new->set_new_req_lock); |
| list_splice_init(&set->set_requests, &new->set_new_requests); |
| i = atomic_read(&set->set_remaining); |
| count = atomic_add_return(i, &new->set_new_count); |
| atomic_set(&set->set_remaining, 0); |
| spin_unlock(&new->set_new_req_lock); |
| if (count == i) { |
| wake_up(&new->set_waitq); |
| |
| /* XXX: It maybe unnecessary to wakeup all the partners. But to |
| * guarantee the async RPC can be processed ASAP, we have |
| * no other better choice. It maybe fixed in future. */ |
| for (i = 0; i < pc->pc_npartners; i++) |
| wake_up(&pc->pc_partners[i]->pc_set->set_waitq); |
| } |
| } |
| EXPORT_SYMBOL(ptlrpcd_add_rqset); |
| |
| /** |
| * Return transferred RPCs count. |
| */ |
| static int ptlrpcd_steal_rqset(struct ptlrpc_request_set *des, |
| struct ptlrpc_request_set *src) |
| { |
| struct list_head *tmp, *pos; |
| struct ptlrpc_request *req; |
| int rc = 0; |
| |
| spin_lock(&src->set_new_req_lock); |
| if (likely(!list_empty(&src->set_new_requests))) { |
| list_for_each_safe(pos, tmp, &src->set_new_requests) { |
| req = list_entry(pos, struct ptlrpc_request, |
| rq_set_chain); |
| req->rq_set = des; |
| } |
| list_splice_init(&src->set_new_requests, |
| &des->set_requests); |
| rc = atomic_read(&src->set_new_count); |
| atomic_add(rc, &des->set_remaining); |
| atomic_set(&src->set_new_count, 0); |
| } |
| spin_unlock(&src->set_new_req_lock); |
| return rc; |
| } |
| |
| /** |
| * Requests that are added to the ptlrpcd queue are sent via |
| * ptlrpcd_check->ptlrpc_check_set(). |
| */ |
| void ptlrpcd_add_req(struct ptlrpc_request *req, pdl_policy_t policy, int idx) |
| { |
| struct ptlrpcd_ctl *pc; |
| |
| if (req->rq_reqmsg) |
| lustre_msg_set_jobid(req->rq_reqmsg, NULL); |
| |
| spin_lock(&req->rq_lock); |
| if (req->rq_invalid_rqset) { |
| struct l_wait_info lwi = LWI_TIMEOUT(cfs_time_seconds(5), |
| back_to_sleep, NULL); |
| |
| req->rq_invalid_rqset = 0; |
| spin_unlock(&req->rq_lock); |
| l_wait_event(req->rq_set_waitq, (req->rq_set == NULL), &lwi); |
| } else if (req->rq_set) { |
| /* If we have a valid "rq_set", just reuse it to avoid double |
| * linked. */ |
| LASSERT(req->rq_phase == RQ_PHASE_NEW); |
| LASSERT(req->rq_send_state == LUSTRE_IMP_REPLAY); |
| |
| /* ptlrpc_check_set will decrease the count */ |
| atomic_inc(&req->rq_set->set_remaining); |
| spin_unlock(&req->rq_lock); |
| wake_up(&req->rq_set->set_waitq); |
| return; |
| } else { |
| spin_unlock(&req->rq_lock); |
| } |
| |
| pc = ptlrpcd_select_pc(req, policy, idx); |
| |
| DEBUG_REQ(D_INFO, req, "add req [%p] to pc [%s:%d]", |
| req, pc->pc_name, pc->pc_index); |
| |
| ptlrpc_set_add_new_req(pc, req); |
| } |
| EXPORT_SYMBOL(ptlrpcd_add_req); |
| |
| static inline void ptlrpc_reqset_get(struct ptlrpc_request_set *set) |
| { |
| atomic_inc(&set->set_refcount); |
| } |
| |
| /** |
| * Check if there is more work to do on ptlrpcd set. |
| * Returns 1 if yes. |
| */ |
| static int ptlrpcd_check(struct lu_env *env, struct ptlrpcd_ctl *pc) |
| { |
| struct list_head *tmp, *pos; |
| struct ptlrpc_request *req; |
| struct ptlrpc_request_set *set = pc->pc_set; |
| int rc = 0; |
| int rc2; |
| |
| if (atomic_read(&set->set_new_count)) { |
| spin_lock(&set->set_new_req_lock); |
| if (likely(!list_empty(&set->set_new_requests))) { |
| list_splice_init(&set->set_new_requests, |
| &set->set_requests); |
| atomic_add(atomic_read(&set->set_new_count), |
| &set->set_remaining); |
| atomic_set(&set->set_new_count, 0); |
| /* |
| * Need to calculate its timeout. |
| */ |
| rc = 1; |
| } |
| spin_unlock(&set->set_new_req_lock); |
| } |
| |
| /* We should call lu_env_refill() before handling new requests to make |
| * sure that env key the requests depending on really exists. |
| */ |
| rc2 = lu_env_refill(env); |
| if (rc2 != 0) { |
| /* |
| * XXX This is very awkward situation, because |
| * execution can neither continue (request |
| * interpreters assume that env is set up), nor repeat |
| * the loop (as this potentially results in a tight |
| * loop of -ENOMEM's). |
| * |
| * Fortunately, refill only ever does something when |
| * new modules are loaded, i.e., early during boot up. |
| */ |
| CERROR("Failure to refill session: %d\n", rc2); |
| return rc; |
| } |
| |
| if (atomic_read(&set->set_remaining)) |
| rc |= ptlrpc_check_set(env, set); |
| |
| /* NB: ptlrpc_check_set has already moved completed request at the |
| * head of seq::set_requests */ |
| list_for_each_safe(pos, tmp, &set->set_requests) { |
| req = list_entry(pos, struct ptlrpc_request, rq_set_chain); |
| if (req->rq_phase != RQ_PHASE_COMPLETE) |
| break; |
| |
| list_del_init(&req->rq_set_chain); |
| req->rq_set = NULL; |
| ptlrpc_req_finished(req); |
| } |
| |
| if (rc == 0) { |
| /* |
| * If new requests have been added, make sure to wake up. |
| */ |
| rc = atomic_read(&set->set_new_count); |
| |
| /* If we have nothing to do, check whether we can take some |
| * work from our partner threads. */ |
| if (rc == 0 && pc->pc_npartners > 0) { |
| struct ptlrpcd_ctl *partner; |
| struct ptlrpc_request_set *ps; |
| int first = pc->pc_cursor; |
| |
| do { |
| partner = pc->pc_partners[pc->pc_cursor++]; |
| if (pc->pc_cursor >= pc->pc_npartners) |
| pc->pc_cursor = 0; |
| if (partner == NULL) |
| continue; |
| |
| spin_lock(&partner->pc_lock); |
| ps = partner->pc_set; |
| if (ps == NULL) { |
| spin_unlock(&partner->pc_lock); |
| continue; |
| } |
| |
| ptlrpc_reqset_get(ps); |
| spin_unlock(&partner->pc_lock); |
| |
| if (atomic_read(&ps->set_new_count)) { |
| rc = ptlrpcd_steal_rqset(set, ps); |
| if (rc > 0) |
| CDEBUG(D_RPCTRACE, "transfer %d async RPCs [%d->%d]\n", |
| rc, partner->pc_index, |
| pc->pc_index); |
| } |
| ptlrpc_reqset_put(ps); |
| } while (rc == 0 && pc->pc_cursor != first); |
| } |
| } |
| |
| return rc; |
| } |
| |
| /** |
| * Main ptlrpcd thread. |
| * ptlrpc's code paths like to execute in process context, so we have this |
| * thread which spins on a set which contains the rpcs and sends them. |
| * |
| */ |
| static int ptlrpcd(void *arg) |
| { |
| struct ptlrpcd_ctl *pc = arg; |
| struct ptlrpc_request_set *set = pc->pc_set; |
| struct lu_env env = { .le_ses = NULL }; |
| int rc, exit = 0; |
| |
| unshare_fs_struct(); |
| #if defined(CONFIG_SMP) |
| if (test_bit(LIOD_BIND, &pc->pc_flags)) { |
| int index = pc->pc_index; |
| |
| if (index >= 0 && index < num_possible_cpus()) { |
| while (!cpu_online(index)) { |
| if (++index >= num_possible_cpus()) |
| index = 0; |
| } |
| set_cpus_allowed_ptr(current, |
| cpumask_of_node(cpu_to_node(index))); |
| } |
| } |
| #endif |
| /* |
| * XXX So far only "client" ptlrpcd uses an environment. In |
| * the future, ptlrpcd thread (or a thread-set) has to given |
| * an argument, describing its "scope". |
| */ |
| rc = lu_context_init(&env.le_ctx, |
| LCT_CL_THREAD|LCT_REMEMBER|LCT_NOREF); |
| complete(&pc->pc_starting); |
| |
| if (rc != 0) |
| return rc; |
| |
| /* |
| * This mainloop strongly resembles ptlrpc_set_wait() except that our |
| * set never completes. ptlrpcd_check() calls ptlrpc_check_set() when |
| * there are requests in the set. New requests come in on the set's |
| * new_req_list and ptlrpcd_check() moves them into the set. |
| */ |
| do { |
| struct l_wait_info lwi; |
| int timeout; |
| |
| timeout = ptlrpc_set_next_timeout(set); |
| lwi = LWI_TIMEOUT(cfs_time_seconds(timeout ? timeout : 1), |
| ptlrpc_expired_set, set); |
| |
| lu_context_enter(&env.le_ctx); |
| l_wait_event(set->set_waitq, |
| ptlrpcd_check(&env, pc), &lwi); |
| lu_context_exit(&env.le_ctx); |
| |
| /* |
| * Abort inflight rpcs for forced stop case. |
| */ |
| if (test_bit(LIOD_STOP, &pc->pc_flags)) { |
| if (test_bit(LIOD_FORCE, &pc->pc_flags)) |
| ptlrpc_abort_set(set); |
| exit++; |
| } |
| |
| /* |
| * Let's make one more loop to make sure that ptlrpcd_check() |
| * copied all raced new rpcs into the set so we can kill them. |
| */ |
| } while (exit < 2); |
| |
| /* |
| * Wait for inflight requests to drain. |
| */ |
| if (!list_empty(&set->set_requests)) |
| ptlrpc_set_wait(set); |
| lu_context_fini(&env.le_ctx); |
| |
| complete(&pc->pc_finishing); |
| |
| return 0; |
| } |
| |
| /* XXX: We want multiple CPU cores to share the async RPC load. So we start many |
| * ptlrpcd threads. We also want to reduce the ptlrpcd overhead caused by |
| * data transfer cross-CPU cores. So we bind ptlrpcd thread to specified |
| * CPU core. But binding all ptlrpcd threads maybe cause response delay |
| * because of some CPU core(s) busy with other loads. |
| * |
| * For example: "ls -l", some async RPCs for statahead are assigned to |
| * ptlrpcd_0, and ptlrpcd_0 is bound to CPU_0, but CPU_0 may be quite busy |
| * with other non-ptlrpcd, like "ls -l" itself (we want to the "ls -l" |
| * thread, statahead thread, and ptlrpcd thread can run in parallel), under |
| * such case, the statahead async RPCs can not be processed in time, it is |
| * unexpected. If ptlrpcd_0 can be re-scheduled on other CPU core, it may |
| * be better. But it breaks former data transfer policy. |
| * |
| * So we shouldn't be blind for avoiding the data transfer. We make some |
| * compromise: divide the ptlrpcd threads pool into two parts. One part is |
| * for bound mode, each ptlrpcd thread in this part is bound to some CPU |
| * core. The other part is for free mode, all the ptlrpcd threads in the |
| * part can be scheduled on any CPU core. We specify some partnership |
| * between bound mode ptlrpcd thread(s) and free mode ptlrpcd thread(s), |
| * and the async RPC load within the partners are shared. |
| * |
| * It can partly avoid data transfer cross-CPU (if the bound mode ptlrpcd |
| * thread can be scheduled in time), and try to guarantee the async RPC |
| * processed ASAP (as long as the free mode ptlrpcd thread can be scheduled |
| * on any CPU core). |
| * |
| * As for how to specify the partnership between bound mode ptlrpcd |
| * thread(s) and free mode ptlrpcd thread(s), the simplest way is to use |
| * <free bound> pair. In future, we can specify some more complex |
| * partnership based on the patches for CPU partition. But before such |
| * patches are available, we prefer to use the simplest one. |
| */ |
| # ifdef CFS_CPU_MODE_NUMA |
| # warning "fix ptlrpcd_bind() to use new CPU partition APIs" |
| # endif |
| static int ptlrpcd_bind(int index, int max) |
| { |
| struct ptlrpcd_ctl *pc; |
| int rc = 0; |
| #if defined(CONFIG_NUMA) |
| cpumask_t mask; |
| #endif |
| |
| LASSERT(index <= max - 1); |
| pc = &ptlrpcds->pd_threads[index]; |
| switch (ptlrpcd_bind_policy) { |
| case PDB_POLICY_NONE: |
| pc->pc_npartners = -1; |
| break; |
| case PDB_POLICY_FULL: |
| pc->pc_npartners = 0; |
| set_bit(LIOD_BIND, &pc->pc_flags); |
| break; |
| case PDB_POLICY_PAIR: |
| LASSERT(max % 2 == 0); |
| pc->pc_npartners = 1; |
| break; |
| case PDB_POLICY_NEIGHBOR: |
| #if defined(CONFIG_NUMA) |
| { |
| int i; |
| cpumask_copy(&mask, cpumask_of_node(cpu_to_node(index))); |
| for (i = max; i < num_online_cpus(); i++) |
| cpumask_clear_cpu(i, &mask); |
| pc->pc_npartners = cpumask_weight(&mask) - 1; |
| set_bit(LIOD_BIND, &pc->pc_flags); |
| } |
| #else |
| LASSERT(max >= 3); |
| pc->pc_npartners = 2; |
| #endif |
| break; |
| default: |
| CERROR("unknown ptlrpcd bind policy %d\n", ptlrpcd_bind_policy); |
| rc = -EINVAL; |
| } |
| |
| if (rc == 0 && pc->pc_npartners > 0) { |
| pc->pc_partners = kcalloc(pc->pc_npartners, |
| sizeof(struct ptlrpcd_ctl *), |
| GFP_NOFS); |
| if (pc->pc_partners == NULL) { |
| pc->pc_npartners = 0; |
| rc = -ENOMEM; |
| } else { |
| switch (ptlrpcd_bind_policy) { |
| case PDB_POLICY_PAIR: |
| if (index & 0x1) { |
| set_bit(LIOD_BIND, &pc->pc_flags); |
| pc->pc_partners[0] = &ptlrpcds-> |
| pd_threads[index - 1]; |
| ptlrpcds->pd_threads[index - 1]. |
| pc_partners[0] = pc; |
| } |
| break; |
| case PDB_POLICY_NEIGHBOR: |
| #if defined(CONFIG_NUMA) |
| { |
| struct ptlrpcd_ctl *ppc; |
| int i, pidx; |
| /* partners are cores in the same NUMA node. |
| * setup partnership only with ptlrpcd threads |
| * that are already initialized |
| */ |
| for (pidx = 0, i = 0; i < index; i++) { |
| if (cpumask_test_cpu(i, &mask)) { |
| ppc = &ptlrpcds->pd_threads[i]; |
| pc->pc_partners[pidx++] = ppc; |
| ppc->pc_partners[ppc-> |
| pc_npartners++] = pc; |
| } |
| } |
| /* adjust number of partners to the number |
| * of partnership really setup */ |
| pc->pc_npartners = pidx; |
| } |
| #else |
| if (index & 0x1) |
| set_bit(LIOD_BIND, &pc->pc_flags); |
| if (index > 0) { |
| pc->pc_partners[0] = &ptlrpcds-> |
| pd_threads[index - 1]; |
| ptlrpcds->pd_threads[index - 1]. |
| pc_partners[1] = pc; |
| if (index == max - 1) { |
| pc->pc_partners[1] = |
| &ptlrpcds->pd_threads[0]; |
| ptlrpcds->pd_threads[0]. |
| pc_partners[0] = pc; |
| } |
| } |
| #endif |
| break; |
| } |
| } |
| } |
| |
| return rc; |
| } |
| |
| |
| int ptlrpcd_start(int index, int max, const char *name, struct ptlrpcd_ctl *pc) |
| { |
| int rc; |
| |
| /* |
| * Do not allow start second thread for one pc. |
| */ |
| if (test_and_set_bit(LIOD_START, &pc->pc_flags)) { |
| CWARN("Starting second thread (%s) for same pc %p\n", |
| name, pc); |
| return 0; |
| } |
| |
| pc->pc_index = index; |
| init_completion(&pc->pc_starting); |
| init_completion(&pc->pc_finishing); |
| spin_lock_init(&pc->pc_lock); |
| strlcpy(pc->pc_name, name, sizeof(pc->pc_name)); |
| pc->pc_set = ptlrpc_prep_set(); |
| if (pc->pc_set == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| /* |
| * So far only "client" ptlrpcd uses an environment. In the future, |
| * ptlrpcd thread (or a thread-set) has to be given an argument, |
| * describing its "scope". |
| */ |
| rc = lu_context_init(&pc->pc_env.le_ctx, LCT_CL_THREAD|LCT_REMEMBER); |
| if (rc != 0) |
| goto out_set; |
| |
| { |
| struct task_struct *task; |
| if (index >= 0) { |
| rc = ptlrpcd_bind(index, max); |
| if (rc < 0) |
| goto out_env; |
| } |
| |
| task = kthread_run(ptlrpcd, pc, "%s", pc->pc_name); |
| if (IS_ERR(task)) { |
| rc = PTR_ERR(task); |
| goto out_env; |
| } |
| |
| wait_for_completion(&pc->pc_starting); |
| } |
| return 0; |
| |
| out_env: |
| lu_context_fini(&pc->pc_env.le_ctx); |
| |
| out_set: |
| if (pc->pc_set != NULL) { |
| struct ptlrpc_request_set *set = pc->pc_set; |
| |
| spin_lock(&pc->pc_lock); |
| pc->pc_set = NULL; |
| spin_unlock(&pc->pc_lock); |
| ptlrpc_set_destroy(set); |
| } |
| clear_bit(LIOD_BIND, &pc->pc_flags); |
| |
| out: |
| clear_bit(LIOD_START, &pc->pc_flags); |
| return rc; |
| } |
| |
| void ptlrpcd_stop(struct ptlrpcd_ctl *pc, int force) |
| { |
| if (!test_bit(LIOD_START, &pc->pc_flags)) { |
| CWARN("Thread for pc %p was not started\n", pc); |
| return; |
| } |
| |
| set_bit(LIOD_STOP, &pc->pc_flags); |
| if (force) |
| set_bit(LIOD_FORCE, &pc->pc_flags); |
| wake_up(&pc->pc_set->set_waitq); |
| } |
| |
| void ptlrpcd_free(struct ptlrpcd_ctl *pc) |
| { |
| struct ptlrpc_request_set *set = pc->pc_set; |
| |
| if (!test_bit(LIOD_START, &pc->pc_flags)) { |
| CWARN("Thread for pc %p was not started\n", pc); |
| goto out; |
| } |
| |
| wait_for_completion(&pc->pc_finishing); |
| lu_context_fini(&pc->pc_env.le_ctx); |
| |
| spin_lock(&pc->pc_lock); |
| pc->pc_set = NULL; |
| spin_unlock(&pc->pc_lock); |
| ptlrpc_set_destroy(set); |
| |
| clear_bit(LIOD_START, &pc->pc_flags); |
| clear_bit(LIOD_STOP, &pc->pc_flags); |
| clear_bit(LIOD_FORCE, &pc->pc_flags); |
| clear_bit(LIOD_BIND, &pc->pc_flags); |
| |
| out: |
| if (pc->pc_npartners > 0) { |
| LASSERT(pc->pc_partners != NULL); |
| |
| kfree(pc->pc_partners); |
| pc->pc_partners = NULL; |
| } |
| pc->pc_npartners = 0; |
| } |
| |
| static void ptlrpcd_fini(void) |
| { |
| int i; |
| |
| if (ptlrpcds != NULL) { |
| for (i = 0; i < ptlrpcds->pd_nthreads; i++) |
| ptlrpcd_stop(&ptlrpcds->pd_threads[i], 0); |
| for (i = 0; i < ptlrpcds->pd_nthreads; i++) |
| ptlrpcd_free(&ptlrpcds->pd_threads[i]); |
| ptlrpcd_stop(&ptlrpcds->pd_thread_rcv, 0); |
| ptlrpcd_free(&ptlrpcds->pd_thread_rcv); |
| kfree(ptlrpcds); |
| ptlrpcds = NULL; |
| } |
| } |
| |
| static int ptlrpcd_init(void) |
| { |
| int nthreads = num_online_cpus(); |
| char name[16]; |
| int size, i = -1, j, rc = 0; |
| |
| if (max_ptlrpcds > 0 && max_ptlrpcds < nthreads) |
| nthreads = max_ptlrpcds; |
| if (nthreads < 2) |
| nthreads = 2; |
| if (nthreads < 3 && ptlrpcd_bind_policy == PDB_POLICY_NEIGHBOR) |
| ptlrpcd_bind_policy = PDB_POLICY_PAIR; |
| else if (nthreads % 2 != 0 && ptlrpcd_bind_policy == PDB_POLICY_PAIR) |
| nthreads &= ~1; /* make sure it is even */ |
| |
| size = offsetof(struct ptlrpcd, pd_threads[nthreads]); |
| ptlrpcds = kzalloc(size, GFP_NOFS); |
| if (!ptlrpcds) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| snprintf(name, sizeof(name), "ptlrpcd_rcv"); |
| set_bit(LIOD_RECOVERY, &ptlrpcds->pd_thread_rcv.pc_flags); |
| rc = ptlrpcd_start(-1, nthreads, name, &ptlrpcds->pd_thread_rcv); |
| if (rc < 0) |
| goto out; |
| |
| /* XXX: We start nthreads ptlrpc daemons. Each of them can process any |
| * non-recovery async RPC to improve overall async RPC efficiency. |
| * |
| * But there are some issues with async I/O RPCs and async non-I/O |
| * RPCs processed in the same set under some cases. The ptlrpcd may |
| * be blocked by some async I/O RPC(s), then will cause other async |
| * non-I/O RPC(s) can not be processed in time. |
| * |
| * Maybe we should distinguish blocked async RPCs from non-blocked |
| * async RPCs, and process them in different ptlrpcd sets to avoid |
| * unnecessary dependency. But how to distribute async RPCs load |
| * among all the ptlrpc daemons becomes another trouble. */ |
| for (i = 0; i < nthreads; i++) { |
| snprintf(name, sizeof(name), "ptlrpcd_%d", i); |
| rc = ptlrpcd_start(i, nthreads, name, &ptlrpcds->pd_threads[i]); |
| if (rc < 0) |
| goto out; |
| } |
| |
| ptlrpcds->pd_size = size; |
| ptlrpcds->pd_index = 0; |
| ptlrpcds->pd_nthreads = nthreads; |
| |
| out: |
| if (rc != 0 && ptlrpcds != NULL) { |
| for (j = 0; j <= i; j++) |
| ptlrpcd_stop(&ptlrpcds->pd_threads[j], 0); |
| for (j = 0; j <= i; j++) |
| ptlrpcd_free(&ptlrpcds->pd_threads[j]); |
| ptlrpcd_stop(&ptlrpcds->pd_thread_rcv, 0); |
| ptlrpcd_free(&ptlrpcds->pd_thread_rcv); |
| kfree(ptlrpcds); |
| ptlrpcds = NULL; |
| } |
| |
| return 0; |
| } |
| |
| int ptlrpcd_addref(void) |
| { |
| int rc = 0; |
| |
| mutex_lock(&ptlrpcd_mutex); |
| if (++ptlrpcd_users == 1) |
| rc = ptlrpcd_init(); |
| mutex_unlock(&ptlrpcd_mutex); |
| return rc; |
| } |
| EXPORT_SYMBOL(ptlrpcd_addref); |
| |
| void ptlrpcd_decref(void) |
| { |
| mutex_lock(&ptlrpcd_mutex); |
| if (--ptlrpcd_users == 0) |
| ptlrpcd_fini(); |
| mutex_unlock(&ptlrpcd_mutex); |
| } |
| EXPORT_SYMBOL(ptlrpcd_decref); |
| /** @} ptlrpcd */ |