-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
+/*
+ * GPL HEADER START
*
- * Copyright (C) 2001-2003 Cluster File Systems, Inc.
- * Author Peter Braam <braam@clusterfs.com>
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
- * This file is part of Lustre, http://www.lustre.org.
+ * 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.
*
- * Lustre is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License 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).
*
- * Lustre 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 for more details.
+ * 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
*
- * You should have received a copy of the GNU General Public License
- * along with Lustre; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 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
#ifdef __KERNEL__
-# include <linux/version.h>
-# include <linux/module.h>
-# include <linux/mm.h>
-# include <linux/highmem.h>
-# include <linux/lustre_dlm.h>
-# if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0))
-# include <linux/workqueue.h>
-# include <linux/smp_lock.h>
-# else
-# include <linux/locks.h>
-# endif
-# include <linux/ctype.h>
-# include <linux/init.h>
+# include <libcfs/libcfs.h>
#else /* __KERNEL__ */
# include <liblustre.h>
# include <ctype.h>
#endif
-#include <linux/kp30.h>
-#include <linux/lustre_net.h>
-
-#include <linux/lustre_ha.h>
-#include <linux/obd_support.h> /* for OBD_FAIL_CHECK */
-#include <linux/lprocfs_status.h>
-
-#define LIOD_STOP 0
-struct ptlrpcd_ctl {
- unsigned long pc_flags;
- spinlock_t pc_lock;
- struct completion pc_starting;
- struct completion pc_finishing;
- struct list_head pc_req_list;
- wait_queue_head_t pc_waitq;
- struct ptlrpc_request_set *pc_set;
- char pc_name[16];
-#ifndef __KERNEL__
- int pc_recurred;
- void *pc_callback;
-#endif
+#include <lustre_net.h>
+# include <lustre_lib.h>
+
+#include <lustre_ha.h>
+#include <obd_class.h> /* for obd_zombie */
+#include <obd_support.h> /* for OBD_FAIL_CHECK */
+#include <cl_object.h> /* cl_env_{get,put}() */
+#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 struct ptlrpcd_ctl ptlrpcd_pc;
-static struct ptlrpcd_ctl ptlrpcd_recovery_pc;
+#ifdef __KERNEL__
+static int max_ptlrpcds;
+CFS_MODULE_PARM(max_ptlrpcds, "i", int, 0644,
+ "Max ptlrpcd thread count to be started.");
+
+static int ptlrpcd_bind_policy = PDB_POLICY_PAIR;
+CFS_MODULE_PARM(ptlrpcd_bind_policy, "i", int, 0644,
+ "Ptlrpcd threads binding mode.");
+#endif
+static struct ptlrpcd *ptlrpcds;
-static DECLARE_MUTEX(ptlrpcd_sem);
+struct mutex ptlrpcd_mutex;
static int ptlrpcd_users = 0;
void ptlrpcd_wake(struct ptlrpc_request *req)
{
- struct ptlrpcd_ctl *pc = req->rq_ptlrpcd_data;
+ struct ptlrpc_request_set *rq_set = req->rq_set;
+
+ LASSERT(rq_set != NULL);
+
+ cfs_waitq_signal(&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;
- LASSERT(pc != NULL);
+ if (req != NULL && req->rq_send_state != LUSTRE_IMP_FULL)
+ return &ptlrpcds->pd_thread_rcv;
- wake_up(&pc->pc_waitq);
+#ifdef __KERNEL__
+ switch (policy) {
+ case PDL_POLICY_SAME:
+ idx = cfs_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 < cfs_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 == cfs_smp_processor_id())
+ idx++;
+ idx %= ptlrpcds->pd_nthreads;
+ ptlrpcds->pd_index = idx;
+ break;
+ }
+#endif /* __KERNEL__ */
+
+ return &ptlrpcds->pd_threads[idx];
}
-void ptlrpcd_add_req(struct ptlrpc_request *req)
+/**
+ * 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)
{
+ cfs_list_t *tmp, *pos;
+#ifdef __KERNEL__
struct ptlrpcd_ctl *pc;
+ struct ptlrpc_request_set *new;
+ int count, i;
- if (req->rq_send_state == LUSTRE_IMP_FULL)
- pc = &ptlrpcd_pc;
- else
- pc = &ptlrpcd_recovery_pc;
+ pc = ptlrpcd_select_pc(NULL, PDL_POLICY_LOCAL, -1);
+ new = pc->pc_set;
+#endif
- do_gettimeofday(&req->rq_rpcd_start);
- ptlrpc_set_add_new_req(pc->pc_set, req);
- req->rq_ptlrpcd_data = pc;
-
- ptlrpcd_wake(req);
+ cfs_list_for_each_safe(pos, tmp, &set->set_requests) {
+ struct ptlrpc_request *req =
+ cfs_list_entry(pos, struct ptlrpc_request,
+ rq_set_chain);
+
+ LASSERT(req->rq_phase == RQ_PHASE_NEW);
+#ifdef __KERNEL__
+ req->rq_set = new;
+ req->rq_queued_time = cfs_time_current();
+#else
+ cfs_list_del_init(&req->rq_set_chain);
+ req->rq_set = NULL;
+ ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
+ cfs_atomic_dec(&set->set_remaining);
+#endif
+ }
+
+#ifdef __KERNEL__
+ spin_lock(&new->set_new_req_lock);
+ cfs_list_splice_init(&set->set_requests, &new->set_new_requests);
+ i = cfs_atomic_read(&set->set_remaining);
+ count = cfs_atomic_add_return(i, &new->set_new_count);
+ cfs_atomic_set(&set->set_remaining, 0);
+ spin_unlock(&new->set_new_req_lock);
+ if (count == i) {
+ cfs_waitq_signal(&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++)
+ cfs_waitq_signal(&pc->pc_partners[i]->pc_set->set_waitq);
+ }
+#endif
}
+EXPORT_SYMBOL(ptlrpcd_add_rqset);
-static int ptlrpcd_check(struct ptlrpcd_ctl *pc)
+#ifdef __KERNEL__
+/**
+ * Return transferred RPCs count.
+ */
+static int ptlrpcd_steal_rqset(struct ptlrpc_request_set *des,
+ struct ptlrpc_request_set *src)
{
- struct list_head *tmp, *pos;
+ cfs_list_t *tmp, *pos;
struct ptlrpc_request *req;
- unsigned long flags;
int rc = 0;
- ENTRY;
- if (test_bit(LIOD_STOP, &pc->pc_flags))
- RETURN(1);
+ spin_lock(&src->set_new_req_lock);
+ if (likely(!cfs_list_empty(&src->set_new_requests))) {
+ cfs_list_for_each_safe(pos, tmp, &src->set_new_requests) {
+ req = cfs_list_entry(pos, struct ptlrpc_request,
+ rq_set_chain);
+ req->rq_set = des;
+ }
+ cfs_list_splice_init(&src->set_new_requests,
+ &des->set_requests);
+ rc = cfs_atomic_read(&src->set_new_count);
+ cfs_atomic_add(rc, &des->set_remaining);
+ cfs_atomic_set(&src->set_new_count, 0);
+ }
+ spin_unlock(&src->set_new_req_lock);
+ return rc;
+}
+#endif
+
+/**
+ * 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 vaid "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 */
+ cfs_atomic_inc(&req->rq_set->set_remaining);
+ spin_unlock(&req->rq_lock);
+ cfs_waitq_signal(&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)
+{
+ cfs_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)
+{
+ cfs_list_t *tmp, *pos;
+ struct ptlrpc_request *req;
+ struct ptlrpc_request_set *set = pc->pc_set;
+ int rc = 0;
+ int rc2;
+ ENTRY;
- spin_lock_irqsave(&pc->pc_set->set_new_req_lock, flags);
- list_for_each_safe(pos, tmp, &pc->pc_set->set_new_requests) {
- req = list_entry(pos, struct ptlrpc_request, rq_set_chain);
- list_del_init(&req->rq_set_chain);
- ptlrpc_set_add_req(pc->pc_set, req);
- rc = 1; /* need to calculate its timeout */
+ if (cfs_atomic_read(&set->set_new_count)) {
+ spin_lock(&set->set_new_req_lock);
+ if (likely(!cfs_list_empty(&set->set_new_requests))) {
+ cfs_list_splice_init(&set->set_new_requests,
+ &set->set_requests);
+ cfs_atomic_add(cfs_atomic_read(&set->set_new_count),
+ &set->set_remaining);
+ cfs_atomic_set(&set->set_new_count, 0);
+ /*
+ * Need to calculate its timeout.
+ */
+ rc = 1;
+ }
+ spin_unlock(&set->set_new_req_lock);
}
- spin_unlock_irqrestore(&pc->pc_set->set_new_req_lock, flags);
- if (pc->pc_set->set_remaining) {
- rc = rc | ptlrpc_check_set(pc->pc_set);
+ /* 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);
+ }
- /* XXX our set never completes, so we prune the completed
- * reqs after each iteration. boy could this be smarter. */
- list_for_each_safe(pos, tmp, &pc->pc_set->set_requests) {
- req = list_entry(pos, struct ptlrpc_request,
- rq_set_chain);
+ if (cfs_atomic_read(&set->set_remaining))
+ rc |= ptlrpc_check_set(env, set);
+
+ if (!cfs_list_empty(&set->set_requests)) {
+ /*
+ * XXX: our set never completes, so we prune the completed
+ * reqs after each iteration. boy could this be smarter.
+ */
+ cfs_list_for_each_safe(pos, tmp, &set->set_requests) {
+ req = cfs_list_entry(pos, struct ptlrpc_request,
+ rq_set_chain);
if (req->rq_phase != RQ_PHASE_COMPLETE)
continue;
- list_del_init(&req->rq_set_chain);
+ cfs_list_del_init(&req->rq_set_chain);
req->rq_set = NULL;
- ptlrpc_req_finished (req);
+ ptlrpc_req_finished(req);
}
}
+
if (rc == 0) {
- /* If new requests have been added, make sure to wake up */
- spin_lock_irqsave(&pc->pc_set->set_new_req_lock, flags);
- rc = !list_empty(&pc->pc_set->set_new_requests);
- spin_unlock_irqrestore(&pc->pc_set->set_new_req_lock, flags);
+ /*
+ * If new requests have been added, make sure to wake up.
+ */
+ rc = cfs_atomic_read(&set->set_new_count);
+
+#ifdef __KERNEL__
+ /* 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 (cfs_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);
+ }
+#endif
}
+
RETURN(rc);
}
#ifdef __KERNEL__
-/* ptlrpc's code paths like to execute in process context, so we have this
- * thread which spins on a set which contains the io rpcs. llite specifies
- * ptlrpcd's set when it pushes pages down into the oscs */
+/**
+ * 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;
- unsigned long flags;
+ struct ptlrpc_request_set *set = pc->pc_set;
+ struct lu_env env = { .le_ses = NULL };
+ int rc, exit = 0;
ENTRY;
- kportal_daemonize(pc->pc_name);
-
- SIGNAL_MASK_LOCK(current, flags);
- sigfillset(¤t->blocked);
- RECALC_SIGPENDING;
- SIGNAL_MASK_UNLOCK(current, flags);
-
- complete(&pc->pc_starting);
-
- /* 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. */
- while (1) {
- wait_queue_t set_wait;
+ cfs_daemonize_ctxt(pc->pc_name);
+#if defined(CONFIG_SMP) && \
+(defined(HAVE_CPUMASK_OF_NODE) || defined(HAVE_NODE_TO_CPUMASK))
+ if (test_bit(LIOD_BIND, &pc->pc_flags)) {
+ int index = pc->pc_index;
+
+ if (index >= 0 && index < cfs_num_possible_cpus()) {
+ while (!cpu_online(index)) {
+ if (++index >= cfs_num_possible_cpus())
+ index = 0;
+ }
+ cfs_set_cpus_allowed(cfs_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(pc->pc_set) * HZ;
- lwi = LWI_TIMEOUT(timeout, ptlrpc_expired_set, pc->pc_set);
+ 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++;
+ }
- /* ala the pinger, wait on pc's waitqueue and the set's */
- init_waitqueue_entry(&set_wait, current);
- add_wait_queue(&pc->pc_set->set_waitq, &set_wait);
- l_wait_event(pc->pc_waitq, ptlrpcd_check(pc), &lwi);
- remove_wait_queue(&pc->pc_set->set_waitq, &set_wait);
+ /*
+ * 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 (!cfs_list_empty(&set->set_requests))
+ ptlrpc_set_wait(set);
+ lu_context_fini(&env.le_ctx);
+
+ complete(&pc->pc_finishing);
- if (test_bit(LIOD_STOP, &pc->pc_flags))
- break;
- }
- /* wait for inflight requests to drain */
- if (!list_empty(&pc->pc_set->set_requests))
- ptlrpc_set_wait(pc->pc_set);
- 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 threds 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) && \
+(defined(HAVE_CPUMASK_OF_NODE) || defined(HAVE_NODE_TO_CPUMASK))
+ cpumask_t mask;
+#endif
+ ENTRY;
+
+ 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) && \
+(defined(HAVE_CPUMASK_OF_NODE) || defined(HAVE_NODE_TO_CPUMASK))
+ {
+ int i;
+ mask = *cpumask_of_node(cpu_to_node(index));
+ for (i = max; i < cfs_num_online_cpus(); i++)
+ cpu_clear(i, mask);
+ pc->pc_npartners = cpus_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) {
+ OBD_ALLOC(pc->pc_partners,
+ sizeof(struct ptlrpcd_ctl *) * pc->pc_npartners);
+ 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) && \
+(defined(HAVE_CPUMASK_OF_NODE) || defined(HAVE_NODE_TO_CPUMASK))
+ {
+ 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 (cpu_isset(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);
+}
+
+#else /* !__KERNEL__ */
+
+/**
+ * In liblustre we do not have separate threads, so this function
+ * is called from time to time all across common code to see
+ * if something needs to be processed on ptlrpcd set.
+ */
int ptlrpcd_check_async_rpcs(void *arg)
{
struct ptlrpcd_ctl *pc = arg;
- int rc = 0;
+ int rc = 0;
- /* single threaded!! */
+ /*
+ * Single threaded!!
+ */
pc->pc_recurred++;
if (pc->pc_recurred == 1) {
- rc = ptlrpcd_check(pc);
- if (!rc)
- ptlrpc_expired_set(pc->pc_set);
+ rc = lu_env_refill(&pc->pc_env);
+ if (rc == 0) {
+ lu_context_enter(&pc->pc_env.le_ctx);
+ rc = ptlrpcd_check(&pc->pc_env, pc);
+ if (!rc)
+ ptlrpc_expired_set(pc->pc_set);
+ /*
+ * XXX: send replay requests.
+ */
+ if (test_bit(LIOD_RECOVERY, &pc->pc_flags))
+ rc = ptlrpcd_check(&pc->pc_env, pc);
+ lu_context_exit(&pc->pc_env.le_ctx);
+ }
}
pc->pc_recurred--;
return rc;
}
-#endif
-static int ptlrpcd_start(char *name, struct ptlrpcd_ctl *pc)
+int ptlrpcd_idle(void *arg)
{
- int rc = 0;
+ struct ptlrpcd_ctl *pc = arg;
- memset(pc, 0, sizeof(*pc));
- init_completion(&pc->pc_starting);
- init_completion(&pc->pc_finishing);
- init_waitqueue_head(&pc->pc_waitq);
- pc->pc_flags = 0;
- spin_lock_init(&pc->pc_lock);
- INIT_LIST_HEAD(&pc->pc_req_list);
- snprintf (pc->pc_name, sizeof (pc->pc_name), name);
+ return (cfs_atomic_read(&pc->pc_set->set_new_count) == 0 &&
+ cfs_atomic_read(&pc->pc_set->set_remaining) == 0);
+}
+#endif
+
+int ptlrpcd_start(int index, int max, const char *name, struct ptlrpcd_ctl *pc)
+{
+ int rc;
+ int env = 0;
+ ENTRY;
+
+ /*
+ * 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);
+ strncpy(pc->pc_name, name, sizeof(pc->pc_name) - 1);
pc->pc_set = ptlrpc_prep_set();
if (pc->pc_set == NULL)
GOTO(out, rc = -ENOMEM);
+ /*
+ * 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, rc);
+ env = 1;
#ifdef __KERNEL__
- if (kernel_thread(ptlrpcd, pc, 0) < 0) {
- ptlrpc_set_destroy(pc->pc_set);
- GOTO(out, rc = -ECHILD);
+ if (index >= 0) {
+ rc = ptlrpcd_bind(index, max);
+ if (rc < 0)
+ GOTO(out, rc);
}
- wait_for_completion(&pc->pc_starting);
+ rc = cfs_create_thread(ptlrpcd, pc, 0);
+ if (rc < 0)
+ GOTO(out, rc);
+
+ rc = 0;
+ wait_for_completion(&pc->pc_starting);
#else
- pc->pc_callback =
- liblustre_register_wait_callback(&ptlrpcd_check_async_rpcs, pc);
+ pc->pc_wait_callback =
+ liblustre_register_wait_callback("ptlrpcd_check_async_rpcs",
+ &ptlrpcd_check_async_rpcs, pc);
+ pc->pc_idle_callback =
+ liblustre_register_idle_callback("ptlrpcd_check_idle_rpcs",
+ &ptlrpcd_idle, pc);
#endif
out:
- RETURN(rc);
+ if (rc) {
+#ifdef __KERNEL__
+ 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);
+ }
+ if (env != 0)
+ lu_context_fini(&pc->pc_env.le_ctx);
+ clear_bit(LIOD_BIND, &pc->pc_flags);
+#else
+ SET_BUT_UNUSED(env);
+#endif
+ clear_bit(LIOD_START, &pc->pc_flags);
+ }
+ RETURN(rc);
}
-static void ptlrpcd_stop(struct ptlrpcd_ctl *pc)
+void ptlrpcd_stop(struct ptlrpcd_ctl *pc, int force)
{
- set_bit(LIOD_STOP, &pc->pc_flags);
- wake_up(&pc->pc_waitq);
+ ENTRY;
+
+ if (!test_bit(LIOD_START, &pc->pc_flags)) {
+ CWARN("Thread for pc %p was not started\n", pc);
+ goto out;
+ }
+
+ set_bit(LIOD_STOP, &pc->pc_flags);
+ if (force)
+ set_bit(LIOD_FORCE, &pc->pc_flags);
+ cfs_waitq_signal(&pc->pc_set->set_waitq);
+
+out:
+ EXIT;
+}
+
+void ptlrpcd_free(struct ptlrpcd_ctl *pc)
+{
+ struct ptlrpc_request_set *set = pc->pc_set;
+ ENTRY;
+
+ if (!test_bit(LIOD_START, &pc->pc_flags)) {
+ CWARN("Thread for pc %p was not started\n", pc);
+ goto out;
+ }
+
#ifdef __KERNEL__
- wait_for_completion(&pc->pc_finishing);
+ wait_for_completion(&pc->pc_finishing);
#else
- liblustre_deregister_wait_callback(pc->pc_callback);
+ liblustre_deregister_wait_callback(pc->pc_wait_callback);
+ liblustre_deregister_idle_callback(pc->pc_idle_callback);
#endif
- ptlrpc_set_destroy(pc->pc_set);
+ 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:
+#ifdef __KERNEL__
+ if (pc->pc_npartners > 0) {
+ LASSERT(pc->pc_partners != NULL);
+
+ OBD_FREE(pc->pc_partners,
+ sizeof(struct ptlrpcd_ctl *) * pc->pc_npartners);
+ pc->pc_partners = NULL;
+ }
+ pc->pc_npartners = 0;
+#endif
+ EXIT;
}
-int ptlrpcd_addref(void)
+static void ptlrpcd_fini(void)
{
- int rc = 0;
+ int i;
+ ENTRY;
+
+ 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);
+ OBD_FREE(ptlrpcds, ptlrpcds->pd_size);
+ ptlrpcds = NULL;
+ }
+
+ EXIT;
+}
+
+static int ptlrpcd_init(void)
+{
+ int nthreads = cfs_num_online_cpus();
+ char name[16];
+ int size, i = -1, j, rc = 0;
ENTRY;
- down(&ptlrpcd_sem);
- if (++ptlrpcd_users != 1)
- GOTO(out, rc);
+#ifdef __KERNEL__
+ 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 */
+#else
+ nthreads = 1;
+#endif
- rc = ptlrpcd_start("ptlrpcd", &ptlrpcd_pc);
- if (rc) {
- --ptlrpcd_users;
- GOTO(out, rc);
- }
+ size = offsetof(struct ptlrpcd, pd_threads[nthreads]);
+ OBD_ALLOC(ptlrpcds, size);
+ if (ptlrpcds == NULL)
+ GOTO(out, rc = -ENOMEM);
- rc = ptlrpcd_start("ptlrpcd-recov", &ptlrpcd_recovery_pc);
- if (rc) {
- ptlrpcd_stop(&ptlrpcd_pc);
- --ptlrpcd_users;
+ snprintf(name, 15, "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, rc);
+
+ /* 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, 15, "ptlrpcd_%d", i);
+ rc = ptlrpcd_start(i, nthreads, name, &ptlrpcds->pd_threads[i]);
+ if (rc < 0)
+ GOTO(out, rc);
}
+
+ ptlrpcds->pd_size = size;
+ ptlrpcds->pd_index = 0;
+ ptlrpcds->pd_nthreads = nthreads;
+
out:
- up(&ptlrpcd_sem);
+ 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);
+ OBD_FREE(ptlrpcds, size);
+ ptlrpcds = NULL;
+ }
+
+ RETURN(0);
+}
+
+int ptlrpcd_addref(void)
+{
+ int rc = 0;
+ ENTRY;
+
+ 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)
{
- down(&ptlrpcd_sem);
- if (--ptlrpcd_users == 0) {
- ptlrpcd_stop(&ptlrpcd_pc);
- ptlrpcd_stop(&ptlrpcd_recovery_pc);
- }
- up(&ptlrpcd_sem);
+ mutex_lock(&ptlrpcd_mutex);
+ if (--ptlrpcd_users == 0)
+ ptlrpcd_fini();
+ mutex_unlock(&ptlrpcd_mutex);
}
+EXPORT_SYMBOL(ptlrpcd_decref);
+/** @} ptlrpcd */
git://git.whamcloud.com / fs / lustre-release.git / blobdiff