lustre/ptlrpc/sec_gc.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  30  * Use is subject to license terms.
  31  *
  32  * Copyright (c) 2012, Whamcloud, Inc.
  33  */
  34 /*
  35  * This file is part of Lustre, http://www.lustre.org/
  36  * Lustre is a trademark of Sun Microsystems, Inc.
  37  *
  38  * lustre/ptlrpc/sec_gc.c
  39  *
  40  * Author: Eric Mei <ericm@clusterfs.com>
  41  */
  42
  43 #ifndef EXPORT_SYMTAB
  44 # define EXPORT_SYMTAB
  45 #endif
  46 #define DEBUG_SUBSYSTEM S_SEC
  47
  48 #ifndef __KERNEL__
  49 #include <liblustre.h>
  50 #else
  51 #include <libcfs/libcfs.h>
  52 #endif
  53
  54 #include <obd_support.h>
  55 #include <obd_class.h>
  56 #include <lustre_net.h>
  57 #include <lustre_sec.h>
  58
  59 #define SEC_GC_INTERVAL (30 * 60)
  60
  61 #ifdef __KERNEL__
  62
  63 static cfs_mutex_t sec_gc_mutex;
  64 static CFS_LIST_HEAD(sec_gc_list);
  65 static cfs_spinlock_t sec_gc_list_lock;
  66
  67 static CFS_LIST_HEAD(sec_gc_ctx_list);
  68 static cfs_spinlock_t sec_gc_ctx_list_lock;
  69
  70 static struct ptlrpc_thread sec_gc_thread;
  71 static cfs_atomic_t sec_gc_wait_del = CFS_ATOMIC_INIT(0);
  72
  73
  74 void sptlrpc_gc_add_sec(struct ptlrpc_sec *sec)
  75 {
  76         LASSERT(sec->ps_policy->sp_cops->gc_ctx);
  77         LASSERT(sec->ps_gc_interval > 0);
  78         LASSERT(cfs_list_empty(&sec->ps_gc_list));
  79
  80         sec->ps_gc_next = cfs_time_current_sec() + sec->ps_gc_interval;
  81
  82         cfs_spin_lock(&sec_gc_list_lock);
  83         cfs_list_add_tail(&sec_gc_list, &sec->ps_gc_list);
  84         cfs_spin_unlock(&sec_gc_list_lock);
  85
  86         CDEBUG(D_SEC, "added sec %p(%s)\n", sec, sec->ps_policy->sp_name);
  87 }
  88 EXPORT_SYMBOL(sptlrpc_gc_add_sec);
  89
  90 void sptlrpc_gc_del_sec(struct ptlrpc_sec *sec)
  91 {
  92         if (cfs_list_empty(&sec->ps_gc_list))
  93                 return;
  94
  95         cfs_might_sleep();
  96
  97         /* signal before list_del to make iteration in gc thread safe */
  98         cfs_atomic_inc(&sec_gc_wait_del);
  99
 100         cfs_spin_lock(&sec_gc_list_lock);
 101         cfs_list_del_init(&sec->ps_gc_list);
 102         cfs_spin_unlock(&sec_gc_list_lock);
 103
 104         /* barrier */
 105         cfs_mutex_lock(&sec_gc_mutex);
 106         cfs_mutex_unlock(&sec_gc_mutex);
 107
 108         cfs_atomic_dec(&sec_gc_wait_del);
 109
 110         CDEBUG(D_SEC, "del sec %p(%s)\n", sec, sec->ps_policy->sp_name);
 111 }
 112 EXPORT_SYMBOL(sptlrpc_gc_del_sec);
 113
 114 void sptlrpc_gc_add_ctx(struct ptlrpc_cli_ctx *ctx)
 115 {
 116         LASSERT(cfs_list_empty(&ctx->cc_gc_chain));
 117
 118         CDEBUG(D_SEC, "hand over ctx %p(%u->%s)\n",
 119                ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec));
 120         cfs_spin_lock(&sec_gc_ctx_list_lock);
 121         cfs_list_add(&ctx->cc_gc_chain, &sec_gc_ctx_list);
 122         cfs_spin_unlock(&sec_gc_ctx_list_lock);
 123
 124         thread_add_flags(&sec_gc_thread, SVC_SIGNAL);
 125         cfs_waitq_signal(&sec_gc_thread.t_ctl_waitq);
 126 }
 127 EXPORT_SYMBOL(sptlrpc_gc_add_ctx);
 128
 129 static void sec_process_ctx_list(void)
 130 {
 131         struct ptlrpc_cli_ctx *ctx;
 132
 133         cfs_spin_lock(&sec_gc_ctx_list_lock);
 134
 135         while (!cfs_list_empty(&sec_gc_ctx_list)) {
 136                 ctx = cfs_list_entry(sec_gc_ctx_list.next,
 137                                      struct ptlrpc_cli_ctx, cc_gc_chain);
 138                 cfs_list_del_init(&ctx->cc_gc_chain);
 139                 cfs_spin_unlock(&sec_gc_ctx_list_lock);
 140
 141                 LASSERT(ctx->cc_sec);
 142                 LASSERT(cfs_atomic_read(&ctx->cc_refcount) == 1);
 143                 CDEBUG(D_SEC, "gc pick up ctx %p(%u->%s)\n",
 144                        ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec));
 145                 sptlrpc_cli_ctx_put(ctx, 1);
 146
 147                 cfs_spin_lock(&sec_gc_ctx_list_lock);
 148         }
 149
 150         cfs_spin_unlock(&sec_gc_ctx_list_lock);
 151 }
 152
 153 static void sec_do_gc(struct ptlrpc_sec *sec)
 154 {
 155         LASSERT(sec->ps_policy->sp_cops->gc_ctx);
 156
 157         if (unlikely(sec->ps_gc_next == 0)) {
 158                 CDEBUG(D_SEC, "sec %p(%s) has 0 gc time\n",
 159                       sec, sec->ps_policy->sp_name);
 160                 return;
 161         }
 162
 163         CDEBUG(D_SEC, "check on sec %p(%s)\n", sec, sec->ps_policy->sp_name);
 164
 165         if (cfs_time_after(sec->ps_gc_next, cfs_time_current_sec()))
 166                 return;
 167
 168         sec->ps_policy->sp_cops->gc_ctx(sec);
 169         sec->ps_gc_next = cfs_time_current_sec() + sec->ps_gc_interval;
 170 }
 171
 172 static int sec_gc_main(void *arg)
 173 {
 174         struct ptlrpc_thread *thread = (struct ptlrpc_thread *) arg;
 175         struct l_wait_info    lwi;
 176
 177         cfs_daemonize_ctxt("sptlrpc_gc");
 178
 179         /* Record that the thread is running */
 180         thread_set_flags(thread, SVC_RUNNING);
 181         cfs_waitq_signal(&thread->t_ctl_waitq);
 182
 183         while (1) {
 184                 struct ptlrpc_sec *sec;
 185
 186                 thread_clear_flags(thread, SVC_SIGNAL);
 187                 sec_process_ctx_list();
 188 again:
 189                 /* go through sec list do gc.
 190                  * FIXME here we iterate through the whole list each time which
 191                  * is not optimal. we perhaps want to use balanced binary tree
 192                  * to trace each sec as order of expiry time.
 193                  * another issue here is we wakeup as fixed interval instead of
 194                  * according to each sec's expiry time */
 195                 cfs_mutex_lock(&sec_gc_mutex);
 196                 cfs_list_for_each_entry(sec, &sec_gc_list, ps_gc_list) {
 197                         /* if someone is waiting to be deleted, let it
 198                          * proceed as soon as possible. */
 199                         if (cfs_atomic_read(&sec_gc_wait_del)) {
 200                                 CDEBUG(D_SEC, "deletion pending, start over\n");
 201                                 cfs_mutex_unlock(&sec_gc_mutex);
 202                                 goto again;
 203                         }
 204
 205                         sec_do_gc(sec);
 206                 }
 207                 cfs_mutex_unlock(&sec_gc_mutex);
 208
 209                 /* check ctx list again before sleep */
 210                 sec_process_ctx_list();
 211
 212                 lwi = LWI_TIMEOUT(SEC_GC_INTERVAL * CFS_HZ, NULL, NULL);
 213                 l_wait_event(thread->t_ctl_waitq,
 214                              thread_is_stopping(thread) ||
 215                              thread_is_signal(thread),
 216                              &lwi);
 217
 218                 if (thread_test_and_clear_flags(thread, SVC_STOPPING))
 219                         break;
 220         }
 221
 222         thread_set_flags(thread, SVC_STOPPED);
 223         cfs_waitq_signal(&thread->t_ctl_waitq);
 224         return 0;
 225 }
 226
 227 int sptlrpc_gc_init(void)
 228 {
 229         struct l_wait_info lwi = { 0 };
 230         int                rc;
 231
 232         cfs_mutex_init(&sec_gc_mutex);
 233         cfs_spin_lock_init(&sec_gc_list_lock);
 234         cfs_spin_lock_init(&sec_gc_ctx_list_lock);
 235
 236         /* initialize thread control */
 237         memset(&sec_gc_thread, 0, sizeof(sec_gc_thread));
 238         cfs_waitq_init(&sec_gc_thread.t_ctl_waitq);
 239
 240         rc = cfs_create_thread(sec_gc_main, &sec_gc_thread, CFS_DAEMON_FLAGS);
 241         if (rc < 0) {
 242                 CERROR("can't start gc thread: %d\n", rc);
 243                 return rc;
 244         }
 245
 246         l_wait_event(sec_gc_thread.t_ctl_waitq,
 247                      thread_is_running(&sec_gc_thread), &lwi);
 248         return 0;
 249 }
 250
 251 void sptlrpc_gc_fini(void)
 252 {
 253         struct l_wait_info lwi = { 0 };
 254
 255         thread_set_flags(&sec_gc_thread, SVC_STOPPING);
 256         cfs_waitq_signal(&sec_gc_thread.t_ctl_waitq);
 257
 258         l_wait_event(sec_gc_thread.t_ctl_waitq,
 259                      thread_is_stopped(&sec_gc_thread), &lwi);
 260 }
 261
 262 #else /* !__KERNEL__ */
 263
 264 void sptlrpc_gc_add_sec(struct ptlrpc_sec *sec)
 265 {
 266 }
 267 void sptlrpc_gc_del_sec(struct ptlrpc_sec *sec)
 268 {
 269 }
 270 int sptlrpc_gc_init(void)
 271 {
 272         return 0;
 273 }
 274 void sptlrpc_gc_fini(void)
 275 {
 276 }
 277
 278 #endif /* __KERNEL__ */