diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/ptlrpc/sec_gc.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/ptlrpc/sec_gc.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/ptlrpc/sec_gc.c b/drivers/staging/lustre/lustre/ptlrpc/sec_gc.c new file mode 100644 index 000000000000..4c96a14a1bb6 --- /dev/null +++ b/drivers/staging/lustre/lustre/ptlrpc/sec_gc.c @@ -0,0 +1,250 @@ +/* + * GPL HEADER START + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + * + * Copyright (c) 2011, 2012, Intel Corporation. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. + * + * lustre/ptlrpc/sec_gc.c + * + * Author: Eric Mei <ericm@clusterfs.com> + */ + +#define DEBUG_SUBSYSTEM S_SEC + +#include <linux/libcfs/libcfs.h> + +#include <obd_support.h> +#include <obd_class.h> +#include <lustre_net.h> +#include <lustre_sec.h> + +#define SEC_GC_INTERVAL (30 * 60) + + +static struct mutex sec_gc_mutex; +static LIST_HEAD(sec_gc_list); +static spinlock_t sec_gc_list_lock; + +static LIST_HEAD(sec_gc_ctx_list); +static spinlock_t sec_gc_ctx_list_lock; + +static struct ptlrpc_thread sec_gc_thread; +static atomic_t sec_gc_wait_del = ATOMIC_INIT(0); + + +void sptlrpc_gc_add_sec(struct ptlrpc_sec *sec) +{ + LASSERT(sec->ps_policy->sp_cops->gc_ctx); + LASSERT(sec->ps_gc_interval > 0); + LASSERT(list_empty(&sec->ps_gc_list)); + + sec->ps_gc_next = cfs_time_current_sec() + sec->ps_gc_interval; + + spin_lock(&sec_gc_list_lock); + list_add_tail(&sec_gc_list, &sec->ps_gc_list); + spin_unlock(&sec_gc_list_lock); + + CDEBUG(D_SEC, "added sec %p(%s)\n", sec, sec->ps_policy->sp_name); +} +EXPORT_SYMBOL(sptlrpc_gc_add_sec); + +void sptlrpc_gc_del_sec(struct ptlrpc_sec *sec) +{ + if (list_empty(&sec->ps_gc_list)) + return; + + might_sleep(); + + /* signal before list_del to make iteration in gc thread safe */ + atomic_inc(&sec_gc_wait_del); + + spin_lock(&sec_gc_list_lock); + list_del_init(&sec->ps_gc_list); + spin_unlock(&sec_gc_list_lock); + + /* barrier */ + mutex_lock(&sec_gc_mutex); + mutex_unlock(&sec_gc_mutex); + + atomic_dec(&sec_gc_wait_del); + + CDEBUG(D_SEC, "del sec %p(%s)\n", sec, sec->ps_policy->sp_name); +} +EXPORT_SYMBOL(sptlrpc_gc_del_sec); + +void sptlrpc_gc_add_ctx(struct ptlrpc_cli_ctx *ctx) +{ + LASSERT(list_empty(&ctx->cc_gc_chain)); + + CDEBUG(D_SEC, "hand over ctx %p(%u->%s)\n", + ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec)); + spin_lock(&sec_gc_ctx_list_lock); + list_add(&ctx->cc_gc_chain, &sec_gc_ctx_list); + spin_unlock(&sec_gc_ctx_list_lock); + + thread_add_flags(&sec_gc_thread, SVC_SIGNAL); + wake_up(&sec_gc_thread.t_ctl_waitq); +} +EXPORT_SYMBOL(sptlrpc_gc_add_ctx); + +static void sec_process_ctx_list(void) +{ + struct ptlrpc_cli_ctx *ctx; + + spin_lock(&sec_gc_ctx_list_lock); + + while (!list_empty(&sec_gc_ctx_list)) { + ctx = list_entry(sec_gc_ctx_list.next, + struct ptlrpc_cli_ctx, cc_gc_chain); + list_del_init(&ctx->cc_gc_chain); + spin_unlock(&sec_gc_ctx_list_lock); + + LASSERT(ctx->cc_sec); + LASSERT(atomic_read(&ctx->cc_refcount) == 1); + CDEBUG(D_SEC, "gc pick up ctx %p(%u->%s)\n", + ctx, ctx->cc_vcred.vc_uid, sec2target_str(ctx->cc_sec)); + sptlrpc_cli_ctx_put(ctx, 1); + + spin_lock(&sec_gc_ctx_list_lock); + } + + spin_unlock(&sec_gc_ctx_list_lock); +} + +static void sec_do_gc(struct ptlrpc_sec *sec) +{ + LASSERT(sec->ps_policy->sp_cops->gc_ctx); + + if (unlikely(sec->ps_gc_next == 0)) { + CDEBUG(D_SEC, "sec %p(%s) has 0 gc time\n", + sec, sec->ps_policy->sp_name); + return; + } + + CDEBUG(D_SEC, "check on sec %p(%s)\n", sec, sec->ps_policy->sp_name); + + if (cfs_time_after(sec->ps_gc_next, cfs_time_current_sec())) + return; + + sec->ps_policy->sp_cops->gc_ctx(sec); + sec->ps_gc_next = cfs_time_current_sec() + sec->ps_gc_interval; +} + +static int sec_gc_main(void *arg) +{ + struct ptlrpc_thread *thread = (struct ptlrpc_thread *) arg; + struct l_wait_info lwi; + + unshare_fs_struct(); + + /* Record that the thread is running */ + thread_set_flags(thread, SVC_RUNNING); + wake_up(&thread->t_ctl_waitq); + + while (1) { + struct ptlrpc_sec *sec; + + thread_clear_flags(thread, SVC_SIGNAL); + sec_process_ctx_list(); +again: + /* go through sec list do gc. + * FIXME here we iterate through the whole list each time which + * is not optimal. we perhaps want to use balanced binary tree + * to trace each sec as order of expiry time. + * another issue here is we wakeup as fixed interval instead of + * according to each sec's expiry time */ + mutex_lock(&sec_gc_mutex); + list_for_each_entry(sec, &sec_gc_list, ps_gc_list) { + /* if someone is waiting to be deleted, let it + * proceed as soon as possible. */ + if (atomic_read(&sec_gc_wait_del)) { + CDEBUG(D_SEC, "deletion pending, start over\n"); + mutex_unlock(&sec_gc_mutex); + goto again; + } + + sec_do_gc(sec); + } + mutex_unlock(&sec_gc_mutex); + + /* check ctx list again before sleep */ + sec_process_ctx_list(); + + lwi = LWI_TIMEOUT(SEC_GC_INTERVAL * HZ, NULL, NULL); + l_wait_event(thread->t_ctl_waitq, + thread_is_stopping(thread) || + thread_is_signal(thread), + &lwi); + + if (thread_test_and_clear_flags(thread, SVC_STOPPING)) + break; + } + + thread_set_flags(thread, SVC_STOPPED); + wake_up(&thread->t_ctl_waitq); + return 0; +} + +int sptlrpc_gc_init(void) +{ + struct l_wait_info lwi = { 0 }; + task_t *task; + + mutex_init(&sec_gc_mutex); + spin_lock_init(&sec_gc_list_lock); + spin_lock_init(&sec_gc_ctx_list_lock); + + /* initialize thread control */ + memset(&sec_gc_thread, 0, sizeof(sec_gc_thread)); + init_waitqueue_head(&sec_gc_thread.t_ctl_waitq); + + task = kthread_run(sec_gc_main, &sec_gc_thread, "sptlrpc_gc"); + if (IS_ERR(task)) { + CERROR("can't start gc thread: %ld\n", PTR_ERR(task)); + return PTR_ERR(task); + } + + l_wait_event(sec_gc_thread.t_ctl_waitq, + thread_is_running(&sec_gc_thread), &lwi); + return 0; +} + +void sptlrpc_gc_fini(void) +{ + struct l_wait_info lwi = { 0 }; + + thread_set_flags(&sec_gc_thread, SVC_STOPPING); + wake_up(&sec_gc_thread.t_ctl_waitq); + + l_wait_event(sec_gc_thread.t_ctl_waitq, + thread_is_stopped(&sec_gc_thread), &lwi); +} |