X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;ds=sidebyside;f=lustre%2Fldlm%2Fldlm_inodebits.c;h=74119fb5e3be4189efda4a2c738b28d6b7987757;hb=49fd10ec8a2a85bbc56618d70f2f71d323d90a4c;hp=2223d58e34b8369d91d4c8f1d772f302d0c08e04;hpb=8c83e7d75989ef527e43a824a0dbe46bffabd07d;p=fs%2Flustre-release.git diff --git a/lustre/ldlm/ldlm_inodebits.c b/lustre/ldlm/ldlm_inodebits.c index 2223d58..74119fb 100644 --- a/lustre/ldlm/ldlm_inodebits.c +++ b/lustre/ldlm/ldlm_inodebits.c @@ -1,6 +1,4 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: - * +/* * GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. @@ -29,8 +27,7 @@ * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * - * Copyright (c) 2011 Whamcloud, Inc. - * + * Copyright (c) 2011, 2013, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -42,83 +39,122 @@ * Author: Phil Schwan */ +/** + * This file contains implementation of IBITS lock type + * + * IBITS lock type contains a bit mask determining various properties of an + * object. The meanings of specific bits are specific to the caller and are + * opaque to LDLM code. + * + * Locks with intersecting bitmasks and conflicting lock modes (e.g. LCK_PW) + * are considered conflicting. See the lock mode compatibility matrix + * in lustre_dlm.h. + */ + #define DEBUG_SUBSYSTEM S_LDLM -#ifndef __KERNEL__ -# include -#endif #include #include #include +#include #include "ldlm_internal.h" -/* Determine if the lock is compatible with all locks on the queue. */ +#ifdef HAVE_SERVER_SUPPORT +/** + * Determine if the lock is compatible with all locks on the queue. + * + * If \a work_list is provided, conflicting locks are linked there. + * If \a work_list is not provided, we exit this function on first conflict. + * + * \retval 0 if there are conflicting locks in the \a queue + * \retval 1 if the lock is compatible to all locks in \a queue + * + * IBITS locks in granted queue are organized in bunches of + * same-mode/same-bits locks called "skip lists". The First lock in the + * bunch contains a pointer to the end of the bunch. This allows us to + * skip an entire bunch when iterating the list in search for conflicting + * locks if first lock of the bunch is not conflicting with us. + */ static int -ldlm_inodebits_compat_queue(cfs_list_t *queue, struct ldlm_lock *req, - cfs_list_t *work_list) +ldlm_inodebits_compat_queue(struct list_head *queue, struct ldlm_lock *req, + struct list_head *work_list) { - cfs_list_t *tmp; - struct ldlm_lock *lock; - ldlm_mode_t req_mode = req->l_req_mode; - __u64 req_bits = req->l_policy_data.l_inodebits.bits; - int compat = 1; - ENTRY; - - LASSERT(req_bits); /* There is no sense in lock with no bits set, - I think. Also such a lock would be compatible - with any other bit lock */ - - cfs_list_for_each(tmp, queue) { - cfs_list_t *mode_tail; - - lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link); - - if (req == lock) - RETURN(compat); - - /* last lock in mode group */ - LASSERT(lock->l_sl_mode.prev != NULL); - mode_tail = &cfs_list_entry(lock->l_sl_mode.prev, - struct ldlm_lock, - l_sl_mode)->l_res_link; - - /* locks are compatible, bits don't matter */ - if (lockmode_compat(lock->l_req_mode, req_mode)) { - /* jump to last lock in mode group */ - tmp = mode_tail; - continue; - } - - for (;;) { - cfs_list_t *head; - - /* last lock in policy group */ - tmp = &cfs_list_entry(lock->l_sl_policy.prev, - struct ldlm_lock, - l_sl_policy)->l_res_link; - - /* locks with bits overlapped are conflicting locks */ - if (lock->l_policy_data.l_inodebits.bits & req_bits) { - /* COS lock from the same client is - not conflicting */ - if (lock->l_req_mode == LCK_COS && - lock->l_client_cookie == req->l_client_cookie) - goto not_conflicting; - /* conflicting policy */ - if (!work_list) - RETURN(0); - - compat = 0; - - /* add locks of the policy group to - * @work_list as blocking locks for - * @req */ + struct list_head *tmp; + struct ldlm_lock *lock; + __u64 req_bits = req->l_policy_data.l_inodebits.bits; + int compat = 1; + ENTRY; + + /* There is no sense in lock with no bits set, I think. + * Also, such a lock would be compatible with any other bit lock */ + LASSERT(req_bits != 0); + + list_for_each(tmp, queue) { + struct list_head *mode_tail; + + lock = list_entry(tmp, struct ldlm_lock, l_res_link); + + /* We stop walking the queue if we hit ourselves so we don't + * take conflicting locks enqueued after us into account, + * or we'd wait forever. */ + if (req == lock) + RETURN(compat); + + /* last lock in mode group */ + LASSERT(lock->l_sl_mode.prev != NULL); + mode_tail = &list_entry(lock->l_sl_mode.prev, + struct ldlm_lock, + l_sl_mode)->l_res_link; + + /* if reqest lock is not COS_INCOMPAT and COS is disabled, + * they are compatible, IOW this request is from a local + * transaction on a DNE system. */ + if (lock->l_req_mode == LCK_COS && !ldlm_is_cos_incompat(req) && + !ldlm_is_cos_enabled(req)) { + /* jump to last lock in mode group */ + tmp = mode_tail; + continue; + } + + /* locks' mode are compatible, bits don't matter */ + if (lockmode_compat(lock->l_req_mode, req->l_req_mode)) { + /* jump to last lock in mode group */ + tmp = mode_tail; + continue; + } + + for (;;) { + struct list_head *head; + + /* Advance loop cursor to last lock in policy group. */ + tmp = &list_entry(lock->l_sl_policy.prev, + struct ldlm_lock, + l_sl_policy)->l_res_link; + + /* Locks with overlapping bits conflict. */ + if (lock->l_policy_data.l_inodebits.bits & req_bits) { + /* COS lock mode has a special compatibility + * requirement: it is only compatible with + * locks from the same client. */ + if (lock->l_req_mode == LCK_COS && + !ldlm_is_cos_incompat(req) && + ldlm_is_cos_enabled(req) && + lock->l_client_cookie == req->l_client_cookie) + goto not_conflicting; + /* Found a conflicting policy group. */ + if (!work_list) + RETURN(0); + + compat = 0; + + /* Add locks of the policy group to @work_list + * as blocking locks for @req */ if (lock->l_blocking_ast) ldlm_add_ast_work_item(lock, req, work_list); head = &lock->l_sl_policy; - cfs_list_for_each_entry(lock, head, l_sl_policy) + list_for_each_entry(lock, head, l_sl_policy) if (lock->l_blocking_ast) ldlm_add_ast_work_item(lock, req, work_list); @@ -128,35 +164,49 @@ ldlm_inodebits_compat_queue(cfs_list_t *queue, struct ldlm_lock *req, break; tmp = tmp->next; - lock = cfs_list_entry(tmp, struct ldlm_lock, + lock = list_entry(tmp, struct ldlm_lock, l_res_link); - } /* loop over policy groups within one mode group */ - } /* loop over mode groups within @queue */ + } /* Loop over policy groups within one mode group. */ + } /* Loop over mode groups within @queue. */ - RETURN(compat); + RETURN(compat); } -/* If first_enq is 0 (ie, called from ldlm_reprocess_queue): - * - blocking ASTs have already been sent - * - must call this function with the ns lock held - * - * If first_enq is 1 (ie, called from ldlm_lock_enqueue): - * - blocking ASTs have not been sent - * - must call this function with the ns lock held once */ -int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags, - int first_enq, ldlm_error_t *err, - cfs_list_t *work_list) +/** + * Process a granting attempt for IBITS lock. + * Must be called with ns lock held + * + * This function looks for any conflicts for \a lock in the granted or + * waiting queues. The lock is granted if no conflicts are found in + * either queue. + * + * If \a first_enq is 0 (ie, called from ldlm_reprocess_queue): + * - blocking ASTs have already been sent + * + * If \a first_enq is 1 (ie, called from ldlm_lock_enqueue): + * - blocking ASTs have not been sent yet, so list of conflicting locks + * would be collected and ASTs sent. + */ +int ldlm_process_inodebits_lock(struct ldlm_lock *lock, __u64 *flags, + int first_enq, enum ldlm_error *err, + struct list_head *work_list) { - struct ldlm_resource *res = lock->l_resource; - CFS_LIST_HEAD(rpc_list); - int rc; - ENTRY; + struct ldlm_resource *res = lock->l_resource; + struct list_head rpc_list; + int rc; + ENTRY; - LASSERT(cfs_list_empty(&res->lr_converting)); - check_res_locked(res); + LASSERT(lock->l_granted_mode != lock->l_req_mode); + LASSERT(list_empty(&res->lr_converting)); + INIT_LIST_HEAD(&rpc_list); + check_res_locked(res); + + /* (*flags & LDLM_FL_BLOCK_NOWAIT) is for layout lock right now. */ + if (!first_enq || (*flags & LDLM_FL_BLOCK_NOWAIT)) { + *err = ELDLM_LOCK_ABORTED; + if (*flags & LDLM_FL_BLOCK_NOWAIT) + *err = ELDLM_LOCK_WOULDBLOCK; - if (!first_enq) { - LASSERT(work_list != NULL); rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, NULL); if (!rc) RETURN(LDLM_ITER_STOP); @@ -166,8 +216,10 @@ int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags, ldlm_resource_unlink_lock(lock); ldlm_grant_lock(lock, work_list); - RETURN(LDLM_ITER_CONTINUE); - } + + *err = ELDLM_OK; + RETURN(LDLM_ITER_CONTINUE); + } restart: rc = ldlm_inodebits_compat_queue(&res->lr_granted, lock, &rpc_list); @@ -180,14 +232,14 @@ int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags, * bug 2322: we used to unlink and re-add here, which was a * terrible folly -- if we goto restart, we could get * re-ordered! Causes deadlock, because ASTs aren't sent! */ - if (cfs_list_empty(&lock->l_res_link)) + if (list_empty(&lock->l_res_link)) ldlm_resource_add_lock(res, &res->lr_waiting, lock); unlock_res(res); rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list, LDLM_WORK_BL_AST); lock_res(res); - if (rc == -ERESTART) - GOTO(restart, -ERESTART); + if (rc == -ERESTART) + GOTO(restart, rc); *flags |= LDLM_FL_BLOCK_GRANTED; } else { ldlm_resource_unlink_lock(lock); @@ -195,17 +247,18 @@ int ldlm_process_inodebits_lock(struct ldlm_lock *lock, int *flags, } RETURN(0); } +#endif /* HAVE_SERVER_SUPPORT */ -void ldlm_ibits_policy_wire_to_local(const ldlm_wire_policy_data_t *wpolicy, - ldlm_policy_data_t *lpolicy) +void ldlm_ibits_policy_wire_to_local(const union ldlm_wire_policy_data *wpolicy, + union ldlm_policy_data *lpolicy) { - memset(lpolicy, 0, sizeof(*lpolicy)); - lpolicy->l_inodebits.bits = wpolicy->l_inodebits.bits; + memset(lpolicy, 0, sizeof(*lpolicy)); + lpolicy->l_inodebits.bits = wpolicy->l_inodebits.bits; } -void ldlm_ibits_policy_local_to_wire(const ldlm_policy_data_t *lpolicy, - ldlm_wire_policy_data_t *wpolicy) +void ldlm_ibits_policy_local_to_wire(const union ldlm_policy_data *lpolicy, + union ldlm_wire_policy_data *wpolicy) { - memset(wpolicy, 0, sizeof(*wpolicy)); - wpolicy->l_inodebits.bits = lpolicy->l_inodebits.bits; + memset(wpolicy, 0, sizeof(*wpolicy)); + wpolicy->l_inodebits.bits = lpolicy->l_inodebits.bits; }