X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;ds=sidebyside;f=lnet%2Flnet%2Flib-eq.c;h=e4b544d077141ffd6342f156633b5a4f10519989;hb=d517440d54715a37d4b29e9e6076391bec33e423;hp=5bae602fa88efd61097f6564ae07a61faf13efb1;hpb=4bb7537c493db080b914fc6201a9c9835c7eefcb;p=fs%2Flustre-release.git diff --git a/lnet/lnet/lib-eq.c b/lnet/lnet/lib-eq.c index 5bae602..e4b544d 100644 --- a/lnet/lnet/lib-eq.c +++ b/lnet/lnet/lib-eq.c @@ -1,42 +1,81 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: +/* + * GPL HEADER START * - * lib/lib-eq.c - * Library level Event queue management routines + * 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). * - * Copyright (c) 2001-2003 Cluster File Systems, Inc. + * 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 * - * This file is part of Lustre, http://www.lustre.org + * 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. * - * 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. + * GPL HEADER END + */ +/* + * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. * - * 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. + * lnet/lnet/lib-eq.c * - * 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. + * Library level Event queue management routines */ #define DEBUG_SUBSYSTEM S_LNET #include +/** + * Create an event queue that has room for \a count number of events. + * + * The event queue is circular and older events will be overwritten by new + * ones if they are not removed in time by the user using the functions + * LNetEQGet(), LNetEQWait(), or LNetEQPoll(). It is up to the user to + * determine the appropriate size of the event queue to prevent this loss + * of events. Note that when EQ handler is specified in \a callback, no + * event loss can happen, since the handler is run for each event deposited + * into the EQ. + * + * \param count The number of events to be stored in the event queue. It + * will be rounded up to the next power of two. + * \param callback A handler function that runs when an event is deposited + * into the EQ. The constant value LNET_EQ_HANDLER_NONE can be used to + * indicate that no event handler is desired. + * \param handle On successful return, this location will hold a handle for + * the newly created EQ. + * + * \retval 0 On success. + * \retval -EINVAL If an parameter is not valid. + * \retval -ENOMEM If memory for the EQ can't be allocated. + * + * \see lnet_eq_handler_t for the discussion on EQ handler semantics. + */ int -LNetEQAlloc(unsigned int count, lnet_eq_handler_t callback, +LNetEQAlloc(unsigned int count, lnet_eq_handler_t callback, lnet_handle_eq_t *handle) { lnet_eq_t *eq; LASSERT (the_lnet.ln_init); LASSERT (the_lnet.ln_refcount > 0); - + /* We need count to be a power of 2 so that when eq_{enq,deq}_seq * overflow, they don't skip entries, so the queue has the same - * apparant capacity at all times */ + * apparent capacity at all times */ if (count != LOWEST_BIT_SET(count)) { /* not a power of 2 already */ do { /* knock off all but the top bit... */ @@ -48,7 +87,7 @@ LNetEQAlloc(unsigned int count, lnet_eq_handler_t callback, if (count == 0) /* catch bad parameter / overflow on roundup */ return (-EINVAL); - + eq = lnet_eq_alloc(); if (eq == NULL) return (-ENOMEM); @@ -75,7 +114,7 @@ LNetEQAlloc(unsigned int count, lnet_eq_handler_t callback, LNET_LOCK(); lnet_initialise_handle (&eq->eq_lh, LNET_COOKIE_TYPE_EQ); - list_add (&eq->eq_list, &the_lnet.ln_active_eqs); + cfs_list_add (&eq->eq_list, &the_lnet.ln_active_eqs); LNET_UNLOCK(); @@ -83,6 +122,16 @@ LNetEQAlloc(unsigned int count, lnet_eq_handler_t callback, return (0); } +/** + * Release the resources associated with an event queue if it's idle; + * otherwise do nothing and it's up to the user to try again. + * + * \param eqh A handle for the event queue to be released. + * + * \retval 0 If the EQ is not in use and freed. + * \retval -ENOENT If \a eqh does not point to a valid EQ. + * \retval -EBUSY If the EQ is still in use by some MDs. + */ int LNetEQFree(lnet_handle_eq_t eqh) { @@ -92,7 +141,7 @@ LNetEQFree(lnet_handle_eq_t eqh) LASSERT (the_lnet.ln_init); LASSERT (the_lnet.ln_refcount > 0); - + LNET_LOCK(); eq = lnet_handle2eq(&eqh); @@ -102,6 +151,8 @@ LNetEQFree(lnet_handle_eq_t eqh) } if (eq->eq_refcount != 0) { + CDEBUG(D_NET, "Event queue (%d) busy on destroy.\n", + eq->eq_refcount); LNET_UNLOCK(); return (-EBUSY); } @@ -111,7 +162,7 @@ LNetEQFree(lnet_handle_eq_t eqh) size = eq->eq_size; lnet_invalidate_handle (&eq->eq_lh); - list_del (&eq->eq_list); + cfs_list_del (&eq->eq_list); lnet_eq_free (eq); LNET_UNLOCK(); @@ -154,16 +205,47 @@ lib_get_event (lnet_eq_t *eq, lnet_event_t *ev) RETURN(rc); } - +/** + * A nonblocking function that can be used to get the next event in an EQ. + * If an event handler is associated with the EQ, the handler will run before + * this function returns successfully. The event is removed from the queue. + * + * \param eventq A handle for the event queue. + * \param event On successful return (1 or -EOVERFLOW), this location will + * hold the next event in the EQ. + * + * \retval 0 No pending event in the EQ. + * \retval 1 Indicates success. + * \retval -ENOENT If \a eventq does not point to a valid EQ. + * \retval -EOVERFLOW Indicates success (i.e., an event is returned) and that + * at least one event between this event and the last event obtained from the + * EQ has been dropped due to limited space in the EQ. + */ int LNetEQGet (lnet_handle_eq_t eventq, lnet_event_t *event) { int which; - return LNetEQPoll(&eventq, 1, 0, + return LNetEQPoll(&eventq, 1, 0, event, &which); } +/** + * Block the calling process until there is an event in the EQ. + * If an event handler is associated with the EQ, the handler will run before + * this function returns successfully. This function returns the next event + * in the EQ and removes it from the EQ. + * + * \param eventq A handle for the event queue. + * \param event On successful return (1 or -EOVERFLOW), this location will + * hold the next event in the EQ. + * + * \retval 1 Indicates success. + * \retval -ENOENT If \a eventq does not point to a valid EQ. + * \retval -EOVERFLOW Indicates success (i.e., an event is returned) and that + * at least one event between this event and the last event obtained from the + * EQ has been dropped due to limited space in the EQ. + */ int LNetEQWait (lnet_handle_eq_t eventq, lnet_event_t *event) { @@ -173,6 +255,32 @@ LNetEQWait (lnet_handle_eq_t eventq, lnet_event_t *event) event, &which); } +/** + * Block the calling process until there's an event from a set of EQs or + * timeout happens. + * + * If an event handler is associated with the EQ, the handler will run before + * this function returns successfully, in which case the corresponding event + * is consumed. + * + * LNetEQPoll() provides a timeout to allow applications to poll, block for a + * fixed period, or block indefinitely. + * + * \param eventqs,neq An array of EQ handles, and size of the array. + * \param timeout_ms Time in milliseconds to wait for an event to occur on + * one of the EQs. The constant LNET_TIME_FOREVER can be used to indicate an + * infinite timeout. + * \param event,which On successful return (1 or -EOVERFLOW), \a event will + * hold the next event in the EQs, and \a which will contain the index of the + * EQ from which the event was taken. + * + * \retval 0 No pending event in the EQs after timeout. + * \retval 1 Indicates success. + * \retval -EOVERFLOW Indicates success (i.e., an event is returned) and that + * at least one event between this event and the last event obtained from the + * EQ indicated by \a which has been dropped due to limited space in the EQ. + * \retval -ENOENT If there's an invalid handle in \a eventqs. + */ int LNetEQPoll (lnet_handle_eq_t *eventqs, int neq, int timeout_ms, lnet_event_t *event, int *which) @@ -201,6 +309,16 @@ LNetEQPoll (lnet_handle_eq_t *eventqs, int neq, int timeout_ms, LNET_LOCK(); for (;;) { +#ifndef __KERNEL__ + LNET_UNLOCK(); + + /* Recursion breaker */ + if (the_lnet.ln_rc_state == LNET_RC_STATE_RUNNING && + !LNetHandleIsEqual(eventqs[0], the_lnet.ln_rc_eqh)) + lnet_router_checker(); + + LNET_LOCK(); +#endif for (i = 0; i < neq; i++) { lnet_eq_t *eq = lnet_handle2eq(&eventqs[i]); @@ -216,34 +334,34 @@ LNetEQPoll (lnet_handle_eq_t *eventqs, int neq, int timeout_ms, RETURN(rc); } } - + #ifdef __KERNEL__ if (timeout_ms == 0) { - LNET_UNLOCK (); + LNET_UNLOCK(); RETURN (0); } cfs_waitlink_init(&wl); - set_current_state(TASK_INTERRUPTIBLE); + cfs_set_current_state(CFS_TASK_INTERRUPTIBLE); cfs_waitq_add(&the_lnet.ln_waitq, &wl); LNET_UNLOCK(); if (timeout_ms < 0) { cfs_waitq_wait (&wl, CFS_TASK_INTERRUPTIBLE); - } else { + } else { struct timeval tv; now = cfs_time_current(); cfs_waitq_timedwait(&wl, CFS_TASK_INTERRUPTIBLE, cfs_time_seconds(timeout_ms)/1000); - cfs_duration_usec(cfs_time_sub(cfs_time_current(), now), - &tv); - timeout_ms -= tv.tv_sec * 1000 + tv.tv_usec / 1000; + cfs_duration_usec(cfs_time_sub(cfs_time_current(), now), + &tv); + timeout_ms -= (int)(tv.tv_sec * 1000 + tv.tv_usec / 1000); if (timeout_ms < 0) timeout_ms = 0; } - + LNET_LOCK(); cfs_waitq_del(&the_lnet.ln_waitq, &wl); #else @@ -259,7 +377,7 @@ LNetEQPoll (lnet_handle_eq_t *eventqs, int neq, int timeout_ms, gettimeofday(&then, NULL); (eqwaitni->ni_lnd->lnd_wait)(eqwaitni, timeout_ms); - + gettimeofday(&now, NULL); timeout_ms -= (now.tv_sec - then.tv_sec) * 1000 + (now.tv_usec - then.tv_usec) / 1000; @@ -289,26 +407,26 @@ LNetEQPoll (lnet_handle_eq_t *eventqs, int neq, int timeout_ms, LBUG(); # else if (timeout_ms < 0) { - pthread_cond_wait(&the_lnet.ln_cond, + pthread_cond_wait(&the_lnet.ln_cond, &the_lnet.ln_lock); } else { gettimeofday(&then, NULL); - + ts.tv_sec = then.tv_sec + timeout_ms/1000; - ts.tv_nsec = then.tv_usec * 1000 + + ts.tv_nsec = then.tv_usec * 1000 + (timeout_ms%1000) * 1000000; if (ts.tv_nsec >= 1000000000) { ts.tv_sec++; ts.tv_nsec -= 1000000000; } - + pthread_cond_timedwait(&the_lnet.ln_cond, &the_lnet.ln_lock, &ts); - + gettimeofday(&now, NULL); timeout_ms -= (now.tv_sec - then.tv_sec) * 1000 + (now.tv_usec - then.tv_usec) / 1000; - + if (timeout_ms < 0) timeout_ms = 0; }