xref: /onnv-gate/usr/src/lib/libumem/common/umem_update_thread.c (revision 6812:febeba71273d)
10Sstevel@tonic-gate /*
20Sstevel@tonic-gate  * CDDL HEADER START
30Sstevel@tonic-gate  *
40Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
54258Sbarts  * Common Development and Distribution License (the "License").
64258Sbarts  * You may not use this file except in compliance with the License.
70Sstevel@tonic-gate  *
80Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
90Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
100Sstevel@tonic-gate  * See the License for the specific language governing permissions
110Sstevel@tonic-gate  * and limitations under the License.
120Sstevel@tonic-gate  *
130Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
140Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
150Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
160Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
170Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
180Sstevel@tonic-gate  *
190Sstevel@tonic-gate  * CDDL HEADER END
200Sstevel@tonic-gate  */
21*5891Sraf 
220Sstevel@tonic-gate /*
23*5891Sraf  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
240Sstevel@tonic-gate  * Use is subject to license terms.
250Sstevel@tonic-gate  */
260Sstevel@tonic-gate 
270Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
280Sstevel@tonic-gate 
290Sstevel@tonic-gate #include "umem_base.h"
300Sstevel@tonic-gate #include "vmem_base.h"
310Sstevel@tonic-gate 
320Sstevel@tonic-gate #include <signal.h>
330Sstevel@tonic-gate 
340Sstevel@tonic-gate /*ARGSUSED*/
350Sstevel@tonic-gate static void *
umem_update_thread(void * arg)360Sstevel@tonic-gate umem_update_thread(void *arg)
370Sstevel@tonic-gate {
380Sstevel@tonic-gate 	struct timeval now;
390Sstevel@tonic-gate 	int in_update = 0;
400Sstevel@tonic-gate 
410Sstevel@tonic-gate 	(void) mutex_lock(&umem_update_lock);
420Sstevel@tonic-gate 
430Sstevel@tonic-gate 	ASSERT(umem_update_thr == thr_self());
440Sstevel@tonic-gate 	ASSERT(umem_st_update_thr == 0);
450Sstevel@tonic-gate 
460Sstevel@tonic-gate 	for (;;) {
470Sstevel@tonic-gate 		umem_process_updates();
480Sstevel@tonic-gate 
490Sstevel@tonic-gate 		if (in_update) {
500Sstevel@tonic-gate 			in_update = 0;
510Sstevel@tonic-gate 			/*
520Sstevel@tonic-gate 			 * we wait until now to set the next update time
530Sstevel@tonic-gate 			 * so that the updates are self-throttling
540Sstevel@tonic-gate 			 */
550Sstevel@tonic-gate 			(void) gettimeofday(&umem_update_next, NULL);
560Sstevel@tonic-gate 			umem_update_next.tv_sec += umem_reap_interval;
570Sstevel@tonic-gate 		}
580Sstevel@tonic-gate 
590Sstevel@tonic-gate 		switch (umem_reaping) {
600Sstevel@tonic-gate 		case UMEM_REAP_DONE:
610Sstevel@tonic-gate 		case UMEM_REAP_ADDING:
620Sstevel@tonic-gate 			break;
630Sstevel@tonic-gate 
640Sstevel@tonic-gate 		case UMEM_REAP_ACTIVE:
650Sstevel@tonic-gate 			umem_reap_next = gethrtime() +
660Sstevel@tonic-gate 			    (hrtime_t)umem_reap_interval * NANOSEC;
670Sstevel@tonic-gate 			umem_reaping = UMEM_REAP_DONE;
680Sstevel@tonic-gate 			break;
690Sstevel@tonic-gate 
700Sstevel@tonic-gate 		default:
710Sstevel@tonic-gate 			ASSERT(umem_reaping == UMEM_REAP_DONE ||
720Sstevel@tonic-gate 			    umem_reaping == UMEM_REAP_ADDING ||
730Sstevel@tonic-gate 			    umem_reaping == UMEM_REAP_ACTIVE);
740Sstevel@tonic-gate 			break;
750Sstevel@tonic-gate 		}
760Sstevel@tonic-gate 
770Sstevel@tonic-gate 		(void) gettimeofday(&now, NULL);
780Sstevel@tonic-gate 		if (now.tv_sec > umem_update_next.tv_sec ||
790Sstevel@tonic-gate 		    (now.tv_sec == umem_update_next.tv_sec &&
800Sstevel@tonic-gate 		    now.tv_usec >= umem_update_next.tv_usec)) {
810Sstevel@tonic-gate 			/*
820Sstevel@tonic-gate 			 * Time to run an update
830Sstevel@tonic-gate 			 */
840Sstevel@tonic-gate 			(void) mutex_unlock(&umem_update_lock);
850Sstevel@tonic-gate 
860Sstevel@tonic-gate 			vmem_update(NULL);
870Sstevel@tonic-gate 			/*
880Sstevel@tonic-gate 			 * umem_cache_update can use umem_add_update to
890Sstevel@tonic-gate 			 * request further work.  The update is not complete
900Sstevel@tonic-gate 			 * until all such work is finished.
910Sstevel@tonic-gate 			 */
920Sstevel@tonic-gate 			umem_cache_applyall(umem_cache_update);
930Sstevel@tonic-gate 
940Sstevel@tonic-gate 			(void) mutex_lock(&umem_update_lock);
950Sstevel@tonic-gate 			in_update = 1;
960Sstevel@tonic-gate 			continue;	/* start processing immediately */
970Sstevel@tonic-gate 		}
980Sstevel@tonic-gate 
990Sstevel@tonic-gate 		/*
1000Sstevel@tonic-gate 		 * if there is no work to do, we wait until it is time for
1010Sstevel@tonic-gate 		 * next update, or someone wakes us.
1020Sstevel@tonic-gate 		 */
1030Sstevel@tonic-gate 		if (umem_null_cache.cache_unext == &umem_null_cache) {
104*5891Sraf 			int cancel_state;
1050Sstevel@tonic-gate 			timespec_t abs_time;
1060Sstevel@tonic-gate 			abs_time.tv_sec = umem_update_next.tv_sec;
1070Sstevel@tonic-gate 			abs_time.tv_nsec = umem_update_next.tv_usec * 1000;
1080Sstevel@tonic-gate 
109*5891Sraf 			(void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE,
110*5891Sraf 			    &cancel_state);
111*5891Sraf 			(void) cond_timedwait(&umem_update_cv,
1120Sstevel@tonic-gate 			    &umem_update_lock, &abs_time);
113*5891Sraf 			(void) pthread_setcancelstate(cancel_state, NULL);
1140Sstevel@tonic-gate 		}
1150Sstevel@tonic-gate 	}
1164261Sbarts 	/* LINTED no return statement */
1170Sstevel@tonic-gate }
1180Sstevel@tonic-gate 
1190Sstevel@tonic-gate int
umem_create_update_thread(void)1200Sstevel@tonic-gate umem_create_update_thread(void)
1210Sstevel@tonic-gate {
1220Sstevel@tonic-gate 	sigset_t sigmask, oldmask;
1234258Sbarts 	thread_t newthread;
1240Sstevel@tonic-gate 
1250Sstevel@tonic-gate 	ASSERT(MUTEX_HELD(&umem_update_lock));
1260Sstevel@tonic-gate 	ASSERT(umem_update_thr == 0);
1270Sstevel@tonic-gate 
1280Sstevel@tonic-gate 	/*
1290Sstevel@tonic-gate 	 * The update thread handles no signals
1300Sstevel@tonic-gate 	 */
1310Sstevel@tonic-gate 	(void) sigfillset(&sigmask);
1320Sstevel@tonic-gate 	(void) thr_sigsetmask(SIG_BLOCK, &sigmask, &oldmask);
1334258Sbarts 
1344258Sbarts 	/*
1354258Sbarts 	 * drop the umem_update_lock; we cannot hold locks acquired in
1364258Sbarts 	 * pre-fork handler while calling thr_create or thr_continue().
1374258Sbarts 	 */
1384258Sbarts 
1394258Sbarts 	(void) mutex_unlock(&umem_update_lock);
1404258Sbarts 
1410Sstevel@tonic-gate 	if (thr_create(NULL, NULL, umem_update_thread, NULL,
1424258Sbarts 	    THR_BOUND | THR_DAEMON | THR_DETACHED | THR_SUSPENDED,
1434258Sbarts 	    &newthread) == 0) {
1440Sstevel@tonic-gate 		(void) thr_sigsetmask(SIG_SETMASK, &oldmask, NULL);
1454258Sbarts 
1464258Sbarts 		(void) mutex_lock(&umem_update_lock);
1474258Sbarts 		/*
1484258Sbarts 		 * due to the locking in umem_reap(), only one thread can
1494258Sbarts 		 * ever call umem_create_update_thread() at a time.  This
1504258Sbarts 		 * must be the case for this code to work.
1514258Sbarts 		 */
1524258Sbarts 
1534258Sbarts 		ASSERT(umem_update_thr == 0);
1544258Sbarts 		umem_update_thr = newthread;
1554258Sbarts 		(void) mutex_unlock(&umem_update_lock);
1564258Sbarts 		(void) thr_continue(newthread);
1574258Sbarts 		(void) mutex_lock(&umem_update_lock);
1584258Sbarts 
1590Sstevel@tonic-gate 		return (1);
1604258Sbarts 	} else { /* thr_create failed */
1614258Sbarts 		(void) thr_sigsetmask(SIG_SETMASK, &oldmask, NULL);
1624258Sbarts 		(void) mutex_lock(&umem_update_lock);
1630Sstevel@tonic-gate 	}
1640Sstevel@tonic-gate 	return (0);
1650Sstevel@tonic-gate }
166