1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms
5 * of the Common Development and Distribution License
6 * (the "License").  You may not use this file except
7 * in compliance with the License.
8 *
9 * You can obtain a copy of the license at
10 * src/OPENSOLARIS.LICENSE
11 * or http://www.opensolaris.org/os/licensing.
12 * See the License for the specific language governing
13 * permissions and limitations under the License.
14 *
15 * When distributing Covered Code, include this CDDL
16 * HEADER in each file and include the License file at
17 * usr/src/OPENSOLARIS.LICENSE.  If applicable,
18 * add the following below this CDDL HEADER, with the
19 * fields enclosed by brackets "[]" replaced with your
20 * own identifying information: Portions Copyright [yyyy]
21 * [name of copyright owner]
22 *
23 * CDDL HEADER END
24 */
25
26/*
27 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28 * Use is subject to license terms.
29 */
30
31/*
32 * The "cascade" test case is a multiprocess/multithread batten-passing model
33 * using lock primitives alone for synchronisation. Threads are arranged in a
34 * ring. Each thread has two locks of its own on which it blocks, and is able
35 * to manipulate the two locks belonging to the thread which follows it in the
36 * ring.
37 *
38 * The number of threads (nthreads) is specified by the generic libMicro -P/-T
39 * options. With nthreads == 1 (the default) the uncontended case can be timed.
40 *
41 * The main logic is generic and allows any simple blocking API to be tested.
42 * The API-specific component is clearly indicated.
43 */
44
45#include <unistd.h>
46#include <stdlib.h>
47#include <stdio.h>
48#include <fcntl.h>
49
50#include "libmicro.h"
51
52typedef struct {
53	int			ts_once;
54	int			ts_id;
55	int			ts_us0;		/* our lock indices */
56	int			ts_us1;
57	int			ts_them0;	/* their lock indices */
58	int			ts_them1;
59} tsd_t;
60
61static int			nthreads;
62
63/*
64 * API-specific code BEGINS here
65 */
66
67#define	DEFD			"/private/tmp"
68
69static char			*optd = DEFD;
70static int 			file;
71static int 			nlocks;
72
73int
74benchmark_init()
75{
76	lm_tsdsize = sizeof (tsd_t);
77
78	(void) sprintf(lm_optstr, "d:");
79
80	lm_defN = "cscd_fcntl";
81
82	(void) sprintf(lm_usage,
83	    "       [-d directory for temp file (default %s)]\n"
84	    "notes: thread cascade using fcntl region locking\n",
85	    DEFD);
86
87	return (0);
88}
89
90int
91benchmark_optswitch(int opt, char *optarg)
92{
93	switch (opt) {
94	case 'd':
95		optd = optarg;
96		break;
97	default:
98		return (-1);
99	}
100	return (0);
101}
102
103int
104benchmark_initrun()
105{
106	int			errors = 0;
107	char			fname[1024];
108
109	nthreads = lm_optP * lm_optT;
110	nlocks = nthreads * 2;
111
112	(void) sprintf(fname, "%s/cascade.%ld", optd, getpid());
113
114	file = open(fname, O_CREAT | O_TRUNC | O_RDWR, 0600);
115	if (file == -1) {
116		errors++;
117	}
118
119	if (unlink(fname)) {
120		errors++;
121	}
122
123	if (ftruncate(file, nlocks * 3) == -1) {
124		errors++;
125	}
126
127	return (errors);
128}
129
130int
131block(int index)
132{
133	struct flock		fl;
134
135	fl.l_type = F_WRLCK;
136	fl.l_whence = SEEK_SET;
137	fl.l_start = index;
138	fl.l_len = 1;
139	return (fcntl(file, F_SETLKW, &fl) == -1);
140}
141
142int
143unblock(int index)
144{
145	struct flock		fl;
146
147	fl.l_type = F_UNLCK;
148	fl.l_whence = SEEK_SET;
149	fl.l_start = index;
150	fl.l_len = 1;
151	return (fcntl(file, F_SETLK, &fl) == -1);
152}
153
154/*
155 * API-specific code ENDS here
156 */
157
158int
159benchmark_initbatch(void *tsd)
160{
161	tsd_t			*ts = (tsd_t *)tsd;
162	int			e = 0;
163
164	if (ts->ts_once == 0) {
165		int		us, them;
166
167#if !defined(__APPLE__)
168        us = (getpindex() * lm_optT) + gettindex();
169#else
170        us = gettsdindex(tsd);
171#endif /* __APPLE__ */
172
173		them = (us + 1) % (lm_optP * lm_optT);
174
175		ts->ts_id = us;
176
177		/* lock index asignment for us and them */
178		ts->ts_us0 = (us * 4);
179		ts->ts_us1 = (us * 4) + 2;
180		if (us < nthreads - 1) {
181			/* straight-thru connection to them */
182			ts->ts_them0 = (them * 4);
183			ts->ts_them1 = (them * 4) + 2;
184		} else {
185			/* cross-over connection to them */
186			ts->ts_them0 = (them * 4) + 2;
187			ts->ts_them1 = (them * 4);
188		}
189
190		ts->ts_once = 1;
191	}
192
193	/* block their first move */
194	e += block(ts->ts_them0);
195
196	return (e);
197}
198
199int
200benchmark(void *tsd, result_t *res)
201{
202	tsd_t			*ts = (tsd_t *)tsd;
203	int			i;
204	int			e = 0;
205
206	/* wait to be unblocked (id == 0 will not block) */
207	e += block(ts->ts_us0);
208
209	for (i = 0; i < lm_optB; i += 2) {
210		/* allow them to block us again */
211		e += unblock(ts->ts_us0);
212
213		/* block their next + 1 move */
214		e += block(ts->ts_them1);
215
216		/* unblock their next move */
217		e += unblock(ts->ts_them0);
218
219		/* wait for them to unblock us */
220		e += block(ts->ts_us1);
221
222		/* repeat with locks reversed */
223		e += unblock(ts->ts_us1);
224		e += block(ts->ts_them0);
225		e += unblock(ts->ts_them1);
226		e += block(ts->ts_us0);
227	}
228
229	/* finish batch with nothing blocked */
230	e += unblock(ts->ts_them0);
231	e += unblock(ts->ts_us0);
232
233	res->re_count = i;
234	res->re_errors = e;
235
236	return (0);
237}
238