]>
git.proxmox.com Git - mirror_qemu.git/blob - tests/atomic_add-bench.c
1 #include "qemu/osdep.h"
2 #include "qemu/thread.h"
3 #include "qemu/host-utils.h"
4 #include "qemu/processor.h"
15 static QemuThread
*threads
;
16 static struct thread_info
*th_info
;
17 static unsigned int n_threads
= 1;
18 static unsigned int n_ready_threads
;
19 static struct count
*counts
;
20 static unsigned int duration
= 1;
21 static unsigned int range
= 1024;
22 static bool use_mutex
;
23 static bool test_start
;
24 static bool test_stop
;
26 static const char commands_string
[] =
27 " -n = number of threads\n"
28 " -m = use mutexes instead of atomic increments\n"
29 " -p = enable sync profiler\n"
30 " -d = duration in seconds\n"
31 " -r = range (will be rounded up to pow2)";
33 static void usage_complete(char *argv
[])
35 fprintf(stderr
, "Usage: %s [options]\n", argv
[0]);
36 fprintf(stderr
, "options:\n%s\n", commands_string
);
40 * From: https://en.wikipedia.org/wiki/Xorshift
41 * This is faster than rand_r(), and gives us a wider range (RAND_MAX is only
42 * guaranteed to be >= INT_MAX).
44 static uint64_t xorshift64star(uint64_t x
)
49 return x
* UINT64_C(2685821657736338717);
52 static void *thread_func(void *arg
)
54 struct thread_info
*info
= arg
;
56 atomic_inc(&n_ready_threads
);
57 while (!atomic_read(&test_start
)) {
61 while (!atomic_read(&test_stop
)) {
64 info
->r
= xorshift64star(info
->r
);
65 index
= info
->r
& (range
- 1);
67 qemu_mutex_lock(&counts
[index
].lock
);
68 counts
[index
].val
+= 1;
69 qemu_mutex_unlock(&counts
[index
].lock
);
71 atomic_inc(&counts
[index
].val
);
77 static void run_test(void)
81 while (atomic_read(&n_ready_threads
) != n_threads
) {
85 atomic_set(&test_start
, true);
86 g_usleep(duration
* G_USEC_PER_SEC
);
87 atomic_set(&test_stop
, true);
89 for (i
= 0; i
< n_threads
; i
++) {
90 qemu_thread_join(&threads
[i
]);
94 static void create_threads(void)
98 threads
= g_new(QemuThread
, n_threads
);
99 th_info
= g_new(struct thread_info
, n_threads
);
100 counts
= qemu_memalign(64, sizeof(*counts
) * range
);
101 memset(counts
, 0, sizeof(*counts
) * range
);
102 for (i
= 0; i
< range
; i
++) {
103 qemu_mutex_init(&counts
[i
].lock
);
106 for (i
= 0; i
< n_threads
; i
++) {
107 struct thread_info
*info
= &th_info
[i
];
109 info
->r
= (i
+ 1) ^ time(NULL
);
110 qemu_thread_create(&threads
[i
], NULL
, thread_func
, info
,
111 QEMU_THREAD_JOINABLE
);
115 static void pr_params(void)
117 printf("Parameters:\n");
118 printf(" # of threads: %u\n", n_threads
);
119 printf(" duration: %u\n", duration
);
120 printf(" ops' range: %u\n", range
);
123 static void pr_stats(void)
125 unsigned long long val
= 0;
129 for (i
= 0; i
< range
; i
++) {
130 val
+= counts
[i
].val
;
132 tx
= val
/ duration
/ 1e6
;
134 printf("Results:\n");
135 printf("Duration: %u s\n", duration
);
136 printf(" Throughput: %.2f Mops/s\n", tx
);
137 printf(" Throughput/thread: %.2f Mops/s/thread\n", tx
/ n_threads
);
140 static void parse_args(int argc
, char *argv
[])
145 c
= getopt(argc
, argv
, "hd:n:mpr:");
151 usage_complete(argv
);
154 duration
= atoi(optarg
);
157 n_threads
= atoi(optarg
);
166 range
= pow2ceil(atoi(optarg
));
172 int main(int argc
, char *argv
[])
174 parse_args(argc
, argv
);