jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
1#include "qemu/osdep.h"
2#include "qemu-common.h"
3#include "block/aio.h"
4#include "block/thread-pool.h"
5#include "block/block.h"
6#include "qapi/error.h"
7#include "qemu/timer.h"
8#include "qemu/error-report.h"
9#include "qemu/main-loop.h"
10
11static AioContext *ctx;
12static ThreadPool *pool;
13static int active;
14
15typedef struct {
16 BlockAIOCB *aiocb;
17 int n;
18 int ret;
19} WorkerTestData;
20
21static int worker_cb(void *opaque)
22{
23 WorkerTestData *data = opaque;
24 return atomic_fetch_inc(&data->n);
25}
26
27static int long_cb(void *opaque)
28{
29 WorkerTestData *data = opaque;
30 atomic_inc(&data->n);
31 g_usleep(2000000);
32 atomic_inc(&data->n);
33 return 0;
34}
35
36static void done_cb(void *opaque, int ret)
37{
38 WorkerTestData *data = opaque;
39 g_assert(data->ret == -EINPROGRESS || data->ret == -ECANCELED);
40 data->ret = ret;
41 data->aiocb = NULL;
42
43 /* Callbacks are serialized, so no need to use atomic ops. */
44 active--;
45}
46
47static void test_submit(void)
48{
49 WorkerTestData data = { .n = 0 };
50 thread_pool_submit(pool, worker_cb, &data);
51 while (data.n == 0) {
52 aio_poll(ctx, true);
53 }
54 g_assert_cmpint(data.n, ==, 1);
55}
56
57static void test_submit_aio(void)
58{
59 WorkerTestData data = { .n = 0, .ret = -EINPROGRESS };
60 data.aiocb = thread_pool_submit_aio(pool, worker_cb, &data,
61 done_cb, &data);
62
63 /* The callbacks are not called until after the first wait. */
64 active = 1;
65 g_assert_cmpint(data.ret, ==, -EINPROGRESS);
66 while (data.ret == -EINPROGRESS) {
67 aio_poll(ctx, true);
68 }
69 g_assert_cmpint(active, ==, 0);
70 g_assert_cmpint(data.n, ==, 1);
71 g_assert_cmpint(data.ret, ==, 0);
72}
73
74static void co_test_cb(void *opaque)
75{
76 WorkerTestData *data = opaque;
77
78 active = 1;
79 data->n = 0;
80 data->ret = -EINPROGRESS;
81 thread_pool_submit_co(pool, worker_cb, data);
82
83 /* The test continues in test_submit_co, after qemu_coroutine_enter... */
84
85 g_assert_cmpint(data->n, ==, 1);
86 data->ret = 0;
87 active--;
88
89 /* The test continues in test_submit_co, after aio_poll... */
90}
91
92static void test_submit_co(void)
93{
94 WorkerTestData data;
95 Coroutine *co = qemu_coroutine_create(co_test_cb, &data);
96
97 qemu_coroutine_enter(co);
98
99 /* Back here once the worker has started. */
100
101 g_assert_cmpint(active, ==, 1);
102 g_assert_cmpint(data.ret, ==, -EINPROGRESS);
103
104 /* aio_poll will execute the rest of the coroutine. */
105
106 while (data.ret == -EINPROGRESS) {
107 aio_poll(ctx, true);
108 }
109
110 /* Back here after the coroutine has finished. */
111
112 g_assert_cmpint(active, ==, 0);
113 g_assert_cmpint(data.ret, ==, 0);
114}
115
116static void test_submit_many(void)
117{
118 WorkerTestData data[100];
119 int i;
120
121 /* Start more work items than there will be threads. */
122 for (i = 0; i < 100; i++) {
123 data[i].n = 0;
124 data[i].ret = -EINPROGRESS;
125 thread_pool_submit_aio(pool, worker_cb, &data[i], done_cb, &data[i]);
126 }
127
128 active = 100;
129 while (active > 0) {
130 aio_poll(ctx, true);
131 }
132 for (i = 0; i < 100; i++) {
133 g_assert_cmpint(data[i].n, ==, 1);
134 g_assert_cmpint(data[i].ret, ==, 0);
135 }
136}
137
138static void do_test_cancel(bool sync)
139{
140 WorkerTestData data[100];
141 int num_canceled;
142 int i;
143
144 /* Start more work items than there will be threads, to ensure
145 * the pool is full.
146 */
147 test_submit_many();
148
149 /* Start long running jobs, to ensure we can cancel some. */
150 for (i = 0; i < 100; i++) {
151 data[i].n = 0;
152 data[i].ret = -EINPROGRESS;
153 data[i].aiocb = thread_pool_submit_aio(pool, long_cb, &data[i],
154 done_cb, &data[i]);
155 }
156
157 /* Starting the threads may be left to a bottom half. Let it
158 * run, but do not waste too much time...
159 */
160 active = 100;
161 aio_notify(ctx);
162 aio_poll(ctx, false);
163
164 /* Wait some time for the threads to start, with some sanity
165 * testing on the behavior of the scheduler...
166 */
167 g_assert_cmpint(active, ==, 100);
168 g_usleep(1000000);
169 g_assert_cmpint(active, >, 50);
170
171 /* Cancel the jobs that haven't been started yet. */
172 num_canceled = 0;
173 for (i = 0; i < 100; i++) {
174 if (atomic_cmpxchg(&data[i].n, 0, 3) == 0) {
175 data[i].ret = -ECANCELED;
176 if (sync) {
177 bdrv_aio_cancel(data[i].aiocb);
178 } else {
179 bdrv_aio_cancel_async(data[i].aiocb);
180 }
181 num_canceled++;
182 }
183 }
184 g_assert_cmpint(active, >, 0);
185 g_assert_cmpint(num_canceled, <, 100);
186
187 for (i = 0; i < 100; i++) {
188 if (data[i].aiocb && data[i].n != 3) {
189 if (sync) {
190 /* Canceling the others will be a blocking operation. */
191 bdrv_aio_cancel(data[i].aiocb);
192 } else {
193 bdrv_aio_cancel_async(data[i].aiocb);
194 }
195 }
196 }
197
198 /* Finish execution and execute any remaining callbacks. */
199 while (active > 0) {
200 aio_poll(ctx, true);
201 }
202 g_assert_cmpint(active, ==, 0);
203 for (i = 0; i < 100; i++) {
204 if (data[i].n == 3) {
205 g_assert_cmpint(data[i].ret, ==, -ECANCELED);
206 g_assert(data[i].aiocb == NULL);
207 } else {
208 g_assert_cmpint(data[i].n, ==, 2);
209 g_assert(data[i].ret == 0 || data[i].ret == -ECANCELED);
210 g_assert(data[i].aiocb == NULL);
211 }
212 }
213}
214
215static void test_cancel(void)
216{
217 do_test_cancel(true);
218}
219
220static void test_cancel_async(void)
221{
222 do_test_cancel(false);
223}
224
225int main(int argc, char **argv)
226{
227 int ret;
228
229 qemu_init_main_loop(&error_abort);
230 ctx = qemu_get_current_aio_context();
231 pool = aio_get_thread_pool(ctx);
232
233 g_test_init(&argc, &argv, NULL);
234 g_test_add_func("/thread-pool/submit", test_submit);
235 g_test_add_func("/thread-pool/submit-aio", test_submit_aio);
236 g_test_add_func("/thread-pool/submit-co", test_submit_co);
237 g_test_add_func("/thread-pool/submit-many", test_submit_many);
238 g_test_add_func("/thread-pool/cancel", test_cancel);
239 g_test_add_func("/thread-pool/cancel-async", test_cancel_async);
240
241 ret = g_test_run();
242
243 return ret;
244}