drivers/base/test/test_async_driver_probe.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2014 Google, Inc.
   4  */
   5
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8 #include <linux/delay.h>
   9 #include <linux/init.h>
  10 #include <linux/hrtimer.h>
  11 #include <linux/module.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/time.h>
  14 #include <linux/numa.h>
  15 #include <linux/nodemask.h>
  16 #include <linux/topology.h>
  17
  18 #define TEST_PROBE_DELAY        (5 * 1000)      /* 5 sec */
  19 #define TEST_PROBE_THRESHOLD    (TEST_PROBE_DELAY / 2)
  20
  21 static atomic_t warnings, errors, timeout, async_completed;
  22
  23 static int test_probe(struct platform_device *pdev)
  24 {
  25         struct device *dev = &pdev->dev;
  26
  27         /*
  28          * Determine if we have hit the "timeout" limit for the test if we
  29          * have then report it as an error, otherwise we wil sleep for the
  30          * required amount of time and then report completion.
  31          */
  32         if (atomic_read(&timeout)) {
  33                 dev_err(dev, "async probe took too long\n");
  34                 atomic_inc(&errors);
  35         } else {
  36                 dev_dbg(&pdev->dev, "sleeping for %d msecs in probe\n",
  37                          TEST_PROBE_DELAY);
  38                 msleep(TEST_PROBE_DELAY);
  39                 dev_dbg(&pdev->dev, "done sleeping\n");
  40         }
  41
  42         /*
  43          * Report NUMA mismatch if device node is set and we are not
  44          * performing an async init on that node.
  45          */
  46         if (dev->driver->probe_type == PROBE_PREFER_ASYNCHRONOUS) {
  47                 if (IS_ENABLED(CONFIG_NUMA) &&
  48                     dev_to_node(dev) != numa_node_id()) {
  49                         dev_warn(dev, "NUMA node mismatch %d != %d\n",
  50                                  dev_to_node(dev), numa_node_id());
  51                         atomic_inc(&warnings);
  52                 }
  53
  54                 atomic_inc(&async_completed);
  55         }
  56
  57         return 0;
  58 }
  59
  60 static struct platform_driver async_driver = {
  61         .driver = {
  62                 .name = "test_async_driver",
  63                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
  64         },
  65         .probe = test_probe,
  66 };
  67
  68 static struct platform_driver sync_driver = {
  69         .driver = {
  70                 .name = "test_sync_driver",
  71                 .probe_type = PROBE_FORCE_SYNCHRONOUS,
  72         },
  73         .probe = test_probe,
  74 };
  75
  76 static struct platform_device *async_dev[NR_CPUS * 2];
  77 static struct platform_device *sync_dev[2];
  78
  79 static struct platform_device *
  80 test_platform_device_register_node(char *name, int id, int nid)
  81 {
  82         struct platform_device *pdev;
  83         int ret;
  84
  85         pdev = platform_device_alloc(name, id);
  86         if (!pdev)
  87                 return NULL;
  88
  89         if (nid != NUMA_NO_NODE)
  90                 set_dev_node(&pdev->dev, nid);
  91
  92         ret = platform_device_add(pdev);
  93         if (ret) {
  94                 platform_device_put(pdev);
  95                 return ERR_PTR(ret);
  96         }
  97
  98         return pdev;
  99
 100 }
 101
 102 static int __init test_async_probe_init(void)
 103 {
 104         struct platform_device **pdev = NULL;
 105         int async_id = 0, sync_id = 0;
 106         unsigned long long duration;
 107         ktime_t calltime, delta;
 108         int err, nid, cpu;
 109
 110         pr_info("registering first set of asynchronous devices...\n");
 111
 112         for_each_online_cpu(cpu) {
 113                 nid = cpu_to_node(cpu);
 114                 pdev = &async_dev[async_id];
 115                 *pdev = test_platform_device_register_node("test_async_driver",
 116                                                            async_id,
 117                                                            nid);
 118                 if (IS_ERR(*pdev)) {
 119                         err = PTR_ERR(*pdev);
 120                         *pdev = NULL;
 121                         pr_err("failed to create async_dev: %d\n", err);
 122                         goto err_unregister_async_devs;
 123                 }
 124
 125                 async_id++;
 126         }
 127
 128         pr_info("registering asynchronous driver...\n");
 129         calltime = ktime_get();
 130         err = platform_driver_register(&async_driver);
 131         if (err) {
 132                 pr_err("Failed to register async_driver: %d\n", err);
 133                 goto err_unregister_async_devs;
 134         }
 135
 136         delta = ktime_sub(ktime_get(), calltime);
 137         duration = (unsigned long long) ktime_to_ms(delta);
 138         pr_info("registration took %lld msecs\n", duration);
 139         if (duration > TEST_PROBE_THRESHOLD) {
 140                 pr_err("test failed: probe took too long\n");
 141                 err = -ETIMEDOUT;
 142                 goto err_unregister_async_driver;
 143         }
 144
 145         pr_info("registering second set of asynchronous devices...\n");
 146         calltime = ktime_get();
 147         for_each_online_cpu(cpu) {
 148                 nid = cpu_to_node(cpu);
 149                 pdev = &sync_dev[sync_id];
 150
 151                 *pdev = test_platform_device_register_node("test_async_driver",
 152                                                            async_id,
 153                                                            nid);
 154                 if (IS_ERR(*pdev)) {
 155                         err = PTR_ERR(*pdev);
 156                         *pdev = NULL;
 157                         pr_err("failed to create async_dev: %d\n", err);
 158                         goto err_unregister_async_driver;
 159                 }
 160
 161                 async_id++;
 162         }
 163
 164         delta = ktime_sub(ktime_get(), calltime);
 165         duration = (unsigned long long) ktime_to_ms(delta);
 166         dev_info(&(*pdev)->dev,
 167                  "registration took %lld msecs\n", duration);
 168         if (duration > TEST_PROBE_THRESHOLD) {
 169                 dev_err(&(*pdev)->dev,
 170                         "test failed: probe took too long\n");
 171                 err = -ETIMEDOUT;
 172                 goto err_unregister_async_driver;
 173         }
 174
 175
 176         pr_info("registering first synchronous device...\n");
 177         nid = cpu_to_node(cpu);
 178         pdev = &sync_dev[sync_id];
 179
 180         *pdev = test_platform_device_register_node("test_sync_driver",
 181                                                    sync_id,
 182                                                    NUMA_NO_NODE);
 183         if (IS_ERR(*pdev)) {
 184                 err = PTR_ERR(*pdev);
 185                 *pdev = NULL;
 186                 pr_err("failed to create sync_dev: %d\n", err);
 187                 goto err_unregister_async_driver;
 188         }
 189
 190         sync_id++;
 191
 192         pr_info("registering synchronous driver...\n");
 193         calltime = ktime_get();
 194         err = platform_driver_register(&sync_driver);
 195         if (err) {
 196                 pr_err("Failed to register async_driver: %d\n", err);
 197                 goto err_unregister_sync_devs;
 198         }
 199
 200         delta = ktime_sub(ktime_get(), calltime);
 201         duration = (unsigned long long) ktime_to_ms(delta);
 202         pr_info("registration took %lld msecs\n", duration);
 203         if (duration < TEST_PROBE_THRESHOLD) {
 204                 dev_err(&(*pdev)->dev,
 205                         "test failed: probe was too quick\n");
 206                 err = -ETIMEDOUT;
 207                 goto err_unregister_sync_driver;
 208         }
 209
 210         pr_info("registering second synchronous device...\n");
 211         pdev = &sync_dev[sync_id];
 212         calltime = ktime_get();
 213
 214         *pdev = test_platform_device_register_node("test_sync_driver",
 215                                                    sync_id,
 216                                                    NUMA_NO_NODE);
 217         if (IS_ERR(*pdev)) {
 218                 err = PTR_ERR(*pdev);
 219                 *pdev = NULL;
 220                 pr_err("failed to create sync_dev: %d\n", err);
 221                 goto err_unregister_sync_driver;
 222         }
 223
 224         sync_id++;
 225
 226         delta = ktime_sub(ktime_get(), calltime);
 227         duration = (unsigned long long) ktime_to_ms(delta);
 228         dev_info(&(*pdev)->dev,
 229                  "registration took %lld msecs\n", duration);
 230         if (duration < TEST_PROBE_THRESHOLD) {
 231                 dev_err(&(*pdev)->dev,
 232                         "test failed: probe was too quick\n");
 233                 err = -ETIMEDOUT;
 234                 goto err_unregister_sync_driver;
 235         }
 236
 237         /*
 238          * The async events should have completed while we were taking care
 239          * of the synchronous events. We will now terminate any outstanding
 240          * asynchronous probe calls remaining by forcing timeout and remove
 241          * the driver before we return which should force the flush of the
 242          * pending asynchronous probe calls.
 243          *
 244          * Otherwise if they completed without errors or warnings then
 245          * report successful completion.
 246          */
 247         if (atomic_read(&async_completed) != async_id) {
 248                 pr_err("async events still pending, forcing timeout\n");
 249                 atomic_inc(&timeout);
 250                 err = -ETIMEDOUT;
 251         } else if (!atomic_read(&errors) && !atomic_read(&warnings)) {
 252                 pr_info("completed successfully\n");
 253                 return 0;
 254         }
 255
 256 err_unregister_sync_driver:
 257         platform_driver_unregister(&sync_driver);
 258 err_unregister_sync_devs:
 259         while (sync_id--)
 260                 platform_device_unregister(sync_dev[sync_id]);
 261 err_unregister_async_driver:
 262         platform_driver_unregister(&async_driver);
 263 err_unregister_async_devs:
 264         while (async_id--)
 265                 platform_device_unregister(async_dev[async_id]);
 266
 267         /*
 268          * If err is already set then count that as an additional error for
 269          * the test. Otherwise we will report an invalid argument error and
 270          * not count that as we should have reached here as a result of
 271          * errors or warnings being reported by the probe routine.
 272          */
 273         if (err)
 274                 atomic_inc(&errors);
 275         else
 276                 err = -EINVAL;
 277
 278         pr_err("Test failed with %d errors and %d warnings\n",
 279                atomic_read(&errors), atomic_read(&warnings));
 280
 281         return err;
 282 }
 283 module_init(test_async_probe_init);
 284
 285 static void __exit test_async_probe_exit(void)
 286 {
 287         int id = 2;
 288
 289         platform_driver_unregister(&async_driver);
 290         platform_driver_unregister(&sync_driver);
 291
 292         while (id--)
 293                 platform_device_unregister(sync_dev[id]);
 294
 295         id = NR_CPUS * 2;
 296         while (id--)
 297                 platform_device_unregister(async_dev[id]);
 298 }
 299 module_exit(test_async_probe_exit);
 300
 301 MODULE_DESCRIPTION("Test module for asynchronous driver probing");
 302 MODULE_AUTHOR("Dmitry Torokhov <dtor@chromium.org>");
 303 MODULE_LICENSE("GPL");