tests/probes/lttng-test.c

   1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
   2  *
   3  * lttng-test.c
   4  *
   5  * Linux Trace Toolkit Next Generation Test Module
   6  *
   7  * Copyright 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/proc_fs.h>
  13 #include <linux/byteorder/generic.h>
  14 #include <asm/byteorder.h>
  15
  16 #include <lttng-events.h>
  17 #include <lttng-tracer.h>
  18 #include <wrapper/tracepoint.h>
  19 #include <wrapper/kstrtox.h>
  20
  21 #define TP_MODULE_NOAUTOLOAD
  22 #define LTTNG_PACKAGE_BUILD
  23 #define CREATE_TRACE_POINTS
  24 #define TRACE_INCLUDE_PATH instrumentation/events/lttng-module
  25 #define TRACE_INCLUDE_FILE lttng-test
  26 #define LTTNG_INSTRUMENTATION
  27 #include <instrumentation/events/lttng-module/lttng-test.h>
  28
  29 DEFINE_TRACE(lttng_test_filter_event);
  30
  31 #define LTTNG_TEST_FILTER_EVENT_FILE    "lttng-test-filter-event"
  32
  33 #define LTTNG_WRITE_COUNT_MAX   64
  34
  35 static struct proc_dir_entry *lttng_test_filter_event_dentry;
  36
  37 static
  38 void trace_test_event(unsigned int nr_iter)
  39 {
  40         int i, netint;
  41         long values[] = { 1, 2, 3 };
  42         uint32_t net_values[] = { 1, 2, 3 };
  43         char text[10] = "test";
  44         char escape[10] = "\\*";
  45
  46         for (i = 0; i < 3; i++) {
  47                 net_values[i] = htonl(net_values[i]);
  48         }
  49         for (i = 0; i < nr_iter; i++) {
  50                 netint = htonl(i);
  51                 trace_lttng_test_filter_event(i, netint, values, text, strlen(text), escape, net_values);
  52         }
  53 }
  54
  55 /**
  56  * lttng_filter_event_write - trigger a lttng_test_filter_event
  57  * @file: file pointer
  58  * @user_buf: user string
  59  * @count: length to copy
  60  *
  61  * Return -1 on error, with EFAULT errno. Returns count on success.
  62  */
  63 static
  64 ssize_t lttng_test_filter_event_write(struct file *file, const char __user *user_buf,
  65                     size_t count, loff_t *ppos)
  66 {
  67         unsigned int nr_iter;
  68         ssize_t written;
  69         int ret;
  70
  71         /* Get the number of iterations */
  72         ret = lttng_kstrtouint_from_user(user_buf, count, 10, &nr_iter);
  73         if (ret) {
  74                 written = ret;
  75                 goto end;
  76         }
  77         /* Trace the event */
  78         trace_test_event(nr_iter);
  79         written = count;
  80         *ppos += written;
  81 end:
  82         return written;
  83 }
  84
  85 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
  86 static const struct proc_ops lttng_test_filter_event_proc_ops = {
  87         .proc_write = lttng_test_filter_event_write,
  88 };
  89 #else
  90 static const struct file_operations lttng_test_filter_event_proc_ops = {
  91         .write = lttng_test_filter_event_write,
  92 };
  93 #endif
  94
  95 static
  96 int __init lttng_test_init(void)
  97 {
  98         int ret = 0;
  99
 100         (void) wrapper_lttng_fixup_sig(THIS_MODULE);
 101         wrapper_vmalloc_sync_all();
 102         lttng_test_filter_event_dentry =
 103                         proc_create_data(LTTNG_TEST_FILTER_EVENT_FILE,
 104                                 S_IRUGO | S_IWUGO, NULL,
 105                                 &lttng_test_filter_event_proc_ops, NULL);
 106         if (!lttng_test_filter_event_dentry) {
 107                 printk(KERN_ERR "Error creating LTTng test filter file\n");
 108                 ret = -ENOMEM;
 109                 goto error;
 110         }
 111         ret = __lttng_events_init__lttng_test();
 112         if (ret)
 113                 goto error_events;
 114         return ret;
 115
 116 error_events:
 117         remove_proc_entry(LTTNG_TEST_FILTER_EVENT_FILE, NULL);
 118 error:
 119         return ret;
 120 }
 121
 122 module_init(lttng_test_init);
 123
 124 static
 125 void __exit lttng_test_exit(void)
 126 {
 127         __lttng_events_exit__lttng_test();
 128         if (lttng_test_filter_event_dentry)
 129                 remove_proc_entry(LTTNG_TEST_FILTER_EVENT_FILE, NULL);
 130 }
 131
 132 module_exit(lttng_test_exit);
 133
 134 MODULE_LICENSE("GPL and additional rights");
 135 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
 136 MODULE_DESCRIPTION("LTTng Test");
 137 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
 138         __stringify(LTTNG_MODULES_MINOR_VERSION) "."
 139         __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
 140         LTTNG_MODULES_EXTRAVERSION);