tools/testing/selftests/bpf/prog_tests/trace_vprintk.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2021 Facebook */
   3
   4 #include <test_progs.h>
   5
   6 #include "trace_vprintk.lskel.h"
   7
   8 #define TRACEBUF        "/sys/kernel/debug/tracing/trace_pipe"
   9 #define SEARCHMSG       "1,2,3,4,5,6,7,8,9,10"
  10
  11 void serial_test_trace_vprintk(void)
  12 {
  13         struct trace_vprintk_lskel__bss *bss;
  14         int err = 0, iter = 0, found = 0;
  15         struct trace_vprintk_lskel *skel;
  16         char *buf = NULL;
  17         FILE *fp = NULL;
  18         size_t buflen;
  19
  20         skel = trace_vprintk_lskel__open_and_load();
  21         if (!ASSERT_OK_PTR(skel, "trace_vprintk__open_and_load"))
  22                 goto cleanup;
  23
  24         bss = skel->bss;
  25
  26         err = trace_vprintk_lskel__attach(skel);
  27         if (!ASSERT_OK(err, "trace_vprintk__attach"))
  28                 goto cleanup;
  29
  30         fp = fopen(TRACEBUF, "r");
  31         if (!ASSERT_OK_PTR(fp, "fopen(TRACEBUF)"))
  32                 goto cleanup;
  33
  34         /* We do not want to wait forever if this test fails... */
  35         fcntl(fileno(fp), F_SETFL, O_NONBLOCK);
  36
  37         /* wait for tracepoint to trigger */
  38         usleep(1);
  39         trace_vprintk_lskel__detach(skel);
  40
  41         if (!ASSERT_GT(bss->trace_vprintk_ran, 0, "bss->trace_vprintk_ran"))
  42                 goto cleanup;
  43
  44         if (!ASSERT_GT(bss->trace_vprintk_ret, 0, "bss->trace_vprintk_ret"))
  45                 goto cleanup;
  46
  47         /* verify our search string is in the trace buffer */
  48         while (getline(&buf, &buflen, fp) >= 0 || errno == EAGAIN) {
  49                 if (strstr(buf, SEARCHMSG) != NULL)
  50                         found++;
  51                 if (found == bss->trace_vprintk_ran)
  52                         break;
  53                 if (++iter > 1000)
  54                         break;
  55         }
  56
  57         if (!ASSERT_EQ(found, bss->trace_vprintk_ran, "found"))
  58                 goto cleanup;
  59
  60         if (!ASSERT_LT(bss->null_data_vprintk_ret, 0, "bss->null_data_vprintk_ret"))
  61                 goto cleanup;
  62
  63 cleanup:
  64         trace_vprintk_lskel__destroy(skel);
  65         free(buf);
  66         if (fp)
  67                 fclose(fp);
  68 }