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我正在用 valgrind 测试一些软件。理想情况下，我希望一次打开 20 个或更多 valgrind 实例。但是，如果我并行运行超过 16 个实例，我会开始收到如下消息：

==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_269e37a6
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_d6b675e7
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_db46c594
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_51cd683d
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_86662832
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_226a8983
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_bb94a700
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_532d4b39
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_de4a957e
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_fcc23adf
==30533== VG_(mkstemp): failed to create temp file: /tmp/valgrind_proc_30533_cmdline_f41d332c
valgrind: Startup or configuration error:
valgrind:    Can't create client cmdline file in /pathtomyproject/
valgrind: Unable to start up properly.  Giving up.

一些进程（可能是其中的 1/3）反而因错误而终止

==30482== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)
==30482==
==30482== 1 errors in context 1 of 1:
==30482== Jump to the invalid address stated on the next line
==30482==    at 0x4C6: ???
==30482==    by 0x4005D2E: open_verify (dl-load.c:1914)
==30482==    by 0x4006362: open_path (dl-load.c:2175)
==30482==    by 0x4008799: _dl_map_object (dl-load.c:2407)
==30482==    by 0x400CFE1: openaux (dl-deps.c:65)
==30482==    by 0x400F175: _dl_catch_error (dl-error.c:178)
==30482==    by 0x400D6BD: _dl_map_object_deps (dl-deps.c:258)
==30482==    by 0x400350C: dl_main (rtld.c:1826)
==30482==    by 0x4015B23: _dl_sysdep_start (dl-sysdep.c:244)
==30482==    by 0x4005364: _dl_start (rtld.c:338)
==30482==    by 0x40016B7: ??? (in /lib/x86_64-linux-gnu/ld-2.15.so)
==30482==    by 0x4: ???
==30482==    by 0x7FF0007C6: ???
==30482==    by 0x7FF0007DD: ???
==30482==    by 0x7FF0007E2: ???
==30482==    by 0x7FF0007E9: ???
==30482==    by 0x7FF0007EE: ???
==30482==  Address 0x4c6 is not stack'd, malloc'd or (recently) free'd

运行这些调用时，不会在 /tmp 中创建任何文件，但我使用的用户帐户确实具有 /tmp 的读取、写入和执行权限。

我在网上找不到有关此错误的任何信息，但也许这里的某个地方对此有所了解？

编辑：一些进一步的实验表明，事实上，一次最多可以同时运行 5 个进程。

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1 回答 1

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错误来自这里：

// coregrind/m_libcfile.c

/* Create and open (-rw------) a tmp file name incorporating said arg.
   Returns -1 on failure, else the fd of the file.  If fullname is
   non-NULL, the file's name is written into it.  The number of bytes
   written is guaranteed not to exceed 64+strlen(part_of_name). */

Int VG_(mkstemp) ( HChar* part_of_name, /*OUT*/HChar* fullname )
{
   HChar  buf[200];
   Int    n, tries, fd;
   UInt   seed;
   SysRes sres;
   const HChar *tmpdir;

   vg_assert(part_of_name);
   n = VG_(strlen)(part_of_name);
   vg_assert(n > 0 && n < 100);

   seed = (VG_(getpid)() << 9) ^ VG_(getppid)();

   /* Determine sensible location for temporary files */
   tmpdir = VG_(tmpdir)();

   tries = 0;
   while (True) {
      if (tries++ > 10)
         return -1;
      VG_(sprintf)( buf, "%s/valgrind_%s_%08x",
                    tmpdir, part_of_name, VG_(random)( &seed ));
      if (0)
         VG_(printf)("VG_(mkstemp): trying: %s\n", buf);

      sres = VG_(open)(buf,
                       VKI_O_CREAT|VKI_O_RDWR|VKI_O_EXCL|VKI_O_TRUNC,
                       VKI_S_IRUSR|VKI_S_IWUSR);
      if (sr_isError(sres)) {
         VG_(umsg)("VG_(mkstemp): failed to create temp file: %s\n", buf);
         continue;
      }
      /* VG_(safe_fd) doesn't return if it fails. */
      fd = VG_(safe_fd)( sr_Res(sres) );
      if (fullname)
         VG_(strcpy)( fullname, buf );
      return fd;
   }
   /* NOTREACHED */
}

如您所见，如果有超过 10 个进程共享相同pid和ppid. 目前尚不清楚您是如何创建 20 个 valgrind 进程的——它们通常不应该共享pid。

您也许可以通过以下任一方式解决该问题

  • 创建您的 Valgrind 实例，使它们不共享相同的pid，或
  • TMPDIR为每个 Valgrind 实例设置不同的目录。
于 2012-12-23T01:51:09.350 回答