Re: [PATCH] Add test for pthread_setname_np and pthread_getname_np.

["Carlos O'Donell" <carlos at redhat dot com>]

On 02/05/2014 10:00 AM, Joseph S. Myers wrote:
> On Tue, 4 Feb 2014, Carlos O'Donell wrote:
> 
>> diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
>> index 3723535..d59531c 100644
>> --- a/sysdeps/unix/sysv/linux/kernel-features.h
>> +++ b/sysdeps/unix/sysv/linux/kernel-features.h
>> @@ -199,7 +199,10 @@
>>  
>>  /* Support for the recvmmsg syscall was added in 2.6.33.  */
>>  #if __LINUX_KERNEL_VERSION >= 0x020621
>> -# define __ASSUME_RECVMMSG     1
>> +# define __ASSUME_RECVMMSG             1
>> +/* Assume that /proc/self/task/$tid/comm and /proc/$pid/task/$tid/comm
>> +   exist.  */
>> +# define __ASSUME_PROC_PID_TASK_COMM   1
>>  #endif
> 
> This does not belong under the recvmmsg conditional; they should have 
> separate #if conditionals, each with its own comment.
> 
> (It seems quite likely recvmmsg could have the same issue as accept4, with 
> that macro needing splitting into three, as discussed for accept4 in 
> <https://sourceware.org/ml/libc-alpha/2013-12/msg00014.html>; all of 
> accept4, recvmmsg and sendmmsg follow the same pattern of, depending on 
> the architecture, possibly being implemented through socketcall, a more 
> specific syscall or both, with the potential for a syscall being added 
> later than the socketcall support.  After moving the minimum to 2.6.32 I'm 
> thinking of reviewing the remaining __ASSUME_* macros properly.)

Thanks, I've checked this in.

/
2014-02-05  Carlos O'Donell  <carlos@rehdat.com>

       * sysdeps/unix/sysv/linux/kernel-features.h
       [__LINUX_KERNEL_VERSION >= 0x020621]
       (__ASSUME_PROC_PID_TASK_COMM): Define.

nptl/
2014-02-05  Carlos O'Donell  <carlos@redhat.com>
       * sysdeps/unix/sysv/linux/tst-setgetname.c (do_test): Skip the
       test if !__ASSUME_PROC_PID_TASK_COMM and get_self_comm returns
       ENOENT.

 diff --git a/nptl/sysdeps/unix/sysv/linux/tst-setgetname.c b/nptl/sysdeps/unix/sysv/linux/tst-setgetname.c
index 2aceba5..f5693e2 100644
--- a/nptl/sysdeps/unix/sysv/linux/tst-setgetname.c
+++ b/nptl/sysdeps/unix/sysv/linux/tst-setgetname.c
@@ -23,6 +23,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <kernel-features.h>
 
 /* New name of process.  */
 #define NEW_NAME "setname"
@@ -99,6 +100,19 @@ do_test (int argc, char **argv)
   if (res == 0)
     {
       res = get_self_comm (gettid (), name_check, TASK_COMM_LEN);
+
+#if !__ASSUME_PROC_PID_TASK_COMM
+      /* On this first test we look for ENOENT to be returned from
+         get_self_comm to indicate that the kernel is older than
+         2.6.33 and doesn't contain comm within the proc structure.
+         In that case we skip the entire test.  */
+      if (res == ENOENT)
+       {
+         printf ("SKIP: The kernel does not have /proc/self/task/%%lu/comm.\n");
+         return 0;
+       }
+#endif
+
       if (res == 0)
        {
          if (strncmp (name, name_check, strlen (BIG_NAME)) == 0)
diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
index 3723535..aabf69d 100644
--- a/sysdeps/unix/sysv/linux/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -202,6 +202,12 @@
 # define __ASSUME_RECVMMSG     1
 #endif
 
+/* Support for /proc/self/task/$tid/comm and /proc/$pid/task/$tid/comm were
+   added in 2.6.33.  */
+#if __LINUX_KERNEL_VERSION >= 0x020621
+# define __ASSUME_PROC_PID_TASK_COMM   1
+#endif
+
 /* statfs fills in f_flags since 2.6.36.  */
 #if __LINUX_KERNEL_VERSION >= 0x020624
 # define __ASSUME_STATFS_F_FLAGS       1
---

Cheers,
Carlos.