[OpenAFS-port-freebsd] Patch to set thread title for pthreaded viced

[Garrett Wollman]

Some operating systems (at least FreeBSD and OpenBSD) have the
pthread_set_name_np(3) interface to set the thread title.  Although
the manual page says:

     This is a debugging interface and using it on a day-by-day basis makes no
     sense.

...this is fact wrong: the thread title is pushed into the kernel,
where it can be observed by ps(1) and top(1), among others.  Here's a
patch that makes the threads started by viced itself set names for
themselves.  (Note that this has no effect on the threads that are
started through the Rx server API, but that's probably a good thing,
since the only thing it could say is "fileserver worker #42".)  There
are other operating systems that allow threads to set an
application-specific identifier (string or numeric) so perhaps this
function should actually be abstracted out into a common library.

I actually don't think that the current threading model used in the
fileserver actually makes much sense; I'll have more comments on that
when I've collected some actual data.

-GAWollman


---
 acinclude.m4      |    8 ++++++++
 src/viced/viced.c |    6 ++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/acinclude.m4 b/acinclude.m4
index 7452cbc..d4005de 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -1230,6 +1230,7 @@ AC_CHECK_HEADERS([ \
 		   ncurses.h \
 		   netdb.h \
 		   netinet/in.h \
+		   pthread_np.h \
 		   pwd.h \
 		   regex.h \
 		   resolv.h \
@@ -1499,6 +1500,13 @@ else
     AC_MSG_RESULT(no)
 fi
 
+if test "$ac_cv_header_pthread_np_h" = "yes"; then
+	openafs_old_LIBS="$LIBS"
+	LIBS="$LIBS $PTHREAD_LIBS"
+	AC_CHECK_FUNCS(pthread_set_name_np)
+	LIBS="$openafs_old_LIBS"
+fi
+
 AC_TYPE_SIGNAL
 OPENAFS_RETSIGTYPE
 AC_CHECK_SIZEOF(void *)
diff --git a/src/viced/viced.c b/src/viced/viced.c
index ce327e5..c5c3196 100644
--- a/src/viced/viced.c
+++ b/src/viced/viced.c
@@ -87,6 +87,9 @@
 #include "host.h"
 #ifdef AFS_PTHREAD_ENV
 #include <afs/softsig.h>
+#ifdef HAVE_PTHREAD_NP_H
+#include <pthread_np.h>
+#endif /* HAVE_PTHREAD_NP_H */
 #endif
 #if defined(AFS_SGI_ENV)
 #include "sys/schedctl.h"
@@ -431,6 +434,9 @@ setThreadId(char *s)
     /* set our 'thread-id' so that the host hold table works */
     pthread_setspecific(rx_thread_id_key,
 			(void *)(intptr_t)rx_NewThreadId());
+#ifdef HAVE_PTHREAD_SET_NAME_NP
+    pthread_set_name_np(pthread_self(), s);
+#endif
     ViceLog(0,
 	    ("Set thread id %p for '%s'\n",
 	     pthread_getspecific(rx_thread_id_key), s));
-- 
1.7.4.1