Update.

	    Jakub Jelinek  <jakub@redhat.com>

	* nscd/Makefile (nscd-modules): Add nscd_setup_thread.
	* nscd/connections.c (nscd_run): Call setup_thread for maintenance
	threads.
	* nscd/nscd-client.h (struct database_pers_head): Add
	nscd_certainly_running field.
	* nscd/nscd.h: Declare setup_thread.
	* nscd/nscd_helper.c (__nscd_get_map_ref): Avoid the time test if
	nscd_certainly_running is nonzero.

2004-09-08  Ulrich Drepper  <drepper@redhat.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/nscd_setup_thread.c b/sysdeps/unix/sysv/linux/nscd_setup_thread.c
new file mode 100644
index 0000000000..3496f02dca
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/nscd_setup_thread.c
@@ -0,0 +1,47 @@
+/* Setup of nscd worker threads.  Linux verison.
+   Copyright (C) 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <string.h>
+#include <unistd.h>
+#include <nscd.h>
+#include <sysdep.h>
+
+
+void
+setup_thread (struct database_dyn *db)
+{
+  /* Only supported when NPTL is used.  */
+  char buf[100];
+  if (confstr (_CS_GNU_LIBPTHREAD_VERSION, buf, sizeof (buf)) >= sizeof (buf)
+      || strncmp (buf, "NPTL", 4) != 0)
+    return;
+
+  /* Do not try this at home, kids.  We play with the SETTID address
+     even thought the process is multi-threaded.  This can only work
+     since none of the threads ever terminates.  */
+  INTERNAL_SYSCALL_DECL (err);
+  int r = INTERNAL_SYSCALL (set_tid_address, err, 1,
+			    &db->head->nscd_certainly_running);
+  if (!INTERNAL_SYSCALL_ERROR_P (r, err))
+    /* We know the kernel can reset this field when nscd terminates.
+       So, set the field to a nonzero value which indicates that nscd
+       is certainly running and clients can skip the test.  */
+    db->head->nscd_certainly_running = 1;
+}