Re: [PATCH 1/5][v2][BZ #15022] Avoid repeated calls to DL_STATIC_INIT

["Maciej W. Rozycki" <macro@codesourcery.com>]

On Fri, 21 Jun 2013, Roland McGrath wrote:

> I concur with your analysis.  (I was considering the relationship of the
> two locks when responding to HJ earlier, but failed to be clear about it.)
> I think it's wise to make the removal of the extraneous lock a separate
> follow-up change, just for paranoia's sake (i.e. ease of reversion if
> needed for some unforeseen reason).

 Thanks for confirming.  I have applied this change now, and the change 
below to remove the lock (no regressions in testing).

> The issue of the internal lock held while calling user initializers is
> entirely separate.  It has concerned me before when I've noticed it in
> passing, but I never dawdled long enough to bring it up for discussion.  I
> think you should file a bug about that one and we'll consider it separately
> later.  But that will clearly have to be after the impending freeze.

 BZ #15686 now.

2013-06-27  Maciej W. Rozycki  <macro@codesourcery.com>

	ports/ChangeLog.ia64
	* sysdeps/unix/sysv/linux/ia64/dl-static.c: Do not include
	<bits/libc-lock.h>.
	(_dl_static_lock): Remove variable.
	(_dl_static_init): Remove _dl_static_lock locking.

	ports/ChangeLog.mips
	* sysdeps/unix/sysv/linux/mips/dl-static.c: Do not include
	<bits/libc-lock.h>.
	(_dl_static_lock): Remove variable.
	(_dl_static_init): Remove _dl_static_lock locking.

  Maciej

glibc-static-dl-init-lock.diff
Index: glibc-fsf-trunk-quilt/ports/sysdeps/unix/sysv/linux/ia64/dl-static.c
===================================================================
--- glibc-fsf-trunk-quilt.orig/ports/sysdeps/unix/sysv/linux/ia64/dl-static.c	2013-06-18 01:05:31.000000000 +0100
+++ glibc-fsf-trunk-quilt/ports/sysdeps/unix/sysv/linux/ia64/dl-static.c	2013-06-21 19:54:31.852772816 +0100
@@ -35,9 +35,6 @@ _dl_var_init (void *array[])
 }
 
 #else
-#include <bits/libc-lock.h>
-
-__libc_lock_define_initialized_recursive (static, _dl_static_lock)
 
 static void *variables[] =
 {
@@ -52,8 +49,6 @@ _dl_static_init (struct link_map *map)
   lookup_t loadbase;
   void (*f) (void *[]);
 
-  __libc_lock_lock_recursive (_dl_static_lock);
-
   loadbase = _dl_lookup_symbol_x ("_dl_var_init", map, &ref,
 				  map->l_local_scope, NULL, 0, 1, NULL);
   if (ref != NULL)
@@ -61,8 +56,6 @@ _dl_static_init (struct link_map *map)
       f = (void (*) (void *[])) DL_SYMBOL_ADDRESS (loadbase, ref);
       f (variables);
     }
-
-  __libc_lock_unlock_recursive (_dl_static_lock);
 }
 
 #endif
Index: glibc-fsf-trunk-quilt/ports/sysdeps/unix/sysv/linux/mips/dl-static.c
===================================================================
--- glibc-fsf-trunk-quilt.orig/ports/sysdeps/unix/sysv/linux/mips/dl-static.c	2013-06-18 01:05:31.000000000 +0100
+++ glibc-fsf-trunk-quilt/ports/sysdeps/unix/sysv/linux/mips/dl-static.c	2013-06-21 19:54:51.852817334 +0100
@@ -33,9 +33,6 @@ _dl_var_init (void *array[])
 }
 
 #else
-#include <bits/libc-lock.h>
-
-__libc_lock_define_initialized_recursive (static, _dl_static_lock)
 
 static void *variables[] =
 {
@@ -64,8 +61,6 @@ _dl_static_init (struct link_map *l)
   void (*f) (void *[]);
   size_t i;
 
-  __libc_lock_lock_recursive (_dl_static_lock);
-
   loadbase = _dl_lookup_symbol_x ("_dl_var_init", l, &ref, l->l_local_scope,
 				  NULL, 0, 1, NULL);
 
@@ -84,8 +79,6 @@ _dl_static_init (struct link_map *l)
       f (variables);
       _dl_protect_relro (rtld_map);
     }
-
-  __libc_lock_unlock_recursive (_dl_static_lock);
 }
 
 #endif