File bandaid-dtv-surplus.diff of Package glibc.6400

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File bandaid-dtv-surplus.diff of Package glibc.6400

A bandaid for bnc#919678 (DTV_SURPLUS running out in some scenarios).
This bandaid comes from Fedora
 ( https://sourceware.org/ml/libc-alpha/2014-10/msg00134.html ).
The real solution
 ( https://sourceware.org/ml/libc-alpha/2014-11/msg00590.html )
was a bit too late to comfortably be included in SLE11 SP4 (and SP3).

Index: glibc-2.19/sysdeps/generic/ldsodefs.h
===================================================================
--- glibc-2.19.orig/sysdeps/generic/ldsodefs.h
+++ glibc-2.19/sysdeps/generic/ldsodefs.h
@@ -391,8 +391,18 @@ struct rtld_global
    have to iterate beyond the first element in the slotinfo list.  */
 #define TLS_SLOTINFO_SURPLUS (62)
 
-/* Number of additional slots in the dtv allocated.  */
-#define DTV_SURPLUS	(14)
+/* Number of additional allocated dtv slots.  This was initially
+   14, but problems with python, MESA, and X11's uses of static TLS meant
+   that most distributions were very close to this limit when they loaded
+   dynamically interpreted languages that used graphics. The simplest
+   solution was to roughly double the number of slots. The actual static
+   image space usage was relatively small, for example in MESA you
+   had only two dispatch pointers for a total of 16 bytes.  If we hit up
+   against this limit again we should start a campaign with the
+   distributions to coordinate the usage of static TLS.  Any user of this
+   resource is effectively coordinating a global resource since this
+   surplus is allocated for each thread at startup.  */
+#define DTV_SURPLUS    (32)
 
   /* Initial dtv of the main thread, not allocated with normal malloc.  */
   EXTERN void *_dl_initial_dtv;

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File bandaid-dtv-surplus.diff of Package glibc.6400

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