diff options
Diffstat (limited to 'rtld-Avoid-using-up-static-TLS-surplus-for-optimizat.patch')
| -rw-r--r-- | rtld-Avoid-using-up-static-TLS-surplus-for-optimizat.patch | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/rtld-Avoid-using-up-static-TLS-surplus-for-optimizat.patch b/rtld-Avoid-using-up-static-TLS-surplus-for-optimizat.patch new file mode 100644 index 0000000..d70be0b --- /dev/null +++ b/rtld-Avoid-using-up-static-TLS-surplus-for-optimizat.patch @@ -0,0 +1,586 @@ +From ffb17e7ba3a5ba9632cee97330b325072fbe41dd Mon Sep 17 00:00:00 2001 +From: Szabolcs Nagy <szabolcs.nagy@arm.com> +Date: Wed, 10 Jun 2020 13:40:40 +0100 +Subject: [PATCH] rtld: Avoid using up static TLS surplus for optimizations [BZ + #25051] + +On some targets static TLS surplus area can be used opportunistically +for dynamically loaded modules such that the TLS access then becomes +faster (TLSDESC and powerpc TLS optimization). However we don't want +all surplus TLS to be used for this optimization because dynamically +loaded modules with initial-exec model TLS can only use surplus TLS. + +The new contract for surplus static TLS use is: + +- libc.so can have up to 192 bytes of IE TLS, +- other system libraries together can have up to 144 bytes of IE TLS. +- Some "optional" static TLS is available for opportunistic use. + +The optional TLS is now tunable: rtld.optional_static_tls, so users +can directly affect the allocated static TLS size. (Note that module +unloading with dlclose does not reclaim static TLS. After the optional +TLS runs out, TLS access is no longer optimized to use static TLS.) + +The default setting of rtld.optional_static_tls is 512 so the surplus +TLS is 3*192 + 4*144 + 512 = 1664 by default, the same as before. + +Fixes BZ #25051. + +Tested on aarch64-linux-gnu and x86_64-linux-gnu. + +Reviewed-by: Carlos O'Donell <carlos@redhat.com> +--- + csu/libc-tls.c | 3 ++ + elf/Makefile | 29 +++++++++++- + elf/dl-reloc.c | 37 +++++++++++---- + elf/dl-tls.c | 9 ++-- + elf/dl-tunables.list | 5 ++ + elf/dynamic-link.h | 5 +- + elf/tst-tls-ie-dlmopen.c | 112 +++++++++++++++++++++++++++++++++++++++++++++ + elf/tst-tls-ie-mod.h | 40 ++++++++++++++++ + elf/tst-tls-ie-mod0.c | 4 ++ + elf/tst-tls-ie-mod1.c | 4 ++ + elf/tst-tls-ie-mod2.c | 4 ++ + elf/tst-tls-ie-mod3.c | 4 ++ + elf/tst-tls-ie-mod4.c | 4 ++ + elf/tst-tls-ie-mod5.c | 4 ++ + elf/tst-tls-ie-mod6.c | 4 ++ + elf/tst-tls-ie.c | 111 ++++++++++++++++++++++++++++++++++++++++++++ + manual/tunables.texi | 17 +++++++ + sysdeps/generic/ldsodefs.h | 3 ++ + 18 files changed, 382 insertions(+), 17 deletions(-) + create mode 100644 elf/tst-tls-ie-dlmopen.c + create mode 100644 elf/tst-tls-ie-mod.h + create mode 100644 elf/tst-tls-ie-mod0.c + create mode 100644 elf/tst-tls-ie-mod1.c + create mode 100644 elf/tst-tls-ie-mod2.c + create mode 100644 elf/tst-tls-ie-mod3.c + create mode 100644 elf/tst-tls-ie-mod4.c + create mode 100644 elf/tst-tls-ie-mod5.c + create mode 100644 elf/tst-tls-ie-mod6.c + create mode 100644 elf/tst-tls-ie.c + +diff --git a/csu/libc-tls.c b/csu/libc-tls.c +index 28a7944..1b68d71 100644 +--- a/csu/libc-tls.c ++++ b/csu/libc-tls.c +@@ -59,6 +59,9 @@ size_t _dl_tls_static_size = 2048; + size_t _dl_tls_static_used; + /* Alignment requirement of the static TLS block. */ + size_t _dl_tls_static_align; ++/* Remaining amount of static TLS that may be used for optimizing ++ dynamic TLS access (e.g. with TLSDESC). */ ++size_t _dl_tls_static_optional = 512; + + /* Generation counter for the dtv. */ + size_t _dl_tls_generation; +diff --git a/elf/Makefile b/elf/Makefile +index 632a4d8..f440488 100644 +--- a/elf/Makefile ++++ b/elf/Makefile +@@ -201,7 +201,8 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \ + tst-unwind-ctor tst-unwind-main tst-audit13 \ + tst-sonamemove-link tst-sonamemove-dlopen tst-dlopen-tlsmodid \ + tst-dlopen-self tst-auditmany tst-initfinilazyfail tst-dlopenfail \ +- tst-dlopenfail-2 ++ tst-dlopenfail-2 \ ++ tst-tls-ie tst-tls-ie-dlmopen + # reldep9 + tests-internal += loadtest unload unload2 circleload1 \ + neededtest neededtest2 neededtest3 neededtest4 \ +@@ -312,7 +313,10 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ + tst-auditmanymod7 tst-auditmanymod8 tst-auditmanymod9 \ + tst-initlazyfailmod tst-finilazyfailmod \ + tst-dlopenfailmod1 tst-dlopenfaillinkmod tst-dlopenfailmod2 \ +- tst-dlopenfailmod3 tst-ldconfig-ld-mod ++ tst-dlopenfailmod3 tst-ldconfig-ld-mod \ ++ tst-tls-ie-mod0 tst-tls-ie-mod1 tst-tls-ie-mod2 \ ++ tst-tls-ie-mod3 tst-tls-ie-mod4 tst-tls-ie-mod5 \ ++ tst-tls-ie-mod6 + # Most modules build with _ISOMAC defined, but those filtered out + # depend on internal headers. + modules-names-tests = $(filter-out ifuncmod% tst-libc_dlvsym-dso tst-tlsmod%,\ +@@ -1699,3 +1703,23 @@ LDFLAGS-tst-dlopen-nodelete-reloc-mod17.so = -Wl,--no-as-needed + + $(objpfx)tst-ldconfig-ld_so_conf-update.out: $(objpfx)tst-ldconfig-ld-mod.so + $(objpfx)tst-ldconfig-ld_so_conf-update: $(libdl) ++ ++$(objpfx)tst-tls-ie: $(libdl) $(shared-thread-library) ++$(objpfx)tst-tls-ie.out: \ ++ $(objpfx)tst-tls-ie-mod0.so \ ++ $(objpfx)tst-tls-ie-mod1.so \ ++ $(objpfx)tst-tls-ie-mod2.so \ ++ $(objpfx)tst-tls-ie-mod3.so \ ++ $(objpfx)tst-tls-ie-mod4.so \ ++ $(objpfx)tst-tls-ie-mod5.so \ ++ $(objpfx)tst-tls-ie-mod6.so ++ ++$(objpfx)tst-tls-ie-dlmopen: $(libdl) $(shared-thread-library) ++$(objpfx)tst-tls-ie-dlmopen.out: \ ++ $(objpfx)tst-tls-ie-mod0.so \ ++ $(objpfx)tst-tls-ie-mod1.so \ ++ $(objpfx)tst-tls-ie-mod2.so \ ++ $(objpfx)tst-tls-ie-mod3.so \ ++ $(objpfx)tst-tls-ie-mod4.so \ ++ $(objpfx)tst-tls-ie-mod5.so \ ++ $(objpfx)tst-tls-ie-mod6.so +diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c +index ffcc84d..6d32e49 100644 +--- a/elf/dl-reloc.c ++++ b/elf/dl-reloc.c +@@ -39,13 +39,16 @@ + /* We are trying to perform a static TLS relocation in MAP, but it was + dynamically loaded. This can only work if there is enough surplus in + the static TLS area already allocated for each running thread. If this +- object's TLS segment is too big to fit, we fail. If it fits, +- we set MAP->l_tls_offset and return. +- This function intentionally does not return any value but signals error +- directly, as static TLS should be rare and code handling it should +- not be inlined as much as possible. */ ++ object's TLS segment is too big to fit, we fail with -1. If it fits, ++ we set MAP->l_tls_offset and return 0. ++ A portion of the surplus static TLS can be optionally used to optimize ++ dynamic TLS access (with TLSDESC or powerpc TLS optimizations). ++ If OPTIONAL is true then TLS is allocated for such optimization and ++ the caller must have a fallback in case the optional portion of surplus ++ TLS runs out. If OPTIONAL is false then the entire surplus TLS area is ++ considered and the allocation only fails if that runs out. */ + int +-_dl_try_allocate_static_tls (struct link_map *map) ++_dl_try_allocate_static_tls (struct link_map *map, bool optional) + { + /* If we've already used the variable with dynamic access, or if the + alignment requirements are too high, fail. */ +@@ -68,8 +71,14 @@ _dl_try_allocate_static_tls (struct link_map *map) + + size_t n = (freebytes - blsize) / map->l_tls_align; + +- size_t offset = GL(dl_tls_static_used) + (freebytes - n * map->l_tls_align +- - map->l_tls_firstbyte_offset); ++ /* Account optional static TLS surplus usage. */ ++ size_t use = freebytes - n * map->l_tls_align - map->l_tls_firstbyte_offset; ++ if (optional && use > GL(dl_tls_static_optional)) ++ goto fail; ++ else if (optional) ++ GL(dl_tls_static_optional) -= use; ++ ++ size_t offset = GL(dl_tls_static_used) + use; + + map->l_tls_offset = GL(dl_tls_static_used) = offset; + #elif TLS_DTV_AT_TP +@@ -83,6 +92,13 @@ _dl_try_allocate_static_tls (struct link_map *map) + if (used > GL(dl_tls_static_size)) + goto fail; + ++ /* Account optional static TLS surplus usage. */ ++ size_t use = used - GL(dl_tls_static_used); ++ if (optional && use > GL(dl_tls_static_optional)) ++ goto fail; ++ else if (optional) ++ GL(dl_tls_static_optional) -= use; ++ + map->l_tls_offset = offset; + map->l_tls_firstbyte_offset = GL(dl_tls_static_used); + GL(dl_tls_static_used) = used; +@@ -110,12 +126,15 @@ _dl_try_allocate_static_tls (struct link_map *map) + return 0; + } + ++/* This function intentionally does not return any value but signals error ++ directly, as static TLS should be rare and code handling it should ++ not be inlined as much as possible. */ + void + __attribute_noinline__ + _dl_allocate_static_tls (struct link_map *map) + { + if (map->l_tls_offset == FORCED_DYNAMIC_TLS_OFFSET +- || _dl_try_allocate_static_tls (map)) ++ || _dl_try_allocate_static_tls (map, false)) + { + _dl_signal_error (0, map->l_name, NULL, N_("\ + cannot allocate memory in static TLS block")); +diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h +index bb7a66f..6727233 100644 +--- a/elf/dynamic-link.h ++++ b/elf/dynamic-link.h +@@ -40,9 +40,10 @@ + (__builtin_expect ((sym_map)->l_tls_offset \ + != FORCED_DYNAMIC_TLS_OFFSET, 1) \ + && (__builtin_expect ((sym_map)->l_tls_offset != NO_TLS_OFFSET, 1) \ +- || _dl_try_allocate_static_tls (sym_map) == 0)) ++ || _dl_try_allocate_static_tls (sym_map, true) == 0)) + +-int _dl_try_allocate_static_tls (struct link_map *map) attribute_hidden; ++int _dl_try_allocate_static_tls (struct link_map *map, bool optional) ++ attribute_hidden; + + #include <elf.h> + +diff --git a/elf/tst-tls-ie-dlmopen.c b/elf/tst-tls-ie-dlmopen.c +new file mode 100644 +index 0000000..c7b5c68 +--- /dev/null ++++ b/elf/tst-tls-ie-dlmopen.c +@@ -0,0 +1,112 @@ ++/* Test dlopen of modules with initial-exec TLS after dlmopen. ++ Copyright (C) 2016-2020 Free Software Foundation, Inc. ++ This file is part of the GNU C Library. ++ ++ 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, see ++ <https://www.gnu.org/licenses/>. */ ++ ++/* This test tries to check that surplus static TLS is not used up for ++ dynamic TLS optimizations and 4*144 = 576 bytes of static TLS is ++ still available for dlopening modules with initial-exec TLS after 3 ++ new dlmopen namespaces are created. It depends on rtld.nns=4 and ++ rtld.optional_static_tls=512 tunable settings. */ ++ ++#include <errno.h> ++#include <pthread.h> ++#include <stdio.h> ++#include <stdlib.h> ++#include <string.h> ++ ++static int do_test (void); ++#include <support/xthread.h> ++#include <support/xdlfcn.h> ++#include <support/check.h> ++#include <support/test-driver.c> ++ ++/* Have some big TLS in the main exe: should not use surplus TLS. */ ++__thread char maintls[1000]; ++ ++static pthread_barrier_t barrier; ++ ++/* Forces multi-threaded behaviour. */ ++static void * ++blocked_thread_func (void *closure) ++{ ++ xpthread_barrier_wait (&barrier); ++ /* TLS load and access tests run here in the main thread. */ ++ xpthread_barrier_wait (&barrier); ++ return NULL; ++} ++ ++static void * ++load_and_access (Lmid_t lmid, const char *mod, const char *func) ++{ ++ /* Load module with TLS. */ ++ void *p = xdlmopen (lmid, mod, RTLD_NOW); ++ /* Access the TLS variable to ensure it is allocated. */ ++ void (*f) (void) = (void (*) (void))xdlsym (p, func); ++ f (); ++ return p; ++} ++ ++static int ++do_test (void) ++{ ++ void *mods[5]; ++ ++ { ++ int ret = pthread_barrier_init (&barrier, NULL, 2); ++ if (ret != 0) ++ { ++ errno = ret; ++ printf ("error: pthread_barrier_init: %m\n"); ++ exit (1); ++ } ++ } ++ ++ pthread_t blocked_thread = xpthread_create (NULL, blocked_thread_func, NULL); ++ xpthread_barrier_wait (&barrier); ++ ++ printf ("maintls[%zu]:\t %p .. %p\n", ++ sizeof maintls, maintls, maintls + sizeof maintls); ++ memset (maintls, 1, sizeof maintls); ++ ++ /* Load modules with dynamic TLS (use surplus static TLS for libc ++ in new namespaces and may be for TLS optimizations too). */ ++ mods[0] = load_and_access (LM_ID_BASE, "tst-tls-ie-mod0.so", "access0"); ++ mods[1] = load_and_access (LM_ID_NEWLM, "tst-tls-ie-mod1.so", "access1"); ++ mods[2] = load_and_access (LM_ID_NEWLM, "tst-tls-ie-mod2.so", "access2"); ++ mods[3] = load_and_access (LM_ID_NEWLM, "tst-tls-ie-mod3.so", "access3"); ++ /* Load modules with initial-exec TLS (can only use surplus static TLS). */ ++ mods[4] = load_and_access (LM_ID_BASE, "tst-tls-ie-mod6.so", "access6"); ++ ++ /* Here 576 bytes + 3 * libc use of surplus static TLS is in use so less ++ than 1024 bytes are available (exact number depends on TLS optimizations ++ and the libc TLS use). */ ++ printf ("The next dlmopen should fail...\n"); ++ void *p = dlmopen (LM_ID_BASE, "tst-tls-ie-mod4.so", RTLD_NOW); ++ if (p != NULL) ++ FAIL_EXIT1 ("error: expected dlmopen to fail because there is " ++ "not enough surplus static TLS.\n"); ++ printf ("...OK failed with: %s.\n", dlerror ()); ++ ++ xpthread_barrier_wait (&barrier); ++ xpthread_join (blocked_thread); ++ ++ /* Close the modules. */ ++ for (int i = 0; i < 5; ++i) ++ xdlclose (mods[i]); ++ ++ return 0; ++} +diff --git a/elf/tst-tls-ie-mod.h b/elf/tst-tls-ie-mod.h +new file mode 100644 +index 0000000..46b362a +--- /dev/null ++++ b/elf/tst-tls-ie-mod.h +@@ -0,0 +1,40 @@ ++/* Module with specified TLS size and model. ++ Copyright (C) 2020 Free Software Foundation, Inc. ++ This file is part of the GNU C Library. ++ ++ 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, see ++ <https://www.gnu.org/licenses/>. */ ++ ++/* This file is parameterized by macros N, SIZE and MODEL. */ ++ ++#include <stdio.h> ++#include <string.h> ++ ++#define CONCATX(x, y) x ## y ++#define CONCAT(x, y) CONCATX (x, y) ++#define STRX(x) #x ++#define STR(x) STRX (x) ++ ++#define VAR CONCAT (var, N) ++ ++__attribute__ ((aligned (8), tls_model (MODEL))) ++__thread char VAR[SIZE]; ++ ++void ++CONCAT (access, N) (void) ++{ ++ printf (STR (VAR) "[%d]:\t %p .. %p " MODEL "\n", SIZE, VAR, VAR + SIZE); ++ fflush (stdout); ++ memset (VAR, 1, SIZE); ++} +diff --git a/elf/tst-tls-ie-mod0.c b/elf/tst-tls-ie-mod0.c +new file mode 100644 +index 0000000..2450686 +--- /dev/null ++++ b/elf/tst-tls-ie-mod0.c +@@ -0,0 +1,4 @@ ++#define N 0 ++#define SIZE 480 ++#define MODEL "global-dynamic" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod1.c b/elf/tst-tls-ie-mod1.c +new file mode 100644 +index 0000000..849ff91 +--- /dev/null ++++ b/elf/tst-tls-ie-mod1.c +@@ -0,0 +1,4 @@ ++#define N 1 ++#define SIZE 120 ++#define MODEL "global-dynamic" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod2.c b/elf/tst-tls-ie-mod2.c +new file mode 100644 +index 0000000..23915ab +--- /dev/null ++++ b/elf/tst-tls-ie-mod2.c +@@ -0,0 +1,4 @@ ++#define N 2 ++#define SIZE 24 ++#define MODEL "global-dynamic" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod3.c b/elf/tst-tls-ie-mod3.c +new file mode 100644 +index 0000000..5395f84 +--- /dev/null ++++ b/elf/tst-tls-ie-mod3.c +@@ -0,0 +1,4 @@ ++#define N 3 ++#define SIZE 16 ++#define MODEL "global-dynamic" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod4.c b/elf/tst-tls-ie-mod4.c +new file mode 100644 +index 0000000..93ac2ea +--- /dev/null ++++ b/elf/tst-tls-ie-mod4.c +@@ -0,0 +1,4 @@ ++#define N 4 ++#define SIZE 1024 ++#define MODEL "initial-exec" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod5.c b/elf/tst-tls-ie-mod5.c +new file mode 100644 +index 0000000..84b3fd2 +--- /dev/null ++++ b/elf/tst-tls-ie-mod5.c +@@ -0,0 +1,4 @@ ++#define N 5 ++#define SIZE 128 ++#define MODEL "initial-exec" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie-mod6.c b/elf/tst-tls-ie-mod6.c +new file mode 100644 +index 0000000..c736bf0 +--- /dev/null ++++ b/elf/tst-tls-ie-mod6.c +@@ -0,0 +1,4 @@ ++#define N 6 ++#define SIZE 576 ++#define MODEL "initial-exec" ++#include "tst-tls-ie-mod.h" +diff --git a/elf/tst-tls-ie.c b/elf/tst-tls-ie.c +new file mode 100644 +index 0000000..2dc0894 +--- /dev/null ++++ b/elf/tst-tls-ie.c +@@ -0,0 +1,111 @@ ++/* Test dlopen of modules with initial-exec TLS. ++ Copyright (C) 2016-2020 Free Software Foundation, Inc. ++ This file is part of the GNU C Library. ++ ++ 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, see ++ <https://www.gnu.org/licenses/>. */ ++ ++/* This test tries to check that surplus static TLS is not used up for ++ dynamic TLS optimizations and 3*192 + 4*144 = 1152 bytes of static ++ TLS is available for dlopening modules with initial-exec TLS. It ++ depends on rtld.nns=4 and rtld.optional_static_tls=512 tunable setting. */ ++ ++#include <errno.h> ++#include <pthread.h> ++#include <stdio.h> ++#include <stdlib.h> ++#include <string.h> ++ ++static int do_test (void); ++#include <support/xthread.h> ++#include <support/xdlfcn.h> ++#include <support/check.h> ++#include <support/test-driver.c> ++ ++/* Have some big TLS in the main exe: should not use surplus TLS. */ ++__thread char maintls[1000]; ++ ++static pthread_barrier_t barrier; ++ ++/* Forces multi-threaded behaviour. */ ++static void * ++blocked_thread_func (void *closure) ++{ ++ xpthread_barrier_wait (&barrier); ++ /* TLS load and access tests run here in the main thread. */ ++ xpthread_barrier_wait (&barrier); ++ return NULL; ++} ++ ++static void * ++load_and_access (const char *mod, const char *func) ++{ ++ /* Load module with TLS. */ ++ void *p = xdlopen (mod, RTLD_NOW); ++ /* Access the TLS variable to ensure it is allocated. */ ++ void (*f) (void) = (void (*) (void))xdlsym (p, func); ++ f (); ++ return p; ++} ++ ++static int ++do_test (void) ++{ ++ void *mods[6]; ++ ++ { ++ int ret = pthread_barrier_init (&barrier, NULL, 2); ++ if (ret != 0) ++ { ++ errno = ret; ++ printf ("error: pthread_barrier_init: %m\n"); ++ exit (1); ++ } ++ } ++ ++ pthread_t blocked_thread = xpthread_create (NULL, blocked_thread_func, NULL); ++ xpthread_barrier_wait (&barrier); ++ ++ printf ("maintls[%zu]:\t %p .. %p\n", ++ sizeof maintls, maintls, maintls + sizeof maintls); ++ memset (maintls, 1, sizeof maintls); ++ ++ /* Load modules with dynamic TLS (may use surplus static TLS ++ opportunistically). */ ++ mods[0] = load_and_access ("tst-tls-ie-mod0.so", "access0"); ++ mods[1] = load_and_access ("tst-tls-ie-mod1.so", "access1"); ++ mods[2] = load_and_access ("tst-tls-ie-mod2.so", "access2"); ++ mods[3] = load_and_access ("tst-tls-ie-mod3.so", "access3"); ++ /* Load modules with initial-exec TLS (can only use surplus static TLS). */ ++ mods[4] = load_and_access ("tst-tls-ie-mod4.so", "access4"); ++ mods[5] = load_and_access ("tst-tls-ie-mod5.so", "access5"); ++ ++ /* Here 1152 bytes of surplus static TLS is in use and at most 512 bytes ++ are available (depending on TLS optimizations). */ ++ printf ("The next dlopen should fail...\n"); ++ void *p = dlopen ("tst-tls-ie-mod6.so", RTLD_NOW); ++ if (p != NULL) ++ FAIL_EXIT1 ("error: expected dlopen to fail because there is " ++ "not enough surplus static TLS.\n"); ++ printf ("...OK failed with: %s.\n", dlerror ()); ++ ++ xpthread_barrier_wait (&barrier); ++ xpthread_join (blocked_thread); ++ ++ /* Close the modules. */ ++ for (int i = 0; i < 6; ++i) ++ xdlclose (mods[i]); ++ ++ return 0; ++} +diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h +index eb3ef5b..ba114ab 100644 +--- a/sysdeps/generic/ldsodefs.h ++++ b/sysdeps/generic/ldsodefs.h +@@ -442,6 +442,9 @@ struct rtld_global + EXTERN size_t _dl_tls_static_used; + /* Alignment requirement of the static TLS block. */ + EXTERN size_t _dl_tls_static_align; ++ /* Remaining amount of static TLS that may be used for optimizing ++ dynamic TLS access (e.g. with TLSDESC). */ ++ EXTERN size_t _dl_tls_static_optional; + + /* Number of additional entries in the slotinfo array of each slotinfo + list element. A large number makes it almost certain take we never +-- +1.8.3.1 + |