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Add ARM TLS support
- From: Daniel Jacobowitz <drow at false dot org>
- To: libc-ports at sourceware dot org, pb at reciva dot com
- Date: Wed, 5 Oct 2005 12:56:31 -0400
- Subject: Add ARM TLS support
The last ARM patch required to build current glibc. This patch implements
thread local storage support for LinuxThreads, since it is now mandatory
(memusage needs it).
CVS binutils already includes the necessary infrastructure; CVS GCC does
not, but the csl-arm-branch compiler does, and I've posted a version for
HEAD this morning. I've tested it on arm-none-linux-gnu using gcc HEAD and
that patch.
OK to apply?
--
Daniel Jacobowitz
CodeSourcery, LLC
2005-10-05 Daniel Jacobowitz <dan@codesourcery.com>
* sysdeps/arm/dl-machine.h: Include <tls.h>.
(elf_machine_type_class, elf_machine_rel, elf_machine_rela): Handle
TLS relocations.
* sysdeps/unix/sysv/linux/arm/Makefile: Build __aeabi_read_tp.
* sysdeps/unix/sysv/linux/arm/sysdep.h (INTERNAL_SYSCALL_RAW): Renamed
from INTERNAL_SYSCALL.
(INTERNAL_SYSCALL, INTERNAL_SYSCALL_ARM): New macros.
* sysdeps/arm/dl-tls.h, sysdeps/arm/elf/configure.in,
sysdeps/arm/elf/configure, sysdeps/arm/libc-tls.c,
sysdeps/arm/linuxthreads/tls.h, sysdeps/arm/tls-macros.h,
sysdeps/unix/sysv/linux/arm/aeabi_read_tp.S,
sysdeps/unix/sysv/linux/arm/libc-aeabi_read_tp.S: New files.
Index: glibc/ports/sysdeps/arm/dl-machine.h
===================================================================
--- glibc.orig/ports/sysdeps/arm/dl-machine.h 2005-10-04 14:19:24.000000000 -0400
+++ glibc/ports/sysdeps/arm/dl-machine.h 2005-10-04 14:19:25.000000000 -0400
@@ -24,6 +24,7 @@
#define ELF_MACHINE_NAME "ARM"
#include <sys/param.h>
+#include <tls.h>
#define VALID_ELF_ABIVERSION(ver) (ver == 0)
#define VALID_ELF_OSABI(osabi) \
@@ -193,13 +194,22 @@ _dl_start_user:\n\
.previous\n\
");
-/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so
- PLT entries should not be allowed to define the value.
+/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
+ TLS variable, so undefined references should not be allowed to
+ define the value.
ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one
of the main executable's symbols, as for a COPY reloc. */
+#if defined USE_TLS && (!defined RTLD_BOOTSTRAP || USE___THREAD)
+# define elf_machine_type_class(type) \
+ ((((type) == R_ARM_JUMP_SLOT || (type) == R_ARM_TLS_DTPMOD32 \
+ || (type) == R_ARM_TLS_DTPOFF32 || (type) == R_ARM_TLS_TPOFF32) \
+ * ELF_RTYPE_CLASS_PLT) \
+ | (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY))
+#else
#define elf_machine_type_class(type) \
((((type) == R_ARM_JUMP_SLOT) * ELF_RTYPE_CLASS_PLT) \
| (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY))
+#endif
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_ARM_JUMP_SLOT
@@ -399,7 +409,24 @@ elf_machine_rel (struct link_map *map, c
value = (*reloc_addr & 0xff000000) | (newvalue & 0x00ffffff);
*reloc_addr = value;
}
- break;
+ break;
+#if defined USE_TLS && !defined RTLD_BOOTSTRAP
+ case R_ARM_TLS_DTPMOD32:
+ /* Get the information from the link map returned by the
+ resolv function. */
+ if (sym_map != NULL)
+ *reloc_addr = sym_map->l_tls_modid;
+ break;
+
+ case R_ARM_TLS_DTPOFF32:
+ *reloc_addr += sym->st_value;
+ break;
+
+ case R_ARM_TLS_TPOFF32:
+ CHECK_STATIC_TLS (map, sym_map);
+ *reloc_addr += sym->st_value + sym_map->l_tls_offset;
+ break;
+#endif
default:
_dl_reloc_bad_type (map, r_type, 0);
break;
@@ -480,6 +507,24 @@ elf_machine_rela (struct link_map *map,
*reloc_addr = value;
}
break;
+#if defined USE_TLS && !defined RTLD_BOOTSTRAP
+ case R_ARM_TLS_DTPMOD32:
+ /* Get the information from the link map returned by the
+ resolv function. */
+ if (sym_map != NULL)
+ *reloc_addr = sym_map->l_tls_modid;
+ break;
+
+ case R_ARM_TLS_DTPOFF32:
+ *reloc_addr = sym->st_value + reloc->r_addend;
+ break;
+
+ case R_ARM_TLS_TPOFF32:
+ CHECK_STATIC_TLS (map, sym_map);
+ *reloc_addr = (sym->st_value + sym_map->l_tls_offset
+ + reloc->r_addend);
+ break;
+#endif
default:
_dl_reloc_bad_type (map, r_type, 0);
break;
Index: glibc/ports/sysdeps/arm/dl-tls.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/arm/dl-tls.h 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1,29 @@
+/* Thread-local storage handling in the ELF dynamic linker. ARM version.
+ Copyright (C) 2005 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+
+/* Type used for the representation of TLS information in the GOT. */
+typedef struct
+{
+ unsigned long int ti_module;
+ unsigned long int ti_offset;
+} tls_index;
+
+
+extern void *__tls_get_addr (tls_index *ti);
Index: glibc/ports/sysdeps/arm/elf/configure.in
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/arm/elf/configure.in 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1,35 @@
+GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
+# Local configure fragment for sysdeps/arm/elf.
+
+if test "$usetls" != no; then
+# Check for support of thread-local storage handling in assembler and
+# linker.
+AC_CACHE_CHECK(for ARM TLS support, libc_cv_arm_tls, [dnl
+cat > conftest.s <<\EOF
+ .section ".tdata", "awT", %progbits
+ .globl foo
+foo: .long 1
+ .section ".tbss", "awT", %nobits
+ .globl bar
+bar: .skip 4
+ .text
+.word foo(tpoff)
+.word foo(tlsgd)
+EOF
+dnl
+if AC_TRY_COMMAND(${CC-cc} -c $CFLAGS conftest.s 1>&AS_MESSAGE_LOG_FD); then
+ libc_cv_arm_tls=yes
+else
+ libc_cv_arm_tls=no
+fi
+rm -f conftest*])
+if test $libc_cv_arm_tls = yes; then
+ AC_DEFINE(HAVE_TLS_SUPPORT)
+fi
+fi
+
+dnl It is always possible to access static and hidden symbols in an
+dnl position independent way.
+dnl NOTE: This feature was added by the GCC TLS patches. We should test for
+dnl it. Until we do, don't define it.
+#AC_DEFINE(PI_STATIC_AND_HIDDEN)
Index: glibc/ports/sysdeps/arm/libc-tls.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/arm/libc-tls.c 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1,37 @@
+/* Thread-local storage handling in the ELF dynamic linker. ARM version.
+ Copyright (C) 2005 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdeps/generic/libc-tls.c>
+#include <dl-tls.h>
+
+#if USE_TLS
+
+/* On ARM, linker optimizations are not required, so __tls_get_addr
+ can be called even in statically linked binaries. In this case module
+ must be always 1 and PT_TLS segment exist in the binary, otherwise it
+ would not link. */
+
+void *
+__tls_get_addr (tls_index *ti)
+{
+ dtv_t *dtv = THREAD_DTV ();
+ return (char *) dtv[1].pointer.val + ti->ti_offset;
+}
+
+#endif
Index: glibc/ports/sysdeps/arm/linuxthreads/tls.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/arm/linuxthreads/tls.h 2005-10-04 14:24:36.000000000 -0400
@@ -0,0 +1,172 @@
+/* Definitions for thread-local data handling. linuxthreads/ARM version.
+ Copyright (C) 2004 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _TLS_H
+#define _TLS_H
+
+#ifndef __ASSEMBLER__
+
+# include <stdbool.h>
+# include <pt-machine.h>
+# include <stddef.h>
+
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ struct
+ {
+ void *val;
+ bool is_static;
+ } pointer;
+} dtv_t;
+
+typedef struct
+{
+ dtv_t *dtv;
+
+ /* Reserved for the thread implementation. Unused in LinuxThreads. */
+ void *private;
+} tcbhead_t;
+#endif
+
+
+/* We can support TLS only if the floating-stack support is available.
+ However, we want to compile in the support and test at runtime whether
+ the running kernel can support it or not. To avoid bothering with the
+ TLS support code at all, use configure --without-tls.
+
+ We need USE_TLS to be consistently defined, for ldsodefs.h conditionals.
+ But some of the code below can cause problems in building libpthread
+ (e.g. useldt.h will defined FLOATING_STACKS when it shouldn't). */
+
+/* LinuxThreads can only support TLS if both floating stacks and support
+ from the tools are available.
+
+ We have to define USE_TLS consistently, or ldsodefs.h will lay out types
+ differently between an NPTL build and a LinuxThreads build. It can be set
+ for libc.so and not libpthread.so, but only if we provide appropriate padding
+ in the _pthread_descr_struct.
+
+ Currently nothing defines FLOATING_STACKS. We could assume this based on
+ kernel version once the TLS patches are available in kernel.org.
+
+ To avoid bothering with the TLS support code at all, use configure
+ --without-tls. */
+
+#if defined HAVE_TLS_SUPPORT \
+ && (defined FLOATING_STACKS || !defined IS_IN_libpthread)
+
+/* Signal that TLS support is available. */
+# define USE_TLS 1
+
+/* Include padding in _pthread_descr_struct so that libc can find p_errno,
+ if libpthread will only include the padding because of the !IS_IN_libpthread
+ check. */
+#ifndef FLOATING_STACKS
+# define INCLUDE_TLS_PADDING 1
+#endif
+
+# ifndef __ASSEMBLER__
+/* Get system call information. */
+# include <sysdep.h>
+
+/* This is the size of the initial TCB. */
+# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
+
+/* Alignment requirements for the initial TCB. */
+# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
+
+/* This is the size of the TCB. */
+# define TLS_TCB_SIZE sizeof (tcbhead_t)
+
+/* Alignment requirements for the TCB. */
+# define TLS_TCB_ALIGN __alignof__ (tcbhead_t)
+
+/* This is the size we need before TCB. */
+# define TLS_PRE_TCB_SIZE sizeof (struct _pthread_descr_struct)
+
+/* The DTV is allocated at the TP; the TCB is placed elsewhere. */
+# define TLS_DTV_AT_TP 1
+
+/* Install the dtv pointer. The pointer passed is to the element with
+ index -1 which contain the length. */
+# define INSTALL_DTV(TCBP, DTVP) \
+ (((tcbhead_t *) (TCBP))->dtv = (DTVP) + 1)
+
+/* Install new dtv for current thread. */
+# define INSTALL_NEW_DTV(DTV) \
+ (((tcbhead_t *)__builtin_thread_pointer ())->dtv = (DTV))
+
+/* Return dtv of given thread descriptor. */
+# define GET_DTV(TCBP) \
+ (((tcbhead_t *) (TCBP))->dtv)
+
+/* Code to initially initialize the thread pointer. This might need
+ special attention since 'errno' is not yet available and if the
+ operation can cause a failure 'errno' must not be touched. */
+# define TLS_INIT_TP(TCBP, SECONDCALL) \
+ ({ INTERNAL_SYSCALL_DECL (err); \
+ long result_var; \
+ result_var = INTERNAL_SYSCALL_ARM (set_tls, err, 1, (TCBP)); \
+ INTERNAL_SYSCALL_ERROR_P (result_var, err) \
+ ? "unknown error" : NULL; })
+
+/* Return the address of the dtv for the current thread. */
+# define THREAD_DTV() \
+ (((tcbhead_t *)__builtin_thread_pointer ())->dtv)
+
+/* Return the thread descriptor for the current thread. */
+# undef THREAD_SELF
+# define THREAD_SELF \
+ ((pthread_descr)__builtin_thread_pointer () - 1)
+
+# undef INIT_THREAD_SELF
+# define INIT_THREAD_SELF(DESCR, NR) \
+ TLS_INIT_TP ((struct _pthread_descr_struct *)(DESCR) + 1, 0)
+
+/* Get the thread descriptor definition. */
+# include <linuxthreads/descr.h>
+
+/* ??? Generic bits of LinuxThreads may call these macros with
+ DESCR set to NULL. We are expected to be able to reference
+ the "current" value.
+
+ In our case, we'd really prefer to use DESCR, since lots of
+ PAL_code calls would be expensive. We can only trust that
+ the compiler does its job and unifies the multiple
+ __builtin_thread_pointer instances. */
+
+#define THREAD_GETMEM(descr, member) \
+ ((void) sizeof (descr), THREAD_SELF->member)
+#define THREAD_GETMEM_NC(descr, member) \
+ ((void) sizeof (descr), THREAD_SELF->member)
+#define THREAD_SETMEM(descr, member, value) \
+ ((void) sizeof (descr), THREAD_SELF->member = (value))
+#define THREAD_SETMEM_NC(descr, member, value) \
+ ((void) sizeof (descr), THREAD_SELF->member = (value))
+
+/* Initializing the thread pointer will generate a SIGILL if the syscall
+ is not available. */
+#define TLS_INIT_TP_EXPENSIVE 1
+
+# endif /* HAVE_TLS_SUPPORT */
+#endif /* __ASSEMBLER__ */
+
+#endif /* tls.h */
Index: glibc/ports/sysdeps/arm/tls-macros.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/arm/tls-macros.h 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1,51 @@
+#define TLS_LE(x) \
+ ({ int *__result; \
+ void *tp = __builtin_thread_pointer (); \
+ asm ("ldr %0, 1f; " \
+ "add %0, %1, %0; " \
+ "b 2f; " \
+ "1: .word " #x "(tpoff); " \
+ "2: " \
+ : "=&r" (__result) : "r" (tp)); \
+ __result; })
+
+#define TLS_IE(x) \
+ ({ int *__result; \
+ void *tp = __builtin_thread_pointer (); \
+ asm ("ldr %0, 1f; " \
+ "3: ldr %0, [pc, %0];" \
+ "add %0, %1, %0; " \
+ "b 2f; " \
+ "1: .word " #x "(gottpoff) + (. - 3b - 8); " \
+ "2: " \
+ : "=&r" (__result) : "r" (tp)); \
+ __result; })
+
+#define TLS_LD(x) \
+ ({ char *__result; \
+ int __offset; \
+ extern void *__tls_get_addr (void *); \
+ asm ("ldr %0, 2f; " \
+ "1: add %0, pc, %0; " \
+ "b 3f; " \
+ "2: .word " #x "(tlsldm) + (. - 1b - 8); " \
+ "3: " \
+ : "=r" (__result)); \
+ __result = (char *)__tls_get_addr (__result); \
+ asm ("ldr %0, 1f; " \
+ "b 2f; " \
+ "1: .word " #x "(tlsldo); " \
+ "2: " \
+ : "=r" (__offset)); \
+ (int *) (__result + __offset); })
+
+#define TLS_GD(x) \
+ ({ int *__result; \
+ extern void *__tls_get_addr (void *); \
+ asm ("ldr %0, 2f; " \
+ "1: add %0, pc, %0; " \
+ "b 3f; " \
+ "2: .word " #x "(tlsgd) + (. - 1b - 8); " \
+ "3: " \
+ : "=r" (__result)); \
+ (int *)__tls_get_addr (__result); })
Index: glibc/ports/sysdeps/unix/sysv/linux/arm/Makefile
===================================================================
--- glibc.orig/ports/sysdeps/unix/sysv/linux/arm/Makefile 2005-10-04 14:19:24.000000000 -0400
+++ glibc/ports/sysdeps/unix/sysv/linux/arm/Makefile 2005-10-04 14:19:25.000000000 -0400
@@ -1,3 +1,13 @@
+ifeq ($(subdir),csu)
+sysdep_routines += aeabi_read_tp libc-aeabi_read_tp
+static-only-routines += aeabi_read_tp
+shared-only-routines += libc-aeabi_read_tp
+endif
+
+ifeq ($(subdir),elf)
+sysdep-rtld-routines += aeabi_read_tp
+endif
+
ifeq ($(subdir),misc)
sysdep_routines += ioperm
sysdep_headers += sys/elf.h sys/io.h
Index: glibc/ports/sysdeps/unix/sysv/linux/arm/aeabi_read_tp.S
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/unix/sysv/linux/arm/aeabi_read_tp.S 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1,34 @@
+/* Copyright (C) 2005 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+
+#ifdef HAVE_TLS_SUPPORT
+
+/* GCC will emit calls to this routine under -mtp=soft. Linux has an
+ equivalent helper function (which clobbers fewer registers than
+ a normal function call) in a high page of memory; tail call to the
+ helper. */
+
+ .hidden __aeabi_read_tp
+ENTRY (__aeabi_read_tp)
+ mov r0, #0xffff0fff
+ sub pc, r0, #31
+END (__aeabi_read_tp)
+
+#endif
Index: glibc/ports/sysdeps/unix/sysv/linux/arm/libc-aeabi_read_tp.S
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ glibc/ports/sysdeps/unix/sysv/linux/arm/libc-aeabi_read_tp.S 2005-10-04 14:19:25.000000000 -0400
@@ -0,0 +1 @@
+#include <aeabi_read_tp.S>
Index: glibc/ports/sysdeps/unix/sysv/linux/arm/sysdep.h
===================================================================
--- glibc.orig/ports/sysdeps/unix/sysv/linux/arm/sysdep.h 2005-06-09 17:48:16.000000000 -0400
+++ glibc/ports/sysdeps/unix/sysv/linux/arm/sysdep.h 2005-10-04 14:27:38.000000000 -0400
@@ -179,20 +179,28 @@ __local_syscall_error: \
#undef INTERNAL_SYSCALL_DECL
#define INTERNAL_SYSCALL_DECL(err) do { } while (0)
-#undef INTERNAL_SYSCALL
-#define INTERNAL_SYSCALL(name, err, nr, args...) \
+#undef INTERNAL_SYSCALL_RAW
+#define INTERNAL_SYSCALL_RAW(name, err, nr, args...) \
({ unsigned int _sys_result; \
{ \
register int _a1 asm ("a1"); \
LOAD_ARGS_##nr (args) \
asm volatile ("swi %1 @ syscall " #name \
: "=r" (_a1) \
- : "i" (SYS_ify(name)) ASM_ARGS_##nr \
+ : "i" (name) ASM_ARGS_##nr \
: "memory"); \
_sys_result = _a1; \
} \
(int) _sys_result; })
+#undef INTERNAL_SYSCALL
+#define INTERNAL_SYSCALL(name, err, nr, args...) \
+ INTERNAL_SYSCALL_RAW(SYS_ify(name), err, nr, args)
+
+#undef INTERNAL_SYSCALL_ARM
+#define INTERNAL_SYSCALL_ARM(name, err, nr, args...) \
+ INTERNAL_SYSCALL_RAW(__ARM_NR_##name, err, nr, args)
+
#undef INTERNAL_SYSCALL_ERROR_P
#define INTERNAL_SYSCALL_ERROR_P(val, err) \
((unsigned int) (val) >= 0xfffff001u)