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authorWaldemar Brodkorb <wbx@uclibc-ng.org>2016-05-18 18:41:24 +0200
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2016-05-18 18:41:24 +0200
commit6a8ccc95528f5e86a8770ed15ce89609b5b3dee9 (patch)
treebbd4df35b4d4a6a8b00d7a5e61fb2668b850ad62 /libpthread/linuxthreads/sysdeps/i386/tls.h
parent398a27a5b323956344b4f831d892fed3bd9813c7 (diff)
remove linuxthreads.new, rename linuxthreads.old
Linuxthreads.new isn't really useful with the existence of NPTL/TLS for well supported architectures. There is no reason to use LT.new for ARM/MIPS or other architectures supporting NPTL/TLS. It is not available for noMMU architectures like Blackfin or FR-V. To simplify the live of the few uClibc-ng developers, LT.new is removed and LT.old is renamed to LT. LINUXTHREADS_OLD -> UCLIBC_HAS_LINUXTHREADS
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/i386/tls.h')
-rw-r--r--libpthread/linuxthreads/sysdeps/i386/tls.h84
1 files changed, 21 insertions, 63 deletions
diff --git a/libpthread/linuxthreads/sysdeps/i386/tls.h b/libpthread/linuxthreads/sysdeps/i386/tls.h
index d79bf0779..4469f0776 100644
--- a/libpthread/linuxthreads/sysdeps/i386/tls.h
+++ b/libpthread/linuxthreads/sysdeps/i386/tls.h
@@ -30,11 +30,7 @@
typedef union dtv
{
size_t counter;
- struct
- {
- void *val;
- bool is_static;
- } pointer;
+ void *pointer;
} dtv_t;
@@ -44,28 +40,15 @@ typedef struct
thread descriptor used by libpthread. */
dtv_t *dtv;
void *self; /* Pointer to the thread descriptor. */
- int multiple_threads;
- uintptr_t sysinfo;
} tcbhead_t;
-
-#else /* __ASSEMBLER__ */
-# include <tcb-offsets.h>
#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). */
-#if defined HAVE_TLS_SUPPORT \
- && (defined FLOATING_STACKS || !defined IS_IN_libpthread)
+/* We can support TLS only if the floating-stack support is available. */
+#if defined FLOATING_STACKS && defined HAVE_TLS_SUPPORT
/* Signal that TLS support is available. */
-# define USE_TLS 1
+//# define USE_TLS 1
# ifndef __ASSEMBLER__
/* Get system call information. */
@@ -114,20 +97,7 @@ typedef struct
# define TLS_LOAD_EBX
# endif
-# if !defined IS_IN_libpthread && !defined DO_MODIFY_LDT
-# include "useldt.h" /* For the structure. */
-# endif
-# if __ASSUME_LDT_WORKS > 0
-# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) (doit) /* Nothing to check. */
-# else
-# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) \
- (__builtin_expect (GLRO(dl_osversion) < 131939, 0) \
- ? "kernel too old for thread-local storage support\n" \
- : (doit))
-# endif
-
# define TLS_DO_MODIFY_LDT(descr, nr) \
-TLS_DO_MODIFY_LDT_KERNEL_CHECK( \
({ \
struct modify_ldt_ldt_s ldt_entry = \
{ nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
@@ -143,10 +113,8 @@ TLS_DO_MODIFY_LDT_KERNEL_CHECK( \
here. */ \
"m" (ldt_entry), TLS_EBX_ARG (1), "c" (&ldt_entry), \
"d" (sizeof (ldt_entry))); \
- __builtin_expect (result, 0) == 0 \
- ? ({ __asm__ ("movw %w0, %%gs" : : "q" ((nr) * 8 + 7)); NULL; }) \
- : "cannot set up LDT for thread-local storage\n"; \
-}))
+ __builtin_expect (result, 0) != 0 ? -1 : nr * 8 + 7; \
+})
# define TLS_DO_SET_THREAD_AREA(descr, secondcall) \
({ \
@@ -167,60 +135,50 @@ TLS_DO_MODIFY_LDT_KERNEL_CHECK( \
to let the compiler know that we are accessing LDT_ENTRY \
here. */ \
TLS_EBX_ARG (&ldt_entry), "m" (ldt_entry)); \
- if (__builtin_expect (result, 0) == 0) \
- __asm__ ("movw %w0, %%gs" : : "q" (ldt_entry.entry_number * 8 + 3)); \
- result; \
+ __builtin_expect (result, 0) == 0 ? ldt_entry.entry_number * 8 + 3 : -1; \
})
# ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
-# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
- (TLS_DO_SET_THREAD_AREA (descr, secondcall) \
- ? "set_thread_area failed when setting up thread-local storage\n" : NULL)
+# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
+ TLS_DO_SET_THREAD_AREA (descr, firstcall)
# elif defined __NR_set_thread_area
# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
- (TLS_DO_SET_THREAD_AREA (descr, secondcall) \
- ? TLS_DO_MODIFY_LDT (descr, 0) : NULL)
+ ({ int __seg = TLS_DO_SET_THREAD_AREA (descr, secondcall); \
+ __seg == -1 ? TLS_DO_MODIFY_LDT (descr, 0) : __seg; })
# else
# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
TLS_DO_MODIFY_LDT ((descr), 0)
# endif
-#if defined NEED_DL_SYSINFO
-# define INIT_SYSINFO \
- head->sysinfo = GLRO(dl_sysinfo)
-#else
-# define INIT_SYSINFO
-#endif
-
/* 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.
-
- The value of this macro is null if successful, or an error string. */
+ operation can cause a failure 'errno' must not be touched. */
# define TLS_INIT_TP(descr, secondcall) \
({ \
void *_descr = (descr); \
tcbhead_t *head = _descr; \
+ int __gs; \
\
head->tcb = _descr; \
/* For now the thread descriptor is at the same address. */ \
head->self = _descr; \
\
- INIT_SYSINFO; \
- TLS_SETUP_GS_SEGMENT (_descr, secondcall); \
+ __gs = TLS_SETUP_GS_SEGMENT (_descr, secondcall); \
+ if (__builtin_expect (__gs, 7) != -1) \
+ { \
+ __asm__ ("movw %w0, %%gs" : : "q" (__gs)); \
+ __gs = 0; \
+ } \
+ __gs; \
})
-/* Indicate that dynamic linker shouldn't try to initialize TLS even
- when no PT_TLS segments are found in the program and libraries
- it is linked against. */
-# define TLS_INIT_TP_EXPENSIVE 1
/* Return the address of the dtv for the current thread. */
# define THREAD_DTV() \
({ struct _pthread_descr_struct *__descr; \
THREAD_GETMEM (__descr, p_header.data.dtvp); })
-# endif /* HAVE_TLS_SUPPORT && (FLOATING_STACKS || !IS_IN_libpthread) */
+# endif /* FLOATING_STACKS && HAVE_TLS_SUPPORT */
#endif /* __ASSEMBLER__ */
#endif /* tls.h */