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Diffstat (limited to 'linuxthreads/sysdeps/i386/tls.h')
-rw-r--r--linuxthreads/sysdeps/i386/tls.h47
1 files changed, 23 insertions, 24 deletions
diff --git a/linuxthreads/sysdeps/i386/tls.h b/linuxthreads/sysdeps/i386/tls.h
index 8bbe5f28e6..c244801bf4 100644
--- a/linuxthreads/sysdeps/i386/tls.h
+++ b/linuxthreads/sysdeps/i386/tls.h
@@ -106,20 +106,18 @@ typedef struct
# endif
# if __ASSUME_LDT_WORKS > 0
-# define TLS_DO_MODIFY_LDT_KERNEL_CHECK /* Nothing to do. */
+# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) (doit) /* Nothing to check. */
# else
# include "useldt.h" /* For the structure. */
-# define TLS_DO_MODIFY_LDT_KERNEL_CHECK \
- if (__builtin_expect (GL(dl_osversion) < 131939, 0)) \
- _dl_fatal_printf ("kernel %u.%u.%u cannot support thread-local storage\n",\
- (GL(dl_osversion) >> 16) & 0xff, \
- (GL(dl_osversion) >> 8) & 0xff, \
- (GL(dl_osversion) >> 0) & 0xff);
+# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) \
+ (__builtin_expect (GL(dl_osversion) < 131939, 0) \
+ ? "kernel too old for thread-local storage support" \
+ : (doit))
# endif
# define TLS_DO_MODIFY_LDT(descr, nr) \
+TLS_DO_MODIFY_LDT_KERNEL_CHECK( \
({ \
- TLS_DO_MODIFY_LDT_KERNEL_CHECK \
struct modify_ldt_ldt_s ldt_entry = \
{ nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
1, 0, 0, 1, 0, 1, 0 }; \
@@ -134,8 +132,10 @@ typedef struct
here. */ \
"m" (ldt_entry), TLS_EBX_ARG (1), "c" (&ldt_entry), \
"d" (sizeof (ldt_entry))); \
- __builtin_expect (result, 0) != 0 ? -1 : nr * 8 + 7; \
-})
+ __builtin_expect (result, 0) == 0 \
+ ? ({ asm ("movw %w0, %%gs" : : "q" ((nr) * 8 + 7)); NULL; }) \
+ : "cannot set up LDT for thread-local storage"; \
+}))
# define TLS_DO_SET_THREAD_AREA(descr, secondcall) \
({ \
@@ -156,41 +156,40 @@ typedef struct
to let the compiler know that we are accessing LDT_ENTRY \
here. */ \
TLS_EBX_ARG (&ldt_entry), "m" (ldt_entry)); \
- __builtin_expect (result, 0) == 0 ? ldt_entry.entry_number * 8 + 3 : -1; \
+ if (__builtin_expect (result, 0) == 0) \
+ asm ("movw %w0, %%gs" : : "q" (ldt_entry.entry_number * 8 + 3)); \
+ result; \
})
# ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
-# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
- TLS_DO_SET_THREAD_AREA (descr, firstcall)
+# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
+ (TLS_DO_SET_THREAD_AREA (descr, firstcall) \
+ ? "set_thread_area failed when setting up thread-local storage" : NULL)
# elif defined __NR_set_thread_area
# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
- ({ int __seg = TLS_DO_SET_THREAD_AREA (descr, secondcall); \
- __seg == -1 ? TLS_DO_MODIFY_LDT (descr, 0) : __seg; })
+ (TLS_DO_SET_THREAD_AREA (descr, secondcall) \
+ ? TLS_DO_MODIFY_LDT (descr, 0) : NULL)
# else
# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
TLS_DO_MODIFY_LDT ((descr), 0)
# 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. */
+ operation can cause a failure 'errno' must not be touched.
+
+ The value of this macro is null if successful, or an error string. */
# 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; \
\
- __gs = TLS_SETUP_GS_SEGMENT (_descr, secondcall); \
- if (__builtin_expect (__gs, 7) != -1) \
- { \
- asm ("movw %w0, %%gs" : : "q" (__gs)); \
- __gs = 0; \
- } \
- __gs; \
+ TLS_SETUP_GS_SEGMENT (_descr, secondcall); \
})