mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 21:10:07 +00:00
* sysdeps/i386/tls.h (TLS_DO_MODIFY_LDT): Rewrite asm to use %ebx
optimally conditional on [__PIC__]. (TLS_DO_SET_THREAD_AREA): New macro, implement inline syscall without touching errno, and use latest modify_ldt-like interface. (TLS_SETUP_GS_SEGMENT): Use that instead of INLINE_SYSCALL. * sysdeps/i386/useldt.h (DO_MODIFY_LDT): Set %gs in this macro. (DO_SET_THREAD_AREA): New macro, uses current syscall interface with existing %gs value as the segment to set. (INIT_THREAD_SELF): Rewritten using those. Use set_thread_area only under [HAVE_TLS_SUPPORT] so we can rely on the initialization done by the first thread's early TLS setup.
This commit is contained in:
Roland McGrath
parent
c88b47593a
commit
25cb6eb229
@ -1,3 +1,17 @@
|
||||
2002-08-16 Roland McGrath <roland@redhat.com>
|
||||
|
||||
* sysdeps/i386/tls.h (TLS_DO_MODIFY_LDT): Rewrite asm to use %ebx
|
||||
optimally conditional on [__PIC__].
|
||||
(TLS_DO_SET_THREAD_AREA): New macro, implement inline syscall
|
||||
without touching errno, and use latest modify_ldt-like interface.
|
||||
(TLS_SETUP_GS_SEGMENT): Use that instead of INLINE_SYSCALL.
|
||||
* sysdeps/i386/useldt.h (DO_MODIFY_LDT): Set %gs in this macro.
|
||||
(DO_SET_THREAD_AREA): New macro, uses current syscall interface with
|
||||
existing %gs value as the segment to set.
|
||||
(INIT_THREAD_SELF): Rewritten using those. Use set_thread_area only
|
||||
under [HAVE_TLS_SUPPORT] so we can rely on the initialization done
|
||||
by the first thread's early TLS setup.
|
||||
|
||||
2002-08-15 Roland McGrath <roland@redhat.com>
|
||||
|
||||
* sysdeps/i386/tls.h (TLS_INIT_TP): Use statement expression and
|
||||
|
||||
@ -88,35 +88,59 @@ typedef struct
|
||||
# define GET_DTV(descr) \
|
||||
(((tcbhead_t *) (descr))->dtv)
|
||||
|
||||
# ifdef __PIC__
|
||||
# define TLS_EBX_ARG "r"
|
||||
# define TLS_LOAD_EBX "xchgl %3, %%ebx\n\t"
|
||||
# else
|
||||
# define TLS_EBX_ARG "b"
|
||||
# define TLS_LOAD_EBX
|
||||
# endif
|
||||
|
||||
# define TLS_DO_MODIFY_LDT(descr, nr) \
|
||||
({ \
|
||||
struct modify_ldt_ldt_s ldt_entry = \
|
||||
{ nr, (unsigned long int) (descr), sizeof (struct _pthread_descr_struct), \
|
||||
1, 0, 0, 0, 0, 1, 0 }; \
|
||||
int result; \
|
||||
asm volatile ( \
|
||||
"pushl %%ebx\n\t" \
|
||||
"movl $1, %%ebx\n\t" \
|
||||
"int $0x80\n\t" \
|
||||
"popl %%ebx" \
|
||||
: "=a" (result) \
|
||||
: "0" (__NR_modify_ldt), \
|
||||
/* The extra argument with the "m" constraint is necessary \
|
||||
to let the compiler know that we are accessing LDT_ENTRY here. */\
|
||||
"m" (ldt_entry), "c" (&ldt_entry), "d" (sizeof (ldt_entry))); \
|
||||
asm volatile (TLS_LOAD_EBX \
|
||||
"int $0x80\n\t" \
|
||||
TLS_LOAD_EBX \
|
||||
: "=a" (result) \
|
||||
: "0" (__NR_modify_ldt), \
|
||||
/* The extra argument with the "m" constraint is necessary \
|
||||
to let the compiler know that we are accessing LDT_ENTRY \
|
||||
here. */ \
|
||||
"m" (ldt_entry), TLS_EBX_ARG (1), "c" (&ldt_entry), \
|
||||
"d" (sizeof (ldt_entry))); \
|
||||
__builtin_expect (result, 0) != 0 ? -1 : nr * 8 + 7; \
|
||||
})
|
||||
|
||||
# define TLS_DO_SET_THREAD_AREA(descr) \
|
||||
({ \
|
||||
struct modify_ldt_ldt_s ldt_entry = \
|
||||
{ -1, (unsigned long int) (descr), sizeof (struct _pthread_descr_struct), \
|
||||
1, 0, 0, 0, 0, 1, 0 }; \
|
||||
int result; \
|
||||
asm volatile (TLS_LOAD_EBX \
|
||||
"int $0x80\n\t" \
|
||||
TLS_LOAD_EBX \
|
||||
: "=a" (result), "=m" (ldt_entry.entry_number) \
|
||||
: "0" (__NR_set_thread_area), \
|
||||
/* The extra argument with the "m" constraint is necessary \
|
||||
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 : -1; \
|
||||
})
|
||||
|
||||
# ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
|
||||
# define TLS_SETUP_GS_SEGMENT(descr) \
|
||||
INLINE_SYSCALL (set_thread_area, 2, descr, 1)
|
||||
# define TLS_SETUP_GS_SEGMENT(descr) TLS_DO_SET_THREAD_AREA (descr)
|
||||
# elif defined __NR_set_thread_area
|
||||
# define TLS_SETUP_GS_SEGMENT(descr) \
|
||||
({ int __seg = INLINE_SYSCALL (set_thread_area, 2, descr, 1); \
|
||||
({ int __seg = TLS_DO_SET_THREAD_AREA (descr); \
|
||||
__seg == -1 ? TLS_DO_MODIFY_LDT (descr, 0) : __seg; })
|
||||
# else
|
||||
# define TLS_SETUP_GS_SEGMENT(descr) \
|
||||
TLS_DO_MODIFY_LDT (descr, 0)
|
||||
# define TLS_SETUP_GS_SEGMENT(descr) TLS_DO_MODIFY_LDT ((descr), 0)
|
||||
# endif
|
||||
|
||||
/* Code to initially initialize the thread pointer. This might need
|
||||
|
||||
@ -62,49 +62,48 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t);
|
||||
__self; \
|
||||
})
|
||||
|
||||
#define DO_MODIFY_LDT(descr, nr) \
|
||||
|
||||
/* Initialize the thread-unique value. Two possible ways to do it. */
|
||||
|
||||
#define DO_MODIFY_LDT(descr, nr) \
|
||||
({ \
|
||||
struct modify_ldt_ldt_s ldt_entry = \
|
||||
{ nr, (unsigned long int) descr, sizeof (struct _pthread_descr_struct), \
|
||||
1, 0, 0, 0, 0, 1, 0 }; \
|
||||
if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) \
|
||||
abort (); \
|
||||
nr * 8 + 7; \
|
||||
asm ("movw %w0, %%gs" : : "q" (nr * 8 + 7)); \
|
||||
})
|
||||
|
||||
/* Initialize the thread-unique value. */
|
||||
#ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
|
||||
#define INIT_THREAD_SELF(descr, nr) \
|
||||
{ \
|
||||
int __gs = INLINE_SYSCALL (set_thread_area, 2, descr, 1); \
|
||||
if (__gs == -1) \
|
||||
abort (); \
|
||||
__asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs)); \
|
||||
}
|
||||
#elif defined __NR_set_thread_area
|
||||
/* When using the new set_thread_area call, we don't need to change %gs
|
||||
because we inherited the value set up in the main thread by TLS setup.
|
||||
We need to extract that value and set up the same segment in this
|
||||
thread. */
|
||||
# define DO_SET_THREAD_AREA(descr) \
|
||||
({ \
|
||||
int __gs; \
|
||||
struct modify_ldt_ldt_s ldt_entry = \
|
||||
{ ({ asm ("movw %%gs, %w0" : "=q" (__gs)); __gs >> 2; }), \
|
||||
(unsigned long int) descr, sizeof (struct _pthread_descr_struct), \
|
||||
1, 0, 0, 0, 0, 1, 0 }; \
|
||||
__builtin_expect (INLINE_SYSCALL (set_thread_area, 1, &ldt_entry) == 0, 1) \
|
||||
? __gs : -1; \
|
||||
})
|
||||
|
||||
#if defined __ASSUME_SET_THREAD_AREA_SYSCALL && defined HAVE_TLS_SUPPORT
|
||||
# define INIT_THREAD_SELF(descr, nr) DO_SET_THREAD_AREA (descr)
|
||||
#elif defined __NR_set_thread_area && defined HAVE_TLS_SUPPORT
|
||||
# define INIT_THREAD_SELF(descr, nr) \
|
||||
({ \
|
||||
if (__builtin_expect (__have_no_set_thread_area, 0) \
|
||||
|| (DO_SET_THREAD_AREA (descr) == -1 \
|
||||
&& (__have_no_set_thread_area = 1))) \
|
||||
DO_MODIFY_LDT (descr, nr); \
|
||||
})
|
||||
/* Defined in pspinlock.c. */
|
||||
extern int __have_no_set_thread_area;
|
||||
|
||||
#define INIT_THREAD_SELF(descr, nr) \
|
||||
{ \
|
||||
int __gs = -1; \
|
||||
if (! __builtin_expect (__have_no_set_thread_area, 0)) \
|
||||
{ \
|
||||
if ((__gs = INLINE_SYSCALL (set_thread_area, 2, descr, 1)) == -1 \
|
||||
&& errno == ENOSYS) \
|
||||
__have_no_set_thread_area = 1; \
|
||||
} \
|
||||
if (__builtin_expect (__gs == -1, 0)) \
|
||||
__gs = DO_MODIFY_LDT (descr, nr); \
|
||||
__asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs)); \
|
||||
}
|
||||
#else
|
||||
#define INIT_THREAD_SELF(descr, nr) \
|
||||
{ \
|
||||
int __gs = DO_MODIFY_LDT (descr, nr); \
|
||||
__asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs)); \
|
||||
}
|
||||
# define INIT_THREAD_SELF(descr, nr) DO_MODIFY_LDT (descr, nr)
|
||||
#endif
|
||||
|
||||
/* Free resources associated with thread descriptor. */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user