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| author | Ulrich Drepper <drepper@redhat.com> | 2002-08-02 01:11:43 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2002-08-02 01:11:43 +0000 |
| commit | d7e1ad053b0d742f4f9c632dc0c5feb8315a5b90 (patch) | |
| tree | 08557c0fe426e9c94e32b171a1ca688bd589091b | |
| parent | b264e1d19a2d83fd6fbd842eddb285bc7b77471d (diff) | |
| download | glibc-d7e1ad053b0d742f4f9c632dc0c5feb8315a5b90.tar glibc-d7e1ad053b0d742f4f9c632dc0c5feb8315a5b90.tar.gz glibc-d7e1ad053b0d742f4f9c632dc0c5feb8315a5b90.tar.bz2 glibc-d7e1ad053b0d742f4f9c632dc0c5feb8315a5b90.zip | |
(DO_MODIFY_LDT): Move from INIT_THREAD_SELF. (INIT_THREAD_SELF): Use sys_thread_area syscall instead if available. (FREE_THREAD): Avoid modify_ldt if using GDT.
| -rw-r--r-- | linuxthreads/sysdeps/i386/useldt.h | 59 |
1 files changed, 55 insertions, 4 deletions
diff --git a/linuxthreads/sysdeps/i386/useldt.h b/linuxthreads/sysdeps/i386/useldt.h index 3edcdca26c..4fd226e270 100644 --- a/linuxthreads/sysdeps/i386/useldt.h +++ b/linuxthreads/sysdeps/i386/useldt.h @@ -22,6 +22,7 @@ #ifndef __ASSEMBLER__ #include <stddef.h> /* For offsetof. */ #include <stdlib.h> /* For abort(). */ +#include <sysdep.h> /* For INLINE_SYSCALL. */ /* We don't want to include the kernel header. So duplicate the @@ -61,24 +62,74 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); __self; \ }) -/* Initialize the thread-unique value. */ -#define INIT_THREAD_SELF(descr, nr) \ -{ \ +#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 (); \ - __asm__ __volatile__ ("movw %w0, %%gs" : : "q" (nr * 8 + 7)); \ + 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 + +/* 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)); \ +} +#endif /* Free resources associated with thread descriptor. */ +#ifdef __ASSUME_SET_THREAD_AREA_SYSCALL +#define FREE_THREAD(descr, nr) do { } while (0) +#elif defined __NR_set_thread_area +#define FREE_THREAD(descr, nr) \ +{ \ + int __gs; \ + __asm__ __volatile__ ("movw %%gs, %w0" : "=q" (__gs)); \ + if (__builtin_expect (__gs & 4, 0)) \ + { \ + struct modify_ldt_ldt_s ldt_entry = \ + { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \ + __modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \ + } \ +} +#else #define FREE_THREAD(descr, nr) \ { \ struct modify_ldt_ldt_s ldt_entry = \ { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \ __modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \ } +#endif /* Read member of the thread descriptor directly. */ #define THREAD_GETMEM(descr, member) \ |