diff options
Diffstat (limited to 'linuxthreads/sysdeps/i386')
| -rw-r--r-- | linuxthreads/sysdeps/i386/tls.h | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/linuxthreads/sysdeps/i386/tls.h b/linuxthreads/sysdeps/i386/tls.h index 7715303d95..8bbe5f28e6 100644 --- a/linuxthreads/sysdeps/i386/tls.h +++ b/linuxthreads/sysdeps/i386/tls.h @@ -43,8 +43,17 @@ typedef struct #endif -/* We can support TLS only if the floating-stack support is available. */ -#if defined FLOATING_STACKS && defined HAVE_TLS_SUPPORT +/* 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) /* Signal that TLS support is available. */ # define USE_TLS 1 @@ -96,8 +105,21 @@ typedef struct # define TLS_LOAD_EBX # endif +# if __ASSUME_LDT_WORKS > 0 +# define TLS_DO_MODIFY_LDT_KERNEL_CHECK /* Nothing to do. */ +# 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); +# 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 */, \ 1, 0, 0, 1, 0, 1, 0 }; \ @@ -177,7 +199,7 @@ typedef struct ({ struct _pthread_descr_struct *__descr; \ THREAD_GETMEM (__descr, p_header.data.dtvp); }) -# endif /* FLOATING_STACKS && HAVE_TLS_SUPPORT */ +# endif /* HAVE_TLS_SUPPORT && (FLOATING_STACKS || !IS_IN_libpthread) */ #endif /* __ASSEMBLER__ */ #endif /* tls.h */ |