diff options
Diffstat (limited to 'libc/private/bionic_tls.h')
| -rw-r--r-- | libc/private/bionic_tls.h | 54 |
1 files changed, 12 insertions, 42 deletions
diff --git a/libc/private/bionic_tls.h b/libc/private/bionic_tls.h index 4dd66c0..dfbb142 100644 --- a/libc/private/bionic_tls.h +++ b/libc/private/bionic_tls.h @@ -79,54 +79,19 @@ enum { #define BIONIC_TLS_SLOTS 64 /* set the Thread Local Storage, must contain at least BIONIC_TLS_SLOTS pointers */ -extern void __init_tls(void** tls, void* thread_info); +extern void __init_tls(void** tls, void* thread_info); /* syscall only, do not call directly */ -extern int __set_tls(void *ptr); +extern int __set_tls(void* ptr); /* get the TLS */ -#ifdef __arm__ -/* The standard way to get the TLS is to call a kernel helper - * function (i.e. a function provided at a fixed address in a - * "magic page" mapped in all user-space address spaces ), which - * contains the most appropriate code path for the target device. - * - * However, for performance reasons, we're going to use our own - * machine code for the system's C shared library. - * - * We cannot use this optimization in the static version of the - * C library, because we don't know where the corresponding code - * is going to run. - */ -# ifdef LIBC_STATIC - -/* Use the kernel helper in static C library. */ - typedef volatile void* (__kernel_get_tls_t)(void); -# define __get_tls() (*(__kernel_get_tls_t *)0xffff0fe0)() - -# else /* !LIBC_STATIC */ -/* Use optimized code path. - * Note that HAVE_ARM_TLS_REGISTER is build-specific - * (it must match your kernel configuration) - */ -# ifdef HAVE_ARM_TLS_REGISTER - /* We can read the address directly from a coprocessor - * register, which avoids touching the data cache - * completely. - */ -# define __get_tls() \ +#if defined(__arm__) +# define __get_tls() \ ({ register unsigned int __val asm("r0"); \ asm ("mrc p15, 0, r0, c13, c0, 3" : "=r"(__val) ); \ (volatile void*)__val; }) -# else /* !HAVE_ARM_TLS_REGISTER */ - /* The kernel provides the address of the TLS at a fixed - * address of the magic page too. - */ -# define __get_tls() ( *((volatile void **) 0xffff0ff0) ) -# endif -# endif /* !LIBC_STATIC */ #elif defined(__mips__) -# define __get_tls() \ +# define __get_tls() \ ({ register unsigned int __val asm("v1"); \ asm ( \ " .set push\n" \ @@ -136,12 +101,17 @@ extern int __set_tls(void *ptr); : "=r"(__val) \ ); \ (volatile void*)__val; }) +#elif defined(__i386__) +# define __get_tls() \ + ({ register void* __val; \ + asm ("movl %%gs:0, %0" : "=r"(__val)); \ + (volatile void*) __val; }) #else -extern void* __get_tls( void ); +#error unsupported architecture #endif /* return the stack base and size, used by our malloc debugger */ -extern void* __get_stack_base(int *p_stack_size); +extern void* __get_stack_base(int* p_stack_size); __END_DECLS |