diff options
Diffstat (limited to 'nptl/pthread_mutex_init.c')
| -rw-r--r-- | nptl/pthread_mutex_init.c | 36 |
1 files changed, 21 insertions, 15 deletions
diff --git a/nptl/pthread_mutex_init.c b/nptl/pthread_mutex_init.c index 2b3468835c..9f28b8d8dc 100644 --- a/nptl/pthread_mutex_init.c +++ b/nptl/pthread_mutex_init.c @@ -18,6 +18,7 @@ #include <assert.h> #include <errno.h> +#include <stdbool.h> #include <string.h> #include <kernel-features.h> #include "pthreadP.h" @@ -31,10 +32,26 @@ static const struct pthread_mutexattr default_mutexattr = }; -#ifndef __ASSUME_FUTEX_LOCK_PI -static int tpi_supported; +static bool +prio_inherit_missing (void) +{ +#ifdef __NR_futex +# ifndef __ASSUME_FUTEX_LOCK_PI + static int tpi_supported; + if (__glibc_unlikely (tpi_supported == 0)) + { + int lock = 0; + INTERNAL_SYSCALL_DECL (err); + int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI, 0, 0); + assert (INTERNAL_SYSCALL_ERROR_P (ret, err)); + tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1; + } + return __glibc_unlikely (tpi_supported < 0); +# endif + return false; #endif - + return true; +} int __pthread_mutex_init (mutex, mutexattr) @@ -58,19 +75,8 @@ __pthread_mutex_init (mutex, mutexattr) break; case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT: -#ifndef __ASSUME_FUTEX_LOCK_PI - if (__glibc_unlikely (tpi_supported == 0)) - { - int lock = 0; - INTERNAL_SYSCALL_DECL (err); - int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI, - 0, 0); - assert (INTERNAL_SYSCALL_ERROR_P (ret, err)); - tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1; - } - if (__glibc_unlikely (tpi_supported < 0)) + if (__glibc_unlikely (prio_inherit_missing ())) return ENOTSUP; -#endif break; default: |