int __pthread_setaffinity_new (pthread_t th, size_t cpusetsize, const cpu_set_t *cpuset) { const struct pthread *pd = (const struct pthread *) th; INTERNAL_SYSCALL_DECL (err); int res; if (__builtin_expect (__kernel_cpumask_size == 0, 0)) { res = __determine_cpumask_size (pd->tid); if (res != 0) return res; } /* We now know the size of the kernel cpumask_t. Make sure the user does not request to set a bit beyond that. */ for (size_t cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt) if (((char *) cpuset)[cnt] != '\0') /* Found a nonzero byte. This means the user request cannot be fulfilled. */ return EINVAL; res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, cpusetsize, cpuset); #ifdef RESET_VGETCPU_CACHE if (!INTERNAL_SYSCALL_ERROR_P (res, err)) RESET_VGETCPU_CACHE (); #endif return (INTERNAL_SYSCALL_ERROR_P (res, err) ? INTERNAL_SYSCALL_ERRNO (res, err) : 0); }
/* Get information about the file NAME in BUF. */ int __fxstatat (int vers, int fd, const char *file, struct stat *st, int flag) { int result; INTERNAL_SYSCALL_DECL (err); #ifdef STAT_IS_KERNEL_STAT # define kst (*st) #else struct kernel_stat kst; #endif result = INTERNAL_SYSCALL (newfstatat, err, 4, fd, file, &kst, flag); if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1)) { #ifdef STAT_IS_KERNEL_STAT return 0; #else return __xstat_conv (vers, &kst, st); #endif } else return INLINE_SYSCALL_ERROR_RETURN_VALUE (INTERNAL_SYSCALL_ERRNO (result, err)); }
pthread_mutex_timedlock ( pthread_mutex_t *mutex, const struct timespec *abstime) { int oldval; pid_t id = THREAD_GETMEM (THREAD_SELF, tid); int result = 0; /* We must not check ABSTIME here. If the thread does not block abstime must not be checked for a valid value. */ switch (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex), PTHREAD_MUTEX_TIMED_NP)) { /* Recursive mutex. */ case PTHREAD_MUTEX_RECURSIVE_NP: /* Check whether we already hold the mutex. */ if (mutex->__data.__owner == id) { /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; goto out; } /* We have to get the mutex. */ result = lll_timedlock (mutex->__data.__lock, abstime, PTHREAD_MUTEX_PSHARED (mutex)); if (result != 0) goto out; /* Only locked once so far. */ mutex->__data.__count = 1; break; /* Error checking mutex. */ case PTHREAD_MUTEX_ERRORCHECK_NP: /* Check whether we already hold the mutex. */ if (__builtin_expect (mutex->__data.__owner == id, 0)) return EDEADLK; /* FALLTHROUGH */ case PTHREAD_MUTEX_TIMED_NP: simple: /* Normal mutex. */ result = lll_timedlock (mutex->__data.__lock, abstime, PTHREAD_MUTEX_PSHARED (mutex)); break; case PTHREAD_MUTEX_ADAPTIVE_NP: if (! __is_smp) goto simple; if (lll_trylock (mutex->__data.__lock) != 0) { int cnt = 0; int max_cnt = MIN (MAX_ADAPTIVE_COUNT, mutex->__data.__spins * 2 + 10); do { if (cnt++ >= max_cnt) { result = lll_timedlock (mutex->__data.__lock, abstime, PTHREAD_MUTEX_PSHARED (mutex)); break; } #ifdef BUSY_WAIT_NOP BUSY_WAIT_NOP; #endif } while (lll_trylock (mutex->__data.__lock) != 0); mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8; } break; case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, &mutex->__data.__list.__next); oldval = mutex->__data.__lock; do { again: if ((oldval & FUTEX_OWNER_DIED) != 0) { /* The previous owner died. Try locking the mutex. */ int newval = id | (oldval & FUTEX_WAITERS); newval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, newval, oldval); if (newval != oldval) { oldval = newval; goto again; } /* We got the mutex. */ mutex->__data.__count = 1; /* But it is inconsistent unless marked otherwise. */ mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be incremented which is not correct because the old owner has to be discounted. */ return EOWNERDEAD; } /* Check whether we already hold the mutex. */ if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { int kind = PTHREAD_MUTEX_TYPE (mutex); if (kind == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return EDEADLK; } if (kind == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } result = lll_robust_timedlock (mutex->__data.__lock, abstime, id, PTHREAD_ROBUST_MUTEX_PSHARED (mutex)); if (__builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) { /* This mutex is now not recoverable. */ mutex->__data.__count = 0; lll_unlock (mutex->__data.__lock, PTHREAD_ROBUST_MUTEX_PSHARED (mutex)); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } if (result == ETIMEDOUT || result == EINVAL) goto out; oldval = result; } while ((oldval & FUTEX_OWNER_DIED) != 0); mutex->__data.__count = 1; ENQUEUE_MUTEX (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; case PTHREAD_MUTEX_PI_RECURSIVE_NP: case PTHREAD_MUTEX_PI_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_NORMAL_NP: case PTHREAD_MUTEX_PI_ADAPTIVE_NP: case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP: case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP: { int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; int robust = mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP; if (robust) /* Note: robust PI futexes are signaled by setting bit 0. */ THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, (void *) (((uintptr_t) &mutex->__data.__list.__next) | 1)); oldval = mutex->__data.__lock; /* Check whether we already hold the mutex. */ if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return EDEADLK; } if (kind == PTHREAD_MUTEX_RECURSIVE_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, id, 0); if (oldval != 0) { /* The mutex is locked. The kernel will now take care of everything. The timeout value must be a relative value. Convert it. */ int private = (robust ? PTHREAD_ROBUST_MUTEX_PSHARED (mutex) : PTHREAD_MUTEX_PSHARED (mutex)); INTERNAL_SYSCALL_DECL (__err); int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, __lll_private_flag (FUTEX_LOCK_PI, private), 1, abstime); if (INTERNAL_SYSCALL_ERROR_P (e, __err)) { if (INTERNAL_SYSCALL_ERRNO (e, __err) == ETIMEDOUT) return ETIMEDOUT; if (INTERNAL_SYSCALL_ERRNO (e, __err) == ESRCH || INTERNAL_SYSCALL_ERRNO (e, __err) == EDEADLK) { assert (INTERNAL_SYSCALL_ERRNO (e, __err) != EDEADLK || (kind != PTHREAD_MUTEX_ERRORCHECK_NP && kind != PTHREAD_MUTEX_RECURSIVE_NP)); /* ESRCH can happen only for non-robust PI mutexes where the owner of the lock died. */ assert (INTERNAL_SYSCALL_ERRNO (e, __err) != ESRCH || !robust); /* Delay the thread until the timeout is reached. Then return ETIMEDOUT. */ struct timespec reltime; struct timespec now; INTERNAL_SYSCALL (clock_gettime, __err, 2, CLOCK_REALTIME, &now); reltime.tv_sec = abstime->tv_sec - now.tv_sec; reltime.tv_nsec = abstime->tv_nsec - now.tv_nsec; if (reltime.tv_nsec < 0) { reltime.tv_nsec += 1000000000; --reltime.tv_sec; } if (reltime.tv_sec >= 0) while (nanosleep_not_cancel (&reltime, &reltime) != 0) continue; return ETIMEDOUT; } return INTERNAL_SYSCALL_ERRNO (e, __err); } oldval = mutex->__data.__lock; assert (robust || (oldval & FUTEX_OWNER_DIED) == 0); } if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0)) { atomic_and (&mutex->__data.__lock, ~FUTEX_OWNER_DIED); /* We got the mutex. */ mutex->__data.__count = 1; /* But it is inconsistent unless marked otherwise. */ mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX_PI (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be incremented which is not correct because the old owner has to be discounted. */ return EOWNERDEAD; } if (robust && __builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) { /* This mutex is now not recoverable. */ mutex->__data.__count = 0; INTERNAL_SYSCALL_DECL (__err); INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, __lll_private_flag (FUTEX_UNLOCK_PI, PTHREAD_ROBUST_MUTEX_PSHARED (mutex)), 0, 0); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } mutex->__data.__count = 1; if (robust) { ENQUEUE_MUTEX_PI (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); } } break; case PTHREAD_MUTEX_PP_RECURSIVE_NP: case PTHREAD_MUTEX_PP_ERRORCHECK_NP: case PTHREAD_MUTEX_PP_NORMAL_NP: case PTHREAD_MUTEX_PP_ADAPTIVE_NP: { int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; oldval = mutex->__data.__lock; /* Check whether we already hold the mutex. */ if (mutex->__data.__owner == id) { if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) return EDEADLK; if (kind == PTHREAD_MUTEX_RECURSIVE_NP) { /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } int oldprio = -1, ceilval; do { int ceiling = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT; if (__pthread_current_priority () > ceiling) { result = EINVAL; failpp: if (oldprio != -1) __pthread_tpp_change_priority (oldprio, -1); return result; } result = __pthread_tpp_change_priority (oldprio, ceiling); if (result) return result; ceilval = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT; oldprio = ceiling; oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, ceilval | 1, ceilval); if (oldval == ceilval) break; do { oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, ceilval | 2, ceilval | 1); if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval) break; if (oldval != ceilval) { /* Reject invalid timeouts. */ if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) { result = EINVAL; goto failpp; } struct timeval tv; struct timespec rt; /* Get the current time. */ (void) gettimeofday (&tv, NULL); /* Compute relative timeout. */ rt.tv_sec = abstime->tv_sec - tv.tv_sec; rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000; if (rt.tv_nsec < 0) { rt.tv_nsec += 1000000000; --rt.tv_sec; } /* Already timed out? */ if (rt.tv_sec < 0) { result = ETIMEDOUT; goto failpp; } lll_futex_timed_wait (&mutex->__data.__lock, ceilval | 2, &rt, PTHREAD_MUTEX_PSHARED (mutex)); } } while (atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, ceilval | 2, ceilval) != ceilval); } while ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval); assert (mutex->__data.__owner == 0); mutex->__data.__count = 1; } break; default: /* Correct code cannot set any other type. */ return EINVAL; }
/* Get information about the file NAME relative to FD in ST. */ int __fxstatat (int vers, int fd, const char *file, struct stat *st, int flag) { if (vers != _STAT_VER_KERNEL && vers != _STAT_VER_LINUX) { __set_errno (EINVAL); return -1; } int res; #ifdef __NR_newfstatat # ifndef __ASSUME_ATFCTS if (__have_atfcts >= 0) # endif { res = INLINE_SYSCALL (newfstatat, 4, fd, file, st, flag); # ifndef __ASSUME_ATFCTS if (res == -1 && errno == ENOSYS) __have_atfcts = -1; else # endif return res; } #endif #ifndef __ASSUME_ATFCTS if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); if (__builtin_expect (filelen == 0, 0)) { __set_errno (ENOENT); return -1; } static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } INTERNAL_SYSCALL_DECL (err); if (flag & AT_SYMLINK_NOFOLLOW) res = INTERNAL_SYSCALL (lstat, err, 2, file, CHECK_1 (st)); else res = INTERNAL_SYSCALL (stat, err, 2, file, CHECK_1 (st)); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) { __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (res, err), fd, buf); res = -1; } return res; #endif }
/* Get information about the file NAME relative to FD in ST. */ int __fxstatat (int vers, int fd, const char *file, struct stat *st, int flag) { int result; INTERNAL_SYSCALL_DECL (err); struct stat64 st64; #ifdef __NR_fstatat64 # ifndef __ASSUME_ATFCTS if (__have_atfcts >= 0) # endif { result = INTERNAL_SYSCALL (fstatat64, err, 4, fd, file, &st64, flag); # ifndef __ASSUME_ATFCTS if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1) && INTERNAL_SYSCALL_ERRNO (result, err) == ENOSYS) __have_atfcts = -1; else # endif if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat32_conv (vers, &st64, st); else { __set_errno (INTERNAL_SYSCALL_ERRNO (result, err)); return -1; } } #endif #ifndef __ASSUME_ATFCTS if (__builtin_expect (flag & ~AT_SYMLINK_NOFOLLOW, 0)) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } # if __ASSUME_STAT64_SYSCALL == 0 struct kernel_stat kst; # endif if (vers == _STAT_VER_KERNEL) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, CHECK_STRING (file), CHECK_1 ((struct kernel_stat *) st)); else result = INTERNAL_SYSCALL (stat, err, 2, CHECK_STRING (file), CHECK_1 ((struct kernel_stat *) st)); goto out; } # if __ASSUME_STAT64_SYSCALL > 0 if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat64, err, 2, CHECK_STRING (file), __ptrvalue (&st64)); else result = INTERNAL_SYSCALL (stat64, err, 2, CHECK_STRING (file), __ptrvalue (&st64)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat32_conv (vers, &st64, st); # else # if defined __NR_stat64 /* To support 32 bit UIDs, we have to use stat64. The normal stat call only returns 16 bit UIDs. */ if (! __have_no_stat64) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat64, err, 2, CHECK_STRING (file), __ptrvalue (&st64)); else result = INTERNAL_SYSCALL (stat64, err, 2, CHECK_STRING (file), __ptrvalue (&st64)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) result = __xstat32_conv (vers, &st64, st); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1) || INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS) goto out; __have_no_stat64 = 1; } # endif if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, CHECK_STRING (file), __ptrvalue (&kst)); else result = INTERNAL_SYSCALL (stat, err, 2, CHECK_STRING (file), __ptrvalue (&kst)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat_conv (vers, &kst, st); # endif /* __ASSUME_STAT64_SYSCALL */ out: if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) { __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); result = -1; } return result; #endif }
int pthread_cancel (pthread_t th) { volatile struct pthread *pd = (volatile struct pthread *) th; /* Make sure the descriptor is valid. */ if (INVALID_TD_P (pd)) /* Not a valid thread handle. */ return ESRCH; #ifdef SHARED pthread_cancel_init (); #endif int result = 0; int oldval; int newval; do { again: oldval = pd->cancelhandling; newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK; /* Avoid doing unnecessary work. The atomic operation can potentially be expensive if the bug has to be locked and remote cache lines have to be invalidated. */ if (oldval == newval) break; /* If the cancellation is handled asynchronously just send a signal. We avoid this if possible since it's more expensive. */ if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval)) { /* Mark the cancellation as "in progress". */ if (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling, oldval | CANCELING_BITMASK, oldval)) goto again; #ifdef SIGCANCEL /* The cancellation handler will take care of marking the thread as canceled. */ pid_t pid = getpid (); INTERNAL_SYSCALL_DECL (err); int val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, pd->tid, SIGCANCEL); if (INTERNAL_SYSCALL_ERROR_P (val, err)) result = INTERNAL_SYSCALL_ERRNO (val, err); #else /* It should be impossible to get here at all, since pthread_setcanceltype should never have allowed PTHREAD_CANCEL_ASYNCHRONOUS to be set. */ abort (); #endif break; } /* A single-threaded process should be able to kill itself, since there is nothing in the POSIX specification that says that it cannot. So we set multiple_threads to true so that cancellation points get executed. */ THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1); #ifndef TLS_MULTIPLE_THREADS_IN_TCB __pthread_multiple_threads = *__libc_multiple_threads_ptr = 1; #endif } /* Mark the thread as canceled. This has to be done atomically since other bits could be modified as well. */ while (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling, newval, oldval)); return result; }
int fchownat (int fd, const char *file, uid_t owner, gid_t group, int flag) { if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } int result; INTERNAL_SYSCALL_DECL (err); #if __ASSUME_LCHOWN_SYSCALL if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown, err, 3, file, owner, group); else result = INTERNAL_SYSCALL (chown, err, 3, file, owner, group); #else char link[PATH_MAX + 2]; char path[2 * PATH_MAX + 4]; int loopct; size_t filelen; static int libc_old_chown = 0 /* -1=old linux, 1=new linux, 0=unknown */; if (libc_old_chown == 1) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown, err, 3, __ptrvalue (file), owner, group); else result = INTERNAL_SYSCALL (chown, err, 3, __ptrvalue (file), owner, group); goto out; } # ifdef __NR_lchown if (flag & AT_SYMLINK_NOFOLLOW) { result = INTERNAL_SYSCALL (lchown, err, 3, __ptrvalue (file), owner, group); goto out; } if (libc_old_chown == 0) { result = INTERNAL_SYSCALL (chown, err, 3, __ptrvalue (file), owner, group); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return result; if (INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS) { libc_old_chown = 1; goto fail; } libc_old_chown = -1; } # else if (flag & AT_SYMLINK_NOFOLLOW) { result = INTERNAL_SYSCALL (chown, err, 3, __ptrvalue (file), owner, group); goto out; } # endif result = __readlink (file, link, PATH_MAX + 1); if (result == -1) { # ifdef __NR_lchown result = INTERNAL_SYSCALL (lchown, err, 3, __ptrvalue (file), owner, group); # else result = INTERNAL_SYSCALL (chown, err, 3, __ptrvalue (file), owner, group); # endif goto out; } filelen = strlen (file) + 1; if (filelen > sizeof (path)) { errno = ENAMETOOLONG; return -1; } memcpy (path, file, filelen); /* 'The system has an arbitrary limit...' In practise, we'll hit ENAMETOOLONG before this, usually. */ for (loopct = 0; loopct < 128; ++loopct) { size_t linklen; if (result >= PATH_MAX + 1) { errno = ENAMETOOLONG; return -1; } link[result] = 0; /* Null-terminate string, just-in-case. */ linklen = strlen (link) + 1; if (link[0] == '/') memcpy (path, link, linklen); else { filelen = strlen (path); while (filelen > 1 && path[filelen - 1] == '/') --filelen; while (filelen > 0 && path[filelen - 1] != '/') --filelen; if (filelen + linklen > sizeof (path)) { errno = ENAMETOOLONG; return -1; } memcpy (path + filelen, link, linklen); } result = __readlink (path, link, PATH_MAX + 1); if (result == -1) { # ifdef __NR_lchown result = INTERNAL_SYSCALL (lchown, err, 3, path, owner, group); # else result = INTERNAL_SYSCALL (chown, err, 3, path, owner, group); # endif goto out; } } __set_errno (ELOOP); return -1; out: #endif if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) { #if !__ASSUME_LCHOWN_SYSCALL fail: #endif __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); result = -1; } return result; }
/* Get information about the file NAME in BUF. */ int __fxstatat (int vers, int fd, const char *file, struct stat *st, int flag) { int result; INTERNAL_SYSCALL_DECL (err); #ifdef STAT_IS_KERNEL_STAT # define kst (*st) #else struct kernel_stat kst; #endif #ifdef __NR_newfstatat # ifndef __ASSUME_ATFCTS if (__have_atfcts >= 0) # endif { result = INTERNAL_SYSCALL (newfstatat, err, 4, fd, file, &kst, flag); # ifndef __ASSUME_ATFCTS if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1) && INTERNAL_SYSCALL_ERRNO (result, err) == ENOSYS) __have_atfcts = -1; else # endif if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1)) { #ifdef STAT_IS_KERNEL_STAT return 0; #else return __xstat_conv (vers, &kst, st); #endif } else { __set_errno (INTERNAL_SYSCALL_ERRNO (result, err)); return -1; } } #endif if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); if (__builtin_expect (filelen == 0, 0)) { __set_errno (ENOENT); return -1; } static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } if (vers == _STAT_VER_KERNEL) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, file, (struct kernel_stat *) st); else result = INTERNAL_SYSCALL (stat, err, 2, file, (struct kernel_stat *) st); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return result; } #ifdef STAT_IS_KERNEL_STAT else { __set_errno (EINVAL); return -1; } #else if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, file, &kst); else result = INTERNAL_SYSCALL (stat, err, 2, file, &kst); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat_conv (vers, &kst, st); #endif __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); return -1; }
void __pthread_initialize_minimal_internal (void) { #ifndef SHARED /* Unlike in the dynamically linked case the dynamic linker has not taken care of initializing the TLS data structures. */ __libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN); /* We must prevent gcc from being clever and move any of the following code ahead of the __libc_setup_tls call. This function will initialize the thread register which is subsequently used. */ __asm __volatile (""); #endif /* Minimal initialization of the thread descriptor. */ struct pthread *pd = THREAD_SELF; __pthread_initialize_pids (pd); THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]); THREAD_SETMEM (pd, user_stack, true); if (LLL_LOCK_INITIALIZER != 0) THREAD_SETMEM (pd, lock, LLL_LOCK_INITIALIZER); #if HP_TIMING_AVAIL THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset)); #endif /* Initialize the robust mutex data. */ { #ifdef __PTHREAD_MUTEX_HAVE_PREV pd->robust_prev = &pd->robust_head; #endif pd->robust_head.list = &pd->robust_head; #ifdef __NR_set_robust_list pd->robust_head.futex_offset = (offsetof (pthread_mutex_t, __data.__lock) - offsetof (pthread_mutex_t, __data.__list.__next)); INTERNAL_SYSCALL_DECL (err); int res = INTERNAL_SYSCALL (set_robust_list, err, 2, &pd->robust_head, sizeof (struct robust_list_head)); if (INTERNAL_SYSCALL_ERROR_P (res, err)) #endif set_robust_list_not_avail (); } #ifdef __NR_futex # ifndef __ASSUME_PRIVATE_FUTEX /* Private futexes are always used (at least internally) so that doing the test once this early is beneficial. */ { int word = 0; INTERNAL_SYSCALL_DECL (err); word = INTERNAL_SYSCALL (futex, err, 3, &word, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1); if (!INTERNAL_SYSCALL_ERROR_P (word, err)) THREAD_SETMEM (pd, header.private_futex, FUTEX_PRIVATE_FLAG); } /* Private futexes have been introduced earlier than the FUTEX_CLOCK_REALTIME flag. We don't have to run the test if we know the former are not supported. This also means we know the kernel will return ENOSYS for unknown operations. */ if (THREAD_GETMEM (pd, header.private_futex) != 0) # endif # ifndef __ASSUME_FUTEX_CLOCK_REALTIME { int word = 0; /* NB: the syscall actually takes six parameters. The last is the bit mask. But since we will not actually wait at all the value is irrelevant. Given that passing six parameters is difficult on some architectures we just pass whatever random value the calling convention calls for to the kernel. It causes no harm. */ INTERNAL_SYSCALL_DECL (err); word = INTERNAL_SYSCALL (futex, err, 5, &word, FUTEX_WAIT_BITSET | FUTEX_CLOCK_REALTIME | FUTEX_PRIVATE_FLAG, 1, NULL, 0); assert (INTERNAL_SYSCALL_ERROR_P (word, err)); if (INTERNAL_SYSCALL_ERRNO (word, err) != ENOSYS) __set_futex_clock_realtime (); } # endif #endif /* Set initial thread's stack block from 0 up to __libc_stack_end. It will be bigger than it actually is, but for unwind.c/pt-longjmp.c purposes this is good enough. */ THREAD_SETMEM (pd, stackblock_size, (size_t) __libc_stack_end); /* Initialize the list of all running threads with the main thread. */ INIT_LIST_HEAD (&__stack_user); list_add (&pd->list, &__stack_user); /* Before initializing __stack_user, the debugger could not find us and had to set __nptl_initial_report_events. Propagate its setting. */ THREAD_SETMEM (pd, report_events, __nptl_initial_report_events); #if defined SIGCANCEL || defined SIGSETXID struct sigaction sa; __sigemptyset (&sa.sa_mask); # ifdef SIGCANCEL /* Install the cancellation signal handler. If for some reason we cannot install the handler we do not abort. Maybe we should, but it is only asynchronous cancellation which is affected. */ sa.sa_sigaction = sigcancel_handler; sa.sa_flags = SA_SIGINFO; (void) __libc_sigaction (SIGCANCEL, &sa, NULL); # endif # ifdef SIGSETXID /* Install the handle to change the threads' uid/gid. */ sa.sa_sigaction = sighandler_setxid; sa.sa_flags = SA_SIGINFO | SA_RESTART; (void) __libc_sigaction (SIGSETXID, &sa, NULL); # endif /* The parent process might have left the signals blocked. Just in case, unblock it. We reuse the signal mask in the sigaction structure. It is already cleared. */ # ifdef SIGCANCEL __sigaddset (&sa.sa_mask, SIGCANCEL); # endif # ifdef SIGSETXID __sigaddset (&sa.sa_mask, SIGSETXID); # endif { INTERNAL_SYSCALL_DECL (err); (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask, NULL, _NSIG / 8); } #endif /* Get the size of the static and alignment requirements for the TLS block. */ size_t static_tls_align; _dl_get_tls_static_info (&__static_tls_size, &static_tls_align); /* Make sure the size takes all the alignments into account. */ if (STACK_ALIGN > static_tls_align) static_tls_align = STACK_ALIGN; __static_tls_align_m1 = static_tls_align - 1; __static_tls_size = roundup (__static_tls_size, static_tls_align); /* Determine the default allowed stack size. This is the size used in case the user does not specify one. */ struct rlimit limit; if (__getrlimit (RLIMIT_STACK, &limit) != 0 || limit.rlim_cur == RLIM_INFINITY) /* The system limit is not usable. Use an architecture-specific default. */ limit.rlim_cur = ARCH_STACK_DEFAULT_SIZE; else if (limit.rlim_cur < PTHREAD_STACK_MIN) /* The system limit is unusably small. Use the minimal size acceptable. */ limit.rlim_cur = PTHREAD_STACK_MIN; /* Make sure it meets the minimum size that allocate_stack (allocatestack.c) will demand, which depends on the page size. */ const uintptr_t pagesz = GLRO(dl_pagesize); const size_t minstack = pagesz + __static_tls_size + MINIMAL_REST_STACK; if (limit.rlim_cur < minstack) limit.rlim_cur = minstack; /* Round the resource limit up to page size. */ limit.rlim_cur = ALIGN_UP (limit.rlim_cur, pagesz); lll_lock (__default_pthread_attr_lock, LLL_PRIVATE); __default_pthread_attr.stacksize = limit.rlim_cur; __default_pthread_attr.guardsize = GLRO (dl_pagesize); lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE); #ifdef SHARED /* Transfer the old value from the dynamic linker's internal location. */ *__libc_dl_error_tsd () = *(*GL(dl_error_catch_tsd)) (); GL(dl_error_catch_tsd) = &__libc_dl_error_tsd; /* Make __rtld_lock_{,un}lock_recursive use pthread_mutex_{,un}lock, keep the lock count from the ld.so implementation. */ GL(dl_rtld_lock_recursive) = (void *) __pthread_mutex_lock; GL(dl_rtld_unlock_recursive) = (void *) __pthread_mutex_unlock; unsigned int rtld_lock_count = GL(dl_load_lock).mutex.__data.__count; GL(dl_load_lock).mutex.__data.__count = 0; while (rtld_lock_count-- > 0) __pthread_mutex_lock (&GL(dl_load_lock).mutex); GL(dl_make_stack_executable_hook) = &__make_stacks_executable; #endif GL(dl_init_static_tls) = &__pthread_init_static_tls; GL(dl_wait_lookup_done) = &__wait_lookup_done; /* Register the fork generation counter with the libc. */ #ifndef TLS_MULTIPLE_THREADS_IN_TCB __libc_multiple_threads_ptr = #endif __libc_pthread_init (&__fork_generation, __reclaim_stacks, ptr_pthread_functions); /* Determine whether the machine is SMP or not. */ __is_smp = is_smp_system (); }
int timer_create (clockid_t clock_id, struct sigevent *evp, timer_t *timerid) { #undef timer_create { clockid_t syscall_clockid = (clock_id == CLOCK_PROCESS_CPUTIME_ID ? MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED) : clock_id == CLOCK_THREAD_CPUTIME_ID ? MAKE_THREAD_CPUCLOCK (0, CPUCLOCK_SCHED) : clock_id); /* If the user wants notification via a thread we need to handle this special. */ if (evp == NULL || __builtin_expect (evp->sigev_notify != SIGEV_THREAD, 1)) { struct sigevent local_evp; /* We avoid allocating too much memory by basically using struct timer as a derived class with the first two elements being in the superclass. We only need these two elements here. */ struct timer *newp = (struct timer *) malloc (offsetof (struct timer, thrfunc)); if (newp == NULL) /* No more memory. */ return -1; if (evp == NULL) { /* The kernel has to pass up the timer ID which is a userlevel object. Therefore we cannot leave it up to the kernel to determine it. */ local_evp.sigev_notify = SIGEV_SIGNAL; local_evp.sigev_signo = SIGALRM; local_evp.sigev_value.sival_ptr = newp; evp = &local_evp; } kernel_timer_t ktimerid; int retval = INLINE_SYSCALL (timer_create, 3, syscall_clockid, evp, &ktimerid); if (retval != -1) { newp->sigev_notify = (evp != NULL ? evp->sigev_notify : SIGEV_SIGNAL); newp->ktimerid = ktimerid; *timerid = (timer_t) newp; } else { /* Cannot allocate the timer, fail. */ free (newp); retval = -1; } return retval; } else { /* Create the helper thread. */ pthread_once (&__helper_once, __start_helper_thread); if (__helper_tid == 0) { /* No resources to start the helper thread. */ __set_errno (EAGAIN); return -1; } struct timer *newp; newp = (struct timer *) malloc (sizeof (struct timer)); if (newp == NULL) return -1; /* Copy the thread parameters the user provided. */ newp->sival = evp->sigev_value; newp->thrfunc = evp->sigev_notify_function; newp->sigev_notify = SIGEV_THREAD; /* We cannot simply copy the thread attributes since the implementation might keep internal information for each instance. */ (void) pthread_attr_init (&newp->attr); if (evp->sigev_notify_attributes != NULL) { struct pthread_attr *nattr; struct pthread_attr *oattr; nattr = (struct pthread_attr *) &newp->attr; oattr = (struct pthread_attr *) evp->sigev_notify_attributes; nattr->schedparam = oattr->schedparam; nattr->schedpolicy = oattr->schedpolicy; nattr->flags = oattr->flags; nattr->guardsize = oattr->guardsize; nattr->stackaddr = oattr->stackaddr; nattr->stacksize = oattr->stacksize; } /* In any case set the detach flag. */ (void) pthread_attr_setdetachstate (&newp->attr, PTHREAD_CREATE_DETACHED); /* Create the event structure for the kernel timer. */ struct sigevent sev = { .sigev_value.sival_ptr = newp, .sigev_signo = SIGTIMER, .sigev_notify = SIGEV_SIGNAL | SIGEV_THREAD_ID, ._sigev_un = { ._pad = { [0] = __helper_tid } } }; /* Create the timer. */ INTERNAL_SYSCALL_DECL (err); int res; res = INTERNAL_SYSCALL (timer_create, err, 3, syscall_clockid, &sev, &newp->ktimerid); if (! INTERNAL_SYSCALL_ERROR_P (res, err)) { /* Add to the queue of active timers with thread delivery. */ pthread_mutex_lock (&__active_timer_sigev_thread_lock); newp->next = __active_timer_sigev_thread; __active_timer_sigev_thread = newp; pthread_mutex_unlock (&__active_timer_sigev_thread_lock); *timerid = (timer_t) newp; return 0; } /* Free the resources. */ free (newp); __set_errno (INTERNAL_SYSCALL_ERRNO (res, err)); return -1; } }
int clock_getcpuclockid (pid_t pid, clockid_t *clock_id) { #ifdef __NR_clock_getres /* The clockid_t value is a simple computation from the PID. But we do a clock_getres call to validate it. */ const clockid_t pidclock = MAKE_PROCESS_CPUCLOCK (pid, CPUCLOCK_SCHED); # if !(__ASSUME_POSIX_CPU_TIMERS > 0) extern int __libc_missing_posix_cpu_timers attribute_hidden; # if !(__ASSUME_POSIX_TIMERS > 0) extern int __libc_missing_posix_timers attribute_hidden; if (__libc_missing_posix_timers && !__libc_missing_posix_cpu_timers) __libc_missing_posix_cpu_timers = 1; # endif if (!__libc_missing_posix_cpu_timers) # endif { INTERNAL_SYSCALL_DECL (err); int r = INTERNAL_SYSCALL (clock_getres, err, 2, pidclock, NULL); if (!INTERNAL_SYSCALL_ERROR_P (r, err)) { *clock_id = pidclock; return 0; } # if !(__ASSUME_POSIX_TIMERS > 0) if (INTERNAL_SYSCALL_ERRNO (r, err) == ENOSYS) { /* The kernel doesn't support these calls at all. */ __libc_missing_posix_timers = 1; __libc_missing_posix_cpu_timers = 1; } else # endif if (INTERNAL_SYSCALL_ERRNO (r, err) == EINVAL) { # if !(__ASSUME_POSIX_CPU_TIMERS > 0) if (pidclock == MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED) || INTERNAL_SYSCALL_ERROR_P (INTERNAL_SYSCALL (clock_getres, err, 2, MAKE_PROCESS_CPUCLOCK (0, CPUCLOCK_SCHED), NULL), err)) /* The kernel doesn't support these clocks at all. */ __libc_missing_posix_cpu_timers = 1; else # endif /* The clock_getres system call checked the PID for us. */ return ESRCH; } else return INTERNAL_SYSCALL_ERRNO (r, err); } #endif /* We don't allow any process ID but our own. */ if (pid != 0 && pid != getpid ()) return EPERM; #ifdef CLOCK_PROCESS_CPUTIME_ID if (HAS_CPUCLOCK) { /* Store the number. */ *clock_id = CLOCK_PROCESS_CPUTIME_ID; return 0; } #endif /* We don't have a timer for that. */ return ENOENT; }
static int __pthread_mutex_lock_full (pthread_mutex_t *mutex) { int oldval; pid_t id = THREAD_GETMEM (THREAD_SELF, tid); switch (PTHREAD_MUTEX_TYPE (mutex)) { case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, &mutex->__data.__list.__next); oldval = mutex->__data.__lock; do { again: if ((oldval & FUTEX_OWNER_DIED) != 0) { /* The previous owner died. Try locking the mutex. */ int newval = id; #ifdef NO_INCR newval |= FUTEX_WAITERS; #else newval |= (oldval & FUTEX_WAITERS); #endif newval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, newval, oldval); if (newval != oldval) { oldval = newval; goto again; } /* We got the mutex. */ mutex->__data.__count = 1; /* But it is inconsistent unless marked otherwise. */ mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be incremented which is not correct because the old owner has to be discounted. If we are not supposed to increment __nusers we actually have to decrement it here. */ #ifdef NO_INCR --mutex->__data.__nusers; #endif return EOWNERDEAD; } /* Check whether we already hold the mutex. */ if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { int kind = PTHREAD_MUTEX_TYPE (mutex); if (kind == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return EDEADLK; } if (kind == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } oldval = LLL_ROBUST_MUTEX_LOCK (mutex, id); if (__builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) { /* This mutex is now not recoverable. */ mutex->__data.__count = 0; lll_unlock (mutex->__data.__lock, PTHREAD_ROBUST_MUTEX_PSHARED (mutex)); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } } while ((oldval & FUTEX_OWNER_DIED) != 0); mutex->__data.__count = 1; ENQUEUE_MUTEX (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; case PTHREAD_MUTEX_PI_RECURSIVE_NP: case PTHREAD_MUTEX_PI_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_NORMAL_NP: case PTHREAD_MUTEX_PI_ADAPTIVE_NP: case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP: case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP: { int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; int robust = mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP; if (robust) /* Note: robust PI futexes are signaled by setting bit 0. */ THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, (void *) (((uintptr_t) &mutex->__data.__list.__next) | 1)); oldval = mutex->__data.__lock; /* Check whether we already hold the mutex. */ if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) { if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return EDEADLK; } if (kind == PTHREAD_MUTEX_RECURSIVE_NP) { THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } int newval = id; #ifdef NO_INCR newval |= FUTEX_WAITERS; #endif oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, newval, 0); if (oldval != 0) { /* The mutex is locked. The kernel will now take care of everything. */ int private = (robust ? PTHREAD_ROBUST_MUTEX_PSHARED (mutex) : PTHREAD_MUTEX_PSHARED (mutex)); INTERNAL_SYSCALL_DECL (__err); int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, __lll_private_flag (FUTEX_LOCK_PI, private), 1, 0); if (INTERNAL_SYSCALL_ERROR_P (e, __err) && (INTERNAL_SYSCALL_ERRNO (e, __err) == ESRCH || INTERNAL_SYSCALL_ERRNO (e, __err) == EDEADLK)) { assert (INTERNAL_SYSCALL_ERRNO (e, __err) != EDEADLK || (kind != PTHREAD_MUTEX_ERRORCHECK_NP && kind != PTHREAD_MUTEX_RECURSIVE_NP)); /* ESRCH can happen only for non-robust PI mutexes where the owner of the lock died. */ assert (INTERNAL_SYSCALL_ERRNO (e, __err) != ESRCH || !robust); /* Delay the thread indefinitely. */ while (1) pause_not_cancel (); } oldval = mutex->__data.__lock; assert (robust || (oldval & FUTEX_OWNER_DIED) == 0); } if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0)) { atomic_and (&mutex->__data.__lock, ~FUTEX_OWNER_DIED); /* We got the mutex. */ mutex->__data.__count = 1; /* But it is inconsistent unless marked otherwise. */ mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; ENQUEUE_MUTEX_PI (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be incremented which is not correct because the old owner has to be discounted. If we are not supposed to increment __nusers we actually have to decrement it here. */ #ifdef NO_INCR --mutex->__data.__nusers; #endif return EOWNERDEAD; } if (robust && __builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) { /* This mutex is now not recoverable. */ mutex->__data.__count = 0; INTERNAL_SYSCALL_DECL (__err); INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, __lll_private_flag (FUTEX_UNLOCK_PI, PTHREAD_ROBUST_MUTEX_PSHARED (mutex)), 0, 0); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); return ENOTRECOVERABLE; } mutex->__data.__count = 1; if (robust) { ENQUEUE_MUTEX_PI (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); } } break; case PTHREAD_MUTEX_PP_RECURSIVE_NP: case PTHREAD_MUTEX_PP_ERRORCHECK_NP: case PTHREAD_MUTEX_PP_NORMAL_NP: case PTHREAD_MUTEX_PP_ADAPTIVE_NP: { int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; oldval = mutex->__data.__lock; /* Check whether we already hold the mutex. */ if (mutex->__data.__owner == id) { if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) return EDEADLK; if (kind == PTHREAD_MUTEX_RECURSIVE_NP) { /* Just bump the counter. */ if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) /* Overflow of the counter. */ return EAGAIN; ++mutex->__data.__count; return 0; } } int oldprio = -1, ceilval; do { int ceiling = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT; if (__pthread_current_priority () > ceiling) { if (oldprio != -1) __pthread_tpp_change_priority (oldprio, -1); return EINVAL; } int retval = __pthread_tpp_change_priority (oldprio, ceiling); if (retval) return retval; ceilval = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT; oldprio = ceiling; oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, #ifdef NO_INCR ceilval | 2, #else ceilval | 1, #endif ceilval); if (oldval == ceilval) break; do { oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, ceilval | 2, ceilval | 1); if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval) break; if (oldval != ceilval) lll_futex_wait (&mutex->__data.__lock, ceilval | 2, PTHREAD_MUTEX_PSHARED (mutex)); } while (atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, ceilval | 2, ceilval) != ceilval); } while ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval); assert (mutex->__data.__owner == 0); mutex->__data.__count = 1; } break; default: /* Correct code cannot set any other type. */ return EINVAL; }
hp_timing_t __get_clockfreq (void) { /* We read the information from the /proc filesystem. /proc/cpuinfo contains at least one line like: timebase : 33333333 We search for this line and convert the number into an integer. */ static hp_timing_t timebase_freq; hp_timing_t result = 0L; /* If this function was called before, we know the result. */ if (timebase_freq != 0) return timebase_freq; /* If we can use the vDSO to obtain the timebase even better. */ #ifdef SHARED INTERNAL_SYSCALL_DECL (err); timebase_freq = INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK (get_tbfreq, err, hp_timing_t, 0); if (INTERNAL_SYSCALL_ERROR_P (timebase_freq, err) && INTERNAL_SYSCALL_ERRNO (timebase_freq, err) == ENOSYS) #endif { int fd = __open ("/proc/cpuinfo", O_RDONLY); if (__builtin_expect (fd != -1, 1)) { /* The timebase will be in the 1st 1024 bytes for systems with up to 8 processors. If the first read returns less then 1024 bytes read, we have the whole cpuinfo and can start the scan. Otherwise we will have to read more to insure we have the timebase value in the scan. */ char buf[1024]; ssize_t n; n = __read (fd, buf, sizeof (buf)); if (n == sizeof (buf)) { /* We are here because the 1st read returned exactly sizeof (buf) bytes. This implies that we are not at EOF and may not have read the timebase value yet. So we need to read more bytes until we know we have EOF. We copy the lower half of buf to the upper half and read sizeof (buf)/2 bytes into the lower half of buf and repeat until we reach EOF. We can assume that the timebase will be in the last 512 bytes of cpuinfo, so two 512 byte half_bufs will be sufficient to contain the timebase and will handle the case where the timebase spans the half_buf boundry. */ const ssize_t half_buf = sizeof (buf) / 2; while (n >= half_buf) { memcpy (buf, buf + half_buf, half_buf); n = __read (fd, buf + half_buf, half_buf); } if (n >= 0) n += half_buf; } if (__builtin_expect (n, 1) > 0) { char *mhz = memmem (buf, n, "timebase", 7); if (__builtin_expect (mhz != NULL, 1)) { char *endp = buf + n; /* Search for the beginning of the string. */ while (mhz < endp && (*mhz < '0' || *mhz > '9') && *mhz != '\n') ++mhz; while (mhz < endp && *mhz != '\n') { if (*mhz >= '0' && *mhz <= '9') { result *= 10; result += *mhz - '0'; } ++mhz; } } timebase_freq = result; } __close (fd); } } return timebase_freq; }
static int do_clone (struct pthread *pd, const struct pthread_attr *attr, int clone_flags, int (*fct) (void *), STACK_VARIABLES_PARMS, int stopped) { #ifdef PREPARE_CREATE PREPARE_CREATE; #endif if (__builtin_expect (stopped != 0, 0)) /* We make sure the thread does not run far by forcing it to get a lock. We lock it here too so that the new thread cannot continue until we tell it to. */ lll_lock (pd->lock, LLL_PRIVATE); /* One more thread. We cannot have the thread do this itself, since it might exist but not have been scheduled yet by the time we've returned and need to check the value to behave correctly. We must do it before creating the thread, in case it does get scheduled first and then might mistakenly think it was the only thread. In the failure case, we momentarily store a false value; this doesn't matter because there is no kosher thing a signal handler interrupting us right here can do that cares whether the thread count is correct. */ atomic_increment (&__nptl_nthreads); int rc = ARCH_CLONE (fct, STACK_VARIABLES_ARGS, clone_flags, pd, &pd->tid, TLS_VALUE, &pd->tid); if (__builtin_expect (rc == -1, 0)) { atomic_decrement (&__nptl_nthreads); /* Oops, we lied for a second. */ /* Perhaps a thread wants to change the IDs and if waiting for this stillborn thread. */ if (__builtin_expect (atomic_exchange_acq (&pd->setxid_futex, 0) == -2, 0)) lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE); /* Free the resources. */ __deallocate_stack (pd); /* We have to translate error codes. */ return errno == ENOMEM ? EAGAIN : errno; } /* Now we have the possibility to set scheduling parameters etc. */ if (__builtin_expect (stopped != 0, 0)) { INTERNAL_SYSCALL_DECL (err); int res = 0; /* Set the affinity mask if necessary. */ if (attr->cpuset != NULL) { res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, attr->cpusetsize, attr->cpuset); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) { /* The operation failed. We have to kill the thread. First send it the cancellation signal. */ INTERNAL_SYSCALL_DECL (err2); err_out: (void) INTERNAL_SYSCALL (tgkill, err2, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); /* We do not free the stack here because the canceled thread itself will do this. */ return (INTERNAL_SYSCALL_ERROR_P (res, err) ? INTERNAL_SYSCALL_ERRNO (res, err) : 0); } } /* Set the scheduling parameters. */ if ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0) { res = INTERNAL_SYSCALL (sched_setscheduler, err, 3, pd->tid, pd->schedpolicy, &pd->schedparam); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) goto err_out; } } /* We now have for sure more than one thread. The main thread might not yet have the flag set. No need to set the global variable again if this is what we use. */ THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1); return 0; }
/* Get information about the file NAME in BUF. */ int __fxstatat (int vers, int fd, const char *file, struct stat *st, int flag) { INTERNAL_SYSCALL_DECL (err); int result, errno_out; /* ??? The __fxstatat entry point is new enough that it must be using vers == _STAT_VER_KERNEL64. For the benefit of dl-fxstatat64.c, we cannot actually check this, lest the compiler not optimize the rest of the function away. */ #ifdef __NR_fstatat64 if (__have_atfcts >= 0) { result = INTERNAL_SYSCALL (fstatat64, err, 4, fd, file, st, flag); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return result; errno_out = INTERNAL_SYSCALL_ERRNO (result, err); #ifndef __ASSUME_ATFCTS if (errno_out == ENOSYS) __have_atfcts = -1; else #endif { __set_errno (errno_out); return -1; } } #endif /* __NR_fstatat64 */ if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); if (__builtin_expect (filelen == 0, 0)) { __set_errno (ENOENT); return -1; } static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } #ifdef __NR_stat64 if (!__libc_missing_axp_stat64) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat64, err, 2, file, st); else result = INTERNAL_SYSCALL (stat64, err, 2, file, st); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return result; errno_out = INTERNAL_SYSCALL_ERRNO (result, err); # if __ASSUME_STAT64_SYSCALL == 0 if (errno_out == ENOSYS) __libc_missing_axp_stat64 = 1; else # endif goto fail; } #endif /* __NR_stat64 */ struct kernel_stat kst; if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, file, &kst); else result = INTERNAL_SYSCALL (stat, err, 2, file, &kst); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat_conv (vers, &kst, st); errno_out = INTERNAL_SYSCALL_ERRNO (result, err); fail: __atfct_seterrno (errno_out, fd, buf); return -1; }
int fchownat (int fd, const char *file, uid_t owner, gid_t group, int flag) { int result; #ifdef __NR_fchownat # ifndef __ASSUME_ATFCTS if (__have_atfcts >= 0) # endif { result = INLINE_SYSCALL (fchownat, 5, fd, file, owner, group, flag); # ifndef __ASSUME_ATFCTS if (result == -1 && errno == ENOSYS) __have_atfcts = -1; else # endif return result; } #endif #ifndef __ASSUME_ATFCTS if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); if (__builtin_expect (filelen == 0, 0)) { __set_errno (ENOENT); return -1; } static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } INTERNAL_SYSCALL_DECL (err); if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown32, err, 3, CHECK_STRING (file), owner, group); else result = INTERNAL_SYSCALL (chown32, err, 3, CHECK_STRING (file), owner, group); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) { __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); return -1; } return result; #endif }
int __fxstatat64 (int vers, int fd, const char *file, struct stat64 *st, int flag) { if (__builtin_expect (vers != _STAT_VER_LINUX, 0)) { __set_errno (EINVAL); return -1; } int result; INTERNAL_SYSCALL_DECL (err); #ifdef __NR_fstatat64 # ifndef __ASSUME_ATFCTS if (__have_atfcts >= 0) # endif { result = INTERNAL_SYSCALL (fstatat64, err, 4, fd, file, st, flag); # ifndef __ASSUME_ATFCTS if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1) && INTERNAL_SYSCALL_ERRNO (result, err) == ENOSYS) __have_atfcts = -1; else # endif if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return 0; else { __set_errno (INTERNAL_SYSCALL_ERRNO (result, err)); return -1; } } #endif #ifndef __ASSUME_ATFCTS if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } # if __ASSUME_STAT64_SYSCALL > 0 if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat64, err, 2, CHECK_STRING (file), CHECK_1 (st)); else result = INTERNAL_SYSCALL (stat64, err, 2, CHECK_STRING (file), CHECK_1 (st)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) { # if defined _HAVE_STAT64___ST_INO && __ASSUME_ST_INO_64_BIT == 0 if (st->__st_ino != (__ino_t) st->st_ino) st->st_ino = st->__st_ino; # endif return result; } # else struct kernel_stat kst; # ifdef __NR_stat64 if (! __have_no_stat64) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat64, err, 2, CHECK_STRING (file), CHECK_1 (st)); else result = INTERNAL_SYSCALL (stat64, err, 2, CHECK_STRING (file), CHECK_1 (st)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) { # if defined _HAVE_STAT64___ST_INO && __ASSUME_ST_INO_64_BIT == 0 if (st->__st_ino != (__ino_t) st->st_ino) st->st_ino = st->__st_ino; # endif return result; } if (INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS) goto fail; __have_no_stat64 = 1; } # endif if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lstat, err, 2, CHECK_STRING (file), __ptrvalue (&kst)); else result = INTERNAL_SYSCALL (stat, err, 2, CHECK_STRING (file), __ptrvalue (&kst)); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return __xstat64_conv (vers, &kst, st); fail: # endif __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); return -1; #endif }
int pthread_cancel ( pthread_t th) { volatile struct pthread *pd = (volatile struct pthread *) th; /* Make sure the descriptor is valid. */ if (INVALID_TD_P (pd)) /* Not a valid thread handle. */ return ESRCH; #ifdef SHARED pthread_cancel_init (); #endif int result = 0; int oldval; int newval; do { again: oldval = pd->cancelhandling; newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK; /* Avoid doing unnecessary work. The atomic operation can potentially be expensive if the bug has to be locked and remote cache lines have to be invalidated. */ if (oldval == newval) break; /* If the cancellation is handled asynchronously just send a signal. We avoid this if possible since it's more expensive. */ if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval)) { /* Mark the cancellation as "in progress". */ if (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling, oldval | CANCELING_BITMASK, oldval)) goto again; /* The cancellation handler will take care of marking the thread as canceled. */ INTERNAL_SYSCALL_DECL (err); /* One comment: The PID field in the TCB can temporarily be changed (in fork). But this must not affect this code here. Since this function would have to be called while the thread is executing fork, it would have to happen in a signal handler. But this is no allowed, pthread_cancel is not guaranteed to be async-safe. */ int val; #if defined(__ASSUME_TGKILL) && __ASSUME_TGKILL val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); #else # ifdef __NR_tgkill val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); if (INTERNAL_SYSCALL_ERROR_P (val, err) && INTERNAL_SYSCALL_ERRNO (val, err) == ENOSYS) # endif val = INTERNAL_SYSCALL (tkill, err, 2, pd->tid, SIGCANCEL); #endif if (INTERNAL_SYSCALL_ERROR_P (val, err)) result = INTERNAL_SYSCALL_ERRNO (val, err); break; } } /* Mark the thread as canceled. This has to be done atomically since other bits could be modified as well. */ while (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling, newval, oldval)); return result; }
int fchownat (int fd, const char *file, uid_t owner, gid_t group, int flag) { if (flag & ~AT_SYMLINK_NOFOLLOW) { __set_errno (EINVAL); return -1; } char *buf = NULL; if (fd != AT_FDCWD && file[0] != '/') { size_t filelen = strlen (file); if (__builtin_expect (filelen == 0, 0)) { __set_errno (ENOENT); return -1; } static const char procfd[] = "/proc/self/fd/%d/%s"; /* Buffer for the path name we are going to use. It consists of - the string /proc/self/fd/ - the file descriptor number - the file name provided. The final NUL is included in the sizeof. A bit of overhead due to the format elements compensates for possible negative numbers. */ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen; buf = alloca (buflen); __snprintf (buf, buflen, procfd, fd, file); file = buf; } int result; INTERNAL_SYSCALL_DECL (err); #if __ASSUME_32BITUIDS > 0 if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown32, err, 3, CHECK_STRING (file), owner, group); else result = INTERNAL_SYSCALL (chown32, err, 3, CHECK_STRING (file), owner, group); #else # ifdef __NR_chown32 if (__libc_missing_32bit_uids <= 0) { if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown32, err, 3, CHECK_STRING (file), owner, group); else result = INTERNAL_SYSCALL (chown32, err, 3, CHECK_STRING (file), owner, group); if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1)) return result; if (INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS) goto fail; __libc_missing_32bit_uids = 1; } # endif /* __NR_chown32 */ if (((owner + 1) > (gid_t) ((__kernel_uid_t) -1U)) || ((group + 1) > (gid_t) ((__kernel_gid_t) -1U))) { __set_errno (EINVAL); return -1; } if (flag & AT_SYMLINK_NOFOLLOW) result = INTERNAL_SYSCALL (lchown, err, 3, CHECK_STRING (file), owner, group); else result = INTERNAL_SYSCALL (chown, err, 3, CHECK_STRING (file), owner, group); #endif if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0)) { fail: __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf); result = -1; } return result; }
static int create_thread (struct pthread *pd, const struct pthread_attr *attr, bool stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran) { /* Determine whether the newly created threads has to be started stopped since we have to set the scheduling parameters or set the affinity. */ if (attr != NULL && (__glibc_unlikely (attr->cpuset != NULL) || __glibc_unlikely ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0))) stopped_start = true; pd->stopped_start = stopped_start; if (__glibc_unlikely (stopped_start)) /* We make sure the thread does not run far by forcing it to get a lock. We lock it here too so that the new thread cannot continue until we tell it to. */ lll_lock (pd->lock, LLL_PRIVATE); /* We rely heavily on various flags the CLONE function understands: CLONE_VM, CLONE_FS, CLONE_FILES These flags select semantics with shared address space and file descriptors according to what POSIX requires. CLONE_SIGHAND, CLONE_THREAD This flag selects the POSIX signal semantics and various other kinds of sharing (itimers, POSIX timers, etc.). CLONE_SETTLS The sixth parameter to CLONE determines the TLS area for the new thread. CLONE_PARENT_SETTID The kernels writes the thread ID of the newly created thread into the location pointed to by the fifth parameters to CLONE. Note that it would be semantically equivalent to use CLONE_CHILD_SETTID but it is be more expensive in the kernel. CLONE_CHILD_CLEARTID The kernels clears the thread ID of a thread that has called sys_exit() in the location pointed to by the seventh parameter to CLONE. The termination signal is chosen to be zero which means no signal is sent. */ const int clone_flags = (CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SYSVSEM | CLONE_SIGHAND | CLONE_THREAD | CLONE_SETTLS | CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID | 0); TLS_DEFINE_INIT_TP (tp, pd); if (__glibc_unlikely (ARCH_CLONE (&start_thread, STACK_VARIABLES_ARGS, clone_flags, pd, &pd->tid, tp, &pd->tid) == -1)) return errno; /* It's started now, so if we fail below, we'll have to cancel it and let it clean itself up. */ *thread_ran = true; /* Now we have the possibility to set scheduling parameters etc. */ if (attr != NULL) { INTERNAL_SYSCALL_DECL (err); int res; /* Set the affinity mask if necessary. */ if (attr->cpuset != NULL) { assert (stopped_start); res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, attr->cpusetsize, attr->cpuset); if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (res, err))) err_out: { /* The operation failed. We have to kill the thread. We let the normal cancellation mechanism do the work. */ INTERNAL_SYSCALL_DECL (err2); (void) INTERNAL_SYSCALL (tgkill, err2, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); return INTERNAL_SYSCALL_ERRNO (res, err); } } /* Set the scheduling parameters. */ if ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0) { assert (stopped_start); res = INTERNAL_SYSCALL (sched_setscheduler, err, 3, pd->tid, pd->schedpolicy, &pd->schedparam); if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (res, err))) goto err_out; } } return 0; }
static int do_clone (struct pthread *pd, const struct pthread_attr *attr, int clone_flags, int (*fct) (void *), STACK_VARIABLES_PARMS, int stopped) { #ifdef PREPARE_CREATE PREPARE_CREATE; #endif if (stopped) /* We Make sure the thread does not run far by forcing it to get a lock. We lock it here too so that the new thread cannot continue until we tell it to. */ lll_lock (pd->lock); /* One more thread. We cannot have the thread do this itself, since it might exist but not have been scheduled yet by the time we've returned and need to check the value to behave correctly. We must do it before creating the thread, in case it does get scheduled first and then might mistakenly think it was the only thread. In the failure case, we momentarily store a false value; this doesn't matter because there is no kosher thing a signal handler interrupting us right here can do that cares whether the thread count is correct. */ atomic_increment (&__nptl_nthreads); if (ARCH_CLONE (fct, STACK_VARIABLES_ARGS, clone_flags, pd, &pd->tid, TLS_VALUE, &pd->tid) == -1) { atomic_decrement (&__nptl_nthreads); /* Oops, we lied for a second. */ /* Failed. If the thread is detached, remove the TCB here since the caller cannot do this. The caller remembered the thread as detached and cannot reverify that it is not since it must not access the thread descriptor again. */ if (IS_DETACHED (pd)) __deallocate_stack (pd); return errno; } /* Now we have the possibility to set scheduling parameters etc. */ if (__builtin_expect (stopped != 0, 0)) { INTERNAL_SYSCALL_DECL (err); int res = 0; /* Set the affinity mask if necessary. */ if (attr->cpuset != NULL) { res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, sizeof (cpu_set_t), attr->cpuset); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) { /* The operation failed. We have to kill the thread. First send it the cancellation signal. */ INTERNAL_SYSCALL_DECL (err2); err_out: #if __ASSUME_TGKILL (void) INTERNAL_SYSCALL (tgkill, err2, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); #else (void) INTERNAL_SYSCALL (tkill, err2, 2, pd->tid, SIGCANCEL); #endif return (INTERNAL_SYSCALL_ERROR_P (res, err) ? INTERNAL_SYSCALL_ERRNO (res, err) : 0); } } /* Set the scheduling parameters. */ if ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0) { res = INTERNAL_SYSCALL (sched_setscheduler, err, 3, pd->tid, pd->schedpolicy, &pd->schedparam); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) goto err_out; } } /* We now have for sure more than one thread. The main thread might not yet have the flag set. No need to set the global variable again if this is what we use. */ THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1); return 0; }
static int do_clone (struct pthread *pd, const struct pthread_attr *attr, int clone_flags, int (*fct) (void *), STACK_VARIABLES_PARMS, int stopped) { #if 0 PREPARE_CREATE; #endif if (__builtin_expect (stopped != 0, 0)) /* We make sure the thread does not run far by forcing it to get a lock. We lock it here too so that the new thread cannot continue until we tell it to. */ lll_lock (pd->lock, LLL_PRIVATE); /* One more thread. We cannot have the thread do this itself, since it might exist but not have been scheduled yet by the time we've returned and need to check the value to behave correctly. We must do it before creating the thread, in case it does get scheduled first and then might mistakenly think it was the only thread. In the failure case, we momentarily store a false value; this doesn't matter because there is no kosher thing a signal handler interrupting us right here can do that cares whether the thread count is correct. */ atomic_increment (&__nptl_nthreads); #if !defined(__native_client__) && !defined(__ZRT_HOST) #error "This code was changed to work only in Native Client" #endif /* Native Client does not have a notion of a thread ID, so we make one up. This must be small enough to leave space for number identifying the clock. Use CLOCK_IDFIELD_SIZE to guarantee that. */ pd->tid = ((unsigned int) pd) >> CLOCK_IDFIELD_SIZE; /* Native Client syscall thread_create does not push return address onto stack as opposed to the kernel. We emulate this behavior on x86-64 to meet the ABI requirement ((%rsp + 8) mod 16 == 0). On x86-32 the attribute 'force_align_arg_pointer' does the same for start_thread (). */ #ifdef __x86_64__ STACK_VARIABLES_ARGS -= 8; #endif if (__nacl_irt_thread_create (fct, STACK_VARIABLES_ARGS, pd) != 0) { pd->tid = 0; atomic_decrement (&__nptl_nthreads); /* Oops, we lied for a second. */ /* Failed. If the thread is detached, remove the TCB here since the caller cannot do this. The caller remembered the thread as detached and cannot reverify that it is not since it must not access the thread descriptor again. */ if (IS_DETACHED (pd)) __deallocate_stack (pd); /* We have to translate error codes. */ return errno == ENOMEM ? EAGAIN : errno; } /* Now we have the possibility to set scheduling parameters etc. */ if (__builtin_expect (stopped != 0, 0)) { INTERNAL_SYSCALL_DECL (err); int res = 0; /* Set the affinity mask if necessary. */ if (attr->cpuset != NULL) { res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid, attr->cpusetsize, attr->cpuset); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) { /* The operation failed. We have to kill the thread. First send it the cancellation signal. */ INTERNAL_SYSCALL_DECL (err2); err_out: #if __ASSUME_TGKILL (void) INTERNAL_SYSCALL (tgkill, err2, 3, THREAD_GETMEM (THREAD_SELF, pid), pd->tid, SIGCANCEL); #else (void) INTERNAL_SYSCALL (tkill, err2, 2, pd->tid, SIGCANCEL); #endif return (INTERNAL_SYSCALL_ERROR_P (res, err) ? INTERNAL_SYSCALL_ERRNO (res, err) : 0); } } /* Set the scheduling parameters. */ if ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0) { res = INTERNAL_SYSCALL (sched_setscheduler, err, 3, pd->tid, pd->schedpolicy, &pd->schedparam); if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (res, err), 0)) goto err_out; } } /* We now have for sure more than one thread. The main thread might not yet have the flag set. No need to set the global variable again if this is what we use. */ THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1); return 0; }