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-rw-r--r--sysdeps/nacl/pthread-pids.h68
1 files changed, 0 insertions, 68 deletions
diff --git a/sysdeps/nacl/pthread-pids.h b/sysdeps/nacl/pthread-pids.h
deleted file mode 100644
index 80cd98e06a..0000000000
--- a/sysdeps/nacl/pthread-pids.h
+++ /dev/null
@@ -1,68 +0,0 @@
-/* Initialize pid and tid fields of struct pthread. NaCl version.
- Copyright (C) 2015-2016 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <pthreadP.h>
-
-
-/* NaCl has no concept of PID or TID, nor even any notion of an
- identifier for a thread within the process. But various places in
- the NPTL implementation rely on using the 'tid' field of the TCB
- (struct pthread) as an identifier that is unique at least among all
- live threads in the process. So we must synthesize some number to
- use. Conveniently, the 'pthread_t' value itself is already unique
- in exactly this way (because it's the 'struct pthread' pointer).
-
- The only wrinkle is that 'tid' is a (32-bit) 'int' and its high
- (sign) bit is used for special purposes, so we must be absolutely
- sure that we never use a pointer value with the high bit set. (It
- also cannot be zero, but zero is never a valid pointer anyway.)
- The NaCl sandbox models for 32-bit machines limit the address space
- to less than 3GB (in fact, to 1GB), so it's already impossible that
- a valid pointer will have its high bit set. But the NaCl x86-64
- sandbox model allows a full 4GB of address space, so we cannot
- assume that an arbitrary pointer value will not have the high bit
- set. Conveniently, there are always unused bits in the pointer
- value for a 'struct pthread', because it is always aligned to at
- least 32 bits and so the low bits are always zero. Hence, we can
- safely avoid the danger of a nonzero high bit just by shifting the
- pointer value right. */
-
-static inline int
-__nacl_get_tid (struct pthread *pd)
-{
- uintptr_t id = (uintptr_t) pd;
- int tid = id >> 1;
- assert ((id & 1) == 0);
- assert (sizeof id == sizeof tid);
- assert (tid > 0);
- /* This ensures that NACL_EXITING_TID (lowlevellock.h) can never
- be a valid TID value. */
- assert ((tid & 1) == 0);
- return tid;
-}
-
-
-/* Initialize PD->pid and PD->tid for the initial thread. If there is
- setup required to arrange that __exit_thread causes PD->tid to be
- cleared and futex-woken, then this function should do that as well. */
-static inline void
-__pthread_initialize_pids (struct pthread *pd)
-{
- pd->tid = __nacl_get_tid (pd);
- pd->pid = -1;
-}