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Re: [PATCH] nptl: Add pthread_thread_number_np function
On 12/22/2017 09:02 PM, Joseph Myers wrote:
On Fri, 22 Dec 2017, Florian Weimer wrote:
As with any patch changing the installed pthread.h, the separate hppa
version of that header needs the same change applied.
In the attached patch, I added <bits/pthread-common.h> to simplify this. I
verified that it is installed as $(DESTDIR)/usr/include/bits/pthread-common.h.
Since almost everything in pthread.h is common, I don't think it makes
sense to have bits/pthread-common.h just for this one declaration.
Rather, I think there should be e.g. bits/pthread-initializers.h, for
which hppa would have a different version.
(If at some point Hurd libpthread gets merged in, it may be desirable to
share as much as possible of the installed header declaring the API, and
the testcases, between the two pthreads implementations, but for now it
would be premature to try to distinguish between headers/tests for glibc
pthreads and those specifically for the NPTL implementation thereof; Hurd
people would need to take the lead on such refactoring at an appropriate
point.)
Okay, so this instead?
Thanks,
Florian
Subject: [PATCH] nptl: Add pthread_thread_number_np function
To: libc-alpha@sourceware.org
The implementation is actually in libc.so. With a full implementation
of pthread_self in libc.so, pthread_thread_number_np is completely
usable without libpthread.
2017-12-22 Florian Weimer <fweimer@redhat.com>
nptl: Add pthread_thread_number_np function.
* csu/libc-tls.c (__libc_setup_tls): Call __dl_inittcb.
* elf/Makefile (dl-routines): Add dl-inittcb.
* elf/dl-inittcb.c: New file.
* elf/rtld.c (init_tls): Call __dl_inittcb.
* manual/threads.texi (Non-POSIX Extensions): Reference Non-POSIX
Extensions.
(Non-POSIX Extensions): New node.
* nptl/Makefile (routines): Add thread_number.
(tests): Add tst-thread_number-single, tst-thread_number-multi,
tst-thread_number-single-static, tst-thread_number-multi-static.
(tests-nolibpthread): Add tst-thread_number-single,
tst-thread_number-single-static.
(tests-static): Add tst-thread_number-single-static,
tst-thread_number-multi-static.
* nptl/Versions (GLIBC_2.27): Export pthread_thread_number_np.
* nptl/allocatestack.c (allocate_stack): Increment
global_thread_number under__default_pthread_attr_lock and use its
value to set the new thread number.
* nptl/descr.h (struct pthread): Add number member.
* nptl/thread_number.c: New file.
* nptl/tst-thread_number-multi.c: Likewise.
* nptl/tst-thread_number-single.c: Likewise.
* nptl/tst-thread_number-multi-static.c: Likewise.
* nptl/tst-thread_number-single-static.c: Likewise.
* sysdeps/nptl/pthread.h (pthread_thread_number_np): Declare.
* sysdeps/unix/sysv/linux/hppa/pthread.h (pthread_thread_number_np):
Likewise.
* sysdeps/unix/sysv/linux/libc**.abilist: Update.
diff --git a/NEWS b/NEWS
index 2a1a4bfd85..3fd41915ed 100644
--- a/NEWS
+++ b/NEWS
@@ -55,7 +55,8 @@ Major new features:
_Float32x types, as defined by ISO/IEC TS 18661-3:2015. These are
corresponding interfaces to those supported for _Float128.
-* glibc now implements the memfd_create and mlock2 functions on Linux.
+* glibc now implements the memfd_create, mlock2, and
+ pthread_thread_number_np functions on Linux.
* Support for memory protection keys was added. The <sys/mman.h> header now
declares the functions pkey_alloc, pkey_free, pkey_mprotect, pkey_set,
diff --git a/csu/libc-tls.c b/csu/libc-tls.c
index 1f8ddaf543..dceb01e533 100644
--- a/csu/libc-tls.c
+++ b/csu/libc-tls.c
@@ -195,6 +195,7 @@ __libc_setup_tls (void)
#endif
if (__builtin_expect (lossage != NULL, 0))
_startup_fatal (lossage);
+ __dl_inittcb ();
/* Update the executable's link map with enough information to make
the TLS routines happy. */
diff --git a/elf/Makefile b/elf/Makefile
index a987614b6f..bf2928e958 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -31,7 +31,7 @@ routines = $(all-dl-routines) dl-support dl-iteratephdr \
# profiled libraries.
dl-routines = $(addprefix dl-,load lookup object reloc deps hwcaps \
runtime init fini debug misc \
- version profile tls origin scope \
+ version profile tls inittcb origin scope \
execstack caller open close trampoline \
exception sort-maps)
ifeq (yes,$(use-ldconfig))
diff --git a/elf/dl-inittcb.c b/elf/dl-inittcb.c
new file mode 100644
index 0000000000..5a70e9775d
--- /dev/null
+++ b/elf/dl-inittcb.c
@@ -0,0 +1,22 @@
+/* Initialize TCB contents. Generic version.
+ Copyright (C) 2017 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/>. */
+
+void
+__dl_inittcb (void)
+{
+}
diff --git a/elf/rtld.c b/elf/rtld.c
index c01b7e3641..6eb51f689b 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -740,6 +740,7 @@ cannot allocate TLS data structures for initial thread\n");
const char *lossage = TLS_INIT_TP (tcbp);
if (__glibc_unlikely (lossage != NULL))
_dl_fatal_printf ("cannot set up thread-local storage: %s\n", lossage);
+ __dl_inittcb ();
tls_init_tp_called = true;
return tcbp;
diff --git a/manual/threads.texi b/manual/threads.texi
index 769d974d50..6aa08f398a 100644
--- a/manual/threads.texi
+++ b/manual/threads.texi
@@ -80,6 +80,7 @@ the standard.
@menu
* Default Thread Attributes:: Setting default attributes for
threads in a process.
+* Identifying Threads:: Unique identifiers for threads.
@end menu
@node Default Thread Attributes
@@ -124,6 +125,30 @@ The system does not have sufficient memory.
@end table
@end deftypefun
+@node Identifying Threads
+@subsection Unique identifiers for threads
+
+@Theglibc{} provides a non-standard function to obtain a unique thread
+identifier.
+
+@deftypefun uint64_t pthread_thread_number_np (pthread_t @var{thread})
+@standards{GNU, pthread.h}
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
+
+This function returns a number that uniquely identifies @var{thread}
+among all past, current, and future running threads. This number does
+not change during the life-time of the thread. Once returned by this
+function, a number will not be reused after the thread terminates.
+
+The returned number is only unique with regards to the current process.
+It may be shared by subprocesses and other processes in the system.
+
+The initial (main) thread has number 1. Thread numbers are not
+necessarily assigned in a consecutive fashion. They bear no
+relationship to POSIX thread IDs (@code{pthread_t} values), process IDs
+or thread IDs assigned by the kernel.
+@end deftypefun
+
@c FIXME these are undocumented:
@c pthread_atfork
@c pthread_attr_destroy
diff --git a/nptl/Makefile b/nptl/Makefile
index cf2ba8131b..6f20d4e07d 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -31,7 +31,7 @@ install-lib-ldscripts := libpthread.so
routines = alloca_cutoff forward libc-lowlevellock libc-cancellation \
libc-cleanup libc_pthread_init libc_multiple_threads \
- register-atfork unregister-atfork pthread_self
+ register-atfork unregister-atfork pthread_self thread_number
shared-only-routines = forward
# We need to provide certain routines for compatibility with existing
@@ -304,7 +304,8 @@ tests = tst-attr1 tst-attr2 tst-attr3 tst-default-attr \
c89 gnu89 c99 gnu99 c11 gnu11) \
tst-bad-schedattr \
tst-thread_local1 tst-mutex-errorcheck tst-robust10 \
- tst-robust-fork tst-create-detached tst-memstream
+ tst-robust-fork tst-create-detached tst-memstream \
+ tst-thread_number-single tst-thread_number-multi \
tests-internal := tst-rwlock19 tst-rwlock20 \
tst-sem11 tst-sem12 tst-sem13 \
@@ -320,7 +321,9 @@ test-srcs = tst-oddstacklimit
test-xfail-tst-once5 = yes
# Files which must not be linked with libpthread.
-tests-nolibpthread = tst-unload
+tests-nolibpthread = tst-unload \
+ tst-thread_number-single \
+ tst-thread_number-single-static \
gen-as-const-headers = pthread-errnos.sym \
unwindbuf.sym \
@@ -435,9 +438,13 @@ link-libc-static := $(common-objpfx)libc.a $(static-gnulib) \
tests-static += tst-locale1 tst-locale2 tst-stackguard1-static \
tst-cancel21-static tst-cancel24-static tst-cond8-static \
tst-mutex8-static tst-mutexpi8-static tst-sem11-static \
- tst-sem12-static
+ tst-sem12-static tst-thread_number-single-static \
+ tst-thread_number-multi-static \
+
tests += tst-cancel21-static tst-cancel24-static \
- tst-cond8-static
+ tst-cond8-static tst-thread_number-single-static \
+ tst-thread_number-multi-static \
+
tests-internal += tst-sem11-static tst-sem12-static tst-stackguard1-static
xtests-static += tst-setuid1-static
diff --git a/nptl/Versions b/nptl/Versions
index 0ae5def464..a7204912a8 100644
--- a/nptl/Versions
+++ b/nptl/Versions
@@ -28,6 +28,9 @@ libc {
pthread_cond_wait; pthread_cond_signal;
pthread_cond_broadcast; pthread_cond_timedwait;
}
+ GLIBC_2.27 {
+ pthread_thread_number_np;
+ }
GLIBC_PRIVATE {
__libc_alloca_cutoff;
# Internal libc interface to libpthread
diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
index 1cc7893195..454df7740b 100644
--- a/nptl/allocatestack.c
+++ b/nptl/allocatestack.c
@@ -413,16 +413,28 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
assert (powerof2 (pagesize_m1 + 1));
assert (TCB_ALIGNMENT >= STACK_ALIGN);
- /* Get the stack size from the attribute if it is set. Otherwise we
- use the default we determined at start time. */
- if (attr->stacksize != 0)
- size = attr->stacksize;
- else
- {
- lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
+ uint64_t thread_number;
+ lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
+ {
+ /* Number 1 is reserved for the initial thread. Reuse
+ __default_pthread_attr_lock to avoid concurrent updates of this
+ counter. */
+ static uint64_t global_thread_number = 1;
+ thread_number = ++global_thread_number;
+
+ /* Check for counter wrap-around. This should never happen
+ because 2**64 is such a large value. */
+ if (thread_number == 0)
+ __libc_fatal ("Fatal glibc error: maximum number of threads exceeded\n");
+
+ /* Get the stack size from the attribute if it is set. Otherwise
+ we use the default we determined at start time. */
+ if (attr->stacksize != 0)
+ size = attr->stacksize;
+ else
size = __default_pthread_attr.stacksize;
- lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
- }
+ }
+ lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
/* Get memory for the stack. */
if (__glibc_unlikely (attr->flags & ATTR_FLAG_STACKADDR))
@@ -758,6 +770,8 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
#endif
pd->robust_head.list = &pd->robust_head;
+ pd->number = thread_number;
+
/* We place the thread descriptor at the end of the stack. */
*pdp = pd;
diff --git a/nptl/descr.h b/nptl/descr.h
index fdeb397eab..7c6e34a636 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -398,6 +398,9 @@ struct pthread
/* Resolver state. */
struct __res_state res;
+ /* Unique number assigned to this thread. */
+ uint64_t number;
+
/* This member must be last. */
char end_padding[];
diff --git a/nptl/thread_number.c b/nptl/thread_number.c
new file mode 100644
index 0000000000..30b7f438c3
--- /dev/null
+++ b/nptl/thread_number.c
@@ -0,0 +1,36 @@
+/* Unique numbers for threads.
+ Copyright (C) 2017 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"
+
+/* This function should ideally return an integer wider than uint64_t,
+ so that the thread number can never-ever overflow. We may have to
+ switch to a 128-bit return value for new architectures
+ (particularly if those provide atomic operations on 128-bit
+ integers). But with current architectures, the baked-in limit of
+ 2**64 threads ever created by a process is not a problem because
+ architectural constraints result in a thread creation rate far
+ below one billion threads per second, and even at that rate, a
+ 64-bit counter lasts for hundreds of years. */
+
+__uint64_t
+pthread_thread_number_np (pthread_t threadid)
+{
+ struct pthread *pd = (struct pthread *) threadid;
+ return pd->number;
+}
diff --git a/nptl/tst-thread_number-multi-static.c b/nptl/tst-thread_number-multi-static.c
new file mode 100644
index 0000000000..658928cfd5
--- /dev/null
+++ b/nptl/tst-thread_number-multi-static.c
@@ -0,0 +1,19 @@
+/* Test unique numbers for threads, static multi-threaded version.
+ Copyright (C) 2017 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 "tst-thread_number-multi.c"
diff --git a/nptl/tst-thread_number-multi.c b/nptl/tst-thread_number-multi.c
new file mode 100644
index 0000000000..881fe6b097
--- /dev/null
+++ b/nptl/tst-thread_number-multi.c
@@ -0,0 +1,101 @@
+/* Test unique numbers for threads, non-static multi-threaded version.
+ Copyright (C) 2017 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 <pthread.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/xthread.h>
+
+/* Used to check that the main thread still has thread number 1 in a
+ subprocess. */
+static void
+subprocess (void *closure)
+{
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+}
+
+static void *
+subthread (void *closure)
+{
+ if (closure != NULL)
+ xpthread_barrier_wait (closure);
+ return NULL;
+}
+
+static int
+compare (const void *pleft, const void *pright)
+{
+ uint64_t left = *(const uint64_t *)pleft;
+ uint64_t right = *(const uint64_t *)pright;
+ if (left < right)
+ return -1;
+ if (left > right)
+ return 1;
+ return 0;
+}
+
+static int
+do_test (void)
+{
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+ support_isolate_in_subprocess (subprocess, NULL);
+
+ /* Create thread_count threads, half of which are joined
+ immediately, have of which stay around. */
+ enum { thread_count = 10 };
+ pthread_barrier_t barrier;
+ xpthread_barrier_init (&barrier, NULL, thread_count / 2 + 1);
+ uint64_t ids[thread_count];
+ pthread_t threads[thread_count]; /* Only even-numbered entries are valid. */
+ for (int i = 0; i < thread_count; ++i)
+ {
+ bool stay_around = (i % 2) == 0;
+ threads[i] = xpthread_create (NULL, subthread,
+ stay_around ? &barrier : NULL);
+ ids[i] = pthread_thread_number_np (threads[i]);
+ TEST_VERIFY (ids[i] != 1);
+ if (!stay_around)
+ xpthread_join (threads[i]);
+ }
+
+ /* Check that the IDs are all distinct. */
+ qsort (ids, thread_count, sizeof (ids[0]), compare);
+ for (int i = 1; i < thread_count; ++i)
+ TEST_VERIFY (ids[i - 1] < ids[i]);
+
+ /* Main thread ID should remain at 1. */
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+ support_isolate_in_subprocess (subprocess, NULL);
+
+ /* Clean up. */
+ xpthread_barrier_wait (&barrier);
+ for (int i = 0; i < thread_count; ++i)
+ if ((i % 2) == 0)
+ xpthread_join (threads[i]);
+
+ /* Main thread ID should still remain at 1. */
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+ support_isolate_in_subprocess (subprocess, NULL);
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/nptl/tst-thread_number-single-static.c b/nptl/tst-thread_number-single-static.c
new file mode 100644
index 0000000000..5c21063c36
--- /dev/null
+++ b/nptl/tst-thread_number-single-static.c
@@ -0,0 +1,19 @@
+/* Test unique numbers for threads, static single-threaded version.
+ Copyright (C) 2017 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 "tst-thread_number-single.c"
diff --git a/nptl/tst-thread_number-single.c b/nptl/tst-thread_number-single.c
new file mode 100644
index 0000000000..7d3e7ee1dd
--- /dev/null
+++ b/nptl/tst-thread_number-single.c
@@ -0,0 +1,40 @@
+/* Test unique numbers for threads, non-static single-threaded version.
+ Copyright (C) 2017 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 <pthread.h>
+#include <support/check.h>
+#include <support/namespace.h>
+
+/* Used to check that the main thread still has thread number 1 in a
+ subprocess. */
+static void
+subprocess (void *closure)
+{
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+}
+
+static int
+do_test (void)
+{
+ TEST_COMPARE (pthread_thread_number_np (pthread_self ()), 1U);
+ support_isolate_in_subprocess (subprocess, NULL);
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 658a4f20b4..b92e48f1bb 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -1071,6 +1071,10 @@ extern struct link_map * _dl_get_dl_main_map (void)
void __pthread_initialize_minimal (void) weak_function;
#endif
+/* Initialize the already-existing TCB for the main thread. Called
+ during dynamic linker startup or from __libc_setup_tls. */
+void __dl_inittcb (void) attribute_hidden;
+
/* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
extern void *_dl_allocate_tls (void *mem);
rtld_hidden_proto (_dl_allocate_tls)
diff --git a/sysdeps/nptl/dl-inittcb.c b/sysdeps/nptl/dl-inittcb.c
new file mode 100644
index 0000000000..c25424dfa6
--- /dev/null
+++ b/sysdeps/nptl/dl-inittcb.c
@@ -0,0 +1,27 @@
+/* Initialize TCB contents. NPTL version.
+ Copyright (C) 2017 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 <ldsodefs.h>
+#include <tls.h>
+
+void
+__dl_inittcb (void)
+{
+ /* The main thread has number 1. */
+ THREAD_SELF->number = 1;
+}
diff --git a/sysdeps/nptl/pthread.h b/sysdeps/nptl/pthread.h
index 787ac6e4cd..c45b518c5d 100644
--- a/sysdeps/nptl/pthread.h
+++ b/sysdeps/nptl/pthread.h
@@ -1145,6 +1145,10 @@ extern int pthread_atfork (void (*__prepare) (void),
void (*__child) (void)) __THROW;
+/* Return a number uniquely identifying THREAD, even after its
+ termination. */
+__uint64_t pthread_thread_number_np (pthread_t __thread_id) __THROW;
+
#ifdef __USE_EXTERN_INLINES
/* Optimizations. */
__extern_inline int
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index 90c9bc84e1..faa7171f41 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2114,6 +2114,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index fd2d81fb68..e7080beaa4 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2025,6 +2025,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/arm/libc.abilist b/sysdeps/unix/sysv/linux/arm/libc.abilist
index 044ec102c2..a87740050c 100644
--- a/sysdeps/unix/sysv/linux/arm/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/libc.abilist
@@ -115,6 +115,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index 2360130abe..9f28dcf4d1 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -1879,6 +1879,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/hppa/pthread.h b/sysdeps/unix/sysv/linux/hppa/pthread.h
index 3d69ddcd00..cd2addef88 100644
--- a/sysdeps/unix/sysv/linux/hppa/pthread.h
+++ b/sysdeps/unix/sysv/linux/hppa/pthread.h
@@ -1120,6 +1120,9 @@ extern int pthread_atfork (void (*__prepare) (void),
void (*__parent) (void),
void (*__child) (void)) __THROW;
+/* Return a number uniquely identifying THREAD, even after its
+ termination. */
+__uint64_t pthread_thread_number_np (pthread_t __thread_id) __THROW;
#ifdef __USE_EXTERN_INLINES
/* Optimizations. */
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 39c993fd79..f14b9cf624 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2044,6 +2044,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index 68496aa6ac..9aaa06f278 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -1908,6 +1908,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index b676025261..cb06ac5add 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -116,6 +116,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index cdd1df55d0..00ca22237c 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -1993,6 +1993,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/microblaze/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/libc.abilist
index e4265fd74d..7b2d7c183b 100644
--- a/sysdeps/unix/sysv/linux/microblaze/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/libc.abilist
@@ -2114,6 +2114,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index 3a7e0b4c29..e9ab73a95d 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -1968,6 +1968,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index 5e805924fa..2a817eda1f 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -1966,6 +1966,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index 1973fac36d..486aa10a92 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -1964,6 +1964,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index 5e18ab83b4..93fe34b413 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -1959,6 +1959,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index cc5885ab9b..5ff22dd9d2 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2155,6 +2155,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 676aa50c81..8df287ea1e 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -1997,6 +1997,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index 2016c7c1e5..8c86997b4f 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2002,6 +2002,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
index 3d19e38dbd..835e6ae0dd 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
@@ -2209,6 +2209,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
index c57ab21b82..8f23491a62 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist
@@ -116,6 +116,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index 25903720e3..605bc2220d 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -1997,6 +1997,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 5d6800c236..787bbf83b6 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -1898,6 +1898,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/sh/libc.abilist b/sysdeps/unix/sysv/linux/sh/libc.abilist
index c04872ca7f..20ae3fa1aa 100644
--- a/sysdeps/unix/sysv/linux/sh/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/libc.abilist
@@ -1883,6 +1883,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index 85cbe308d6..d6e37b80eb 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -1990,6 +1990,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index f7a1ab8edb..0572308fb1 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -1927,6 +1927,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf128 F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx32/libc.abilist b/sysdeps/unix/sysv/linux/tile/tilegx32/libc.abilist
index ab56ecee44..5e858e2226 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx32/libc.abilist
@@ -2121,6 +2121,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx64/libc.abilist b/sysdeps/unix/sysv/linux/tile/tilegx64/libc.abilist
index f2518c08ff..f10ad6c931 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx64/libc.abilist
@@ -2121,6 +2121,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 2a3cc40674..ea6653b142 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -1885,6 +1885,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 8bc16b9004..8e22fcc12e 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2128,6 +2128,7 @@ GLIBC_2.27 pkey_free F
GLIBC_2.27 pkey_get F
GLIBC_2.27 pkey_mprotect F
GLIBC_2.27 pkey_set F
+GLIBC_2.27 pthread_thread_number_np F
GLIBC_2.27 strfromf32 F
GLIBC_2.27 strfromf32x F
GLIBC_2.27 strfromf64 F