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nptl: Extract <bits/atomic_wide_counter.h> from pthread_cond_common.c 

And make it an installed header.  This addresses a few aliasing
violations (which do not seem to result in miscompilation due to
the use of atomics), and also enables use of wide counters in other
parts of the library.

The debug output in nptl/tst-cond22 has been adjusted to print
the 32-bit values instead because it avoids a big-endian/little-endian
difference.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
This commit is contained in:
Florian Weimer 2021-11-17 12:20:13 +01:00
parent a43c0b5483
commit 8bd336a00a
9 changed files with 320 additions and 208 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
bits/atomic_wide_counter.h Normal file
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@ -0,0 +1,35 @@
/* Monotonically increasing wide counters (at least 62 bits).
Copyright (C) 2016-2021 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
<https://www.gnu.org/licenses/>. */
#ifndef _BITS_ATOMIC_WIDE_COUNTER_H
#define _BITS_ATOMIC_WIDE_COUNTER_H
/* Counter that is monotonically increasing (by less than 2**31 per
increment), with a single writer, and an arbitrary number of
readers. */
typedef union
{
__extension__ unsigned long long int __value64;
struct
{
unsigned int __low;
unsigned int __high;
} __value32;
} __atomic_wide_counter;
#endif /* _BITS_ATOMIC_WIDE_COUNTER_H */

89
include/atomic_wide_counter.h Normal file
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@ -0,0 +1,89 @@
/* Monotonically increasing wide counters (at least 62 bits).
Copyright (C) 2016-2021 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
<https://www.gnu.org/licenses/>. */
#ifndef _ATOMIC_WIDE_COUNTER_H
#define _ATOMIC_WIDE_COUNTER_H
#include <atomic.h>
#include <bits/atomic_wide_counter.h>
#if __HAVE_64B_ATOMICS
static inline uint64_t
__atomic_wide_counter_load_relaxed (__atomic_wide_counter *c)
{
return atomic_load_relaxed (&c->__value64);
}
static inline uint64_t
__atomic_wide_counter_fetch_add_relaxed (__atomic_wide_counter *c,
unsigned int val)
{
return atomic_fetch_add_relaxed (&c->__value64, val);
}
static inline uint64_t
__atomic_wide_counter_fetch_add_acquire (__atomic_wide_counter *c,
unsigned int val)
{
return atomic_fetch_add_acquire (&c->__value64, val);
}
static inline void
__atomic_wide_counter_add_relaxed (__atomic_wide_counter *c,
unsigned int val)
{
atomic_store_relaxed (&c->__value64,
atomic_load_relaxed (&c->__value64) + val);
}
static uint64_t __attribute__ ((unused))
__atomic_wide_counter_fetch_xor_release (__atomic_wide_counter *c,
unsigned int val)
{
return atomic_fetch_xor_release (&c->__value64, val);
}
#else /* !__HAVE_64B_ATOMICS */
uint64_t __atomic_wide_counter_load_relaxed (__atomic_wide_counter *c)
attribute_hidden;
uint64_t __atomic_wide_counter_fetch_add_relaxed (__atomic_wide_counter *c,
unsigned int op)
attribute_hidden;
static inline uint64_t
__atomic_wide_counter_fetch_add_acquire (__atomic_wide_counter *c,
unsigned int val)
{
uint64_t r = __atomic_wide_counter_fetch_add_relaxed (c, val);
atomic_thread_fence_acquire ();
return r;
}
static inline void
__atomic_wide_counter_add_relaxed (__atomic_wide_counter *c,
unsigned int val)
{
__atomic_wide_counter_fetch_add_relaxed (c, val);
}
#endif /* !__HAVE_64B_ATOMICS */
#endif /* _ATOMIC_WIDE_COUNTER_H */

1
include/bits/atomic_wide_counter.h Normal file
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@ -0,0 +1 @@
#include_next <bits/atomic_wide_counter.h>

3
misc/Makefile
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@ -73,7 +73,8 @@ routines := brk sbrk sstk ioctl \
fgetxattr flistxattr fremovexattr fsetxattr getxattr \
listxattr lgetxattr llistxattr lremovexattr lsetxattr \
removexattr setxattr getauxval ifunc-impl-list makedev \
allocate_once fd_to_filename single_threaded unwind-link
allocate_once fd_to_filename single_threaded unwind-link \
atomic_wide_counter
generated += tst-error1.mtrace tst-error1-mem.out \
tst-allocate_once.mtrace tst-allocate_once-mem.out

127
misc/atomic_wide_counter.c Normal file
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@ -0,0 +1,127 @@
/* Monotonically increasing wide counters (at least 62 bits).
Copyright (C) 2016-2021 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
<https://www.gnu.org/licenses/>. */
#include <atomic_wide_counter.h>
#if !__HAVE_64B_ATOMICS
/* Values we add or xor are less than or equal to 1<<31, so we only
have to make overflow-and-addition atomic wrt. to concurrent load
operations and xor operations. To do that, we split each counter
into two 32b values of which we reserve the MSB of each to
represent an overflow from the lower-order half to the higher-order
half.
In the common case, the state is (higher-order / lower-order half, and . is
basically concatenation of the bits):
0.h / 0.l = h.l
When we add a value of x that overflows (i.e., 0.l + x == 1.L), we run the
following steps S1-S4 (the values these represent are on the right-hand
side):
S1: 0.h / 1.L == (h+1).L
S2: 1.(h+1) / 1.L == (h+1).L
S3: 1.(h+1) / 0.L == (h+1).L
S4: 0.(h+1) / 0.L == (h+1).L
If the LSB of the higher-order half is set, readers will ignore the
overflow bit in the lower-order half.
To get an atomic snapshot in load operations, we exploit that the
higher-order half is monotonically increasing; if we load a value V from
it, then read the lower-order half, and then read the higher-order half
again and see the same value V, we know that both halves have existed in
the sequence of values the full counter had. This is similar to the
validated reads in the time-based STMs in GCC's libitm (e.g.,
method_ml_wt).
One benefit of this scheme is that this makes load operations
obstruction-free because unlike if we would just lock the counter, readers
can almost always interpret a snapshot of each halves. Readers can be
forced to read a new snapshot when the read is concurrent with an overflow.
However, overflows will happen infrequently, so load operations are
practically lock-free. */
uint64_t
__atomic_wide_counter_fetch_add_relaxed (__atomic_wide_counter *c,
unsigned int op)
{
/* S1. Note that this is an atomic read-modify-write so it extends the
release sequence of release MO store at S3. */
unsigned int l = atomic_fetch_add_relaxed (&c->__value32.__low, op);
unsigned int h = atomic_load_relaxed (&c->__value32.__high);
uint64_t result = ((uint64_t) h << 31) | l;
l += op;
if ((l >> 31) > 0)
{
/* Overflow. Need to increment higher-order half. Note that all
add operations are ordered in happens-before. */
h++;
/* S2. Release MO to synchronize with the loads of the higher-order half
in the load operation. See __condvar_load_64_relaxed. */
atomic_store_release (&c->__value32.__high,
h | ((unsigned int) 1 << 31));
l ^= (unsigned int) 1 << 31;
/* S3. See __condvar_load_64_relaxed. */
atomic_store_release (&c->__value32.__low, l);
/* S4. Likewise. */
atomic_store_release (&c->__value32.__high, h);
}
return result;
}
uint64_t
__atomic_wide_counter_load_relaxed (__atomic_wide_counter *c)
{
unsigned int h, l, h2;
do
{
/* This load and the second one below to the same location read from the
stores in the overflow handling of the add operation or the
initializing stores (which is a simple special case because
initialization always completely happens before further use).
Because no two stores to the higher-order half write the same value,
the loop ensures that if we continue to use the snapshot, this load
and the second one read from the same store operation. All candidate
store operations have release MO.
If we read from S2 in the first load, then we will see the value of
S1 on the next load (because we synchronize with S2), or a value
later in modification order. We correctly ignore the lower-half's
overflow bit in this case. If we read from S4, then we will see the
value of S3 in the next load (or a later value), which does not have
the overflow bit set anymore.
*/
h = atomic_load_acquire (&c->__value32.__high);
/* This will read from the release sequence of S3 (i.e, either the S3
store or the read-modify-writes at S1 following S3 in modification
order). Thus, the read synchronizes with S3, and the following load
of the higher-order half will read from the matching S2 (or a later
value).
Thus, if we read a lower-half value here that already overflowed and
belongs to an increased higher-order half value, we will see the
latter and h and h2 will not be equal. */
l = atomic_load_acquire (&c->__value32.__low);
/* See above. */
h2 = atomic_load_relaxed (&c->__value32.__high);
}
while (h != h2);
if (((l >> 31) > 0) && ((h >> 31) > 0))
l ^= (unsigned int) 1 << 31;
return ((uint64_t) (h & ~((unsigned int) 1 << 31)) << 31) + l;
}
#endif /* !__HAVE_64B_ATOMICS */

13
nptl/Makefile
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@ -22,8 +22,14 @@ subdir := nptl
include ../Makeconfig
headers := pthread.h semaphore.h bits/semaphore.h \
bits/struct_mutex.h bits/struct_rwlock.h
headers := \
bits/atomic_wide_counter.h \
bits/semaphore.h \
bits/struct_mutex.h \
bits/struct_rwlock.h \
pthread.h \
semaphore.h \
# headers
extra-libs := libpthread
extra-libs-others := $(extra-libs)
@ -270,7 +276,7 @@ tests = tst-attr2 tst-attr3 tst-default-attr \
tst-mutexpi1 tst-mutexpi2 tst-mutexpi3 tst-mutexpi4 \
tst-mutexpi5 tst-mutexpi5a tst-mutexpi6 tst-mutexpi7 tst-mutexpi7a \
tst-mutexpi9 tst-mutexpi10 \
tst-cond22 tst-cond26 \
tst-cond26 \
tst-robustpi1 tst-robustpi2 tst-robustpi3 tst-robustpi4 tst-robustpi5 \
tst-robustpi6 tst-robustpi7 tst-robustpi9 \
tst-rwlock2 tst-rwlock2a tst-rwlock2b tst-rwlock3 \
@ -319,6 +325,7 @@ tests-internal := tst-robustpi8 tst-rwlock19 tst-rwlock20 \
tst-barrier5 tst-signal7 tst-mutex8 tst-mutex8-static \
tst-mutexpi8 tst-mutexpi8-static \
tst-setgetname \
tst-cond22 \
xtests = tst-setuid1 tst-setuid1-static tst-setuid2 \
tst-mutexpp1 tst-mutexpp6 tst-mutexpp10 tst-setgroups \

224
nptl/pthread_cond_common.c
View File

@ -17,79 +17,52 @@
<https://www.gnu.org/licenses/>. */
#include <atomic.h>
#include <atomic_wide_counter.h>
#include <stdint.h>
#include <pthread.h>
/* We need 3 least-significant bits on __wrefs for something else. */
/* We need 3 least-significant bits on __wrefs for something else.
This also matches __atomic_wide_counter requirements: The highest
value we add is __PTHREAD_COND_MAX_GROUP_SIZE << 2 to __g1_start
(the two extra bits are for the lock in the two LSBs of
__g1_start). */
#define __PTHREAD_COND_MAX_GROUP_SIZE ((unsigned) 1 << 29)
static inline uint64_t
__condvar_load_wseq_relaxed (pthread_cond_t *cond)
{
return __atomic_wide_counter_load_relaxed (&cond->__data.__wseq);
}
static inline uint64_t
__condvar_fetch_add_wseq_acquire (pthread_cond_t *cond, unsigned int val)
{
return __atomic_wide_counter_fetch_add_acquire (&cond->__data.__wseq, val);
}
static inline uint64_t
__condvar_load_g1_start_relaxed (pthread_cond_t *cond)
{
return __atomic_wide_counter_load_relaxed (&cond->__data.__g1_start);
}
static inline void
__condvar_add_g1_start_relaxed (pthread_cond_t *cond, unsigned int val)
{
__atomic_wide_counter_add_relaxed (&cond->__data.__g1_start, val);
}
#if __HAVE_64B_ATOMICS == 1
static uint64_t __attribute__ ((unused))
__condvar_load_wseq_relaxed (pthread_cond_t *cond)
{
return atomic_load_relaxed (&cond->__data.__wseq);
}
static uint64_t __attribute__ ((unused))
__condvar_fetch_add_wseq_acquire (pthread_cond_t *cond, unsigned int val)
{
return atomic_fetch_add_acquire (&cond->__data.__wseq, val);
}
static uint64_t __attribute__ ((unused))
static inline uint64_t
__condvar_fetch_xor_wseq_release (pthread_cond_t *cond, unsigned int val)
{
return atomic_fetch_xor_release (&cond->__data.__wseq, val);
return atomic_fetch_xor_release (&cond->__data.__wseq.__value64, val);
}
static uint64_t __attribute__ ((unused))
__condvar_load_g1_start_relaxed (pthread_cond_t *cond)
{
return atomic_load_relaxed (&cond->__data.__g1_start);
}
#else /* !__HAVE_64B_ATOMICS */
static void __attribute__ ((unused))
__condvar_add_g1_start_relaxed (pthread_cond_t *cond, unsigned int val)
{
atomic_store_relaxed (&cond->__data.__g1_start,
atomic_load_relaxed (&cond->__data.__g1_start) + val);
}
#else
/* We use two 64b counters: __wseq and __g1_start. They are monotonically
increasing and single-writer-multiple-readers counters, so we can implement
load, fetch-and-add, and fetch-and-xor operations even when we just have
32b atomics. Values we add or xor are less than or equal to 1<<31 (*),
so we only have to make overflow-and-addition atomic wrt. to concurrent
load operations and xor operations. To do that, we split each counter into
two 32b values of which we reserve the MSB of each to represent an
overflow from the lower-order half to the higher-order half.
In the common case, the state is (higher-order / lower-order half, and . is
basically concatenation of the bits):
0.h / 0.l = h.l
When we add a value of x that overflows (i.e., 0.l + x == 1.L), we run the
following steps S1-S4 (the values these represent are on the right-hand
side):
S1: 0.h / 1.L == (h+1).L
S2: 1.(h+1) / 1.L == (h+1).L
S3: 1.(h+1) / 0.L == (h+1).L
S4: 0.(h+1) / 0.L == (h+1).L
If the LSB of the higher-order half is set, readers will ignore the
overflow bit in the lower-order half.
To get an atomic snapshot in load operations, we exploit that the
higher-order half is monotonically increasing; if we load a value V from
it, then read the lower-order half, and then read the higher-order half
again and see the same value V, we know that both halves have existed in
the sequence of values the full counter had. This is similar to the
validated reads in the time-based STMs in GCC's libitm (e.g.,
method_ml_wt).
The xor operation needs to be an atomic read-modify-write. The write
/* The xor operation needs to be an atomic read-modify-write. The write
itself is not an issue as it affects just the lower-order half but not bits
used in the add operation. To make the full fetch-and-xor atomic, we
exploit that concurrently, the value can increase by at most 1<<31 (*): The
@ -97,117 +70,18 @@ __condvar_add_g1_start_relaxed (pthread_cond_t *cond, unsigned int val)
than __PTHREAD_COND_MAX_GROUP_SIZE waiters can enter concurrently and thus
increment __wseq. Therefore, if the xor operation observes a value of
__wseq, then the value it applies the modification to later on can be
derived (see below).
One benefit of this scheme is that this makes load operations
obstruction-free because unlike if we would just lock the counter, readers
can almost always interpret a snapshot of each halves. Readers can be
forced to read a new snapshot when the read is concurrent with an overflow.
However, overflows will happen infrequently, so load operations are
practically lock-free.
(*) The highest value we add is __PTHREAD_COND_MAX_GROUP_SIZE << 2 to
__g1_start (the two extra bits are for the lock in the two LSBs of
__g1_start). */
typedef struct
{
unsigned int low;
unsigned int high;
} _condvar_lohi;
static uint64_t
__condvar_fetch_add_64_relaxed (_condvar_lohi *lh, unsigned int op)
{
/* S1. Note that this is an atomic read-modify-write so it extends the
release sequence of release MO store at S3. */
unsigned int l = atomic_fetch_add_relaxed (&lh->low, op);
unsigned int h = atomic_load_relaxed (&lh->high);
uint64_t result = ((uint64_t) h << 31) | l;
l += op;
if ((l >> 31) > 0)
{
/* Overflow. Need to increment higher-order half. Note that all
add operations are ordered in happens-before. */
h++;
/* S2. Release MO to synchronize with the loads of the higher-order half
in the load operation. See __condvar_load_64_relaxed. */
atomic_store_release (&lh->high, h | ((unsigned int) 1 << 31));
l ^= (unsigned int) 1 << 31;
/* S3. See __condvar_load_64_relaxed. */
atomic_store_release (&lh->low, l);
/* S4. Likewise. */
atomic_store_release (&lh->high, h);
}
return result;
}
static uint64_t
__condvar_load_64_relaxed (_condvar_lohi *lh)
{
unsigned int h, l, h2;
do
{
/* This load and the second one below to the same location read from the
stores in the overflow handling of the add operation or the
initializing stores (which is a simple special case because
initialization always completely happens before further use).
Because no two stores to the higher-order half write the same value,
the loop ensures that if we continue to use the snapshot, this load
and the second one read from the same store operation. All candidate
store operations have release MO.
If we read from S2 in the first load, then we will see the value of
S1 on the next load (because we synchronize with S2), or a value
later in modification order. We correctly ignore the lower-half's
overflow bit in this case. If we read from S4, then we will see the
value of S3 in the next load (or a later value), which does not have
the overflow bit set anymore.
*/
h = atomic_load_acquire (&lh->high);
/* This will read from the release sequence of S3 (i.e, either the S3
store or the read-modify-writes at S1 following S3 in modification
order). Thus, the read synchronizes with S3, and the following load
of the higher-order half will read from the matching S2 (or a later
value).
Thus, if we read a lower-half value here that already overflowed and
belongs to an increased higher-order half value, we will see the
latter and h and h2 will not be equal. */
l = atomic_load_acquire (&lh->low);
/* See above. */
h2 = atomic_load_relaxed (&lh->high);
}
while (h != h2);
if (((l >> 31) > 0) && ((h >> 31) > 0))
l ^= (unsigned int) 1 << 31;
return ((uint64_t) (h & ~((unsigned int) 1 << 31)) << 31) + l;
}
static uint64_t __attribute__ ((unused))
__condvar_load_wseq_relaxed (pthread_cond_t *cond)
{
return __condvar_load_64_relaxed ((_condvar_lohi *) &cond->__data.__wseq32);
}
static uint64_t __attribute__ ((unused))
__condvar_fetch_add_wseq_acquire (pthread_cond_t *cond, unsigned int val)
{
uint64_t r = __condvar_fetch_add_64_relaxed
((_condvar_lohi *) &cond->__data.__wseq32, val);
atomic_thread_fence_acquire ();
return r;
}
derived. */
static uint64_t __attribute__ ((unused))
__condvar_fetch_xor_wseq_release (pthread_cond_t *cond, unsigned int val)
{
_condvar_lohi *lh = (_condvar_lohi *) &cond->__data.__wseq32;
/* First, get the current value. See __condvar_load_64_relaxed. */
unsigned int h, l, h2;
do
{
h = atomic_load_acquire (&lh->high);
l = atomic_load_acquire (&lh->low);
h2 = atomic_load_relaxed (&lh->high);
h = atomic_load_acquire (&cond->__data.__wseq.__value32.__high);
l = atomic_load_acquire (&cond->__data.__wseq.__value32.__low);
h2 = atomic_load_relaxed (&cond->__data.__wseq.__value32.__high);
}
while (h != h2);
if (((l >> 31) > 0) && ((h >> 31) == 0))
@ -219,8 +93,9 @@ __condvar_fetch_xor_wseq_release (pthread_cond_t *cond, unsigned int val)
earlier in modification order than the following fetch-xor.
This uses release MO to make the full operation have release semantics
(all other operations access the lower-order half). */
unsigned int l2 = atomic_fetch_xor_release (&lh->low, val)
& ~((unsigned int) 1 << 31);
unsigned int l2
= (atomic_fetch_xor_release (&cond->__data.__wseq.__value32.__low, val)
& ~((unsigned int) 1 << 31));
if (l2 < l)
/* The lower-order half overflowed in the meantime. This happened exactly
once due to the limit on concurrent waiters (see above). */
@ -228,22 +103,7 @@ __condvar_fetch_xor_wseq_release (pthread_cond_t *cond, unsigned int val)
return ((uint64_t) h << 31) + l2;
}
static uint64_t __attribute__ ((unused))
__condvar_load_g1_start_relaxed (pthread_cond_t *cond)
{
return __condvar_load_64_relaxed
((_condvar_lohi *) &cond->__data.__g1_start32);
}
static void __attribute__ ((unused))
__condvar_add_g1_start_relaxed (pthread_cond_t *cond, unsigned int val)
{
ignore_value (__condvar_fetch_add_64_relaxed
((_condvar_lohi *) &cond->__data.__g1_start32, val));
}
#endif /* !__HAVE_64B_ATOMICS */
#endif /* !__HAVE_64B_ATOMICS */
/* The lock that signalers use. See pthread_cond_wait_common for uses.
The lock is our normal three-state lock: not acquired (0) / acquired (1) /

14
nptl/tst-cond22.c
View File

@ -106,8 +106,11 @@ do_test (void)
status = 1;
}
printf ("cond = { %llu, %llu, %u/%u/%u, %u/%u/%u, %u, %u }\n",
c.__data.__wseq, c.__data.__g1_start,
printf ("cond = { 0x%x:%x, 0x%x:%x, %u/%u/%u, %u/%u/%u, %u, %u }\n",
c.__data.__wseq.__value32.__high,
c.__data.__wseq.__value32.__low,
c.__data.__g1_start.__value32.__high,
c.__data.__g1_start.__value32.__low,
c.__data.__g_signals[0], c.__data.__g_refs[0], c.__data.__g_size[0],
c.__data.__g_signals[1], c.__data.__g_refs[1], c.__data.__g_size[1],
c.__data.__g1_orig_size, c.__data.__wrefs);
@ -149,8 +152,11 @@ do_test (void)
status = 1;
}
printf ("cond = { %llu, %llu, %u/%u/%u, %u/%u/%u, %u, %u }\n",
c.__data.__wseq, c.__data.__g1_start,
printf ("cond = { 0x%x:%x, 0x%x:%x, %u/%u/%u, %u/%u/%u, %u, %u }\n",
c.__data.__wseq.__value32.__high,
c.__data.__wseq.__value32.__low,
c.__data.__g1_start.__value32.__high,
c.__data.__g1_start.__value32.__low,
c.__data.__g_signals[0], c.__data.__g_refs[0], c.__data.__g_size[0],
c.__data.__g_signals[1], c.__data.__g_refs[1], c.__data.__g_size[1],
c.__data.__g1_orig_size, c.__data.__wrefs);

22
sysdeps/nptl/bits/thread-shared-types.h
View File

@ -43,6 +43,8 @@
#include <bits/pthreadtypes-arch.h>
#include <bits/atomic_wide_counter.h>
/* Common definition of pthread_mutex_t. */
@ -91,24 +93,8 @@ typedef struct __pthread_internal_slist
struct __pthread_cond_s
{
__extension__ union
{
__extension__ unsigned long long int __wseq;
struct
{
unsigned int __low;
unsigned int __high;
} __wseq32;
};
__extension__ union
{
__extension__ unsigned long long int __g1_start;
struct
{
unsigned int __low;
unsigned int __high;
} __g1_start32;
};
__atomic_wide_counter __wseq;
__atomic_wide_counter __g1_start;
unsigned int __g_refs[2] __LOCK_ALIGNMENT;
unsigned int __g_size[2];
unsigned int __g1_orig_size;