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y2038: nptl: Convert pthread_mutex_{clock|timed}lock to support 64 bit

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The pthread_mutex_clocklock and pthread_mutex_timedlock have been converted
to support 64 bit time.

This change uses:
- New __futex_clocklock_wait64 (instead of lll_timedwait)

from ./sysdeps/nptl/futex-helpers.c and

- New __futex_clocklock64 function (instead of lll_clocklock)
- New futex_lock_pi64

defined in sysdeps/nptl/futex-internal.h

The pthread_mutex_{clock|timed}lock only accepts absolute time.
Moreover, there is no need to check for NULL passed as *abstime pointer to the
syscalls as those calls have exported symbols marked with __nonull attribute
for abstime.

Some architectures - namely x86, powerpc and s390 - do support lock elision.
For those - adjustments have been made in arch specific elision-*.c files
to use __futex_clocklock64 instead of lll_clocklock.
The __lll_lock_elision (aliased to __lll_clocklock_elision in e.g.
sysdeps/unix/sysv/linux/s390/elision-timed.c) just uses, in this patch
provided, __futex_clocklock64.

For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to pthread_mutex_{clock|timed}lock will provide support for 64
bit time

Build tests:
./src/scripts/build-many-glibcs.py glibcs

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
This commit is contained in:
Lukasz Majewski 2020-09-18 20:54:13 +02:00
parent 9ebaabeaac
commit 29e9874a04
10 changed files with 190 additions and 31 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
nptl/pthreadP.h
View file

@ -468,6 +468,8 @@ extern int __pthread_cond_wait (pthread_cond_t *cond, pthread_mutex_t *mutex);
# define __pthread_rwlock_clockwrlock64 __pthread_rwlock_clockwrlock
# define __pthread_rwlock_timedrdlock64 __pthread_rwlock_timedrdlock
# define __pthread_rwlock_timedwrlock64 __pthread_rwlock_timedwrlock
# define __pthread_mutex_clocklock64 __pthread_mutex_clocklock
# define __pthread_mutex_timedlock64 __pthread_mutex_timedlock
#else
extern int __pthread_clockjoin_np64 (pthread_t threadid, void **thread_return,
clockid_t clockid,
@ -499,6 +501,13 @@ libpthread_hidden_proto (__pthread_rwlock_timedrdlock64)
extern int __pthread_rwlock_timedwrlock64 (pthread_rwlock_t *rwlock,
const struct __timespec64 *abstime);
libpthread_hidden_proto (__pthread_rwlock_timedwrlock64)
extern int __pthread_mutex_clocklock64 (pthread_mutex_t *mutex,
clockid_t clockid,
const struct __timespec64 *abstime);
libpthread_hidden_proto (__pthread_mutex_clocklock64)
extern int __pthread_mutex_timedlock64 (pthread_mutex_t *mutex,
const struct __timespec64 *abstime);
libpthread_hidden_proto (__pthread_mutex_timedlock64)
#endif
extern int __pthread_cond_timedwait (pthread_cond_t *cond,

66
nptl/pthread_mutex_timedlock.c
View file

@ -31,7 +31,7 @@
#ifndef lll_clocklock_elision
#define lll_clocklock_elision(futex, adapt_count, clockid, abstime, private) \
lll_clocklock (futex, clockid, abstime, private)
__futex_clocklock64 (&(futex), clockid, abstime, private)
#endif
#ifndef lll_trylock_elision
@ -45,7 +45,7 @@
int
__pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
clockid_t clockid,
const struct timespec *abstime)
const struct __timespec64 *abstime)
{
int oldval;
pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
@ -76,8 +76,8 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
}
/* We have to get the mutex. */
result = lll_clocklock (mutex->__data.__lock, clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
result = __futex_clocklock64 (&mutex->__data.__lock, clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
if (result != 0)
goto out;
@ -99,8 +99,8 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
FORCE_ELISION (mutex, goto elision);
simple:
/* Normal mutex. */
result = lll_clocklock (mutex->__data.__lock, clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
result = __futex_clocklock64 (&mutex->__data.__lock, clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
break;
case PTHREAD_MUTEX_TIMED_ELISION_NP:
@ -125,9 +125,9 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
{
if (cnt++ >= max_cnt)
{
result = lll_clocklock (mutex->__data.__lock,
clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
result = __futex_clocklock64 (&mutex->__data.__lock,
clockid, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
break;
}
atomic_spin_nop ();
@ -378,8 +378,7 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
int private = (robust
? PTHREAD_ROBUST_MUTEX_PSHARED (mutex)
: PTHREAD_MUTEX_PSHARED (mutex));
int e = futex_lock_pi ((unsigned int *) &mutex->__data.__lock,
abstime, private);
int e = futex_lock_pi64 (&mutex->__data.__lock, abstime, private);
if (e == ETIMEDOUT)
return ETIMEDOUT;
else if (e == ESRCH || e == EDEADLK)
@ -394,8 +393,8 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
/* Delay the thread until the timeout is reached. Then return
ETIMEDOUT. */
do
e = lll_timedwait (&(int){0}, 0, clockid, abstime,
private);
e = __futex_clocklock_wait64 (&(int){0}, 0, clockid, abstime,
private);
while (e != ETIMEDOUT);
return ETIMEDOUT;
}
@ -543,10 +542,10 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
goto failpp;
}
struct timespec rt;
struct __timespec64 rt;
/* Get the current time. */
__clock_gettime (CLOCK_REALTIME, &rt);
__clock_gettime64 (CLOCK_REALTIME, &rt);
/* Compute relative timeout. */
rt.tv_sec = abstime->tv_sec - rt.tv_sec;
@ -599,9 +598,9 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
}
int
__pthread_mutex_clocklock (pthread_mutex_t *mutex,
clockid_t clockid,
const struct timespec *abstime)
__pthread_mutex_clocklock64 (pthread_mutex_t *mutex,
clockid_t clockid,
const struct __timespec64 *abstime)
{
if (__glibc_unlikely (!lll_futex_supported_clockid (clockid)))
return EINVAL;
@ -609,13 +608,40 @@ __pthread_mutex_clocklock (pthread_mutex_t *mutex,
LIBC_PROBE (mutex_clocklock_entry, 3, mutex, clockid, abstime);
return __pthread_mutex_clocklock_common (mutex, clockid, abstime);
}
#if __TIMESIZE != 64
libpthread_hidden_def (__pthread_mutex_clocklock64)
int
__pthread_mutex_clocklock (pthread_mutex_t *mutex,
clockid_t clockid,
const struct timespec *abstime)
{
struct __timespec64 ts64 = valid_timespec_to_timespec64 (*abstime);
return __pthread_mutex_clocklock64 (mutex, clockid, &ts64);
}
#endif
weak_alias (__pthread_mutex_clocklock, pthread_mutex_clocklock)
int
__pthread_mutex_timedlock64 (pthread_mutex_t *mutex,
const struct __timespec64 *abstime)
{
LIBC_PROBE (mutex_timedlock_entry, 2, mutex, abstime);
return __pthread_mutex_clocklock_common (mutex, CLOCK_REALTIME, abstime);
}
#if __TIMESIZE != 64
libpthread_hidden_def (__pthread_mutex_timedlock64)
int
__pthread_mutex_timedlock (pthread_mutex_t *mutex,
const struct timespec *abstime)
{
LIBC_PROBE (mutex_timedlock_entry, 2, mutex, abstime);
return __pthread_mutex_clocklock_common (mutex, CLOCK_REALTIME, abstime);
struct __timespec64 ts64 = valid_timespec_to_timespec64 (*abstime);
return __pthread_mutex_timedlock64 (mutex, &ts64);
}
#endif
weak_alias (__pthread_mutex_timedlock, pthread_mutex_timedlock)

53
sysdeps/nptl/futex-internal.c
View file

@ -169,3 +169,56 @@ __futex_abstimed_wait64 (unsigned int* futex_word, unsigned int expected,
futex_fatal_error ();
}
}
int
__futex_clocklock_wait64 (int *futex, int val, clockid_t clockid,
const struct __timespec64 *abstime, int private)
{
struct __timespec64 ts, *tsp = NULL;
if (abstime != NULL)
{
/* Reject invalid timeouts. */
if (! valid_nanoseconds (abstime->tv_nsec))
return EINVAL;
/* Get the current time. This can only fail if clockid is not valid. */
if (__glibc_unlikely (__clock_gettime64 (clockid, &ts) != 0))
return EINVAL;
/* Compute relative timeout. */
ts.tv_sec = abstime->tv_sec - ts.tv_sec;
ts.tv_nsec = abstime->tv_nsec - ts.tv_nsec;
if (ts.tv_nsec < 0)
{
ts.tv_nsec += 1000000000;
--ts.tv_sec;
}
if (ts.tv_sec < 0)
return ETIMEDOUT;
tsp = &ts;
}
int err = INTERNAL_SYSCALL_CALL (futex_time64, futex,
__lll_private_flag (FUTEX_WAIT, private),
val, tsp);
#ifndef __ASSUME_TIME64_SYSCALLS
if (err == -ENOSYS)
{
if (tsp != NULL && ! in_time_t_range (tsp->tv_sec))
return EOVERFLOW;
struct timespec ts32;
if (tsp != NULL)
ts32 = valid_timespec64_to_timespec (*tsp);
err = INTERNAL_SYSCALL_CALL (futex, futex,
__lll_private_flag (FUTEX_WAIT, private),
val, tsp != NULL ? &ts32 : NULL);
}
#endif
return -err;
}

72
sysdeps/nptl/futex-internal.h
View file

@ -437,6 +437,51 @@ futex_lock_pi (unsigned int *futex_word, const struct timespec *abstime,
}
}
static __always_inline int
futex_lock_pi64 (int *futex_word, const struct __timespec64 *abstime,
int private)
{
int err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word,
__lll_private_flag
(FUTEX_LOCK_PI, private), 0, abstime);
#ifndef __ASSUME_TIME64_SYSCALLS
if (err == -ENOSYS)
{
if (abstime != NULL && ! in_time_t_range (abstime->tv_sec))
return EOVERFLOW;
struct timespec ts32;
if (abstime != NULL)
ts32 = valid_timespec64_to_timespec (*abstime);
err = INTERNAL_SYSCALL_CALL (futex, futex_word, __lll_private_flag
(FUTEX_LOCK_PI, private), 0,
abstime != NULL ? &ts32 : NULL);
}
#endif
switch (err)
{
case 0:
case -EAGAIN:
case -EINTR:
case -ETIMEDOUT:
case -ESRCH:
case -EDEADLK:
case -EINVAL: /* This indicates either state corruption or that the kernel
found a waiter on futex address which is waiting via
FUTEX_WAIT or FUTEX_WAIT_BITSET. This is reported on
some futex_lock_pi usage (pthread_mutex_timedlock for
instance). */
return -err;
case -EFAULT: /* Must have been caused by a glibc or application bug. */
case -ENOSYS: /* Must have been caused by a glibc bug. */
/* No other errors are documented at this time. */
default:
futex_fatal_error ();
}
}
/* Wakes the top priority waiter that called a futex_lock_pi operation on
the futex.
@ -476,8 +521,8 @@ futex_timed_wait_cancel64 (pid_t *tidp, pid_t tid,
const struct __timespec64 *timeout, int private)
{
int err = INTERNAL_SYSCALL_CANCEL (futex_time64, tidp,
__lll_private_flag
(FUTEX_WAIT, private), tid, timeout);
__lll_private_flag (FUTEX_WAIT, private),
tid, timeout);
#ifndef __ASSUME_TIME64_SYSCALLS
if (err == -ENOSYS)
{
@ -535,4 +580,27 @@ __futex_abstimed_wait64 (unsigned int* futex_word, unsigned int expected,
const struct __timespec64* abstime,
int private) attribute_hidden;
int
__futex_clocklock_wait64 (int *futex, int val, clockid_t clockid,
const struct __timespec64 *abstime,
int private) attribute_hidden;
static __always_inline int
__futex_clocklock64 (int *futex, clockid_t clockid,
const struct __timespec64 *abstime, int private)
{
int err = 0;
if (__glibc_unlikely (atomic_compare_and_exchange_bool_acq (futex, 1, 0)))
{
while (atomic_exchange_acq (futex, 2) != 0)
{
err = __futex_clocklock_wait64 (futex, 2, clockid, abstime, private);
if (err == EINVAL || err == ETIMEDOUT || err == EOVERFLOW)
break;
}
}
return err;
}
#endif /* futex-internal.h */

5
sysdeps/unix/sysv/linux/powerpc/elision-timed.c
View file

@ -19,10 +19,11 @@
#include <time.h>
#include <elision-conf.h>
#include "lowlevellock.h"
#include "futex-internal.h"
#define __lll_lock_elision __lll_clocklock_elision
#define EXTRAARG clockid_t clockid, const struct timespec *t,
#define EXTRAARG clockid_t clockid, const struct __timespec64 *t,
#undef LLL_LOCK
#define LLL_LOCK(a, b) lll_clocklock(a, clockid, t, b)
#define LLL_LOCK(a, b) __futex_clocklock64 (&(a), clockid, t, b)
#include "elision-lock.c"

2
sysdeps/unix/sysv/linux/powerpc/lowlevellock.h
View file

@ -24,7 +24,7 @@
/* Transactional lock elision definitions. */
extern int __lll_clocklock_elision
(int *futex, short *adapt_count,
clockid_t clockid, const struct timespec *timeout, int private)
clockid_t clockid, const struct __timespec64 *timeout, int private)
attribute_hidden;
#define lll_clocklock_elision(futex, adapt_count, clockid, timeout, private) \

5
sysdeps/unix/sysv/linux/s390/elision-timed.c
View file

@ -19,8 +19,9 @@
#include <time.h>
#include <elision-conf.h>
#include <lowlevellock.h>
#include "futex-internal.h"
#define __lll_lock_elision __lll_clocklock_elision
#define EXTRAARG clockid_t clockid, const struct timespec *t,
#define EXTRAARG clockid_t clockid, const struct __timespec64 *t,
#undef LLL_LOCK
#define LLL_LOCK(a, b) lll_clocklock(a, clockid, t, b)
#define LLL_LOCK(a, b) __futex_clocklock64 (&(a), clockid, t, b)
#include "elision-lock.c"

2
sysdeps/unix/sysv/linux/s390/lowlevellock.h
View file

@ -24,7 +24,7 @@
/* Transactional lock elision definitions. */
extern int __lll_clocklock_elision
(int *futex, short *adapt_count,
clockid_t clockid, const struct timespec *timeout, int private)
clockid_t clockid, const struct __timespec64 *timeout, int private)
attribute_hidden;
# define lll_clocklock_elision(futex, adapt_count, clockid, timeout, private) \

5
sysdeps/unix/sysv/linux/x86/elision-timed.c
View file

@ -19,8 +19,9 @@
#include <time.h>
#include <elision-conf.h>
#include "lowlevellock.h"
#include "futex-internal.h"
#define __lll_lock_elision __lll_clocklock_elision
#define EXTRAARG clockid_t clockid, const struct timespec *t,
#define EXTRAARG clockid_t clockid, const struct __timespec64 *t,
#undef LLL_LOCK
#define LLL_LOCK(a, b) lll_clocklock (a, clockid, t, b)
#define LLL_LOCK(a, b) __futex_clocklock64 (&(a), clockid, t, b)
#include "elision-lock.c"

2
sysdeps/unix/sysv/linux/x86/lowlevellock.h
View file

@ -84,7 +84,7 @@ __lll_cas_lock (int *futex)
extern int __lll_clocklock_elision (int *futex, short *adapt_count,
clockid_t clockid,
const struct timespec *timeout,
const struct __timespec64 *timeout,
int private) attribute_hidden;
#define lll_clocklock_elision(futex, adapt_count, clockid, timeout, private) \