From: Lukasz Majewski <lukma@denx.de>
To: Joseph Myers <joseph@codesourcery.com>,
Paul Eggert <eggert@cs.ucla.edu>,
Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: Florian Weimer <fweimer@redhat.com>,
Stefan Liebler <stli@linux.ibm.com>,
GNU C Library <libc-alpha@sourceware.org>,
Andreas Schwab <schwab@suse.de>,
Stepan Golosunov <stepan@golosunov.pp.ru>,
Alistair Francis <alistair.francis@wdc.com>
Subject: [PATCH] y2038: nptl: Provide __futex_clock_wait_bitset64 to support 64 bit bitset
Date: Mon, 19 Oct 2020 16:57:39 +0200 [thread overview]
Message-ID: <20201019145739.32361-1-lukma@denx.de> (raw)
The commit:
"y2038: nptl: Convert pthread_mutex_{clock|timed}lock to support 64 bit"
SHA1: 29e9874a048f47e2d46c40253036c8d2de921548
introduced support for 64 bit timeouts. Unfortunately, it was missing the
code for bitset - i.e. lll_futex_clock_wait_bitset C preprocessor macro
was used. As a result the 64 bit struct __timespec64 was coerced to 32
bit struct timespec and regression visible as timeout was observed
(nptl/tst-robust10 on s390).
Reported-by: Stefan Liebler <stli@linux.ibm.com>
---
nptl/pthread_mutex_timedlock.c | 2 +-
sysdeps/nptl/futex-internal.c | 48 +++++++++++++++++++++++++++++++++-
sysdeps/nptl/futex-internal.h | 5 ++++
3 files changed, 53 insertions(+), 2 deletions(-)
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c
index dc40399f02..fe9e651f6c 100644
--- a/nptl/pthread_mutex_timedlock.c
+++ b/nptl/pthread_mutex_timedlock.c
@@ -268,7 +268,7 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
assume_other_futex_waiters |= FUTEX_WAITERS;
/* Block using the futex. */
- int err = lll_futex_clock_wait_bitset (&mutex->__data.__lock,
+ int err = __futex_clock_wait_bitset64 (&mutex->__data.__lock,
oldval, clockid, abstime,
PTHREAD_ROBUST_MUTEX_PSHARED (mutex));
/* The futex call timed out. */
diff --git a/sysdeps/nptl/futex-internal.c b/sysdeps/nptl/futex-internal.c
index 2e1919f056..a978ad0ad2 100644
--- a/sysdeps/nptl/futex-internal.c
+++ b/sysdeps/nptl/futex-internal.c
@@ -70,7 +70,28 @@ __futex_abstimed_wait32 (unsigned int* futex_word,
abstime != NULL ? &ts32 : NULL,
NULL /* Unused. */, FUTEX_BITSET_MATCH_ANY);
}
-#endif
+
+static int
+__futex_clock_wait_bitset32 (int *futexp, int val, clockid_t clockid,
+ const struct __timespec64 *abstime, int private)
+{
+ struct timespec ts32;
+
+ if (abstime != NULL && ! in_time_t_range (abstime->tv_sec))
+ return -EOVERFLOW;
+
+ const unsigned int clockbit =
+ (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0;
+ const int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, private);
+
+ if (abstime != NULL)
+ ts32 = valid_timespec64_to_timespec (*abstime);
+
+ return INTERNAL_SYSCALL_CALL (futex, futexp, op, val,
+ abstime != NULL ? &ts32 : NULL,
+ NULL /* Unused. */, FUTEX_BITSET_MATCH_ANY);
+}
+#endif /* ! __ASSUME_TIME64_SYSCALLS */
int
__futex_abstimed_wait_cancelable64 (unsigned int* futex_word,
@@ -222,3 +243,28 @@ __futex_clocklock_wait64 (int *futex, int val, clockid_t clockid,
return -err;
}
+
+int
+__futex_clock_wait_bitset64 (int *futexp, int val, clockid_t clockid,
+ const struct __timespec64 *abstime,
+ int private)
+{
+ long int ret;
+ if (! lll_futex_supported_clockid (clockid))
+ {
+ return -EINVAL;
+ }
+
+ const unsigned int clockbit =
+ (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0;
+ const int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, private);
+
+ ret = INTERNAL_SYSCALL_CALL (futex_time64, futexp, op, val,
+ abstime, NULL /* Unused. */,
+ FUTEX_BITSET_MATCH_ANY);
+#ifndef __ASSUME_TIME64_SYSCALLS
+ if (ret == -ENOSYS)
+ ret = __futex_clock_wait_bitset32 (futexp, val, clockid, abstime, private);
+#endif
+ return ret;
+}
diff --git a/sysdeps/nptl/futex-internal.h b/sysdeps/nptl/futex-internal.h
index 8a5f62768f..cd356e4fa8 100644
--- a/sysdeps/nptl/futex-internal.h
+++ b/sysdeps/nptl/futex-internal.h
@@ -603,4 +603,9 @@ __futex_clocklock64 (int *futex, clockid_t clockid,
return err;
}
+int
+__futex_clock_wait_bitset64 (int *futexp, int val, clockid_t clockid,
+ const struct __timespec64 *abstime,
+ int private) attribute_hidden;
+
#endif /* futex-internal.h */
--
2.20.1
next reply other threads:[~2020-10-19 14:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-19 14:57 Lukasz Majewski [this message]
2020-10-20 11:01 ` [PATCH] y2038: nptl: Provide __futex_clock_wait_bitset64 to support 64 bit bitset Stefan Liebler via Libc-alpha
2020-10-20 13:31 ` Lukasz Majewski
2020-10-21 6:49 ` Stefan Liebler via Libc-alpha
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