This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
[RFC][PATCH 1/3][BZ #11588] pi-condvars: add protocol support to pthread_condattr_t
- From: Gratian Crisan <gratian dot crisan at ni dot com>
- To: libc-alpha at sourceware dot org
- Cc: Darren Hart <dvhart at linux dot intel dot com>, "Carlos O'Donell" <carlos at redhat dot com>, Jeff Law <law at redhat dot com>, Scot Salmon <scot dot salmon at ni dot com>, Siddhesh Poyarekar <spoyarek at redhat dot com>, Thomas Gleixner <tglx at linutronix dot de>, Torvald Riegel <triegel at redhat dot com>, Clark Williams <williams at redhat dot com>
- Date: Thu, 17 Oct 2013 16:34:02 -0500
- Subject: [RFC][PATCH 1/3][BZ #11588] pi-condvars: add protocol support to pthread_condattr_t
- Authentication-results: sourceware.org; auth=none
When using a PTHREAD_PRIO_INHERIT mutex with a condvar, the pthread_cond*
calls
can still cause an unbounded priority inversion via the internal condvar
lock.
The POSIX specification doesn't provide a mechanism to specify the
protocol of
the condvar. We would like to do this at runtime, but unfortunately it is
legal
to call pthread_cond_signal() or pthread_cond_broadcast() without first
waiting
on the lock, so the mutex type may not be known the first time the condvar
is
used. A new API, pthread_condattr_setprotocol_np() and
pthread_condattr_getprotocol_np() allow the user to create a
PTHREAD_PRIO_INHERIT condvar. This uses a PTHREAD_PRIO_INHERIT mutex for
the
internal condvar lock, eliminating the potential for hitting an unbounded
priority inversion on that lock. A new flag was added to the value field
in
pthread_condattr and the corresponding __nwaiters field to represent the
cond
protocol attributes.
Signed-off-by: Dinakar Guniguntala <dino@in.ibm.com>
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
<Ported to glibc 2.19 by Gratian Crisan>
Signed-off-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
Changes since V1:
* Dropped the changes related to making the external mutex associated with
the
condvar PI-aware since they have been already committed.
* Moved lll_pi_lock()/lll_pi_unlock() to lowlevelpilock.c
* Changed the value bitmap in pthread_condattr to use only 1 bit for clock
ID
This matches the equivalent bitmap in the __nwaiters field.
ChangeLog:
2013-10-16 Gratian Crisan <gratian.crisan@ni.com>
[BZ #11588]
* Versions.def (libpthread): Add GLIBC_2.19.
* ports/sysdeps/unix/sysv/linux/arm/nptl/libpthread.abilist:
Update.
* sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist: Update.
* sysdeps/unix/sysv/linux/x86_64/64/nptl/libpthread.abilist:
Update.
nptl/ChangeLog:
2013-10-15 Gratian Crisan <gratian.crisan@ni.com>
Darren Hart <dvhart@linux.intel.com>
Dinakar Guniguntala <dino@in.ibm.com>
[BZ #11588]
* pthread_condattr_getprotocol_np.c: New file.
* pthread_condattr_setprotocol_np.c: New file.
* sysdeps/pthread/cond-lock.h: New file.
* sysdeps/unix/sysv/linux/lowlevelpilock.c: New file.
* sysdeps/pthread/pthread.h: Declare
pthread_condattr_getprotocol_np
and pthread_condattr_setprotocol_np.
* sysdeps/unix/sysv/linux/internaltypes.h: Define
CONDATTR_PSHARED_MASK, CONDATTR_CLOCKID_MASK,
CONDATTR_CLOCKID_SHIFT,
CONDATTR_PROTOCOL_MASK, CONDATTR_PROTOCOL_SHIFT,
COND_CLOCKID_MASK,
COND_PROTOCOL_SHIFT, COND_PROTOCOL_MASK, COND_PRIO_INHERIT and
COND_PRIO_PROTECT.
Change value of COND_NWAITERS_SHIFT to account for PI bits.
* pthread_cond_broadcast.c (__pthread_cond_broadcast): Use
cond_lock
and cond_unlock instead of lll_lock/lll_unlock for internal mutex.
* pthread_cond_destroy.c (__pthread_cond_destroy): Likewise.
* pthread_cond_signal.c (__pthread_cond_signal): Likewise.
* pthread_cond_wait.c (__condvar_cleanup): Likewise.
(__pthread_cond_wait): Likewise.
* pthread_cond_timedwait.c (__pthread_cond_timedwait): Likewise.
Use
COND_CLOCKID_MASK instead of COND_NWAITERS_SHIFT.
* pthread_condattr_getclock.c (pthread_condattr_getclock): Use
CONDATTR_CLOCKID_MASK and CONDATTR_CLOCKID_SHIFT instead of
COND_NWAITERS_SHIFT based math.
* pthread_condattr_setclock.c (pthread_condattr_setclock):
Likewise.
* pthread_cond_init.c (__pthread_cond_init): Likewise.
Set COND_PRIO_INHERIT or COND_PRIO_PROTECT bits.
* pthread_condattr_getpshared.c (pthread_condattr_getpshared): Use
CONDATTR_PSHARED_MASK instead of numeric constant.
* pthread_condattr_setpshared.c (pthread_condattr_setpshared):
Likewise.
* Makefile (libpthread-routines): Add
pthread_condattr_getprotocol_np, pthread_condattr_setprotocol_np
and
lowlevelpilock.
* Versions: Add pthread_condattr_getprotocol_np and
pthread_condattr_setprotocol_np for GLIBC_2.19
---
Versions.def | 1 +
nptl/Makefile | 3 +-
nptl/Versions | 5 ++
nptl/pthread_cond_broadcast.c | 7 +--
nptl/pthread_cond_destroy.c | 9 ++--
nptl/pthread_cond_init.c | 22 +++++++-
nptl/pthread_cond_signal.c | 7 +--
nptl/pthread_cond_timedwait.c | 15 +++---
nptl/pthread_cond_wait.c | 16 +++---
nptl/pthread_condattr_getclock.c | 5 +-
nptl/pthread_condattr_getprotocol_np.c | 30 +++++++++++
nptl/pthread_condattr_getpshared.c | 3 +-
nptl/pthread_condattr_setclock.c | 6 +--
nptl/pthread_condattr_setprotocol_np.c | 38 +++++++++++++
nptl/pthread_condattr_setpshared.c | 3 +-
nptl/sysdeps/pthread/cond-lock.h | 62
++++++++++++++++++++++
nptl/sysdeps/pthread/pthread.h | 12 +++++
nptl/sysdeps/unix/sysv/linux/internaltypes.h | 29 +++++++---
nptl/sysdeps/unix/sysv/linux/lowlevelpilock.c | 61
+++++++++++++++++++++
.../unix/sysv/linux/arm/nptl/libpthread.abilist | 4 ++
.../unix/sysv/linux/i386/nptl/libpthread.abilist | 4 ++
.../sysv/linux/x86_64/64/nptl/libpthread.abilist | 4 ++
22 files changed, 306 insertions(+), 40 deletions(-)
create mode 100644 nptl/pthread_condattr_getprotocol_np.c
create mode 100644 nptl/pthread_condattr_setprotocol_np.c
create mode 100644 nptl/sysdeps/pthread/cond-lock.h
create mode 100644 nptl/sysdeps/unix/sysv/linux/lowlevelpilock.c
diff --git a/Versions.def b/Versions.def
index bca4ff4..d6edb58 100644
--- a/Versions.def
+++ b/Versions.def
@@ -104,6 +104,7 @@ libpthread {
GLIBC_2.11
GLIBC_2.12
GLIBC_2.18
+ GLIBC_2.19
GLIBC_PRIVATE
}
libresolv {
diff --git a/nptl/Makefile b/nptl/Makefile
index cd601e5..46f8e9e 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -74,6 +74,7 @@ libpthread-routines = nptl-init vars events version \
old_pthread_cond_signal old_pthread_cond_broadcast \
pthread_condattr_init pthread_condattr_destroy \
pthread_condattr_getpshared
pthread_condattr_setpshared \
+ pthread_condattr_getprotocol_np
pthread_condattr_setprotocol_np \
pthread_condattr_getclock pthread_condattr_setclock
\
pthread_spin_init pthread_spin_destroy \
pthread_spin_lock pthread_spin_trylock \
@@ -100,7 +101,7 @@ libpthread-routines = nptl-init vars events version \
cleanup_defer_compat unwind \
pt-longjmp pt-cleanup\
cancellation \
- lowlevellock lowlevelrobustlock \
+ lowlevellock lowlevelrobustlock lowlevelpilock \
pt-vfork \
ptw-write ptw-read ptw-close ptw-fcntl ptw-accept \
ptw-connect ptw-recv ptw-recvfrom ptw-recvmsg
ptw-send \
diff --git a/nptl/Versions b/nptl/Versions
index bb11277..2c7504e 100644
--- a/nptl/Versions
+++ b/nptl/Versions
@@ -257,6 +257,11 @@ libpthread {
pthread_setattr_default_np;
}
+ GLIBC_2.19 {
+ pthread_condattr_getprotocol_np;
+ pthread_condattr_setprotocol_np;
+ }
+
GLIBC_PRIVATE {
__pthread_initialize_minimal;
__pthread_clock_gettime; __pthread_clock_settime;
diff --git a/nptl/pthread_cond_broadcast.c b/nptl/pthread_cond_broadcast.c
index 7ba9efa..60209f2 100644
--- a/nptl/pthread_cond_broadcast.c
+++ b/nptl/pthread_cond_broadcast.c
@@ -27,6 +27,7 @@
#include <shlib-compat.h>
#include <kernel-features.h>
+#include "cond-lock.h"
int
__pthread_cond_broadcast (cond)
@@ -37,7 +38,7 @@ __pthread_cond_broadcast (cond)
int pshared = (cond->__data.__mutex == (void *) ~0l)
? LLL_SHARED : LLL_PRIVATE;
/* Make sure we are alone. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* Are there any waiters to be woken? */
if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
@@ -51,7 +52,7 @@ __pthread_cond_broadcast (cond)
++cond->__data.__broadcast_seq;
/* We are done. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
/* Wake everybody. */
pthread_mutex_t *mut = (pthread_mutex_t *) cond->__data.__mutex;
@@ -84,7 +85,7 @@ wake_all:
}
/* We are done. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return 0;
}
diff --git a/nptl/pthread_cond_destroy.c b/nptl/pthread_cond_destroy.c
index ebf1505..f1a3af7 100644
--- a/nptl/pthread_cond_destroy.c
+++ b/nptl/pthread_cond_destroy.c
@@ -21,6 +21,7 @@
#include "pthreadP.h"
#include <stap-probe.h>
+#include "cond-lock.h"
int
__pthread_cond_destroy (cond)
@@ -32,13 +33,13 @@ __pthread_cond_destroy (cond)
LIBC_PROBE (cond_destroy, 1, cond);
/* Make sure we are alone. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
{
/* If there are still some waiters which have not been
woken up, this is an application bug. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return EBUSY;
}
@@ -70,11 +71,11 @@ __pthread_cond_destroy (cond)
do
{
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
lll_futex_wait (&cond->__data.__nwaiters, nwaiters, pshared);
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
nwaiters = cond->__data.__nwaiters;
}
diff --git a/nptl/pthread_cond_init.c b/nptl/pthread_cond_init.c
index 7789728..c6ba0df 100644
--- a/nptl/pthread_cond_init.c
+++ b/nptl/pthread_cond_init.c
@@ -31,9 +31,27 @@ __pthread_cond_init (cond, cond_attr)
cond->__data.__lock = LLL_LOCK_INITIALIZER;
cond->__data.__futex = 0;
cond->__data.__nwaiters = (icond_attr != NULL
- ? ((icond_attr->value >> 1)
- & ((1 << COND_NWAITERS_SHIFT) - 1))
+ ? ((icond_attr->value &
CONDATTR_CLOCKID_MASK)
+ >> CONDATTR_CLOCKID_SHIFT)
: CLOCK_REALTIME);
+ if (icond_attr != NULL)
+ {
+ switch ((icond_attr->value & CONDATTR_PROTOCOL_MASK)
+ >> CONDATTR_PROTOCOL_SHIFT)
+ {
+ case PTHREAD_PRIO_INHERIT:
+ cond->__data.__nwaiters |= COND_PRIO_INHERIT;
+ break;
+
+ case PTHREAD_PRIO_PROTECT:
+ cond->__data.__nwaiters |= COND_PRIO_PROTECT;
+ break;
+
+ default:
+ break;
+ }
+ }
+
cond->__data.__total_seq = 0;
cond->__data.__wakeup_seq = 0;
cond->__data.__woken_seq = 0;
diff --git a/nptl/pthread_cond_signal.c b/nptl/pthread_cond_signal.c
index ffc35dc..2067cd1 100644
--- a/nptl/pthread_cond_signal.c
+++ b/nptl/pthread_cond_signal.c
@@ -27,6 +27,7 @@
#include <kernel-features.h>
#include <stap-probe.h>
+#include "cond-lock.h"
int
__pthread_cond_signal (cond)
@@ -38,7 +39,7 @@ __pthread_cond_signal (cond)
LIBC_PROBE (cond_signal, 1, cond);
/* Make sure we are alone. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* Are there any waiters to be woken? */
if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
@@ -58,7 +59,7 @@ __pthread_cond_signal (cond)
&mut->__data.__lock,
cond->__data.__futex, pshared) ==
0)
{
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return 0;
}
else
@@ -75,7 +76,7 @@ __pthread_cond_signal (cond)
}
/* We are done. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return 0;
}
diff --git a/nptl/pthread_cond_timedwait.c b/nptl/pthread_cond_timedwait.c
index 0a2d092..1e59b49 100644
--- a/nptl/pthread_cond_timedwait.c
+++ b/nptl/pthread_cond_timedwait.c
@@ -26,6 +26,8 @@
#include <shlib-compat.h>
+#include "cond-lock.h"
+
#ifndef HAVE_CLOCK_GETTIME_VSYSCALL
# undef INTERNAL_VSYSCALL
# define INTERNAL_VSYSCALL INTERNAL_SYSCALL
@@ -70,13 +72,13 @@ __pthread_cond_timedwait (cond, mutex, abstime)
#endif
/* Make sure we are alone. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* Now we can release the mutex. */
int err = __pthread_mutex_unlock_usercnt (mutex, 0);
if (err)
{
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return err;
}
@@ -121,8 +123,7 @@ __pthread_cond_timedwait (cond, mutex, abstime)
# ifdef __NR_clock_gettime
INTERNAL_SYSCALL_DECL (err);
(void) INTERNAL_VSYSCALL (clock_gettime, err, 2,
- (cond->__data.__nwaiters
- & ((1 << COND_NWAITERS_SHIFT) - 1)),
+ cond->__data.__nwaiters &
COND_CLOCKID_MASK,
&rt);
/* Convert the absolute timeout value to a relative timeout. */
rt.tv_sec = abstime->tv_sec - rt.tv_sec;
@@ -155,7 +156,7 @@ __pthread_cond_timedwait (cond, mutex, abstime)
unsigned int futex_val = cond->__data.__futex;
/* Prepare to wait. Release the condvar futex. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
/* Enable asynchronous cancellation. Required by the standard. */
cbuffer.oldtype = __pthread_enable_asynccancel ();
@@ -205,7 +206,7 @@ __pthread_cond_timedwait (cond, mutex, abstime)
__pthread_disable_asynccancel (cbuffer.oldtype);
/* We are going to look at shared data again, so get the lock. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* If a broadcast happened, we are done. */
if (cbuffer.bc_seq != cond->__data.__broadcast_seq)
@@ -245,7 +246,7 @@ __pthread_cond_timedwait (cond, mutex, abstime)
lll_futex_wake (&cond->__data.__nwaiters, 1, pshared);
/* We are done with the condvar. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
/* The cancellation handling is back to normal, remove the handler. */
__pthread_cleanup_pop (&buffer, 0);
diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
index 01d42d7..0231476 100644
--- a/nptl/pthread_cond_wait.c
+++ b/nptl/pthread_cond_wait.c
@@ -26,6 +26,8 @@
#include <shlib-compat.h>
#include <stap-probe.h>
+#include "cond-lock.h"
+
struct _condvar_cleanup_buffer
{
int oldtype;
@@ -46,7 +48,7 @@ __condvar_cleanup (void *arg)
? LLL_SHARED : LLL_PRIVATE;
/* We are going to modify shared data. */
- lll_lock (cbuffer->cond->__data.__lock, pshared);
+ cond_lock (cbuffer->cond, pshared);
if (cbuffer->bc_seq == cbuffer->cond->__data.__broadcast_seq)
{
@@ -77,7 +79,7 @@ __condvar_cleanup (void *arg)
}
/* We are done. */
- lll_unlock (cbuffer->cond->__data.__lock, pshared);
+ cond_unlock (cbuffer->cond, pshared);
/* Wake everybody to make sure no condvar signal gets lost. */
if (! destroying)
@@ -115,13 +117,13 @@ __pthread_cond_wait (cond, mutex)
LIBC_PROBE (cond_wait, 2, cond, mutex);
/* Make sure we are alone. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* Now we can release the mutex. */
err = __pthread_mutex_unlock_usercnt (mutex, 0);
if (__builtin_expect (err, 0))
{
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
return err;
}
@@ -156,7 +158,7 @@ __pthread_cond_wait (cond, mutex)
{
unsigned int futex_val = cond->__data.__futex;
/* Prepare to wait. Release the condvar futex. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
/* Enable asynchronous cancellation. Required by the standard. */
cbuffer.oldtype = __pthread_enable_asynccancel ();
@@ -190,7 +192,7 @@ __pthread_cond_wait (cond, mutex)
__pthread_disable_asynccancel (cbuffer.oldtype);
/* We are going to look at shared data again, so get the lock. */
- lll_lock (cond->__data.__lock, pshared);
+ cond_lock (cond, pshared);
/* If a broadcast happened, we are done. */
if (cbuffer.bc_seq != cond->__data.__broadcast_seq)
@@ -216,7 +218,7 @@ __pthread_cond_wait (cond, mutex)
lll_futex_wake (&cond->__data.__nwaiters, 1, pshared);
/* We are done with the condvar. */
- lll_unlock (cond->__data.__lock, pshared);
+ cond_unlock (cond, pshared);
/* The cancellation handling is back to normal, remove the handler. */
__pthread_cleanup_pop (&buffer, 0);
diff --git a/nptl/pthread_condattr_getclock.c
b/nptl/pthread_condattr_getclock.c
index f236986..0f571ff 100644
--- a/nptl/pthread_condattr_getclock.c
+++ b/nptl/pthread_condattr_getclock.c
@@ -24,7 +24,8 @@ pthread_condattr_getclock (attr, clock_id)
const pthread_condattr_t *attr;
clockid_t *clock_id;
{
- *clock_id = (((((const struct pthread_condattr *) attr)->value) >> 1)
- & ((1 << COND_NWAITERS_SHIFT) - 1));
+ *clock_id = ((((const struct pthread_condattr *) attr)->value
+ & CONDATTR_CLOCKID_MASK) >> CONDATTR_CLOCKID_SHIFT);
+
return 0;
}
diff --git a/nptl/pthread_condattr_getprotocol_np.c
b/nptl/pthread_condattr_getprotocol_np.c
new file mode 100644
index 0000000..2507f20
--- /dev/null
+++ b/nptl/pthread_condattr_getprotocol_np.c
@@ -0,0 +1,30 @@
+/* Copyright (C) 2013 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>
+
+
+int
+pthread_condattr_getprotocol_np (attr, protocol)
+ const pthread_condattr_t *attr;
+ int *protocol;
+{
+ *protocol = ((((const struct pthread_condattr *) attr)->value
+ & CONDATTR_PROTOCOL_MASK) >> CONDATTR_PROTOCOL_SHIFT);
+
+ return 0;
+}
diff --git a/nptl/pthread_condattr_getpshared.c
b/nptl/pthread_condattr_getpshared.c
index 58992ab..eaff068 100644
--- a/nptl/pthread_condattr_getpshared.c
+++ b/nptl/pthread_condattr_getpshared.c
@@ -24,7 +24,8 @@ pthread_condattr_getpshared (attr, pshared)
const pthread_condattr_t *attr;
int *pshared;
{
- *pshared = ((const struct pthread_condattr *) attr)->value & 1;
+ *pshared = (((const struct pthread_condattr *) attr)->value
+ & CONDATTR_PSHARED_MASK);
return 0;
}
diff --git a/nptl/pthread_condattr_setclock.c
b/nptl/pthread_condattr_setclock.c
index f806771..44dce50 100644
--- a/nptl/pthread_condattr_setclock.c
+++ b/nptl/pthread_condattr_setclock.c
@@ -37,12 +37,12 @@ pthread_condattr_setclock (attr, clock_id)
return EINVAL;
/* Make sure the value fits in the bits we reserved. */
- assert (clock_id < (1 << COND_NWAITERS_SHIFT));
+ assert (clock_id < (1 << COND_PROTOCOL_SHIFT));
int *valuep = &((struct pthread_condattr *) attr)->value;
- *valuep = ((*valuep & ~(((1 << COND_NWAITERS_SHIFT) - 1) << 1))
- | (clock_id << 1));
+ *valuep = ((*valuep & ~CONDATTR_CLOCKID_MASK)
+ | (clock_id << CONDATTR_CLOCKID_SHIFT));
return 0;
}
diff --git a/nptl/pthread_condattr_setprotocol_np.c
b/nptl/pthread_condattr_setprotocol_np.c
new file mode 100644
index 0000000..f773d4a
--- /dev/null
+++ b/nptl/pthread_condattr_setprotocol_np.c
@@ -0,0 +1,38 @@
+/* Copyright (C) 2013 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 <errno.h>
+#include <pthreadP.h>
+
+
+int
+pthread_condattr_setprotocol_np (attr, protocol)
+ pthread_condattr_t *attr;
+ int protocol;
+{
+ if (protocol != PTHREAD_PRIO_NONE
+ && protocol != PTHREAD_PRIO_INHERIT
+ && __builtin_expect (protocol != PTHREAD_PRIO_PROTECT, 0))
+ return EINVAL;
+
+ int *valuep = &((struct pthread_condattr *) attr)->value;
+
+ *valuep = ((*valuep & ~CONDATTR_PROTOCOL_MASK)
+ | (protocol << CONDATTR_PROTOCOL_SHIFT));
+
+ return 0;
+}
diff --git a/nptl/pthread_condattr_setpshared.c
b/nptl/pthread_condattr_setpshared.c
index 3067227..b7cf472 100644
--- a/nptl/pthread_condattr_setpshared.c
+++ b/nptl/pthread_condattr_setpshared.c
@@ -30,7 +30,8 @@ pthread_condattr_setpshared (attr, pshared)
int *valuep = &((struct pthread_condattr *) attr)->value;
- *valuep = (*valuep & ~1) | (pshared != PTHREAD_PROCESS_PRIVATE);
+ *valuep = ((*valuep & ~CONDATTR_PSHARED_MASK)
+ | (pshared != PTHREAD_PROCESS_PRIVATE));
return 0;
}
diff --git a/nptl/sysdeps/pthread/cond-lock.h
b/nptl/sysdeps/pthread/cond-lock.h
new file mode 100644
index 0000000..86a0e15
--- /dev/null
+++ b/nptl/sysdeps/pthread/cond-lock.h
@@ -0,0 +1,62 @@
+/* Copyright (C) 2013 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/>. */
+
+#ifndef _COND_LOCK_H
+#define _COND_LOCK_H 1
+
+#ifdef __ASSUME_FUTEX_LOCK_PI
+extern void __lll_pi_lock (int *futex, int private) attribute_hidden;
+extern void __lll_pi_unlock (int *futex, int private) attribute_hidden;
+
+#define lll_pi_lock(futex, private) __lll_pi_lock (&(futex), private)
+#define lll_pi_unlock(futex, private) __lll_pi_unlock (&(futex), private)
+#else
+#define lll_pi_lock(futex, private) lll_lock (futex, private)
+#define lll_pi_unlock(futex, private) lll_unlock (futex, private)
+#endif
+
+static inline void cond_lock(pthread_cond_t *cond,
+ int pshared);
+
+static inline void cond_unlock(pthread_cond_t *cond,
+ int pshared);
+
+static inline void cond_lock(cond, pshared)
+ pthread_cond_t *cond;
+ int pshared;
+{
+ if (pshared == LLL_PRIVATE
+ && ((cond->__data.__nwaiters & COND_PROTOCOL_MASK)
+ == COND_PRIO_INHERIT))
+ lll_pi_lock (cond->__data.__lock, pshared);
+ else
+ lll_lock (cond->__data.__lock, pshared);
+}
+
+static inline void cond_unlock(cond, pshared)
+ pthread_cond_t *cond;
+ int pshared;
+{
+ if (pshared == LLL_PRIVATE
+ && ((cond->__data.__nwaiters & COND_PROTOCOL_MASK)
+ == COND_PRIO_INHERIT))
+ lll_pi_unlock (cond->__data.__lock, pshared);
+ else
+ lll_unlock (cond->__data.__lock, pshared);
+}
+
+#endif
diff --git a/nptl/sysdeps/pthread/pthread.h
b/nptl/sysdeps/pthread/pthread.h
index b58f60e..a0b8d69 100644
--- a/nptl/sysdeps/pthread/pthread.h
+++ b/nptl/sysdeps/pthread/pthread.h
@@ -832,6 +832,18 @@ extern int pthread_mutexattr_setpshared
(pthread_mutexattr_t *__attr,
int __pshared)
__THROW __nonnull ((1));
+/* Get the protocol flag of the condition variable attribute ATTR. */
+extern int pthread_condattr_getprotocol_np (__const pthread_condattr_t *
+ __restrict __attr,
+ int *__restrict __protocol)
+ __THROW __nonnull ((1, 2));
+
+/* Set the cond protocol attribute in ATTR to protocol (one of
+ PTHREAD_PRIO_NONE, PTHREAD_PRIO_INHERIT or PTHREAD_PRIO_PROTECT). */
+extern int pthread_condattr_setprotocol_np (pthread_condattr_t *__attr,
+ int __protocol)
+ __THROW __nonnull ((1));
+
#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
/* Return in *KIND the mutex kind attribute in *ATTR. */
extern int pthread_mutexattr_gettype (const pthread_mutexattr_t
*__restrict
diff --git a/nptl/sysdeps/unix/sysv/linux/internaltypes.h
b/nptl/sysdeps/unix/sysv/linux/internaltypes.h
index a7ee3fe..89f9036 100644
--- a/nptl/sysdeps/unix/sysv/linux/internaltypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/internaltypes.h
@@ -69,18 +69,35 @@ struct pthread_condattr
Bit 0 : flag whether conditional variable will be sharable between
processes.
- Bit 1-7: clock ID. */
+ Bit 1 : clock ID.
+ Bit 2-3: protocol. One of PTHREAD_PRIO_NONE, PTHREAD_PRIO_INHERIT
+ or PTHREAD_PRIO_PROTECT. */
int value;
};
+#define CONDATTR_PSHARED_MASK 0x00000001
+#define CONDATTR_CLOCKID_MASK 0x00000002
+#define CONDATTR_CLOCKID_SHIFT 1
+#define CONDATTR_PROTOCOL_MASK 0x0000000C
+#define CONDATTR_PROTOCOL_SHIFT 2
+
+
+enum {
+ COND_PRIO_INHERIT = 2,
+ COND_PRIO_PROTECT
+};
+
+
/* The __NWAITERS field is used as a counter and to house the number
- of bits for other purposes. COND_CLOCK_BITS is the number
- of bits needed to represent the ID of the clock. COND_NWAITERS_SHIFT
+ of bits for other purposes. COND_CLOCKID_MASK defines the bits used
+ to represent the ID of the clock. COND_PROTOCOL_MASK defines the
+ bits used to represent cond protocol attributes. COND_NWAITERS_SHIFT
is the number of bits reserved for other purposes like the clock. */
-#define COND_CLOCK_BITS 1
-#define COND_NWAITERS_SHIFT 1
-
+#define COND_CLOCKID_MASK 0x00000001
+#define COND_PROTOCOL_SHIFT 1
+#define COND_PROTOCOL_MASK 0x00000006
+#define COND_NWAITERS_SHIFT 3
/* Read-write lock variable attribute data structure. */
struct pthread_rwlockattr
diff --git a/nptl/sysdeps/unix/sysv/linux/lowlevelpilock.c
b/nptl/sysdeps/unix/sysv/linux/lowlevelpilock.c
new file mode 100644
index 0000000..0845fcf
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/lowlevelpilock.c
@@ -0,0 +1,61 @@
+/* Copyright (C) 2013 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 <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <sys/time.h>
+#include <pthreadP.h>
+
+
+void
+ __attribute__ ((visibility ("hidden")))
+__lll_pi_lock(int *futexp, int private)
+{
+ pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
+ int newval = id;
+ int ret;
+
+ newval |= FUTEX_WAITERS;
+ ret = atomic_compare_and_exchange_val_acq (futexp, newval, 0);
+
+ if (ret != 0)
+ {
+ /* The mutex is locked. The kernel will now take care of
+ everything. */
+ INTERNAL_SYSCALL_DECL (__err);
+ INTERNAL_SYSCALL (futex, __err, 4, futexp,
+ __lll_private_flag (FUTEX_LOCK_PI, private), 1,
0);
+ }
+}
+
+
+void
+__attribute__ ((visibility ("hidden")))
+__lll_pi_unlock(int *futexp, int private)
+{
+
+ if ((*futexp & FUTEX_WAITERS) != 0
+ || atomic_compare_and_exchange_bool_acq (futexp, 0,
+ THREAD_GETMEM (THREAD_SELF,
+ tid)))
+ {
+ INTERNAL_SYSCALL_DECL (__err);
+ INTERNAL_SYSCALL (futex, __err, 2, futexp,
+ __lll_private_flag (FUTEX_UNLOCK_PI, private));
+ }
+}
diff --git a/ports/sysdeps/unix/sysv/linux/arm/nptl/libpthread.abilist
b/ports/sysdeps/unix/sysv/linux/arm/nptl/libpthread.abilist
index ac46302..c7f5472 100644
--- a/ports/sysdeps/unix/sysv/linux/arm/nptl/libpthread.abilist
+++ b/ports/sysdeps/unix/sysv/linux/arm/nptl/libpthread.abilist
@@ -12,6 +12,10 @@ GLIBC_2.18
GLIBC_2.18 A
pthread_getattr_default_np F
pthread_setattr_default_np F
+GLIBC_2.19
+ GLIBC_2.19 A
+ pthread_condattr_getprotocol_np F
+ pthread_condattr_setprotocol_np F
GLIBC_2.4
GLIBC_2.4 A
_IO_flockfile F
diff --git a/sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist
b/sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist
index 865364e..4bcc681 100644
--- a/sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist
+++ b/sysdeps/unix/sysv/linux/i386/nptl/libpthread.abilist
@@ -178,6 +178,10 @@ GLIBC_2.18
GLIBC_2.18 A
pthread_getattr_default_np F
pthread_setattr_default_np F
+GLIBC_2.19
+ GLIBC_2.19 A
+ pthread_condattr_getprotocol_np F
+ pthread_condattr_setprotocol_np F
GLIBC_2.2
GLIBC_2.2 A
__open64 F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/nptl/libpthread.abilist
b/sysdeps/unix/sysv/linux/x86_64/64/nptl/libpthread.abilist
index 1b5192b..6ca2588 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/nptl/libpthread.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/nptl/libpthread.abilist
@@ -12,6 +12,10 @@ GLIBC_2.18
GLIBC_2.18 A
pthread_getattr_default_np F
pthread_setattr_default_np F
+GLIBC_2.19
+ GLIBC_2.19 A
+ pthread_condattr_getprotocol_np F
+ pthread_condattr_setprotocol_np F
GLIBC_2.2.5
GLIBC_2.2.5 A
_IO_flockfile F
--
1.8.1.2