From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1dpCpO-0002yL-JA for mharc-qemu-trivial@gnu.org; Tue, 05 Sep 2017 08:19:40 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45120) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dpCpI-0002vs-8s for qemu-trivial@nongnu.org; Tue, 05 Sep 2017 08:19:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dpCpD-0001Wm-Aw for qemu-trivial@nongnu.org; Tue, 05 Sep 2017 08:19:32 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:37156) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dpCp3-0001Ry-9r; Tue, 05 Sep 2017 08:19:17 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.89) (envelope-from ) id 1dpCp0-0006zf-CH; Tue, 05 Sep 2017 13:19:14 +0100 From: Peter Maydell To: qemu-devel@nongnu.org, qemu-trivial@nongnu.org Cc: patches@linaro.org Date: Tue, 5 Sep 2017 13:19:32 +0100 Message-Id: <1504613972-15847-1-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 2.7.4 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2001:8b0:1d0::2 Subject: [Qemu-trivial] [PATCH] util/qemu-thread-posix.c: Replace OS ifdefs with CONFIG_HAVE_SEM_TIMEDWAIT X-BeenThere: qemu-trivial@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 Sep 2017 12:19:37 -0000 In qemu-thread-posix.c we have two implementations of the various qemu_sem_* functions, one of which uses native POSIX sem_* and the other of which emulates them with pthread conditions. This is necessary because not all our host OSes support sem_timedwait(). Instead of a hard-coded list of OSes which don't implement sem_timedwait(), which gets out of date, make configure test for the presence of the function and set a new CONFIG_HAVE_SEM_TIMEDWAIT appropriately. In particular, newer NetBSDs have sem_timedwait(), so this commit will switch them over to using it. OSX still does not have an implementation. Signed-off-by: Peter Maydell --- It would be nice to gradually reduce the number of places we do per-OS ifdeffery in favour of checking for the specific feature we care about in each case... Tested on Linux, NetBSD, OSX. configure | 15 +++++++++++++++ include/qemu/thread-posix.h | 2 +- util/qemu-thread-posix.c | 10 +++++----- 3 files changed, 21 insertions(+), 6 deletions(-) diff --git a/configure b/configure index fb7e34a..aa8d4d9 100755 --- a/configure +++ b/configure @@ -4448,6 +4448,18 @@ if compile_prog "" "" ; then fi ########################################## +# check if we have sem_timedwait + +sem_timedwait=no +cat > $TMPC << EOF +#include +int main(void) { return sem_timedwait(0, 0); } +EOF +if compile_prog "" "" ; then + sem_timedwait=yes +fi + +########################################## # check if trace backend exists $python "$source_path/scripts/tracetool.py" "--backends=$trace_backends" --check-backends > /dev/null 2> /dev/null @@ -5680,6 +5692,9 @@ fi if test "$inotify1" = "yes" ; then echo "CONFIG_INOTIFY1=y" >> $config_host_mak fi +if test "$sem_timedwait" = "yes" ; then + echo "CONFIG_SEM_TIMEDWAIT=y" >> $config_host_mak +fi if test "$byteswap_h" = "yes" ; then echo "CONFIG_BYTESWAP_H=y" >> $config_host_mak fi diff --git a/include/qemu/thread-posix.h b/include/qemu/thread-posix.h index e5e3a0f..f4296d3 100644 --- a/include/qemu/thread-posix.h +++ b/include/qemu/thread-posix.h @@ -21,7 +21,7 @@ struct QemuCond { }; struct QemuSemaphore { -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT pthread_mutex_t lock; pthread_cond_t cond; unsigned int count; diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c index 4e95d27..7306475 100644 --- a/util/qemu-thread-posix.c +++ b/util/qemu-thread-posix.c @@ -168,7 +168,7 @@ void qemu_sem_init(QemuSemaphore *sem, int init) { int rc; -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT rc = pthread_mutex_init(&sem->lock, NULL); if (rc != 0) { error_exit(rc, __func__); @@ -196,7 +196,7 @@ void qemu_sem_destroy(QemuSemaphore *sem) assert(sem->initialized); sem->initialized = false; -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT rc = pthread_cond_destroy(&sem->cond); if (rc < 0) { error_exit(rc, __func__); @@ -218,7 +218,7 @@ void qemu_sem_post(QemuSemaphore *sem) int rc; assert(sem->initialized); -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT pthread_mutex_lock(&sem->lock); if (sem->count == UINT_MAX) { rc = EINVAL; @@ -256,7 +256,7 @@ int qemu_sem_timedwait(QemuSemaphore *sem, int ms) struct timespec ts; assert(sem->initialized); -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT rc = 0; compute_abs_deadline(&ts, ms); pthread_mutex_lock(&sem->lock); @@ -304,7 +304,7 @@ void qemu_sem_wait(QemuSemaphore *sem) int rc; assert(sem->initialized); -#if defined(__APPLE__) || defined(__NetBSD__) +#ifndef CONFIG_SEM_TIMEDWAIT pthread_mutex_lock(&sem->lock); while (sem->count == 0) { rc = pthread_cond_wait(&sem->cond, &sem->lock); -- 2.7.4