From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:56170) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QTduu-0000Bs-8g for qemu-devel@nongnu.org; Mon, 06 Jun 2011 13:48:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QTdur-0003eP-MG for qemu-devel@nongnu.org; Mon, 06 Jun 2011 13:48:43 -0400 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:46616) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QTdur-0003e1-02 for qemu-devel@nongnu.org; Mon, 06 Jun 2011 13:48:41 -0400 Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [202.81.31.246]) by e23smtp03.au.ibm.com (8.14.4/8.13.1) with ESMTP id p56HhPdn012849 for ; Tue, 7 Jun 2011 03:43:25 +1000 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p56Hljli1237102 for ; Tue, 7 Jun 2011 03:47:46 +1000 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p56HmOjW002461 for ; Tue, 7 Jun 2011 03:48:25 +1000 From: "Aneesh Kumar K.V" Date: Mon, 6 Jun 2011 23:18:15 +0530 Message-Id: <1307382497-3737-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com> In-Reply-To: <1307382497-3737-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1307382497-3737-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 2/4] coroutine: Add CoRwlock support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: aliguori@us.ibm.com, "Aneesh Kumar K.V" Signed-off-by: Aneesh Kumar K.V --- qemu-coroutine-lock.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ qemu-coroutine.h | 12 ++++++++++++ 2 files changed, 56 insertions(+), 0 deletions(-) diff --git a/qemu-coroutine-lock.c b/qemu-coroutine-lock.c index 5071fb8..5ecaa94 100644 --- a/qemu-coroutine-lock.c +++ b/qemu-coroutine-lock.c @@ -115,3 +115,47 @@ void qemu_co_mutex_unlock(CoMutex *mutex) trace_qemu_co_mutex_unlock_return(mutex, self); } + +void qemu_co_rwlock_init(CoRwlock *lock) +{ + memset(lock, 0, sizeof(*lock)); + qemu_co_queue_init(&lock->queue); +} + +void qemu_co_rwlock_rdlock(CoRwlock *lock) +{ + while (lock->writer) { + qemu_co_queue_wait(&lock->queue); + } + lock->reader++; +} + +void qemu_co_rwlock_unlock(CoRwlock *lock) +{ + assert(qemu_in_coroutine()); + if (lock->writer) { + lock->writer--;; + assert(lock->writer == 0); + while (!qemu_co_queue_empty(&lock->queue)) { + /* + * Wakeup every body. This will include some + * writers too. + */ + qemu_co_queue_next(&lock->queue); + } + } else { + lock->reader--; + assert(lock->reader >= 0); + /* Wakeup only one waiting writer */ + qemu_co_queue_next(&lock->queue); + } +} + +void qemu_co_rwlock_wrlock(CoRwlock *lock) +{ + while (lock->writer || lock->reader) { + qemu_co_queue_wait(&lock->queue); + } + lock->writer++; + assert(lock->writer == 1); +} diff --git a/qemu-coroutine.h b/qemu-coroutine.h index 71cfa5a..a9735fb 100644 --- a/qemu-coroutine.h +++ b/qemu-coroutine.h @@ -17,6 +17,7 @@ #include #include "qemu-queue.h" +#include "qemu-thread.h" /** * Coroutines are a mechanism for stack switching and can be used for @@ -114,4 +115,15 @@ void qemu_co_mutex_init(CoMutex *mutex); void qemu_co_mutex_lock(CoMutex *mutex); void qemu_co_mutex_unlock(CoMutex *mutex); +typedef struct CoRwlock { + bool writer; + int reader; + CoQueue queue; +} CoRwlock; + +void qemu_co_rwlock_init(CoRwlock *lock); +void qemu_co_rwlock_rdlock(CoRwlock *lock); +void qemu_co_rwlock_wrlock(CoRwlock *lock); +void qemu_co_rwlock_unlock(CoRwlock *lock); + #endif /* QEMU_COROUTINE_H */ -- 1.7.4.1