Il 09/08/2012 09:28, liu ping fan ha scritto: > On Wed, Aug 8, 2012 at 5:41 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: >> Il 08/08/2012 08:25, Liu Ping Fan ha scritto: >>> From: Liu Ping Fan <pingfank@xxxxxxxxxxxxxxxxxx> >>> >>> Signed-off-by: Liu Ping Fan <pingfank@xxxxxxxxxxxxxxxxxx> >>> --- >>> cpus.c | 12 ++++++++++++ >>> main-loop.h | 3 +++ >>> 2 files changed, 15 insertions(+), 0 deletions(-) >>> >>> diff --git a/cpus.c b/cpus.c >>> index b182b3d..a734b36 100644 >>> --- a/cpus.c >>> +++ b/cpus.c >>> @@ -611,6 +611,7 @@ static void qemu_tcg_init_cpu_signals(void) >>> } >>> #endif /* _WIN32 */ >>> >>> +QemuMutex qemu_device_tree_mutex; >>> QemuMutex qemu_global_mutex; >>> static QemuCond qemu_io_proceeded_cond; >>> static bool iothread_requesting_mutex; >>> @@ -634,6 +635,7 @@ void qemu_init_cpu_loop(void) >>> qemu_cond_init(&qemu_work_cond); >>> qemu_cond_init(&qemu_io_proceeded_cond); >>> qemu_mutex_init(&qemu_global_mutex); >>> + qemu_mutex_init(&qemu_device_tree_mutex); >>> >>> qemu_thread_get_self(&io_thread); >>> } >>> @@ -911,6 +913,16 @@ void qemu_mutex_unlock_iothread(void) >>> qemu_mutex_unlock(&qemu_global_mutex); >>> } >>> >>> +void qemu_lock_devtree(void) >>> +{ >>> + qemu_mutex_lock(&qemu_device_tree_mutex); >>> +} >>> + >>> +void qemu_unlock_devtree(void) >>> +{ >>> + qemu_mutex_unlock(&qemu_device_tree_mutex); >>> +} >> >> We don't need the wrappers. They are there for the big lock just >> because TCG needs extra work for iothread_requesting_mutex. >> > Sorry, could you give more detail about TCG, what is extra work. void qemu_mutex_lock_iothread(void) { if (!tcg_enabled()) { qemu_mutex_lock(&qemu_global_mutex); } else { iothread_requesting_mutex = true; if (qemu_mutex_trylock(&qemu_global_mutex)) { qemu_cpu_kick_thread(first_cpu); qemu_mutex_lock(&qemu_global_mutex); } iothread_requesting_mutex = false; qemu_cond_broadcast(&qemu_io_proceeded_cond); } } You do not need any of the code in the "else" branch for the device tree mutex, so you do not need wrappers. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html