| Message ID | 20221122205739.603510-2-richard.henderson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | main-loop: Introduce QEMU_IOTHREAD_LOCK_GUARD | expand |
On 22/11/22 21:57, Richard Henderson wrote: > Create a couple of wrappers for locking/unlocking the iothread lock. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > include/qemu/main-loop.h | 39 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 39 insertions(+) > +#define QEMU_IOTHREAD_LOCK_GUARD() \ > + g_auto(IOThreadLockAuto) _iothread_lock_auto \ > + = qemu_iothread_auto_lock(__FILE__, __LINE__) \ > + > +#define WITH_QEMU_IOTHREAD_LOCK() \ > + for (QEMU_IOTHREAD_LOCK_GUARD(); \ > + _iothread_lock_auto.iterate; \ > + _iothread_lock_auto.iterate = false) Nice, thanks! Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
On 11/22/22 12:57, Richard Henderson wrote: > +#define QEMU_IOTHREAD_LOCK_GUARD() \ > + g_auto(IOThreadLockAuto) _iothread_lock_auto \ > + = qemu_iothread_auto_lock(__FILE__, __LINE__) \ Need an extra G_GNUC_UNUSED for (some versions of?) clang. Which is really a bug, because it's always used via the cleanup. r~
diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h index 3c9a9a982d..73c60a9af4 100644 --- a/include/qemu/main-loop.h +++ b/include/qemu/main-loop.h @@ -343,6 +343,45 @@ void qemu_mutex_lock_iothread_impl(const char *file, int line); */ void qemu_mutex_unlock_iothread(void); +/** + * QEMU_IOTHREAD_LOCK_GUARD + * WITH_QEMU_IOTHREAD_LOCK + * + * Wrap a block of code in a conditional qemu_mutex_{lock,unlock}_iothread. + */ +typedef struct IOThreadLockAuto { + bool locked; + bool iterate; +} IOThreadLockAuto; + +static inline IOThreadLockAuto qemu_iothread_auto_lock(const char *file, + int line) +{ + bool need = !qemu_mutex_iothread_locked(); + if (need) { + qemu_mutex_lock_iothread_impl(file, line); + } + return (IOThreadLockAuto){ .locked = need, .iterate = true }; +} + +static inline void qemu_iothread_auto_unlock(IOThreadLockAuto *l) +{ + if (l->locked) { + qemu_mutex_unlock_iothread(); + } +} + +G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(IOThreadLockAuto, qemu_iothread_auto_unlock) + +#define QEMU_IOTHREAD_LOCK_GUARD() \ + g_auto(IOThreadLockAuto) _iothread_lock_auto \ + = qemu_iothread_auto_lock(__FILE__, __LINE__) \ + +#define WITH_QEMU_IOTHREAD_LOCK() \ + for (QEMU_IOTHREAD_LOCK_GUARD(); \ + _iothread_lock_auto.iterate; \ + _iothread_lock_auto.iterate = false) + /* * qemu_cond_wait_iothread: Wait on condition for the main loop mutex *
Create a couple of wrappers for locking/unlocking the iothread lock. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- include/qemu/main-loop.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)