| Message ID | 20220426085114.199647-8-eesposit@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Removal of AioContext lock, bs->parents and ->children: new rwlock | expand |
On Tue, Apr 26, 2022 at 04:51:13AM -0400, Emanuele Giuseppe Esposito wrote: > Similar to the implementation in lockable.h, implement macros to > automatically take and release the rdlock. > Create the empty GraphLockable struct only to use it as a type for > G_DEFINE_AUTOPTR_CLEANUP_FUNC. > > Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> > --- > include/block/graph-lock.h | 30 ++++++++++++++++++++++++++++++ > 1 file changed, 30 insertions(+) > > diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h > index 2211d41286..8d8a6513f1 100644 > --- a/include/block/graph-lock.h > +++ b/include/block/graph-lock.h > @@ -67,5 +67,35 @@ void assert_bdrv_graph_readable(void); > */ > void assert_bdrv_graph_writable(void); > > +typedef struct GraphLockable { } GraphLockable; > + > +#define GML_OBJ_() (&(GraphLockable) { }) The comment for QML_OBJ_() is helpful. This takes advantage of the lifetime of compound literals and it's different in C and C++. I suggest keeping it for the benefit for people trying to understand how this works.
diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index 2211d41286..8d8a6513f1 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -67,5 +67,35 @@ void assert_bdrv_graph_readable(void); */ void assert_bdrv_graph_writable(void); +typedef struct GraphLockable { } GraphLockable; + +#define GML_OBJ_() (&(GraphLockable) { }) + +static inline GraphLockable *graph_lockable_auto_lock(GraphLockable *x) +{ + bdrv_graph_co_rdlock(); + return x; +} + +static inline void graph_lockable_auto_unlock(GraphLockable *x) +{ + bdrv_graph_co_rdunlock(); +} + +G_DEFINE_AUTOPTR_CLEANUP_FUNC(GraphLockable, graph_lockable_auto_unlock) + +#define WITH_GRAPH_RDLOCK_GUARD_(var) \ + for (g_autoptr(GraphLockable) var = graph_lockable_auto_lock(GML_OBJ_()); \ + var; \ + graph_lockable_auto_unlock(var), var = NULL) + +#define WITH_GRAPH_RDLOCK_GUARD() \ + WITH_GRAPH_RDLOCK_GUARD_(glue(graph_lockable_auto, __COUNTER__)) + +#define GRAPH_RDLOCK_GUARD(x) \ + g_autoptr(GraphLockable) \ + glue(graph_lockable_auto, __COUNTER__) G_GNUC_UNUSED = \ + graph_lockable_auto_lock(GML_OBJ_()) + #endif /* BLOCK_LOCK_H */
Similar to the implementation in lockable.h, implement macros to automatically take and release the rdlock. Create the empty GraphLockable struct only to use it as a type for G_DEFINE_AUTOPTR_CLEANUP_FUNC. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> --- include/block/graph-lock.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+)