Fix stack zio_execute()

Implement zio_execute() as a wrapper around the static function
__zio_execute() so that we can force  __zio_execute() to be inlined.
This reduces stack overhead which is important because __zio_execute()
is called recursively in several zio code paths.  zio_execute() itself
cannot be inlined because it is externally visible.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This commit is contained in:
Ned Bass 2010-08-26 11:38:38 -07:00 committed by Brian Behlendorf
parent c776b317e4
commit da6b4005c9

View File

@ -93,6 +93,8 @@ int zio_buf_debug_limit = 16384;
int zio_buf_debug_limit = 0;
#endif
static inline void __zio_execute(zio_t *zio);
void
zio_init(void)
{
@ -451,7 +453,7 @@ zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait)
if (--*countp == 0 && pio->io_stall == countp) {
pio->io_stall = NULL;
mutex_exit(&pio->io_lock);
zio_execute(pio);
__zio_execute(pio);
} else {
mutex_exit(&pio->io_lock);
}
@ -1122,8 +1124,23 @@ zio_interrupt(zio_t *zio)
*/
static zio_pipe_stage_t *zio_pipeline[];
/*
* zio_execute() is a wrapper around the static function
* __zio_execute() so that we can force __zio_execute() to be
* inlined. This reduces stack overhead which is important
* because __zio_execute() is called recursively in several zio
* code paths. zio_execute() itself cannot be inlined because
* it is externally visible.
*/
void
zio_execute(zio_t *zio)
{
__zio_execute(zio);
}
__attribute__((always_inline))
static inline void
__zio_execute(zio_t *zio)
{
zio->io_executor = curthread;
@ -1169,6 +1186,7 @@ zio_execute(zio_t *zio)
}
}
/*
* ==========================================================================
* Initiate I/O, either sync or async
@ -1184,7 +1202,7 @@ zio_wait(zio_t *zio)
zio->io_waiter = curthread;
zio_execute(zio);
__zio_execute(zio);
mutex_enter(&zio->io_lock);
while (zio->io_executor != NULL)
@ -1214,7 +1232,7 @@ zio_nowait(zio_t *zio)
zio_add_child(spa->spa_async_zio_root, zio);
}
zio_execute(zio);
__zio_execute(zio);
}
/*
@ -1269,7 +1287,7 @@ zio_reexecute(zio_t *pio)
* responsibility of the caller to wait on him.
*/
if (!(pio->io_flags & ZIO_FLAG_GODFATHER))
zio_execute(pio);
__zio_execute(pio);
}
void