MD code uses perpcu-refcount internal to check if this percpu-refcount variable is initialized, this way is a hack.
Add percpu_ref_is_initialized for MD so that the hack can be avoided. Acked-by: Song Liu <[email protected]> Suggested-by: Jens Axboe <[email protected]> Tested-by: Veronika Kabatova <[email protected]> Cc: Song Liu <[email protected]> Cc: [email protected] Cc: Sagi Grimberg <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Bart Van Assche <[email protected]> Signed-off-by: Ming Lei <[email protected]> --- drivers/md/md.c | 2 +- include/linux/percpu-refcount.h | 1 + lib/percpu-refcount.c | 6 ++++++ 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 9562ef598ae1..3c711f2968a9 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5632,7 +5632,7 @@ static void no_op(struct percpu_ref *r) {} int mddev_init_writes_pending(struct mddev *mddev) { - if (mddev->writes_pending.percpu_count_ptr) + if (percpu_ref_is_initialized(&mddev->writes_pending)) return 0; if (percpu_ref_init(&mddev->writes_pending, no_op, PERCPU_REF_ALLOW_REINIT, GFP_KERNEL) < 0) diff --git a/include/linux/percpu-refcount.h b/include/linux/percpu-refcount.h index 87d8a38bdea1..2dfdf870f2d0 100644 --- a/include/linux/percpu-refcount.h +++ b/include/linux/percpu-refcount.h @@ -109,6 +109,7 @@ struct percpu_ref { int __must_check percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release, unsigned int flags, gfp_t gfp); +bool percpu_ref_is_initialized(struct percpu_ref *ref); void percpu_ref_exit(struct percpu_ref *ref); void percpu_ref_switch_to_atomic(struct percpu_ref *ref, percpu_ref_func_t *confirm_switch); diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 0ba686b8fe57..db2ec682e0f7 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -93,6 +93,12 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release, } EXPORT_SYMBOL_GPL(percpu_ref_init); +bool percpu_ref_is_initialized(struct percpu_ref *ref) +{ + return percpu_count_ptr(ref) != NULL; +} +EXPORT_SYMBOL_GPL(percpu_ref_is_initialized); + /** * percpu_ref_exit - undo percpu_ref_init() * @ref: percpu_ref to exit -- 2.25.2
