From 28bc3b8c71cda033a4c013131c635d1148889824 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Thu, 14 Aug 2014 18:33:30 +0200 Subject: drbd: Fix locking across all resources Instead of using a rwlock for synchronizing state changes across resources, take the request locks of all resources for global state changes. Use resources_mutex to serialize global state changes. This means that taking the request lock of a resource is now enough to prevent changes of that resource. (Previously, a read lock on the global state lock was needed as well.) Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_int.h | 18 ++++-------------- 1 file changed, 4 insertions(+), 14 deletions(-) (limited to 'drivers/block/drbd/drbd_int.h') diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 47d4b02103b8..2c9ee223d548 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -292,6 +292,9 @@ struct drbd_device_work { extern int drbd_wait_misc(struct drbd_device *, struct drbd_interval *); +extern void lock_all_resources(void); +extern void unlock_all_resources(void); + struct drbd_request { struct drbd_work w; struct drbd_device *device; @@ -1418,7 +1421,7 @@ extern struct bio_set *drbd_md_io_bio_set; /* to allocate from that set */ extern struct bio *bio_alloc_drbd(gfp_t gfp_mask); -extern rwlock_t global_state_lock; +extern struct mutex resources_mutex; extern int conn_lowest_minor(struct drbd_connection *connection); extern enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor); @@ -1688,19 +1691,6 @@ static inline int drbd_peer_req_has_active_page(struct drbd_peer_request *peer_r return 0; } -static inline enum drbd_state_rv -_drbd_set_state(struct drbd_device *device, union drbd_state ns, - enum chg_state_flags flags, struct completion *done) -{ - enum drbd_state_rv rv; - - read_lock(&global_state_lock); - rv = __drbd_set_state(device, ns, flags, done); - read_unlock(&global_state_lock); - - return rv; -} - static inline union drbd_state drbd_read_state(struct drbd_device *device) { struct drbd_resource *resource = device->resource; -- cgit v1.2.3