Message ID | 20190715143705.117908-7-joel@joelfernandes.org (mailing list archive) |
---|---|
State | Not Applicable, archived |
Headers | show |
Series | Harden list_for_each_entry_rcu() and family | expand |
On Mon, Jul 15, 2019 at 10:37:02AM -0400, Joel Fernandes (Google) wrote: > list_for_each_entry_rcu now has support to check for RCU reader sections > as well as lock. Just use the support in it, instead of explictly > checking in the caller. > > Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> We need an ack from one of the subsystem maintainers on this one. Thanx, Paul > --- > kernel/workqueue.c | 10 ++-------- > 1 file changed, 2 insertions(+), 8 deletions(-) > > diff --git a/kernel/workqueue.c b/kernel/workqueue.c > index 601d61150b65..e882477ebf6e 100644 > --- a/kernel/workqueue.c > +++ b/kernel/workqueue.c > @@ -364,11 +364,6 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq); > !lockdep_is_held(&wq_pool_mutex), \ > "RCU or wq_pool_mutex should be held") > > -#define assert_rcu_or_wq_mutex(wq) \ > - RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ > - !lockdep_is_held(&wq->mutex), \ > - "RCU or wq->mutex should be held") > - > #define assert_rcu_or_wq_mutex_or_pool_mutex(wq) \ > RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ > !lockdep_is_held(&wq->mutex) && \ > @@ -425,9 +420,8 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq); > * ignored. > */ > #define for_each_pwq(pwq, wq) \ > - list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node) \ > - if (({ assert_rcu_or_wq_mutex(wq); false; })) { } \ > - else > + list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node, \ > + lock_is_held(&(wq->mutex).dep_map)) > > #ifdef CONFIG_DEBUG_OBJECTS_WORK > > -- > 2.22.0.510.g264f2c817a-goog >
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 601d61150b65..e882477ebf6e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -364,11 +364,6 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq); !lockdep_is_held(&wq_pool_mutex), \ "RCU or wq_pool_mutex should be held") -#define assert_rcu_or_wq_mutex(wq) \ - RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ - !lockdep_is_held(&wq->mutex), \ - "RCU or wq->mutex should be held") - #define assert_rcu_or_wq_mutex_or_pool_mutex(wq) \ RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ !lockdep_is_held(&wq->mutex) && \ @@ -425,9 +420,8 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq); * ignored. */ #define for_each_pwq(pwq, wq) \ - list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node) \ - if (({ assert_rcu_or_wq_mutex(wq); false; })) { } \ - else + list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node, \ + lock_is_held(&(wq->mutex).dep_map)) #ifdef CONFIG_DEBUG_OBJECTS_WORK
list_for_each_entry_rcu now has support to check for RCU reader sections as well as lock. Just use the support in it, instead of explictly checking in the caller. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> --- kernel/workqueue.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-)