Messages in this thread | | | Date | Thu, 17 Jan 2019 16:31:32 +0100 | From | Andrea Parri <> | Subject | Re: [PATCH] afs: Add missing memory barriers in afs_manage_cell() |
| |
On Mon, Nov 26, 2018 at 05:44:12PM +0100, Andrea Parri wrote: > As the comments for wake_up_bit() and waitqueue_active() point out, > the barriers are needed to order the clearing of the _FL_NOT_READY > bit and the waitqueue_active() load; match the implicit barrier in > prepare_to_wait(). > > Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Hi David, do you have any feedback on this?
Andrea
> --- > fs/afs/cell.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/afs/cell.c b/fs/afs/cell.c > index cf445dbd5f2e0..a9488abe56029 100644 > --- a/fs/afs/cell.c > +++ b/fs/afs/cell.c > @@ -637,6 +637,7 @@ static void afs_manage_cell(struct work_struct *work) > cell->state = AFS_CELL_ACTIVE; > smp_wmb(); > clear_bit(AFS_CELL_FL_NOT_READY, &cell->flags); > + smp_mb__after_atomic(); /* see comment for wake_up_bit() */ > wake_up_bit(&cell->flags, AFS_CELL_FL_NOT_READY); > goto again; > > @@ -678,6 +679,7 @@ static void afs_manage_cell(struct work_struct *work) > cell->state = AFS_CELL_ACTIVE; > smp_wmb(); > clear_bit(AFS_CELL_FL_NOT_READY, &cell->flags); > + smp_mb__after_atomic(); /* see comment for wake_up_bit() */ > wake_up_bit(&cell->flags, AFS_CELL_FL_NOT_READY); > _leave(" [deact->act]"); > return; > -- > 2.17.1 >
| |