diff options
author | Will Deacon <will.deacon@arm.com> | 2019-02-22 17:14:59 +0000 |
---|---|---|
committer | Will Deacon <will.deacon@arm.com> | 2019-04-08 12:01:02 +0100 |
commit | fb24ea52f78e0d595852e09e3a55697c8f442189 (patch) | |
tree | 00ca29c7b0b8df6258a1ad1faf34f6e838ada26c /drivers/infiniband/hw/mthca/mthca_cq.c | |
parent | 949b8c72768e3a7c69d270962b8a142ee8deec1b (diff) | |
download | linux-fb24ea52f78e0d595852e09e3a55697c8f442189.tar.bz2 |
drivers: Remove explicit invocations of mmiowb()
mmiowb() is now implied by spin_unlock() on architectures that require
it, so there is no reason to call it from driver code. This patch was
generated using coccinelle:
@mmiowb@
@@
- mmiowb();
and invoked as:
$ for d in drivers include/linux/qed sound; do \
spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done
NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation. If you've ended up bisecting to this commit, you can
reintroduce the mmiowb() calls using wmb() instead, which should restore
the old behaviour on all architectures other than some esoteric ia64
systems.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/infiniband/hw/mthca/mthca_cq.c')
-rw-r--r-- | drivers/infiniband/hw/mthca/mthca_cq.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/drivers/infiniband/hw/mthca/mthca_cq.c b/drivers/infiniband/hw/mthca/mthca_cq.c index a6531ffe29a6..877a6daffa98 100644 --- a/drivers/infiniband/hw/mthca/mthca_cq.c +++ b/drivers/infiniband/hw/mthca/mthca_cq.c @@ -211,11 +211,6 @@ static inline void update_cons_index(struct mthca_dev *dev, struct mthca_cq *cq, mthca_write64(MTHCA_TAVOR_CQ_DB_INC_CI | cq->cqn, incr - 1, dev->kar + MTHCA_CQ_DOORBELL, MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock)); - /* - * Make sure doorbells don't leak out of CQ spinlock - * and reach the HCA out of order: - */ - mmiowb(); } } |