summaryrefslogtreecommitdiff
path: root/drivers/scsi/qla1280.c
diff options
context:
space:
mode:
authorWill Deacon <will.deacon@arm.com>2019-02-22 17:14:59 +0000
committerWill Deacon <will.deacon@arm.com>2019-04-08 12:01:02 +0100
commitfb24ea52f78e0d595852e09e3a55697c8f442189 (patch)
tree00ca29c7b0b8df6258a1ad1faf34f6e838ada26c /drivers/scsi/qla1280.c
parent949b8c72768e3a7c69d270962b8a142ee8deec1b (diff)
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/scsi/qla1280.c')
-rw-r--r--drivers/scsi/qla1280.c5
1 files changed, 0 insertions, 5 deletions
diff --git a/drivers/scsi/qla1280.c b/drivers/scsi/qla1280.c
index 6856dfdfa473..93acbc5094f0 100644
--- a/drivers/scsi/qla1280.c
+++ b/drivers/scsi/qla1280.c
@@ -3004,8 +3004,6 @@ qla1280_64bit_start_scsi(struct scsi_qla_host *ha, struct srb * sp)
sp->flags |= SRB_SENT;
ha->actthreads++;
WRT_REG_WORD(&reg->mailbox4, ha->req_ring_index);
- /* Enforce mmio write ordering; see comment in qla1280_isp_cmd(). */
- mmiowb();
out:
if (status)
@@ -3254,8 +3252,6 @@ qla1280_32bit_start_scsi(struct scsi_qla_host *ha, struct srb * sp)
sp->flags |= SRB_SENT;
ha->actthreads++;
WRT_REG_WORD(&reg->mailbox4, ha->req_ring_index);
- /* Enforce mmio write ordering; see comment in qla1280_isp_cmd(). */
- mmiowb();
out:
if (status)
@@ -3379,7 +3375,6 @@ qla1280_isp_cmd(struct scsi_qla_host *ha)
* See Documentation/driver-api/device-io.rst for more information.
*/
WRT_REG_WORD(&reg->mailbox4, ha->req_ring_index);
- mmiowb();
LEAVE("qla1280_isp_cmd");
}