diff options
author | John Garry <john.garry@huawei.com> | 2021-06-22 00:36:34 +0800 |
---|---|---|
committer | Will Deacon <will@kernel.org> | 2021-08-02 11:42:51 +0100 |
commit | 5c08c5acdc6ce46296a0f98d06896c818b8b34e0 (patch) | |
tree | a2d2cd537d663f2dcfee54dfc28252d3d006a9b3 /drivers | |
parent | ff1176468d368232b684f75e82563369208bc371 (diff) |
iommu/arm-smmu-v3: Remove some unneeded init in arm_smmu_cmdq_issue_cmdlist()
Members of struct "llq" will be zero-inited, apart from member max_n_shift.
But we write llq.val straight after the init, so it was pointless to zero
init those other members. As such, separately init member max_n_shift
only.
In addition, struct "head" is initialised to "llq" only so that member
max_n_shift is set. But that member is never referenced for "head", so
remove any init there.
Removing these initializations is seen as a small performance optimisation,
as this code is (very) hot path.
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1624293394-202509-1-git-send-email-john.garry@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 235f9bdaeaf2..952291840c76 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -733,11 +733,11 @@ static int arm_smmu_cmdq_issue_cmdlist(struct arm_smmu_device *smmu, unsigned long flags; bool owner; struct arm_smmu_cmdq *cmdq = &smmu->cmdq; - struct arm_smmu_ll_queue llq = { - .max_n_shift = cmdq->q.llq.max_n_shift, - }, head = llq; + struct arm_smmu_ll_queue llq, head; int ret = 0; + llq.max_n_shift = cmdq->q.llq.max_n_shift; + /* 1. Allocate some space in the queue */ local_irq_save(flags); llq.val = READ_ONCE(cmdq->q.llq.val); |