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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Sep 2025 02:03:43.1817 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: deab1174-f6d7-4f77-4178-08ddf00e44ee X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.118.233];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: SN1PEPF0002636B.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB5713 On Wed, Sep 10, 2025 at 08:49:52AM +1000, Balbir Singh wrote: > On 9/9/25 15:42, Nicolin Chen wrote: > > On Tue, Sep 09, 2025 at 01:16:11PM +1000, Balbir Singh wrote: > >> On 9/9/25 09:26, Nicolin Chen wrote: > >>> None of the callers of arm_smmu_cmdq_batch_submit() cares about the batch > >>> after a submission. So, it'll be certainly safe to nuke the cmds->num, at > >>> least upon a successful one. This will ease a bit a wrapper function, for > >>> the new arm_smmu_invs structure. > >>> > >>> Signed-off-by: Nicolin Chen > >>> --- > >>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++++++-- > >>> 1 file changed, 8 insertions(+), 2 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 2a8b46b948f05..cccf8f52ee0d5 100644 > >>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > >>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > >>> @@ -974,11 +974,17 @@ static void arm_smmu_cmdq_batch_add(struct arm_smmu_device *smmu, > >>> cmds->num++; > >>> } > >>> > >>> +/* Clears cmds->num after a successful submission */ > >>> static int arm_smmu_cmdq_batch_submit(struct arm_smmu_device *smmu, > >>> struct arm_smmu_cmdq_batch *cmds) > >>> { > >> > >> Nit: arm_smmu_cmdq_batch_submit_clear()? > > > > Probably not. There is no particular point in highlighting it in > > the function name, as there is no use case wanting an uncleared > > version. > > I did not suggest we need an uncleared version, I suggested the change > in name to highlight that the function has a side-effect of clearing > the cmds->num No caller cares about the "side effect"... Nicolin