On Tue, Jul 01, 2025 at 05:46:06PM -0700, Nicolin Chen wrote: > On Wed, Jul 02, 2025 at 12:14:28AM +0000, Pranjal Shrivastava wrote: > > Thus, coming back to the two initial points: > > > > 1) Issuing "non-invalidation" commands through .cache_invalidate could > > be confusing, I'm not asking to change the op name here, but if we > > plan to label it, let's label them as "Trapped commands" OR > > "non-accelerated" commands as you suggested. > > VCMDQ only accelerates limited invalidation commands, not all of > them: STE cache invalidation and CD cache invalidation commands > still go down to that op. >
Right, I'm just saying the "other" non-accelerated commands that are NOT invalidations also go down that op. So, if we add a comment, let's not call them "non-invalidation" commands. > > 2) The "FIXME" confusion: The comment in arm_vsmmu_cache_invalidate > > mentions we'd like to "fix" the issuing of commands through the main > > cmdq and instead like to group by "type", if that "type" is the queue > > type (which I assume it is because IOMMU_TYPE has to be arm-smmu-v3), > > I recall that FIXME is noted by Jason at that time. And it should > be interpreted as "group by opcode", IIUIC. I see.. I misunderstood that.. > > The thing is that for a host kernel that enabled in-kernel VCMDQs, > those trapped user commands can be just issued to the smmu->cmdq > or a vcmdq (picked via the get_secondary_cmdq impl_op). > Ohh.. so maybe some sort of a load balancing thing? > > what do we plan to do differently there, given that the op is only > > for trapped commands *have* to go through the main CMDQ? > > If we do something differently there, it could just do a one-time > get_secondary_cmdq call to pick a in-kernel vcmdq over smmu->cmdq > to fill in all the trapped commands. > Alright. > And this is not related to this series at all. Agreed, sorry for the confusion then.. I thought that the "type" meant the queue type.. I guess it's all done then. I have no further questions Thanks for the clarification! > > Nicolin Praan
