On Tue, Apr 29, 2025 at 06:10:31PM +0000, Pranjal Shrivastava wrote: > On Tue, Apr 29, 2025 at 08:28:01AM +0000, Pranjal Shrivastava wrote: > > On Mon, Apr 28, 2025 at 03:44:08PM -0700, Nicolin Chen wrote: > > > On Mon, Apr 28, 2025 at 09:34:05PM +0000, Pranjal Shrivastava wrote: > > > > On Fri, Apr 25, 2025 at 10:58:05PM -0700, Nicolin Chen wrote: > > [...] > > > > IIUC, one vintf can have multiple lvcmdqs and looking at the series > > > > it looks like the vcmdq_alloc allocates a single lvcmdq. Is the plan to > > > > dedicate one lvcmdq to per VM? Which means VMs can share a vintf? > > > > > > VINTF is a vSMMU instance per SMMU. Each VINTF can have multiple > > > LVCMDQs. Each vCMDQ is allocated per IOMMUFD_CMD_VCMDQ_ALLOC. In > > > other word, VM can issue multiple IOMMUFD_CMD_VCMDQ_ALLOC calls > > > for each VTINF/vSMMU. > > > > > > > Ack. I'm just wondering why would a single VM want more than one vCMDQ > > per vSMMU? > > [...] > > I guess the only thing on this patch from me was to understand why > would a single VM want more than one vCMDQ per vSMMU? (Just curious to > know :) )
It gives some perf gain since it has two portals to fill commands. Nicolin
