On Wed, 2022-02-23 at 19:38 +1000, Nicholas Piggin wrote: > Excerpts from Haren Myneni's message of February 20, 2022 6:04 am: > > Virtual Accelerator Switchboard (VAS) is an engine stays on the > > chip. So all windows opened on a specific engine belongs to VAS > > the chip. > > The problem is more that PAPR does not virtualise the VAS windows, > right? That's a whole other gripe but nothing you can do about it > here.
Yes, There is no virtualization with VAS windows and they are specific to the chip. > > Thanks, > Nick > > > The hypervisor expects the partition to close all > > active windows on the sources system and reopen them after > > migration on the destination machine. > > > > This patch series adds VAS support with the partition migration. > > When the migration initiates, the VAS migration handler will be > > invoked before pseries_suspend() to close all active windows and > > mark them in-active with VAS_WIN_MIGRATE_CLOSE status. Whereas > > this migration handler is called after migration to reopen all > > windows which has VAS_WIN_MIGRATE_CLOSE status and make them > > active again. The user space gets paste instruction failure > > when it sends requests on these in-active windows. > > > > These patches depend on VAS/DLPAR support patch series > > > > Changes in v2: > > - Added new patch "Define global hv_cop_caps struct" to eliminate > > memory allocation failure during migration (suggestion by > > Nathan Lynch) > > > > Changes in v3: > > - Rebase on 5.17-rc4 > > - Naming changes for VAS capability struct elemets based on the V4 > > DLPAR > > support patch series. > > > > Haren Myneni (4): > > powerpc/pseries/vas: Define global hv_cop_caps struct > > powerpc/pseries/vas: Modify reconfig open/close functions for > > migration > > powerpc/pseries/vas: Add VAS migration handler > > powerpc/pseries/vas: Disable window open during migration > > > > arch/powerpc/include/asm/vas.h | 2 + > > arch/powerpc/platforms/pseries/mobility.c | 5 + > > arch/powerpc/platforms/pseries/vas.c | 234 +++++++++++++++++- > > ---- > > arch/powerpc/platforms/pseries/vas.h | 6 + > > 4 files changed, 201 insertions(+), 46 deletions(-) > > > > -- > > 2.27.0 > > > > > >
