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. 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 > > >
