This series aims to improve the pseries-specific partition migration
and hibernation implementation, part of which has been living in
kernel/rtas.c. Most of that code is eliminated or moved to
platforms/pseries, and the following major functional changes are
made:
- Use stop_machine() instead of on_each_cpu() to avoid deadlock in the
join/suspend sequence.
- Retry the join/suspend sequence on errors that are likely to be
transient. This is a mitigation for the fact that drivers currently
have no way to prepare for an impending partition suspension,
sometimes resulting in a virtual adapter being in a state which
causes the platform to fail the suspend call.
- Request cancellation of the migration via H_VASI_SIGNAL if Linux is
going to error out of the suspend attempt. This allows the
management console and other entities to promptly clean up their
operations instead of relying on long timeouts to fail the
migration.
- Little-endian users of ibm,suspend-me, ibm,update-nodes and
ibm,update-properties via sys_rtas are blocked when
CONFIG_PPC_RTAS_FILTERS is enabled.
- Legacy user space code (drmgr) historically has driven the migration
process by using sys_rtas to separately call ibm,suspend-me,
ibm,activate-firmware, and ibm,update-nodes/properties, in that
order. With these changes, when sys_rtas() dispatches
ibm,suspend-me, the kernel performs the device tree update and
firmware activation before returning. This is more reliable, and
drmgr does not seem bothered by it.
- If the H_VASI_STATE hcall is absent, the implementation proceeds
with the suspend instead of erroring out. This allows us to exercise
these code paths in QEMU.
Nathan Lynch (29):
powerpc/rtas: move rtas_call_reentrant() out of pseries guards
powerpc/rtas: prevent suspend-related sys_rtas use on LE
powerpc/rtas: complete ibm,suspend-me status codes
powerpc/rtas: rtas_ibm_suspend_me -> rtas_ibm_suspend_me_unsafe
powerpc/rtas: add rtas_ibm_suspend_me()
powerpc/rtas: add rtas_activate_firmware()
powerpc/hvcall: add token and codes for H_VASI_SIGNAL
powerpc/pseries/mobility: don't error on absence of ibm,update-nodes
powerpc/pseries/mobility: add missing break to default case
powerpc/pseries/mobility: error message improvements
powerpc/pseries/mobility: use rtas_activate_firmware() on resume
powerpc/pseries/mobility: extract VASI session polling logic
powerpc/pseries/mobility: use stop_machine for join/suspend
powerpc/pseries/mobility: signal suspend cancellation to platform
powerpc/pseries/mobility: retry partition suspend after error
powerpc/rtas: dispatch partition migration requests to pseries
powerpc/rtas: remove rtas_ibm_suspend_me_unsafe()
powerpc/pseries/hibernation: drop pseries_suspend_begin() from suspend
ops
powerpc/pseries/hibernation: pass stream id via function arguments
powerpc/pseries/hibernation: remove pseries_suspend_cpu()
powerpc/machdep: remove suspend_disable_cpu()
powerpc/rtas: remove rtas_suspend_cpu()
powerpc/pseries/hibernation: switch to rtas_ibm_suspend_me()
powerpc/rtas: remove unused rtas_suspend_last_cpu()
powerpc/pseries/hibernation: remove redundant cacheinfo update
powerpc/pseries/hibernation: perform post-suspend fixups later
powerpc/pseries/hibernation: remove prepare_late() callback
powerpc/rtas: remove unused rtas_suspend_me_data
powerpc/pseries/mobility: refactor node lookup during DT update
arch/powerpc/include/asm/hvcall.h | 9 +
arch/powerpc/include/asm/machdep.h | 1 -
arch/powerpc/include/asm/rtas-types.h | 8 -
arch/powerpc/include/asm/rtas.h | 13 +-
arch/powerpc/kernel/rtas.c | 245 ++++++---------
arch/powerpc/platforms/pseries/mobility.c | 361 ++++++++++++++++++----
arch/powerpc/platforms/pseries/suspend.c | 79 +----
7 files changed, 420 insertions(+), 296 deletions(-)
--
2.25.4
