This patchset allows for setup_rfi_flush() to be called again
after PowerVM LPM (live partition mobility) aka LPAR migration,
in order to possibly switch to a different flush method.
The patches are mostly from Michael Ellerman, I have rebased to
powerpc/linux.git merge branch as of commit 249d7ba (March 12th),
and added one extra commit to force init of fallback flush area
on pseries.
Testing:
-------
I've disabled most code in the LPM functions migration_store()
and post_mobility_fixup() to just reach pseries_setup_rfi_flush(),
and modified pseries_setup_rfi_flush() a few times to fake the
first and non-first calls to either enable instructions or the
fallback flush method, to cover all 4 possible scenarios.
Case 1) fallback -> fallback
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using fallback displacement flush
[ 0.000000] rfi-flush: patched 8 locations
# echo > /sys/kernel/mobility/migration
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using fallback displacement flush
[ 0.000000] rfi-flush: patched 8 locations
[ 20.583029] rfi-flush: Using fallback displacement flush
[ 20.583038] rfi-flush: patched 8 locations
Case 2) instructions -> fallback
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using ori type flush
[ 0.000000] rfi-flush: Using mttrig type flush
[ 0.000000] rfi-flush: patched 8 locations
# echo > /sys/kernel/mobility/migration
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using ori type flush
[ 0.000000] rfi-flush: Using mttrig type flush
[ 0.000000] rfi-flush: patched 8 locations
[ 36.023759] rfi-flush: Using fallback displacement flush
[ 36.023764] rfi-flush: patched 8 locations
Case 3) fallback -> instructions
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using fallback displacement flush
[ 0.000000] rfi-flush: patched 8 locations
# echo > /sys/kernel/mobility/migration
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using fallback displacement flush
[ 0.000000] rfi-flush: patched 8 locations
[ 23.373037] rfi-flush: Using ori type flush
[ 23.373039] rfi-flush: Using mttrig type flush
[ 23.373044] rfi-flush: patched 8 locations
Case 4) instructions -> instructions
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using ori type flush
[ 0.000000] rfi-flush: Using mttrig type flush
[ 0.000000] rfi-flush: patched 8 locations
# echo > /sys/kernel/mobility/migration
# dmesg | grep rfi-flush
[ 0.000000] rfi-flush: Using ori type flush
[ 0.000000] rfi-flush: Using mttrig type flush
[ 0.000000] rfi-flush: patched 8 locations
[ 23.243564] rfi-flush: Using ori type flush
[ 23.243566] rfi-flush: Using mttrig type flush
[ 23.243570] rfi-flush: patched 8 locations
Mauricio Faria de Oliveira (1):
rfi-flush: Allow pseries to force init of fallback flush area
Michael Ellerman (3):
rfi-flush: Move the logic to avoid a redo into the debugfs code
rfi-flush: Make it possible to call setup_rfi_flush() again
rfi-flush: Call setup_rfi_flush() after LPM migration
arch/powerpc/include/asm/setup.h | 2 +-
arch/powerpc/kernel/setup_64.c | 22 +++++++++++++++-------
arch/powerpc/platforms/powernv/setup.c | 3 ++-
arch/powerpc/platforms/pseries/mobility.c | 3 +++
arch/powerpc/platforms/pseries/pseries.h | 2 ++
arch/powerpc/platforms/pseries/setup.c | 6 +++---
6 files changed, 26 insertions(+), 12 deletions(-)
--
2.7.4
