diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2021-11-23 19:52:15 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-11-24 21:09:01 +1100 |
| commit | 022ecb960c89faad42ff0b417a71d9255dd115a3 (patch) | |
| tree | a47d026ae9a2b4d543edc30a283771c4c50b279e /arch/powerpc/kernel/process.c | |
| parent | a3e18ca8ab6f7f2260978f0a3842845414d799c0 (diff) | |
KVM: PPC: Book3S HV P9: Demand fault TM facility registers
Use HFSCR facility disabling to implement demand faulting for TM, with
a hysteresis counter similar to the load_fp etc counters in context
switching that implement the equivalent demand faulting for userspace
facilities.
This speeds up guest entry/exit by avoiding the register save/restore
when a guest is not frequently using them. When a guest does use them
often, there will be some additional demand fault overhead, but these
are not commonly used facilities.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-38-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kernel/process.c')
0 files changed, 0 insertions, 0 deletions