powerpc: Add helper functions for transactional memory context switching
Here we add the helper functions to be used when context switching. These
allow us to fully reclaim and recheckpoint a transaction.
We introduce a new paca field called tm_scratch to help us store away register
values when doing the low level tm reclaim register save.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 7844c28..eee2a609 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -797,7 +797,7 @@
* HV mode in which case it is HSPRG0
*
* 64-bit server:
- * - SPRG0 unused (reserved for HV on Power4)
+ * - SPRG0 scratch for TM recheckpoint/reclaim (reserved for HV on Power4)
* - SPRG2 scratch for exception vectors
* - SPRG3 CPU and NUMA node for VDSO getcpu (user visible)
* - HSPRG0 stores PACA in HV mode