powerpc: Add helper functions for transactional memory context switching

mikey · ozbenh · commit 98ae22e15b43 · 2013-02-15T16:58:52.000+11:00
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 &lt;matt@ozlabs.org&gt;
Signed-off-by: Michael Neuling &lt;mikey@neuling.org&gt;
Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
diff --git 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
diff --git a/arch/powerpc/include/asm/tm.h b/arch/powerpc/include/asm/tm.h
@@ -0,0 +1,20 @@
+/*
+ * Transactional memory support routines to reclaim and recheckpoint
+ * transactional process state.
+ *
+ * Copyright 2012 Matt Evans & Michael Neuling, IBM Corporation.
+ */
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+extern void do_load_up_transact_fpu(struct thread_struct *thread);
+extern void do_load_up_transact_altivec(struct thread_struct *thread);
+#endif
+
+extern void tm_enable(void);
+extern void tm_reclaim(struct thread_struct *thread,
+		       unsigned long orig_msr, uint8_t cause);
+extern void tm_recheckpoint(struct thread_struct *thread,
+			    unsigned long orig_msr);
+extern void tm_abort(uint8_t cause);
+extern void tm_save_sprs(struct thread_struct *thread);
+extern void tm_restore_sprs(struct thread_struct *thread);
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
@@ -121,6 +121,8 @@ ifneq ($(CONFIG_PPC_INDIRECT_IO),y)
 obj-y				+= iomap.o
 endif
 
+obj64-$(CONFIG_PPC_TRANSACTIONAL_MEM)	+= tm.o
+
 obj-$(CONFIG_PPC64)		+= $(obj64-y)
 obj-$(CONFIG_PPC32)		+= $(obj32-y)
 
diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S

Original file line number	Diff line number	Diff line change
`@@ -797,7 +797,7 @@`
`797`	`797`	`* HV mode in which case it is HSPRG0`
`798`	`798`	`*`
`799`	`799`	`* 64-bit server:`
`800`		`- * - SPRG0 unused (reserved for HV on Power4)`
	`800`	`+ * - SPRG0 scratch for TM recheckpoint/reclaim (reserved for HV on Power4)`
`801`	`801`	`* - SPRG2 scratch for exception vectors`
`802`	`802`	`* - SPRG3 CPU and NUMA node for VDSO getcpu (user visible)`
`803`	`803`	`* - HSPRG0 stores PACA in HV mode`