powerpc/pseries: Kill all prefetch streams on context switch
On context switch, we should have no prefetch streams leak from one
userspace process to another. This frees up prefetch resources for the
next process.
Based on patch from Milton Miller.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index cea8496..2f1b6c5 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -523,6 +523,17 @@
#define PPC440EP_ERR42
#endif
+/* The following stops all load and store data streams associated with stream
+ * ID (ie. streams created explicitly). The embedded and server mnemonics for
+ * dcbt are different so we use machine "power4" here explicitly.
+ */
+#define DCBT_STOP_ALL_STREAM_IDS(scratch) \
+.machine push ; \
+.machine "power4" ; \
+ lis scratch,0x60000000@h; \
+ dcbt r0,scratch,0b01010; \
+.machine pop
+
/*
* toreal/fromreal/tophys/tovirt macros. 32-bit BookE makes them
* keep the address intact to be compatible with code shared with