[POWERPC] irqtrace support for 64-bit powerpc
This adds the low level irq tracing hooks to the powerpc architecture
needed to enable full lockdep functionality.
This is partly based on Johannes Berg's initial version. I removed
the asm trampoline that isn't needed (thus improving performance) and
modified all sorts of bits and pieces, reworking most of the assembly,
etc...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 1301984..c0db5b7 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -30,6 +30,7 @@
#include <asm/firmware.h>
#include <asm/bug.h>
#include <asm/ptrace.h>
+#include <asm/irqflags.h>
/*
* System calls.
@@ -89,6 +90,14 @@
addi r9,r1,STACK_FRAME_OVERHEAD
ld r11,exception_marker@toc(r2)
std r11,-16(r9) /* "regshere" marker */
+#ifdef CONFIG_TRACE_IRQFLAGS
+ bl .trace_hardirqs_on
+ REST_GPR(0,r1)
+ REST_4GPRS(3,r1)
+ REST_2GPRS(7,r1)
+ addi r9,r1,STACK_FRAME_OVERHEAD
+ ld r12,_MSR(r1)
+#endif /* CONFIG_TRACE_IRQFLAGS */
li r10,1
stb r10,PACASOFTIRQEN(r13)
stb r10,PACAHARDIRQEN(r13)
@@ -103,7 +112,7 @@
b hardware_interrupt_entry
2:
END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
-#endif
+#endif /* CONFIG_PPC_ISERIES */
mfmsr r11
ori r11,r11,MSR_EE
mtmsrd r11,1
@@ -505,6 +514,10 @@
li r3,0
stb r3,PACASOFTIRQEN(r13) /* ensure we are soft-disabled */
+#ifdef CONFIG_TRACE_IRQFLAGS
+ bl .trace_hardirqs_off
+ mfmsr r10
+#endif
ori r10,r10,MSR_EE
mtmsrd r10 /* hard-enable again */
addi r3,r1,STACK_FRAME_OVERHEAD
@@ -513,7 +526,7 @@
4:
END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
#endif
- stb r5,PACASOFTIRQEN(r13)
+ TRACE_AND_RESTORE_IRQ(r5);
/* extract EE bit and use it to restore paca->hard_enabled */
ld r3,_MSR(r1)
@@ -581,6 +594,16 @@
bne restore
/* here we are preempting the current task */
1:
+#ifdef CONFIG_TRACE_IRQFLAGS
+ bl .trace_hardirqs_on
+ /* Note: we just clobbered r10 which used to contain the previous
+ * MSR before the hard-disabling done by the caller of do_work.
+ * We don't have that value anymore, but it doesn't matter as
+ * we will hard-enable unconditionally, we can just reload the
+ * current MSR into r10
+ */
+ mfmsr r10
+#endif /* CONFIG_TRACE_IRQFLAGS */
li r0,1
stb r0,PACASOFTIRQEN(r13)
stb r0,PACAHARDIRQEN(r13)