powerpc/tracing: TRACE_WITH_FRAME_BUFFER creates invalid stack frames
[cascardo/linux.git] / arch / powerpc / include / asm / irqflags.h
1 /*
2  * IRQ flags handling
3  */
4 #ifndef _ASM_IRQFLAGS_H
5 #define _ASM_IRQFLAGS_H
6
7 #ifndef __ASSEMBLY__
8 /*
9  * Get definitions for arch_local_save_flags(x), etc.
10  */
11 #include <asm/hw_irq.h>
12
13 #else
14 #ifdef CONFIG_TRACE_IRQFLAGS
15 #ifdef CONFIG_IRQSOFF_TRACER
16 /*
17  * Since the ftrace irqsoff latency trace checks CALLER_ADDR1,
18  * which is the stack frame here, we need to force a stack frame
19  * in case we came from user space.
20  */
21 #define TRACE_WITH_FRAME_BUFFER(func)           \
22         mflr    r0;                             \
23         stdu    r1, -STACK_FRAME_OVERHEAD(r1);  \
24         std     r0, 16(r1);                     \
25         stdu    r1, -STACK_FRAME_OVERHEAD(r1);  \
26         bl func;                                \
27         ld      r1, 0(r1);                      \
28         ld      r1, 0(r1);
29 #else
30 #define TRACE_WITH_FRAME_BUFFER(func)           \
31         bl func;
32 #endif
33
34 /*
35  * Most of the CPU's IRQ-state tracing is done from assembly code; we
36  * have to call a C function so call a wrapper that saves all the
37  * C-clobbered registers.
38  */
39 #define TRACE_ENABLE_INTS       TRACE_WITH_FRAME_BUFFER(trace_hardirqs_on)
40 #define TRACE_DISABLE_INTS      TRACE_WITH_FRAME_BUFFER(trace_hardirqs_off)
41
42 /*
43  * This is used by assembly code to soft-disable interrupts first and
44  * reconcile irq state.
45  */
46 #define RECONCILE_IRQ_STATE(__rA, __rB)         \
47         lbz     __rA,PACASOFTIRQEN(r13);        \
48         lbz     __rB,PACAIRQHAPPENED(r13);      \
49         cmpwi   cr0,__rA,0;                     \
50         li      __rA,0;                         \
51         ori     __rB,__rB,PACA_IRQ_HARD_DIS;    \
52         stb     __rB,PACAIRQHAPPENED(r13);      \
53         beq     44f;                            \
54         stb     __rA,PACASOFTIRQEN(r13);        \
55         TRACE_DISABLE_INTS;                     \
56 44:
57
58 #else
59 #define TRACE_ENABLE_INTS
60 #define TRACE_DISABLE_INTS
61
62 #define RECONCILE_IRQ_STATE(__rA, __rB)         \
63         lbz     __rA,PACAIRQHAPPENED(r13);      \
64         li      __rB,0;                         \
65         ori     __rA,__rA,PACA_IRQ_HARD_DIS;    \
66         stb     __rB,PACASOFTIRQEN(r13);        \
67         stb     __rA,PACAIRQHAPPENED(r13)
68 #endif
69 #endif
70
71 #endif