Merge tag 'drm-fixes-for-v4.13-rc1' of git://people.freedesktop.org/~airlied/linux

[sfrench/cifs-2.6.git] / arch / arm / kernel / entry-ftrace.S

diff --git a/arch/arm/kernel/entry-ftrace.S b/arch/arm/kernel/entry-ftrace.S
index c73c4030ca5dd549e3b102d4a77f493e1549e02d..efcd9f25a14bfbc13eeea1108a7d47f73d168604 100644 (file)
--- a/arch/arm/kernel/entry-ftrace.S
+++ b/arch/arm/kernel/entry-ftrace.S
@@ -92,12 +92,95 @@
 2:     mcount_exit
 .endm
 
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+
+.macro __ftrace_regs_caller
+
+       sub     sp, sp, #8      @ space for PC and CPSR OLD_R0,
+                               @ OLD_R0 will overwrite previous LR
+
+       add     ip, sp, #12     @ move in IP the value of SP as it was
+                               @ before the push {lr} of the mcount mechanism
+
+       str     lr, [sp, #0]    @ store LR instead of PC
+
+       ldr     lr, [sp, #8]    @ get previous LR
+
+       str     r0, [sp, #8]    @ write r0 as OLD_R0 over previous LR
+
+       stmdb   sp!, {ip, lr}
+       stmdb   sp!, {r0-r11, lr}
+
+       @ stack content at this point:
+       @ 0  4          48   52       56            60   64    68       72
+       @ R0 | R1 | ... | LR | SP + 4 | previous LR | LR | PSR | OLD_R0 |
+
+       mov r3, sp                              @ struct pt_regs*
+
+       ldr r2, =function_trace_op
+       ldr r2, [r2]                            @ pointer to the current
+                                               @ function tracing op
+
+       ldr     r1, [sp, #S_LR]                 @ lr of instrumented func
+
+       ldr     lr, [sp, #S_PC]                 @ get LR
+
+       mcount_adjust_addr      r0, lr          @ instrumented function
+
+       .globl ftrace_regs_call
+ftrace_regs_call:
+       bl      ftrace_stub
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       .globl ftrace_graph_regs_call
+ftrace_graph_regs_call:
+       mov     r0, r0
+#endif
+
+       @ pop saved regs
+       ldmia   sp!, {r0-r12}                   @ restore r0 through r12
+       ldr     ip, [sp, #8]                    @ restore PC
+       ldr     lr, [sp, #4]                    @ restore LR
+       ldr     sp, [sp, #0]                    @ restore SP
+       mov     pc, ip                          @ return
+.endm
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.macro __ftrace_graph_regs_caller
+
+       sub     r0, fp, #4              @ lr of instrumented routine (parent)
+
+       @ called from __ftrace_regs_caller
+       ldr     r1, [sp, #S_PC]         @ instrumented routine (func)
+       mcount_adjust_addr      r1, r1
+
+       mov     r2, fp                  @ frame pointer
+       bl      prepare_ftrace_return
+
+       @ pop registers saved in ftrace_regs_caller
+       ldmia   sp!, {r0-r12}                   @ restore r0 through r12
+       ldr     ip, [sp, #8]                    @ restore PC
+       ldr     lr, [sp, #4]                    @ restore LR
+       ldr     sp, [sp, #0]                    @ restore SP
+       mov     pc, ip                          @ return
+
+.endm
+#endif
+#endif
+
 .macro __ftrace_caller suffix
        mcount_enter
 
        mcount_get_lr   r1                      @ lr of instrumented func
        mcount_adjust_addr      r0, lr          @ instrumented function
 
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+       ldr r2, =function_trace_op
+       ldr r2, [r2]                            @ pointer to the current
+                                               @ function tracing op
+       mov r3, #0                              @ regs is NULL
+#endif
+
        .globl ftrace_call\suffix
 ftrace_call\suffix:
        bl      ftrace_stub
@@ -212,6 +295,15 @@ UNWIND(.fnstart)
        __ftrace_caller
 UNWIND(.fnend)
 ENDPROC(ftrace_caller)
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ENTRY(ftrace_regs_caller)
+UNWIND(.fnstart)
+       __ftrace_regs_caller
+UNWIND(.fnend)
+ENDPROC(ftrace_regs_caller)
+#endif
+
 #endif
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -220,6 +312,14 @@ UNWIND(.fnstart)
        __ftrace_graph_caller
 UNWIND(.fnend)
 ENDPROC(ftrace_graph_caller)
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ENTRY(ftrace_graph_regs_caller)
+UNWIND(.fnstart)
+       __ftrace_graph_regs_caller
+UNWIND(.fnend)
+ENDPROC(ftrace_graph_regs_caller)
+#endif
 #endif
 
 .purgem mcount_enter