From d3e75ff14bc1453c4762428395aac9953a023efc Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Fri, 9 Jan 2009 11:29:46 +0800 Subject: ftrace, ia64: IA64 static ftrace support IA64 ftrace suppport. In IA64, below code will be added in each function if -pg is enabled. alloc r40=ar.pfs,12,8,0 mov r43=r0;; mov r42=b0 mov r41=r1 nop.i 0x0 br.call.sptk.many b0 = _mcount;; Signed-off-by: Shaohua Li Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- arch/ia64/kernel/entry.S | 49 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) (limited to 'arch/ia64/kernel/entry.S') diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S index d435f4a7a96..c2f7d798e2a 100644 --- a/arch/ia64/kernel/entry.S +++ b/arch/ia64/kernel/entry.S @@ -47,6 +47,7 @@ #include #include #include +#include #include "minstate.h" @@ -1404,6 +1405,54 @@ GLOBAL_ENTRY(unw_init_running) br.ret.sptk.many rp END(unw_init_running) +#ifdef CONFIG_FUNCTION_TRACER +GLOBAL_ENTRY(_mcount) + movl r2 = ftrace_stub + movl r3 = ftrace_trace_function;; + ld8 r3 = [r3];; + ld8 r3 = [r3];; + cmp.eq p7,p0 = r2, r3 +(p7) br.sptk.many ftrace_stub + ;; + + alloc loc0 = ar.pfs, 4, 4, 2, 0 + ;; + mov loc1 = b0 + mov out0 = b0 + mov loc2 = r8 + mov loc3 = r15 + ;; + adds out0 = -MCOUNT_INSN_SIZE, out0 + mov out1 = in2 + mov b6 = r3 + + br.call.sptk.many b0 = b6 + ;; + mov ar.pfs = loc0 + mov b0 = loc1 + mov r8 = loc2 + mov r15 = loc3 + br ftrace_stub + ;; +END(_mcount) + +GLOBAL_ENTRY(ftrace_stub) + mov r3 = b0 + movl r2 = _mcount_ret_helper + ;; + mov b6 = r2 + mov b7 = r3 + br.ret.sptk.many b6 + +_mcount_ret_helper: + mov b0 = r42 + mov r1 = r41 + mov ar.pfs = r40 + br b7 +END(ftrace_stub) + +#endif /* CONFIG_FUNCTION_TRACER */ + .rodata .align 8 .globl sys_call_table -- cgit v1.2.3 From a14a07b8018b714e03a39ff2180c66e307ef4238 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Fri, 9 Jan 2009 11:29:49 +0800 Subject: ftrace, ia64: IA64 dynamic ftrace support IA64 dynamic ftrace support. The original _mcount stub for each function is like: alloc r40=ar.pfs,12,8,0 mov r43=r0;; mov r42=b0 mov r41=r1 nop.i 0x0 br.call.sptk.many b0 = _mcount;; The patch convert it to below for nop: [MII] nop.m 0x0 mov r3=ip nop.i 0x0 [MLX] nop.m 0x0 nop.x 0x0;; This isn't completely nop, as there is one instuction 'mov r3=ip', but it should be light and harmless for code follow it. And below is for call [MII] nop.m 0x0 mov r3=ip nop.i 0x0 [MLX] nop.m 0x0 brl.many .;; In this way, only one instruction is changed to convert code between nop and call. This should meet dyn-ftrace's requirement. But this requires CPU support brl instruction, so dyn-ftrace isn't supported for old Itanium system. Assume there are quite few such old system running. Signed-off-by: Shaohua Li Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- arch/ia64/kernel/entry.S | 51 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'arch/ia64/kernel/entry.S') diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S index c2f7d798e2a..e0be92a6abb 100644 --- a/arch/ia64/kernel/entry.S +++ b/arch/ia64/kernel/entry.S @@ -1406,6 +1406,56 @@ GLOBAL_ENTRY(unw_init_running) END(unw_init_running) #ifdef CONFIG_FUNCTION_TRACER +#ifdef CONFIG_DYNAMIC_FTRACE +GLOBAL_ENTRY(_mcount) + br ftrace_stub +END(_mcount) + +.here: + br.ret.sptk.many b0 + +GLOBAL_ENTRY(ftrace_caller) + alloc out0 = ar.pfs, 8, 0, 4, 0 + mov out3 = r0 + ;; + mov out2 = b0 + add r3 = 0x20, r3 + mov out1 = r1; + br.call.sptk.many b0 = ftrace_patch_gp + //this might be called from module, so we must patch gp +ftrace_patch_gp: + movl gp=__gp + mov b0 = r3 + ;; +.global ftrace_call; +ftrace_call: +{ + .mlx + nop.m 0x0 + movl r3 = .here;; +} + alloc loc0 = ar.pfs, 4, 4, 2, 0 + ;; + mov loc1 = b0 + mov out0 = b0 + mov loc2 = r8 + mov loc3 = r15 + ;; + adds out0 = -MCOUNT_INSN_SIZE, out0 + mov out1 = in2 + mov b6 = r3 + + br.call.sptk.many b0 = b6 + ;; + mov ar.pfs = loc0 + mov b0 = loc1 + mov r8 = loc2 + mov r15 = loc3 + br ftrace_stub + ;; +END(ftrace_caller) + +#else GLOBAL_ENTRY(_mcount) movl r2 = ftrace_stub movl r3 = ftrace_trace_function;; @@ -1435,6 +1485,7 @@ GLOBAL_ENTRY(_mcount) br ftrace_stub ;; END(_mcount) +#endif GLOBAL_ENTRY(ftrace_stub) mov r3 = b0 -- cgit v1.2.3