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authorMike Frysinger <vapier@gentoo.org>2009-06-09 07:25:09 -0400
committerMike Frysinger <vapier@gentoo.org>2009-06-13 07:20:15 -0400
commit1c873be744410e26fb91ee9228c90adff6eabe15 (patch)
treeee326bbd1399e4562e4584b3c1b800c2cfdea285 /arch
parent6fa68e7a7f0641e8b7f263141d600877cdc2b5f2 (diff)
Blackfin: initial support for ftrace
Just the basic ftrace support here -- mcount and the ftrace stub. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/blackfin/Kconfig1
-rw-r--r--arch/blackfin/include/asm/ftrace.h14
-rw-r--r--arch/blackfin/kernel/Makefile1
-rw-r--r--arch/blackfin/kernel/bfin_ksyms.c5
-rw-r--r--arch/blackfin/kernel/ftrace-entry.S72
5 files changed, 92 insertions, 1 deletions
diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index d03fd638e9aa..ea8d92c1d447 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -19,6 +19,7 @@ config RWSEM_XCHGADD_ALGORITHM
19 19
20config BLACKFIN 20config BLACKFIN
21 def_bool y 21 def_bool y
22 select HAVE_FUNCTION_TRACER
22 select HAVE_IDE 23 select HAVE_IDE
23 select HAVE_KERNEL_GZIP 24 select HAVE_KERNEL_GZIP
24 select HAVE_KERNEL_BZIP2 25 select HAVE_KERNEL_BZIP2
diff --git a/arch/blackfin/include/asm/ftrace.h b/arch/blackfin/include/asm/ftrace.h
index 40a8c178f10d..8643680f0f78 100644
--- a/arch/blackfin/include/asm/ftrace.h
+++ b/arch/blackfin/include/asm/ftrace.h
@@ -1 +1,13 @@
1/* empty */ 1/*
2 * Blackfin ftrace code
3 *
4 * Copyright 2009 Analog Devices Inc.
5 * Licensed under the GPL-2 or later.
6 */
7
8#ifndef __ASM_BFIN_FTRACE_H__
9#define __ASM_BFIN_FTRACE_H__
10
11#define MCOUNT_INSN_SIZE 8 /* sizeof mcount call: LINK + CALL */
12
13#endif
diff --git a/arch/blackfin/kernel/Makefile b/arch/blackfin/kernel/Makefile
index a66dda4f4b1f..d2ae285e5b6e 100644
--- a/arch/blackfin/kernel/Makefile
+++ b/arch/blackfin/kernel/Makefile
@@ -15,6 +15,7 @@ else
15 obj-y += time.o 15 obj-y += time.o
16endif 16endif
17 17
18obj-$(CONFIG_FUNCTION_TRACER) += ftrace-entry.o
18obj-$(CONFIG_IPIPE) += ipipe.o 19obj-$(CONFIG_IPIPE) += ipipe.o
19obj-$(CONFIG_IPIPE_TRACE_MCOUNT) += mcount.o 20obj-$(CONFIG_IPIPE_TRACE_MCOUNT) += mcount.o
20obj-$(CONFIG_BFIN_GPTIMERS) += gptimers.o 21obj-$(CONFIG_BFIN_GPTIMERS) += gptimers.o
diff --git a/arch/blackfin/kernel/bfin_ksyms.c b/arch/blackfin/kernel/bfin_ksyms.c
index 53e893ff708a..aa05e638fb7c 100644
--- a/arch/blackfin/kernel/bfin_ksyms.c
+++ b/arch/blackfin/kernel/bfin_ksyms.c
@@ -103,3 +103,8 @@ EXPORT_SYMBOL(__raw_smp_mark_barrier_asm);
103EXPORT_SYMBOL(__raw_smp_check_barrier_asm); 103EXPORT_SYMBOL(__raw_smp_check_barrier_asm);
104#endif 104#endif
105#endif 105#endif
106
107#ifdef CONFIG_FUNCTION_TRACER
108extern void _mcount(void);
109EXPORT_SYMBOL(_mcount);
110#endif
diff --git a/arch/blackfin/kernel/ftrace-entry.S b/arch/blackfin/kernel/ftrace-entry.S
new file mode 100644
index 000000000000..ce71487b515f
--- /dev/null
+++ b/arch/blackfin/kernel/ftrace-entry.S
@@ -0,0 +1,72 @@
1/*
2 * mcount and friends -- ftrace stuff
3 *
4 * Copyright (C) 2009 Analog Devices Inc.
5 * Licensed under the GPL-2 or later.
6 */
7
8#include <linux/linkage.h>
9#include <asm/ftrace.h>
10
11.text
12
13/* GCC will have called us before setting up the function prologue, so we
14 * can clobber the normal scratch registers, but we need to make sure to
15 * save/restore the registers used for argument passing (R0-R2) in case
16 * the profiled function is using them. With data registers, R3 is the
17 * only one we can blow away. With pointer registers, we have P0-P2.
18 *
19 * Upon entry, the RETS will point to the top of the current profiled
20 * function. And since GCC setup the frame for us, the previous function
21 * will be waiting there. mmmm pie.
22 */
23ENTRY(__mcount)
24 /* save third function arg early so we can do testing below */
25 [--sp] = r2;
26
27 /* load the function pointer to the tracer */
28 p0.l = _ftrace_trace_function;
29 p0.h = _ftrace_trace_function;
30 r3 = [p0];
31
32 /* optional micro optimization: don't call the stub tracer */
33 r2.l = _ftrace_stub;
34 r2.h = _ftrace_stub;
35 cc = r2 == r3;
36 if ! cc jump .Ldo_trace;
37
38 r2 = [sp++];
39 rts;
40
41.Ldo_trace:
42
43 /* save first/second function arg and the return register */
44 [--sp] = r0;
45 [--sp] = r1;
46 [--sp] = rets;
47
48 /* setup the tracer function */
49 p0 = r3;
50
51 /* tracer(ulong frompc, ulong selfpc):
52 * frompc: the pc that did the call to ...
53 * selfpc: ... this location
54 * the selfpc itself will need adjusting for the mcount call
55 */
56 r1 = rets;
57 r0 = [fp + 4];
58 r1 += -MCOUNT_INSN_SIZE;
59
60 /* call the tracer */
61 call (p0);
62
63 /* restore state and get out of dodge */
64 rets = [sp++];
65 r1 = [sp++];
66 r0 = [sp++];
67 r2 = [sp++];
68
69.globl _ftrace_stub
70_ftrace_stub:
71 rts;
72ENDPROC(__mcount)