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linux-pinenote/arch/microblaze/kernel/mcount.S

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microblaze: ftrace: add static function tracer If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to _mcount will be inserted into each kernel function. so, there is a possibility to trace the kernel functions in _mcount. This patch add the specific _mcount support for static function tracing. by default, ftrace_trace_function is initialized as ftrace_stub(an empty function), so, the default _mcount will introduce very little overhead. after enabling ftrace in user-space, it will jump to a real tracing function and do static function tracing for us. Commit message from Wu Zhangjin <wuzhangjin@gmail.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 09:40:14 +01:00
/*
* Low-level ftrace handling
*
* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2009 PetaLogix
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*/
#include <linux/linkage.h>
#define NOALIGN_ENTRY(name) .globl name; name:
/* FIXME MS: I think that I don't need to save all regs */
#define SAVE_REGS \
addik r1, r1, -120; \
swi r2, r1, 4; \
swi r3, r1, 8; \
swi r4, r1, 12; \
swi r5, r1, 116; \
swi r6, r1, 16; \
swi r7, r1, 20; \
swi r8, r1, 24; \
swi r9, r1, 28; \
swi r10, r1, 32; \
swi r11, r1, 36; \
swi r12, r1, 40; \
swi r13, r1, 44; \
swi r14, r1, 48; \
swi r16, r1, 52; \
swi r17, r1, 56; \
swi r18, r1, 60; \
swi r19, r1, 64; \
swi r20, r1, 68; \
swi r21, r1, 72; \
swi r22, r1, 76; \
swi r23, r1, 80; \
swi r24, r1, 84; \
swi r25, r1, 88; \
swi r26, r1, 92; \
swi r27, r1, 96; \
swi r28, r1, 100; \
swi r29, r1, 104; \
swi r30, r1, 108; \
swi r31, r1, 112;
#define RESTORE_REGS \
lwi r2, r1, 4; \
lwi r3, r1, 8; \
lwi r4, r1, 12; \
lwi r5, r1, 116; \
lwi r6, r1, 16; \
lwi r7, r1, 20; \
lwi r8, r1, 24; \
lwi r9, r1, 28; \
lwi r10, r1, 32; \
lwi r11, r1, 36; \
lwi r12, r1, 40; \
lwi r13, r1, 44; \
lwi r14, r1, 48; \
lwi r16, r1, 52; \
lwi r17, r1, 56; \
lwi r18, r1, 60; \
lwi r19, r1, 64; \
lwi r20, r1, 68; \
lwi r21, r1, 72; \
lwi r22, r1, 76; \
lwi r23, r1, 80; \
lwi r24, r1, 84; \
lwi r25, r1, 88; \
lwi r26, r1, 92; \
lwi r27, r1, 96; \
lwi r28, r1, 100; \
lwi r29, r1, 104; \
lwi r30, r1, 108; \
lwi r31, r1, 112; \
addik r1, r1, 120;
ENTRY(ftrace_stub)
rtsd r15, 8;
nop;
ENTRY(_mcount)
microblaze: ftrace: Add dynamic trace support With dynamic function tracer, by default, _mcount is defined as an "empty" function, it returns directly without any more action. When enabling it in user-space, it will jump to a real tracing function(ftrace_caller), and do the real job for us. Differ from the static function tracer, dynamic function tracer provides two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the tracing of some indicated kernel functions(set_ftrace_filter). In the kernel version, there is only one "_mcount" string for every kernel function, so, we just need to match this one in mcount_regex of scripts/recordmcount.pl. For more information please look at code and Documentation/trace folder. Steven ACK that scripts/recordmcount.pl part. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-12-10 14:15:44 +01:00
#ifdef CONFIG_DYNAMIC_FTRACE
ENTRY(ftrace_caller)
/* MS: It is just barrier which is removed from C code */
rtsd r15, 8
nop
#endif /* CONFIG_DYNAMIC_FTRACE */
microblaze: ftrace: add static function tracer If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to _mcount will be inserted into each kernel function. so, there is a possibility to trace the kernel functions in _mcount. This patch add the specific _mcount support for static function tracing. by default, ftrace_trace_function is initialized as ftrace_stub(an empty function), so, the default _mcount will introduce very little overhead. after enabling ftrace in user-space, it will jump to a real tracing function and do static function tracing for us. Commit message from Wu Zhangjin <wuzhangjin@gmail.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 09:40:14 +01:00
SAVE_REGS
swi r15, r1, 0;
microblaze: ftrace: add function graph support For more information look at Documentation/trace folder. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:32:10 +01:00
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
microblaze: ftrace: Add dynamic function graph tracer This patch add support for dynamic function graph tracer. There is one my expactation that I can do flush_icache after all code modification. On microblaze is this safer than do flush for every entry. For icache is used name flush but correct should be invalidation - this will be fix in upcomming new cache implementaion and WB support. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:34:15 +01:00
#ifndef CONFIG_DYNAMIC_FTRACE
microblaze: ftrace: add function graph support For more information look at Documentation/trace folder. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:32:10 +01:00
lwi r5, r0, ftrace_graph_return;
addik r6, r0, ftrace_stub; /* asm implementation */
cmpu r5, r5, r6; /* ftrace_graph_return != ftrace_stub */
beqid r5, end_graph_tracer;
nop;
lwi r6, r0, ftrace_graph_entry;
addik r5, r0, ftrace_graph_entry_stub; /* implemented in C */
cmpu r5, r5, r6; /* ftrace_graph_entry != ftrace_graph_entry_stub */
beqid r5, end_graph_tracer;
nop;
microblaze: ftrace: Add dynamic function graph tracer This patch add support for dynamic function graph tracer. There is one my expactation that I can do flush_icache after all code modification. On microblaze is this safer than do flush for every entry. For icache is used name flush but correct should be invalidation - this will be fix in upcomming new cache implementaion and WB support. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:34:15 +01:00
#else /* CONFIG_DYNAMIC_FTRACE */
NOALIGN_ENTRY(ftrace_call_graph)
/* MS: jump over graph function - replaced from C code */
bri end_graph_tracer
#endif /* CONFIG_DYNAMIC_FTRACE */
microblaze: ftrace: add function graph support For more information look at Documentation/trace folder. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:32:10 +01:00
addik r5, r1, 120; /* MS: load parent addr */
addik r6, r15, 0; /* MS: load current function addr */
bralid r15, prepare_ftrace_return;
nop;
/* MS: graph was taken that's why - can jump over function trace */
brid end;
nop;
end_graph_tracer:
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
microblaze: ftrace: Add dynamic trace support With dynamic function tracer, by default, _mcount is defined as an "empty" function, it returns directly without any more action. When enabling it in user-space, it will jump to a real tracing function(ftrace_caller), and do the real job for us. Differ from the static function tracer, dynamic function tracer provides two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the tracing of some indicated kernel functions(set_ftrace_filter). In the kernel version, there is only one "_mcount" string for every kernel function, so, we just need to match this one in mcount_regex of scripts/recordmcount.pl. For more information please look at code and Documentation/trace folder. Steven ACK that scripts/recordmcount.pl part. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-12-10 14:15:44 +01:00
#ifndef CONFIG_DYNAMIC_FTRACE
microblaze: ftrace: add static function tracer If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to _mcount will be inserted into each kernel function. so, there is a possibility to trace the kernel functions in _mcount. This patch add the specific _mcount support for static function tracing. by default, ftrace_trace_function is initialized as ftrace_stub(an empty function), so, the default _mcount will introduce very little overhead. after enabling ftrace in user-space, it will jump to a real tracing function and do static function tracing for us. Commit message from Wu Zhangjin <wuzhangjin@gmail.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 09:40:14 +01:00
/* MS: test function trace if is taken or not */
lwi r20, r0, ftrace_trace_function;
addik r6, r0, ftrace_stub;
cmpu r5, r20, r6; /* ftrace_trace_function != ftrace_stub */
beqid r5, end; /* MS: not taken -> jump over */
nop;
microblaze: ftrace: Add dynamic trace support With dynamic function tracer, by default, _mcount is defined as an "empty" function, it returns directly without any more action. When enabling it in user-space, it will jump to a real tracing function(ftrace_caller), and do the real job for us. Differ from the static function tracer, dynamic function tracer provides two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the tracing of some indicated kernel functions(set_ftrace_filter). In the kernel version, there is only one "_mcount" string for every kernel function, so, we just need to match this one in mcount_regex of scripts/recordmcount.pl. For more information please look at code and Documentation/trace folder. Steven ACK that scripts/recordmcount.pl part. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-12-10 14:15:44 +01:00
#else /* CONFIG_DYNAMIC_FTRACE */
NOALIGN_ENTRY(ftrace_call)
/* instruction for setup imm FUNC_part1, addik r20, r0, FUNC_part2 */
nop
nop
#endif /* CONFIG_DYNAMIC_FTRACE */
microblaze: ftrace: add static function tracer If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to _mcount will be inserted into each kernel function. so, there is a possibility to trace the kernel functions in _mcount. This patch add the specific _mcount support for static function tracing. by default, ftrace_trace_function is initialized as ftrace_stub(an empty function), so, the default _mcount will introduce very little overhead. after enabling ftrace in user-space, it will jump to a real tracing function and do static function tracing for us. Commit message from Wu Zhangjin <wuzhangjin@gmail.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 09:40:14 +01:00
/* static normal trace */
lwi r6, r1, 120; /* MS: load parent addr */
microblaze: ftrace: Pass the first calling instruction for dynamic ftrace Selftest for dynamic ftrace requres to pass address of the first calling instruction because hash function is calculated from it. ftrace_update_ftrace_func setups pointer to function which is called in _mcount function. trace_selftest is not aware about instruction size (for microblaze 8 - imm and addik) and that's why we have to pass in r5 address of imm not addik which is in r15.12 For more info look at ftrace_ops_list_func/ftrace.c. Signed-off-by: Michal Simek <monstr@monstr.eu>
2012-05-07 14:21:02 +02:00
addik r5, r15, -4; /* MS: load current function addr */
microblaze: ftrace: add static function tracer If -pg of gcc is enabled with CONFIG_FUNCTION_TRACER=y. a calling to _mcount will be inserted into each kernel function. so, there is a possibility to trace the kernel functions in _mcount. This patch add the specific _mcount support for static function tracing. by default, ftrace_trace_function is initialized as ftrace_stub(an empty function), so, the default _mcount will introduce very little overhead. after enabling ftrace in user-space, it will jump to a real tracing function and do static function tracing for us. Commit message from Wu Zhangjin <wuzhangjin@gmail.com> Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 09:40:14 +01:00
/* MS: here is dependency on previous code */
brald r15, r20; /* MS: jump to ftrace handler */
nop;
end:
lwi r15, r1, 0;
RESTORE_REGS
rtsd r15, 8; /* MS: jump back */
nop;
microblaze: ftrace: add function graph support For more information look at Documentation/trace folder. Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-11-16 10:32:10 +01:00
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
ENTRY(return_to_handler)
nop; /* MS: just barrier for rtsd r15, 8 */
nop;
SAVE_REGS
swi r15, r1, 0;
/* MS: find out returning address */
bralid r15, ftrace_return_to_handler;
nop;
/* MS: return value from ftrace_return_to_handler is my returning addr
* must be before restore regs because I have to restore r3 content */
addik r15, r3, 0;
RESTORE_REGS
rtsd r15, 8; /* MS: jump back */
nop;
#endif /* CONFIG_FUNCTION_TRACER */
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