Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 46542888 authored by Steven Rostedt's avatar Steven Rostedt Committed by Benjamin Herrenschmidt
Browse files

powerpc64, tracing: add function graph tracer with dynamic tracing 



This is the port of the function graph tracer to PowerPC with
dynamic tracing.

Geoff Lavand tested on PS3.

Tested-by: default avatarGeoff Levand <geoffrey.levand@am.sony.com>
Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 6794c782

arch/powerpc/Kconfig

+1 −1
Original line number Original line Diff line number Diff line
@@ -111,7 +111,7 @@ config PPC 
	select HAVE_FTRACE_MCOUNT_RECORD

	select HAVE_FTRACE_MCOUNT_RECORD

	select HAVE_DYNAMIC_FTRACE

	select HAVE_DYNAMIC_FTRACE

	select HAVE_FUNCTION_TRACER

	select HAVE_FUNCTION_TRACER

	select HAVE_FUNCTION_GRAPH_TRACER if !DYNAMIC_FTRACE && PPC64

	select HAVE_FUNCTION_GRAPH_TRACER if PPC64

	select ARCH_WANT_OPTIONAL_GPIOLIB

	select ARCH_WANT_OPTIONAL_GPIOLIB

	select HAVE_IDE

	select HAVE_IDE

	select HAVE_IOREMAP_PROT

	select HAVE_IOREMAP_PROT

arch/powerpc/kernel/entry_64.S

+7 −1
Original line number Original line Diff line number Diff line
@@ -908,6 +908,12 @@ _GLOBAL(ftrace_caller) 
ftrace_call:

ftrace_call:

	bl	ftrace_stub

	bl	ftrace_stub

	nop

	nop

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

.globl ftrace_graph_call

ftrace_graph_call:

	b	ftrace_graph_stub

_GLOBAL(ftrace_graph_stub)

#endif

	ld	r0, 128(r1)

	ld	r0, 128(r1)

	mtlr	r0

	mtlr	r0

	addi	r1, r1, 112

	addi	r1, r1, 112
@@ -946,7 +952,7 @@ _GLOBAL(ftrace_stub) 
#endif /* CONFIG_DYNAMIC_FTRACE */

#endif /* CONFIG_DYNAMIC_FTRACE */





#ifdef CONFIG_FUNCTION_GRAPH_TRACER

#ifdef CONFIG_FUNCTION_GRAPH_TRACER

ftrace_graph_caller:

_GLOBAL(ftrace_graph_caller)

	/* load r4 with local address */

	/* load r4 with local address */

	ld	r4, 128(r1)

	ld	r4, 128(r1)

	subi	r4, r4, MCOUNT_INSN_SIZE

	subi	r4, r4, MCOUNT_INSN_SIZE

arch/powerpc/kernel/ftrace.c

+41 −6
Original line number Original line Diff line number Diff line
@@ -43,7 +43,8 @@ static unsigned char *ftrace_nop_replace(void) 
	return (char *)&ftrace_nop;

	return (char *)&ftrace_nop;

}

}





static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)

static unsigned char *

ftrace_call_replace(unsigned long ip, unsigned long addr, int link)

{

{

	static unsigned int op;

	static unsigned int op;
@@ -55,8 +56,9 @@ static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) 
	 */

	 */

	addr = GET_ADDR(addr);

	addr = GET_ADDR(addr);





	/* Set to "bl addr" */

	/* if (link) set op to 'bl' else 'b' */

	op = 0x48000001 | (ftrace_calc_offset(ip, addr) & 0x03fffffc);

	op = 0x48000000 | (link ? 1 : 0);

	op |= (ftrace_calc_offset(ip, addr) & 0x03fffffc);





	/*

	/*

	 * No locking needed, this must be called via kstop_machine

	 * No locking needed, this must be called via kstop_machine
@@ -344,7 +346,7 @@ int ftrace_make_nop(struct module *mod, 
	 */

	 */

	if (test_24bit_addr(ip, addr)) {

	if (test_24bit_addr(ip, addr)) {

		/* within range */

		/* within range */

		old = ftrace_call_replace(ip, addr);

		old = ftrace_call_replace(ip, addr, 1);

		new = ftrace_nop_replace();

		new = ftrace_nop_replace();

		return ftrace_modify_code(ip, old, new);

		return ftrace_modify_code(ip, old, new);

	}

	}
@@ -484,7 +486,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
	if (test_24bit_addr(ip, addr)) {

	if (test_24bit_addr(ip, addr)) {

		/* within range */

		/* within range */

		old = ftrace_nop_replace();

		old = ftrace_nop_replace();

		new = ftrace_call_replace(ip, addr);

		new = ftrace_call_replace(ip, addr, 1);

		return ftrace_modify_code(ip, old, new);

		return ftrace_modify_code(ip, old, new);

	}

	}
@@ -513,7 +515,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) 
	int ret;

	int ret;





	memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);

	memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);

	new = ftrace_call_replace(ip, (unsigned long)func);

	new = ftrace_call_replace(ip, (unsigned long)func, 1);

	ret = ftrace_modify_code(ip, old, new);

	ret = ftrace_modify_code(ip, old, new);





	return ret;

	return ret;
@@ -532,6 +534,39 @@ int __init ftrace_dyn_arch_init(void *data) 




#ifdef CONFIG_FUNCTION_GRAPH_TRACER

#ifdef CONFIG_FUNCTION_GRAPH_TRACER





#ifdef CONFIG_DYNAMIC_FTRACE

extern void ftrace_graph_call(void);

extern void ftrace_graph_stub(void);



int ftrace_enable_ftrace_graph_caller(void)

{

	unsigned long ip = (unsigned long)(&ftrace_graph_call);

	unsigned long addr = (unsigned long)(&ftrace_graph_caller);

	unsigned long stub = (unsigned long)(&ftrace_graph_stub);

	unsigned char old[MCOUNT_INSN_SIZE], *new;



	new = ftrace_call_replace(ip, stub, 0);

	memcpy(old, new, MCOUNT_INSN_SIZE);

	new = ftrace_call_replace(ip, addr, 0);



	return ftrace_modify_code(ip, old, new);

}



int ftrace_disable_ftrace_graph_caller(void)

{

	unsigned long ip = (unsigned long)(&ftrace_graph_call);

	unsigned long addr = (unsigned long)(&ftrace_graph_caller);

	unsigned long stub = (unsigned long)(&ftrace_graph_stub);

	unsigned char old[MCOUNT_INSN_SIZE], *new;



	new = ftrace_call_replace(ip, addr, 0);

	memcpy(old, new, MCOUNT_INSN_SIZE);

	new = ftrace_call_replace(ip, stub, 0);



	return ftrace_modify_code(ip, old, new);

}

#endif /* CONFIG_DYNAMIC_FTRACE */



/*

/*

 * Hook the return address and push it in the stack of return addrs

 * Hook the return address and push it in the stack of return addrs

 * in current thread info.

 * in current thread info.