Commit 7413af1f authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
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ftrace: Make get_ftrace_addr() and get_ftrace_addr_old() global 



Move and rename get_ftrace_addr() and get_ftrace_addr_old() to
ftrace_get_addr_new() and ftrace_get_addr_curr() respectively.

This moves these two helper functions in the generic code out from
the arch specific code, and renames them to have a better generic
name. This will allow other archs to use them as well as makes it
a bit easier to work on getting separate trampolines for different
functions.

ftrace_get_addr_new() returns the trampoline address that the mcount
call address will be converted to.

ftrace_get_addr_curr() returns the trampoline address of what the
mcount call address currently jumps to.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 94792ea0

arch/x86/kernel/ftrace.c

+5 −31
Original line number Diff line number Diff line
@@ -349,38 +349,12 @@ static int add_brk_on_nop(struct dyn_ftrace *rec) 
	return add_break(rec->ip, old);

}



/*

 * If the record has the FTRACE_FL_REGS set, that means that it

 * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS

 * is not not set, then it wants to convert to the normal callback.

 */

static unsigned long get_ftrace_addr(struct dyn_ftrace *rec)

{

	if (rec->flags & FTRACE_FL_REGS)

		return (unsigned long)FTRACE_REGS_ADDR;

	else

		return (unsigned long)FTRACE_ADDR;

}



/*

 * The FTRACE_FL_REGS_EN is set when the record already points to

 * a function that saves all the regs. Basically the '_EN' version

 * represents the current state of the function.

 */

static unsigned long get_ftrace_old_addr(struct dyn_ftrace *rec)

{

	if (rec->flags & FTRACE_FL_REGS_EN)

		return (unsigned long)FTRACE_REGS_ADDR;

	else

		return (unsigned long)FTRACE_ADDR;

}



static int add_breakpoints(struct dyn_ftrace *rec, int enable)

{

	unsigned long ftrace_addr;

	int ret;



	ftrace_addr = get_ftrace_old_addr(rec);

	ftrace_addr = ftrace_get_addr_curr(rec);



	ret = ftrace_test_record(rec, enable);
@@ -438,14 +412,14 @@ static int remove_breakpoint(struct dyn_ftrace *rec) 
		 * If not, don't touch the breakpoint, we make just create

		 * a disaster.

		 */

		ftrace_addr = get_ftrace_addr(rec);

		ftrace_addr = ftrace_get_addr_new(rec);

		nop = ftrace_call_replace(ip, ftrace_addr);



		if (memcmp(&ins[1], &nop[1], MCOUNT_INSN_SIZE - 1) == 0)

			goto update;



		/* Check both ftrace_addr and ftrace_old_addr */

		ftrace_addr = get_ftrace_old_addr(rec);

		ftrace_addr = ftrace_get_addr_curr(rec);

		nop = ftrace_call_replace(ip, ftrace_addr);



		if (memcmp(&ins[1], &nop[1], MCOUNT_INSN_SIZE - 1) != 0)
@@ -489,7 +463,7 @@ static int add_update(struct dyn_ftrace *rec, int enable) 


	ret = ftrace_test_record(rec, enable);



	ftrace_addr  = get_ftrace_addr(rec);

	ftrace_addr  = ftrace_get_addr_new(rec);



	switch (ret) {

	case FTRACE_UPDATE_IGNORE:
@@ -536,7 +510,7 @@ static int finish_update(struct dyn_ftrace *rec, int enable) 


	ret = ftrace_update_record(rec, enable);



	ftrace_addr = get_ftrace_addr(rec);

	ftrace_addr = ftrace_get_addr_new(rec);



	switch (ret) {

	case FTRACE_UPDATE_IGNORE:

include/linux/ftrace.h

+2 −0
Original line number Diff line number Diff line
@@ -400,6 +400,8 @@ int ftrace_update_record(struct dyn_ftrace *rec, int enable); 
int ftrace_test_record(struct dyn_ftrace *rec, int enable);

void ftrace_run_stop_machine(int command);

unsigned long ftrace_location(unsigned long ip);

unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec);

unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec);



extern ftrace_func_t ftrace_trace_function;

kernel/trace/ftrace.c

+36 −0
Original line number Diff line number Diff line
@@ -1755,6 +1755,42 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable) 
	return ftrace_check_record(rec, enable, 0);

}



/**

 * ftrace_get_addr_new - Get the call address to set to

 * @rec:  The ftrace record descriptor

 *

 * If the record has the FTRACE_FL_REGS set, that means that it

 * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS

 * is not not set, then it wants to convert to the normal callback.

 *

 * Returns the address of the trampoline to set to

 */

unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)

{

	if (rec->flags & FTRACE_FL_REGS)

		return (unsigned long)FTRACE_REGS_ADDR;

	else

		return (unsigned long)FTRACE_ADDR;

}



/**

 * ftrace_get_addr_curr - Get the call address that is already there

 * @rec:  The ftrace record descriptor

 *

 * The FTRACE_FL_REGS_EN is set when the record already points to

 * a function that saves all the regs. Basically the '_EN' version

 * represents the current state of the function.

 *

 * Returns the address of the trampoline that is currently being called

 */

unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)

{

	if (rec->flags & FTRACE_FL_REGS_EN)

		return (unsigned long)FTRACE_REGS_ADDR;

	else

		return (unsigned long)FTRACE_ADDR;

}



static int

__ftrace_replace_code(struct dyn_ftrace *rec, int enable)

{

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