Commit 52a22e6c authored by Sven Schnelle's avatar Sven Schnelle Committed by Helge Deller
Browse files

parisc/ftrace: Add KPROBES_ON_FTRACE 



Allow KPROBES to use the ftrace infrastructure on PA-RISC.

Signed-off-by: default avatarSven Schnelle <svens@stackframe.org>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent d562aca3

Documentation/features/debug/kprobes-on-ftrace/arch-support.txt

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ 
    |       nds32: | TODO |

    |       nios2: | TODO |

    |    openrisc: | TODO |

    |      parisc: | TODO |

    |      parisc: |  ok  |

    |     powerpc: |  ok  |

    |       riscv: | TODO |

    |        s390: | TODO |

arch/parisc/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -61,6 +61,8 @@ config PARISC 
	select HAVE_KRETPROBES

	select HAVE_DYNAMIC_FTRACE if $(cc-option,-fpatchable-function-entry=1,1)

	select HAVE_FTRACE_MCOUNT_RECORD if HAVE_DYNAMIC_FTRACE

	select HAVE_KPROBES_ON_FTRACE

	select HAVE_DYNAMIC_FTRACE_WITH_REGS



	help

	  The PA-RISC microprocessor is designed by Hewlett-Packard and used

arch/parisc/kernel/entry.S

+99 −0
Original line number Diff line number Diff line
@@ -1996,6 +1996,7 @@ _mcount: 
	 * calling mcount(), and 2 instructions for ftrace_stub().  That way we

	 * have all on one L1 cacheline.

	 */

	ldi	0, %arg3

	b	ftrace_function_trampoline

	copy	%r3, %arg2	/* caller original %sp */

ftrace_stub:
@@ -2048,6 +2049,7 @@ ftrace_caller: 
	LDREG	0(%r3), %r25

	copy	%rp, %r26

	ldo	-8(%r25), %r25

	ldi	0, %r23		/* no pt_regs */

	b,l	ftrace_function_trampoline, %rp

	copy	%r3, %r24
@@ -2075,6 +2077,103 @@ ftrace_caller: 


ENDPROC_CFI(ftrace_caller)



#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS

ENTRY_CFI(ftrace_regs_caller,caller,frame=FTRACE_FRAME_SIZE+PT_SZ_ALGN,

	CALLS,SAVE_RP,SAVE_SP)

ftrace_regs_caller:

	.global ftrace_regs_caller



	ldo	-FTRACE_FRAME_SIZE(%sp), %r1

	STREG	%rp, -RP_OFFSET(%r1)



	copy	%sp, %r1

	ldo	PT_SZ_ALGN(%sp), %sp



	STREG	%rp, PT_GR2(%r1)

	STREG	%r3, PT_GR3(%r1)

	STREG	%r4, PT_GR4(%r1)

	STREG	%r5, PT_GR5(%r1)

	STREG	%r6, PT_GR6(%r1)

	STREG	%r7, PT_GR7(%r1)

	STREG	%r8, PT_GR8(%r1)

	STREG	%r9, PT_GR9(%r1)

	STREG   %r10, PT_GR10(%r1)

	STREG   %r11, PT_GR11(%r1)

	STREG   %r12, PT_GR12(%r1)

	STREG   %r13, PT_GR13(%r1)

	STREG   %r14, PT_GR14(%r1)

	STREG   %r15, PT_GR15(%r1)

	STREG   %r16, PT_GR16(%r1)

	STREG   %r17, PT_GR17(%r1)

	STREG   %r18, PT_GR18(%r1)

	STREG	%r19, PT_GR19(%r1)

	STREG	%r20, PT_GR20(%r1)

	STREG	%r21, PT_GR21(%r1)

	STREG	%r22, PT_GR22(%r1)

	STREG	%r23, PT_GR23(%r1)

	STREG	%r24, PT_GR24(%r1)

	STREG	%r25, PT_GR25(%r1)

	STREG	%r26, PT_GR26(%r1)

	STREG	%r27, PT_GR27(%r1)

	STREG	%r28, PT_GR28(%r1)

	STREG	%r29, PT_GR29(%r1)

	STREG	%r30, PT_GR30(%r1)

	STREG	%r31, PT_GR31(%r1)

	mfctl	%cr11, %r26

	STREG	%r26, PT_SAR(%r1)



	copy	%rp, %r26

	LDREG	-FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25

	ldo	-8(%r25), %r25

	copy	%r3, %arg2

	b,l	ftrace_function_trampoline, %rp

	copy	%r1, %arg3 /* struct pt_regs */



	ldo	-PT_SZ_ALGN(%sp), %r1



	LDREG	PT_SAR(%r1), %rp

	mtctl	%rp, %cr11



	LDREG	PT_GR2(%r1), %rp

	LDREG	PT_GR3(%r1), %r3

	LDREG	PT_GR4(%r1), %r4

	LDREG	PT_GR5(%r1), %r5

	LDREG	PT_GR6(%r1), %r6

	LDREG	PT_GR7(%r1), %r7

	LDREG	PT_GR8(%r1), %r8

	LDREG	PT_GR9(%r1), %r9

	LDREG   PT_GR10(%r1),%r10

	LDREG   PT_GR11(%r1),%r11

	LDREG   PT_GR12(%r1),%r12

	LDREG   PT_GR13(%r1),%r13

	LDREG   PT_GR14(%r1),%r14

	LDREG   PT_GR15(%r1),%r15

	LDREG   PT_GR16(%r1),%r16

	LDREG   PT_GR17(%r1),%r17

	LDREG   PT_GR18(%r1),%r18

	LDREG   PT_GR19(%r1),%r19

	LDREG   PT_GR20(%r1),%r20

	LDREG   PT_GR21(%r1),%r21

	LDREG   PT_GR22(%r1),%r22

	LDREG   PT_GR23(%r1),%r23

	LDREG   PT_GR24(%r1),%r24

	LDREG   PT_GR25(%r1),%r25

	LDREG   PT_GR26(%r1),%r26

	LDREG   PT_GR27(%r1),%r27

	LDREG   PT_GR28(%r1),%r28

	LDREG   PT_GR29(%r1),%r29

	LDREG   PT_GR30(%r1),%r30

	LDREG   PT_GR31(%r1),%r31



	ldo	-PT_SZ_ALGN(%sp), %sp

	LDREGM	-FTRACE_FRAME_SIZE(%sp), %r1

	/* Adjust return point to jump back to beginning of traced function */

	ldo	-4(%r1), %r1

	bv,n	(%r1)



ENDPROC_CFI(ftrace_regs_caller)



#endif

#endif



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

arch/parisc/kernel/ftrace.c

+55 −3
Original line number Diff line number Diff line
@@ -13,6 +13,8 @@ 
#include <linux/init.h>

#include <linux/ftrace.h>

#include <linux/uaccess.h>

#include <linux/kprobes.h>

#include <linux/ptrace.h>



#include <asm/assembly.h>

#include <asm/sections.h>
@@ -48,7 +50,8 @@ static void __hot prepare_ftrace_return(unsigned long *parent, 


void notrace __hot ftrace_function_trampoline(unsigned long parent,

				unsigned long self_addr,

				unsigned long org_sp_gr3)

				unsigned long org_sp_gr3,

				struct pt_regs *regs)

{

#ifndef CONFIG_DYNAMIC_FTRACE

	extern ftrace_func_t ftrace_trace_function;
@@ -58,7 +61,7 @@ void notrace __hot ftrace_function_trampoline(unsigned long parent, 
	if (function_trace_op->flags & FTRACE_OPS_FL_ENABLED &&

	    ftrace_trace_function != ftrace_stub)

		ftrace_trace_function(self_addr, parent,

				function_trace_op, NULL);

				function_trace_op, regs);



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	if (ftrace_graph_return != (trace_func_graph_ret_t) ftrace_stub ||
@@ -100,6 +103,12 @@ int ftrace_update_ftrace_func(ftrace_func_t func) 
	return 0;

}



int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,

			unsigned long addr)

{

	return 0;

}



unsigned long ftrace_call_adjust(unsigned long addr)

{

	return addr+(FTRACE_PATCHABLE_FUNCTION_SIZE-1)*4;
@@ -191,3 +200,46 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, 
	return 0;

}

#endif



#ifdef CONFIG_KPROBES_ON_FTRACE

void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,

			   struct ftrace_ops *ops, struct pt_regs *regs)

{

	struct kprobe_ctlblk *kcb;

	struct kprobe *p = get_kprobe((kprobe_opcode_t *)ip);



	if (unlikely(!p) || kprobe_disabled(p))

		return;



	if (kprobe_running()) {

		kprobes_inc_nmissed_count(p);

		return;

	}



	__this_cpu_write(current_kprobe, p);



	kcb = get_kprobe_ctlblk();

	kcb->kprobe_status = KPROBE_HIT_ACTIVE;



	regs->iaoq[0] = ip;

	regs->iaoq[1] = ip + 4;



	if (!p->pre_handler || !p->pre_handler(p, regs)) {

		regs->iaoq[0] = ip + 4;

		regs->iaoq[1] = ip + 8;



		if (unlikely(p->post_handler)) {

			kcb->kprobe_status = KPROBE_HIT_SSDONE;

			p->post_handler(p, regs, 0);

		}

	}

	__this_cpu_write(current_kprobe, NULL);

}

NOKPROBE_SYMBOL(kprobe_ftrace_handler);



int arch_prepare_kprobe_ftrace(struct kprobe *p)

{

	p->ainsn.insn = NULL;

	return 0;

}

#endif