Commit 26f45274 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

Merge branch 'tip/perf/core' of... 

Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

 into perf/core

Pull tracing updates from Steve Rostedt.

Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parents 4553f0b9 c6aaf4d0

arch/x86/kernel/entry_32.S

+1 −2
Original line number Diff line number Diff line
@@ -1148,7 +1148,6 @@ ENTRY(ftrace_regs_caller) 
	 * ip location, and move flags into the return ip location.

	 */

	pushl 4(%esp)	/* save return ip into ip slot */

	subl $MCOUNT_INSN_SIZE, (%esp)	/* Adjust ip */



	pushl $0	/* Load 0 into orig_ax */

	pushl %gs
@@ -1169,6 +1168,7 @@ ENTRY(ftrace_regs_caller) 
	movl $__KERNEL_CS,13*4(%esp)



	movl 12*4(%esp), %eax	/* Load ip (1st parameter) */

	subl $MCOUNT_INSN_SIZE, %eax	/* Adjust ip */

	movl 0x4(%ebp), %edx	/* Load parent ip (2nd parameter) */

	leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */

	pushl %esp		/* Save pt_regs as 4th parameter */
@@ -1180,7 +1180,6 @@ GLOBAL(ftrace_regs_call) 
	movl 14*4(%esp), %eax	/* Move flags back into cs */

	movl %eax, 13*4(%esp)	/* Needed to keep addl from modifying flags */

	movl 12*4(%esp), %eax	/* Get return ip from regs->ip */

	addl $MCOUNT_INSN_SIZE, %eax

	movl %eax, 14*4(%esp)	/* Put return ip back for ret */



	popl %ebx

arch/x86/kernel/entry_64.S

+4 −0
Original line number Diff line number Diff line
@@ -165,6 +165,10 @@ GLOBAL(ftrace_regs_call) 
	movq EFLAGS(%rsp), %rax

	movq %rax, SS(%rsp)



	/* Handlers can change the RIP */

	movq RIP(%rsp), %rax

	movq %rax, SS+8(%rsp)



	/* restore the rest of pt_regs */

	movq R15(%rsp), %r15

	movq R14(%rsp), %r14

arch/x86/kernel/kprobes.c

+31 −12
Original line number Diff line number Diff line
@@ -541,6 +541,8 @@ reenter_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb 
	return 1;

}



static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,

				      struct kprobe_ctlblk *kcb);

/*

 * Interrupts are disabled on entry as trap3 is an interrupt gate and they

 * remain disabled throughout this function.
@@ -599,6 +601,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) 
	} else if (kprobe_running()) {

		p = __this_cpu_read(current_kprobe);

		if (p->break_handler && p->break_handler(p, regs)) {

#ifdef KPROBES_CAN_USE_FTRACE

			if (kprobe_ftrace(p)) {

				skip_singlestep(p, regs, kcb);

				return 1;

			}

#endif

			setup_singlestep(p, regs, kcb, 0);

			return 1;

		}
@@ -1053,6 +1061,21 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) 
}



#ifdef KPROBES_CAN_USE_FTRACE

static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,

				      struct kprobe_ctlblk *kcb)

{

	/*

	 * Emulate singlestep (and also recover regs->ip)

	 * as if there is a 5byte nop

	 */

	regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;

	if (unlikely(p->post_handler)) {

		kcb->kprobe_status = KPROBE_HIT_SSDONE;

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

	}

	__this_cpu_write(current_kprobe, NULL);

}



/* Ftrace callback handler for kprobes */

void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,

				     struct ftrace_ops *ops, struct pt_regs *regs)
@@ -1072,21 +1095,17 @@ void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, 
	if (kprobe_running()) {

		kprobes_inc_nmissed_count(p);

	} else {

		regs->ip += sizeof(kprobe_opcode_t);

		/* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */

		regs->ip = ip + sizeof(kprobe_opcode_t);



		__this_cpu_write(current_kprobe, p);

		kcb->kprobe_status = KPROBE_HIT_ACTIVE;

		if (p->pre_handler)

			p->pre_handler(p, regs);



		if (unlikely(p->post_handler)) {

			/* Emulate singlestep as if there is a 5byte nop */

			regs->ip = ip + MCOUNT_INSN_SIZE;

			kcb->kprobe_status = KPROBE_HIT_SSDONE;

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

		}

		__this_cpu_write(current_kprobe, NULL);

		regs->ip = ip;	/* Recover for next callback */

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

			skip_singlestep(p, regs, kcb);

		/*

		 * If pre_handler returns !0, it sets regs->ip and

		 * resets current kprobe.

		 */

	}

end:

	local_irq_restore(flags);

kernel/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -98,7 +98,7 @@ obj-$(CONFIG_COMPAT_BINFMT_ELF) += elfcore.o 
obj-$(CONFIG_BINFMT_ELF_FDPIC) += elfcore.o

obj-$(CONFIG_FUNCTION_TRACER) += trace/

obj-$(CONFIG_TRACING) += trace/

obj-$(CONFIG_X86_DS) += trace/

obj-$(CONFIG_TRACE_CLOCK) += trace/

obj-$(CONFIG_RING_BUFFER) += trace/

obj-$(CONFIG_TRACEPOINTS) += trace/

obj-$(CONFIG_IRQ_WORK) += irq_work.o

kernel/kprobes.c

+0 −3
Original line number Diff line number Diff line
@@ -1418,9 +1418,6 @@ static __kprobes int check_kprobe_address_safe(struct kprobe *p, 
		/* Given address is not on the instruction boundary */

		if ((unsigned long)p->addr != ftrace_addr)

			return -EILSEQ;

		/* break_handler (jprobe) can not work with ftrace */

		if (p->break_handler)

			return -EINVAL;

		p->flags |= KPROBE_FLAG_FTRACE;

#else	/* !KPROBES_CAN_USE_FTRACE */

		return -EINVAL;