ftrace: extend sysprof plugin some more (56a08bdc) · Commits · e / devices / android_kernel_xiaomi_sm6125

kernel/trace/trace_sysprof.c

+76 −4

Original line number	Diff line number	Diff line
		@@ -3,7 +3,7 @@
		*
		* Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
		* Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
		*
		* Copyright (C) 2004, 2005, Soeren Sandmann
		*/
		#include <linux/kallsyms.h>
		#include <linux/debugfs.h>
		@@ -11,13 +11,17 @@
		#include <linux/uaccess.h>
		#include <linux/ftrace.h>
		#include <linux/module.h>
		#include <linux/irq.h>
		#include <linux/fs.h>

		#include "trace.h"

		static struct trace_array *ctx_trace;
		static struct trace_array *sysprof_trace;
		static int __read_mostly tracer_enabled;

		/*
		* 10 msecs for now:
		*/
		static const unsigned long sample_period = 1000000;

		/*
		@@ -25,10 +29,78 @@ static const unsigned long sample_period = 1000000;
		*/
		static DEFINE_PER_CPU(struct hrtimer, stack_trace_hrtimer);

		struct stack_frame {
		const void __user *next_fp;
		unsigned long return_address;
		};

		static int copy_stack_frame(const void __user fp, struct stack_frame frame)
		{
		if (!access_ok(VERIFY_READ, fp, sizeof(*frame)))
		return 0;

		if (__copy_from_user_inatomic(frame, frame_pointer, sizeof(*frame)))
		return 0;

		return 1;
		}

		#define SYSPROF_MAX_ADDRESSES 512

		static void timer_notify(struct pt_regs *regs, int cpu)
		{
		const void __user *frame_pointer;
		struct trace_array_cpu *data;
		struct stack_frame frame;
		struct trace_array *tr;
		int is_user;
		int i;

		if (!regs)
		return;

		tr = sysprof_trace;
		data = tr->data[cpu];
		is_user = user_mode(regs);

		if (!current \|\| current->pid == 0)
		return;

		if (is_user && current->state != TASK_RUNNING)
		return;

		if (!is_user) {
		/* kernel */
		ftrace(tr, data, current->pid, 1, 0);
		return;

		}

		trace_special(tr, data, 0, current->pid, regs->ip);

		frame_pointer = (void __user *)regs->bp;

		for (i = 0; i < SYSPROF_MAX_ADDRESSES; i++) {
		if (!copy_stack_frame(frame_pointer, &frame))
		break;
		if ((unsigned long)frame_pointer < regs->sp)
		break;

		trace_special(tr, data, 1, frame.return_address,
		(unsigned long)frame_pointer);
		frame_pointer = frame.next_fp;
		}

		trace_special(tr, data, 2, current->pid, i);

		if (i == SYSPROF_MAX_ADDRESSES)
		trace_special(tr, data, -1, -1, -1);
		}

		static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer)
		{
		/* trace here */
		panic_timeout++;
		timer_notify(get_irq_regs(), smp_processor_id());

		hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));

		@@ -100,7 +172,7 @@ static notrace void stop_stack_trace(struct trace_array *tr)

		static notrace void stack_trace_init(struct trace_array *tr)
		{
		ctx_trace = tr;
		sysprof_trace = tr;

		if (tr->ctrl)
		start_stack_trace(tr);