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@@ -1,330 +0,0 @@
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-/*
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- * trace stack traces
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- *
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- * Copyright (C) 2004-2008, Soeren Sandmann
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- * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
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- * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
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- */
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-#include <linux/kallsyms.h>
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-#include <linux/debugfs.h>
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-#include <linux/hrtimer.h>
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-#include <linux/uaccess.h>
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-#include <linux/ftrace.h>
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-#include <linux/module.h>
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-#include <linux/irq.h>
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-#include <linux/fs.h>
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-
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-#include <asm/stacktrace.h>
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-
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-#include "trace.h"
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-
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-static struct trace_array *sysprof_trace;
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-static int __read_mostly tracer_enabled;
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-
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-/*
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- * 1 msec sample interval by default:
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- */
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-static unsigned long sample_period = 1000000;
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-static const unsigned int sample_max_depth = 512;
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-
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-static DEFINE_MUTEX(sample_timer_lock);
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-/*
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- * Per CPU hrtimers that do the profiling:
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- */
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-static DEFINE_PER_CPU(struct hrtimer, stack_trace_hrtimer);
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-
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-struct stack_frame_user {
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- const void __user *next_fp;
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- unsigned long return_address;
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-};
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-
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-static int
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-copy_stack_frame(const void __user *fp, struct stack_frame_user *frame)
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-{
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- int ret;
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-
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- if (!access_ok(VERIFY_READ, fp, sizeof(*frame)))
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- return 0;
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-
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- ret = 1;
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- pagefault_disable();
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- if (__copy_from_user_inatomic(frame, fp, sizeof(*frame)))
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- ret = 0;
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- pagefault_enable();
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-
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- return ret;
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-}
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-
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-struct backtrace_info {
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- struct trace_array_cpu *data;
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- struct trace_array *tr;
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- int pos;
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-};
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-
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-static void
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-backtrace_warning_symbol(void *data, char *msg, unsigned long symbol)
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-{
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- /* Ignore warnings */
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-}
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-
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-static void backtrace_warning(void *data, char *msg)
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-{
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- /* Ignore warnings */
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-}
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-
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-static int backtrace_stack(void *data, char *name)
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-{
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- /* Don't bother with IRQ stacks for now */
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- return -1;
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-}
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-
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-static void backtrace_address(void *data, unsigned long addr, int reliable)
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-{
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- struct backtrace_info *info = data;
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-
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- if (info->pos < sample_max_depth && reliable) {
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- __trace_special(info->tr, info->data, 1, addr, 0);
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-
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- info->pos++;
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- }
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-}
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-
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-static const struct stacktrace_ops backtrace_ops = {
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- .warning = backtrace_warning,
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- .warning_symbol = backtrace_warning_symbol,
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- .stack = backtrace_stack,
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- .address = backtrace_address,
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- .walk_stack = print_context_stack,
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-};
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-
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-static int
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-trace_kernel(struct pt_regs *regs, struct trace_array *tr,
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- struct trace_array_cpu *data)
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-{
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- struct backtrace_info info;
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- unsigned long bp;
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- char *stack;
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-
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- info.tr = tr;
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- info.data = data;
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- info.pos = 1;
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-
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- __trace_special(info.tr, info.data, 1, regs->ip, 0);
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-
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- stack = ((char *)regs + sizeof(struct pt_regs));
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-#ifdef CONFIG_FRAME_POINTER
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- bp = regs->bp;
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-#else
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- bp = 0;
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-#endif
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-
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- dump_trace(NULL, regs, (void *)stack, bp, &backtrace_ops, &info);
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-
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- return info.pos;
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-}
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-
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-static void timer_notify(struct pt_regs *regs, int cpu)
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-{
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- struct trace_array_cpu *data;
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- struct stack_frame_user frame;
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- struct trace_array *tr;
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- const void __user *fp;
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- int is_user;
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- int i;
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-
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- if (!regs)
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- return;
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-
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- tr = sysprof_trace;
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- data = tr->data[cpu];
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- is_user = user_mode(regs);
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-
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- if (!current || current->pid == 0)
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- return;
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-
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- if (is_user && current->state != TASK_RUNNING)
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- return;
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-
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- __trace_special(tr, data, 0, 0, current->pid);
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-
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- if (!is_user)
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- i = trace_kernel(regs, tr, data);
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- else
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- i = 0;
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-
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- /*
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- * Trace user stack if we are not a kernel thread
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- */
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- if (current->mm && i < sample_max_depth) {
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- regs = (struct pt_regs *)current->thread.sp0 - 1;
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-
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- fp = (void __user *)regs->bp;
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-
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- __trace_special(tr, data, 2, regs->ip, 0);
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-
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- while (i < sample_max_depth) {
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- frame.next_fp = NULL;
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- frame.return_address = 0;
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- if (!copy_stack_frame(fp, &frame))
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- break;
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- if ((unsigned long)fp < regs->sp)
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- break;
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-
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- __trace_special(tr, data, 2, frame.return_address,
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- (unsigned long)fp);
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- fp = frame.next_fp;
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-
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- i++;
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- }
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-
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- }
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-
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- /*
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- * Special trace entry if we overflow the max depth:
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- */
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- if (i == sample_max_depth)
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- __trace_special(tr, data, -1, -1, -1);
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-
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- __trace_special(tr, data, 3, current->pid, i);
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-}
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-
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-static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer)
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-{
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- /* trace here */
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- timer_notify(get_irq_regs(), smp_processor_id());
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-
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- hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));
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-
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- return HRTIMER_RESTART;
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-}
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-
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-static void start_stack_timer(void *unused)
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-{
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- struct hrtimer *hrtimer = &__get_cpu_var(stack_trace_hrtimer);
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-
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- hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
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- hrtimer->function = stack_trace_timer_fn;
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-
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- hrtimer_start(hrtimer, ns_to_ktime(sample_period),
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- HRTIMER_MODE_REL_PINNED);
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-}
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-
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-static void start_stack_timers(void)
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-{
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- on_each_cpu(start_stack_timer, NULL, 1);
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-}
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-
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-static void stop_stack_timer(int cpu)
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-{
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- struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu);
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-
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- hrtimer_cancel(hrtimer);
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-}
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-
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-static void stop_stack_timers(void)
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-{
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- int cpu;
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-
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- for_each_online_cpu(cpu)
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- stop_stack_timer(cpu);
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-}
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-
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-static void stop_stack_trace(struct trace_array *tr)
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-{
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- mutex_lock(&sample_timer_lock);
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- stop_stack_timers();
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- tracer_enabled = 0;
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- mutex_unlock(&sample_timer_lock);
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-}
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-
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-static int stack_trace_init(struct trace_array *tr)
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-{
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- sysprof_trace = tr;
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-
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- tracing_start_cmdline_record();
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-
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- mutex_lock(&sample_timer_lock);
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- start_stack_timers();
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- tracer_enabled = 1;
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- mutex_unlock(&sample_timer_lock);
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- return 0;
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-}
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-
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-static void stack_trace_reset(struct trace_array *tr)
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-{
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- tracing_stop_cmdline_record();
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- stop_stack_trace(tr);
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-}
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-
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-static struct tracer stack_trace __read_mostly =
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-{
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- .name = "sysprof",
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- .init = stack_trace_init,
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- .reset = stack_trace_reset,
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-#ifdef CONFIG_FTRACE_SELFTEST
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- .selftest = trace_selftest_startup_sysprof,
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-#endif
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-};
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-
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-__init static int init_stack_trace(void)
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-{
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- return register_tracer(&stack_trace);
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-}
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-device_initcall(init_stack_trace);
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-
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-#define MAX_LONG_DIGITS 22
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-
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-static ssize_t
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-sysprof_sample_read(struct file *filp, char __user *ubuf,
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- size_t cnt, loff_t *ppos)
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-{
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- char buf[MAX_LONG_DIGITS];
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- int r;
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-
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- r = sprintf(buf, "%ld\n", nsecs_to_usecs(sample_period));
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-
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- return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
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-}
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-
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-static ssize_t
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-sysprof_sample_write(struct file *filp, const char __user *ubuf,
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- size_t cnt, loff_t *ppos)
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-{
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- char buf[MAX_LONG_DIGITS];
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- unsigned long val;
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-
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- if (cnt > MAX_LONG_DIGITS-1)
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- cnt = MAX_LONG_DIGITS-1;
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-
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- if (copy_from_user(&buf, ubuf, cnt))
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- return -EFAULT;
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-
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- buf[cnt] = 0;
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-
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- val = simple_strtoul(buf, NULL, 10);
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- /*
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- * Enforce a minimum sample period of 100 usecs:
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- */
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- if (val < 100)
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- val = 100;
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-
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- mutex_lock(&sample_timer_lock);
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- stop_stack_timers();
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- sample_period = val * 1000;
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- start_stack_timers();
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- mutex_unlock(&sample_timer_lock);
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-
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- return cnt;
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-}
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-
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-static const struct file_operations sysprof_sample_fops = {
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- .read = sysprof_sample_read,
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- .write = sysprof_sample_write,
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-};
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-
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-void init_tracer_sysprof_debugfs(struct dentry *d_tracer)
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-{
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-
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- trace_create_file("sysprof_sample_period", 0644,
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- d_tracer, NULL, &sysprof_sample_fops);
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-}
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Ingo Molnar