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817 lines
20 KiB
817 lines
20 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* trace task wakeup timings |
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* |
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* Copyright (C) 2007-2008 Steven Rostedt <[email protected]> |
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* Copyright (C) 2008 Ingo Molnar <[email protected]> |
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* |
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* Based on code from the latency_tracer, that is: |
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* |
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* Copyright (C) 2004-2006 Ingo Molnar |
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* Copyright (C) 2004 Nadia Yvette Chambers |
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*/ |
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#include <linux/module.h> |
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#include <linux/kallsyms.h> |
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#include <linux/uaccess.h> |
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#include <linux/ftrace.h> |
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#include <linux/sched/rt.h> |
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#include <linux/sched/deadline.h> |
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#include <trace/events/sched.h> |
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#include "trace.h" |
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static struct trace_array *wakeup_trace; |
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static int __read_mostly tracer_enabled; |
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static struct task_struct *wakeup_task; |
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static int wakeup_cpu; |
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static int wakeup_current_cpu; |
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static unsigned wakeup_prio = -1; |
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static bool wakeup_rt; |
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static bool wakeup_dl; |
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static bool tracing_dl; |
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static arch_spinlock_t wakeup_lock = |
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(arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
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static void wakeup_reset(struct trace_array *tr); |
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static void __wakeup_reset(struct trace_array *tr); |
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static int start_func_tracer(struct trace_array *tr, int graph); |
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static void stop_func_tracer(struct trace_array *tr, int graph); |
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static int save_flags; |
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER |
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# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH) |
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#else |
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# define is_graph(tr) false |
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#endif |
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#ifdef CONFIG_FUNCTION_TRACER |
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static bool function_enabled; |
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/* |
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* Prologue for the wakeup function tracers. |
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* |
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* Returns 1 if it is OK to continue, and preemption |
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* is disabled and data->disabled is incremented. |
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* 0 if the trace is to be ignored, and preemption |
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* is not disabled and data->disabled is |
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* kept the same. |
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* |
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* Note, this function is also used outside this ifdef but |
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* inside the #ifdef of the function graph tracer below. |
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* This is OK, since the function graph tracer is |
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* dependent on the function tracer. |
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*/ |
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static int |
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func_prolog_preempt_disable(struct trace_array *tr, |
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struct trace_array_cpu **data, |
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unsigned int *trace_ctx) |
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{ |
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long disabled; |
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int cpu; |
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if (likely(!wakeup_task)) |
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return 0; |
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*trace_ctx = tracing_gen_ctx(); |
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preempt_disable_notrace(); |
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cpu = raw_smp_processor_id(); |
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if (cpu != wakeup_current_cpu) |
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goto out_enable; |
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*data = per_cpu_ptr(tr->array_buffer.data, cpu); |
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disabled = atomic_inc_return(&(*data)->disabled); |
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if (unlikely(disabled != 1)) |
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goto out; |
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return 1; |
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out: |
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atomic_dec(&(*data)->disabled); |
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out_enable: |
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preempt_enable_notrace(); |
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return 0; |
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} |
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER |
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static int wakeup_display_graph(struct trace_array *tr, int set) |
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{ |
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if (!(is_graph(tr) ^ set)) |
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return 0; |
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stop_func_tracer(tr, !set); |
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wakeup_reset(wakeup_trace); |
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tr->max_latency = 0; |
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return start_func_tracer(tr, set); |
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} |
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static int wakeup_graph_entry(struct ftrace_graph_ent *trace) |
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{ |
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struct trace_array *tr = wakeup_trace; |
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struct trace_array_cpu *data; |
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unsigned int trace_ctx; |
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int ret = 0; |
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if (ftrace_graph_ignore_func(trace)) |
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return 0; |
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/* |
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* Do not trace a function if it's filtered by set_graph_notrace. |
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* Make the index of ret stack negative to indicate that it should |
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* ignore further functions. But it needs its own ret stack entry |
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* to recover the original index in order to continue tracing after |
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* returning from the function. |
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*/ |
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if (ftrace_graph_notrace_addr(trace->func)) |
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return 1; |
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if (!func_prolog_preempt_disable(tr, &data, &trace_ctx)) |
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return 0; |
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ret = __trace_graph_entry(tr, trace, trace_ctx); |
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atomic_dec(&data->disabled); |
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preempt_enable_notrace(); |
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return ret; |
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} |
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static void wakeup_graph_return(struct ftrace_graph_ret *trace) |
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{ |
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struct trace_array *tr = wakeup_trace; |
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struct trace_array_cpu *data; |
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unsigned int trace_ctx; |
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ftrace_graph_addr_finish(trace); |
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if (!func_prolog_preempt_disable(tr, &data, &trace_ctx)) |
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return; |
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__trace_graph_return(tr, trace, trace_ctx); |
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atomic_dec(&data->disabled); |
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preempt_enable_notrace(); |
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return; |
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} |
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static struct fgraph_ops fgraph_wakeup_ops = { |
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.entryfunc = &wakeup_graph_entry, |
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.retfunc = &wakeup_graph_return, |
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}; |
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static void wakeup_trace_open(struct trace_iterator *iter) |
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{ |
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if (is_graph(iter->tr)) |
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graph_trace_open(iter); |
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} |
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static void wakeup_trace_close(struct trace_iterator *iter) |
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{ |
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if (iter->private) |
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graph_trace_close(iter); |
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} |
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#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \ |
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TRACE_GRAPH_PRINT_CPU | \ |
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TRACE_GRAPH_PRINT_REL_TIME | \ |
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TRACE_GRAPH_PRINT_DURATION | \ |
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TRACE_GRAPH_PRINT_OVERHEAD | \ |
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TRACE_GRAPH_PRINT_IRQS) |
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static enum print_line_t wakeup_print_line(struct trace_iterator *iter) |
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{ |
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/* |
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* In graph mode call the graph tracer output function, |
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* otherwise go with the TRACE_FN event handler |
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*/ |
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if (is_graph(iter->tr)) |
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return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); |
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return TRACE_TYPE_UNHANDLED; |
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} |
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static void wakeup_print_header(struct seq_file *s) |
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{ |
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if (is_graph(wakeup_trace)) |
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print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); |
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else |
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trace_default_header(s); |
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} |
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#endif /* else CONFIG_FUNCTION_GRAPH_TRACER */ |
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/* |
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* wakeup uses its own tracer function to keep the overhead down: |
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*/ |
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static void |
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wakeup_tracer_call(unsigned long ip, unsigned long parent_ip, |
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struct ftrace_ops *op, struct ftrace_regs *fregs) |
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{ |
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struct trace_array *tr = wakeup_trace; |
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struct trace_array_cpu *data; |
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unsigned long flags; |
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unsigned int trace_ctx; |
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if (!func_prolog_preempt_disable(tr, &data, &trace_ctx)) |
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return; |
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local_irq_save(flags); |
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trace_function(tr, ip, parent_ip, trace_ctx); |
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local_irq_restore(flags); |
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atomic_dec(&data->disabled); |
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preempt_enable_notrace(); |
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} |
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static int register_wakeup_function(struct trace_array *tr, int graph, int set) |
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{ |
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int ret; |
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/* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ |
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if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION))) |
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return 0; |
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if (graph) |
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ret = register_ftrace_graph(&fgraph_wakeup_ops); |
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else |
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ret = register_ftrace_function(tr->ops); |
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if (!ret) |
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function_enabled = true; |
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return ret; |
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} |
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static void unregister_wakeup_function(struct trace_array *tr, int graph) |
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{ |
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if (!function_enabled) |
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return; |
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if (graph) |
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unregister_ftrace_graph(&fgraph_wakeup_ops); |
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else |
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unregister_ftrace_function(tr->ops); |
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function_enabled = false; |
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} |
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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set) |
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{ |
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if (!(mask & TRACE_ITER_FUNCTION)) |
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return 0; |
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if (set) |
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register_wakeup_function(tr, is_graph(tr), 1); |
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else |
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unregister_wakeup_function(tr, is_graph(tr)); |
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return 1; |
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} |
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#else /* CONFIG_FUNCTION_TRACER */ |
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static int register_wakeup_function(struct trace_array *tr, int graph, int set) |
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{ |
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return 0; |
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} |
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static void unregister_wakeup_function(struct trace_array *tr, int graph) { } |
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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set) |
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{ |
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return 0; |
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} |
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#endif /* else CONFIG_FUNCTION_TRACER */ |
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#ifndef CONFIG_FUNCTION_GRAPH_TRACER |
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static enum print_line_t wakeup_print_line(struct trace_iterator *iter) |
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{ |
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return TRACE_TYPE_UNHANDLED; |
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} |
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static void wakeup_trace_open(struct trace_iterator *iter) { } |
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static void wakeup_trace_close(struct trace_iterator *iter) { } |
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static void wakeup_print_header(struct seq_file *s) |
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{ |
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trace_default_header(s); |
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} |
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#endif /* !CONFIG_FUNCTION_GRAPH_TRACER */ |
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static void |
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__trace_function(struct trace_array *tr, |
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unsigned long ip, unsigned long parent_ip, |
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unsigned int trace_ctx) |
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{ |
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if (is_graph(tr)) |
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trace_graph_function(tr, ip, parent_ip, trace_ctx); |
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else |
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trace_function(tr, ip, parent_ip, trace_ctx); |
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} |
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static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set) |
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{ |
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struct tracer *tracer = tr->current_trace; |
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if (wakeup_function_set(tr, mask, set)) |
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return 0; |
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER |
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if (mask & TRACE_ITER_DISPLAY_GRAPH) |
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return wakeup_display_graph(tr, set); |
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#endif |
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return trace_keep_overwrite(tracer, mask, set); |
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} |
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static int start_func_tracer(struct trace_array *tr, int graph) |
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{ |
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int ret; |
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ret = register_wakeup_function(tr, graph, 0); |
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if (!ret && tracing_is_enabled()) |
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tracer_enabled = 1; |
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else |
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tracer_enabled = 0; |
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return ret; |
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} |
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static void stop_func_tracer(struct trace_array *tr, int graph) |
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{ |
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tracer_enabled = 0; |
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unregister_wakeup_function(tr, graph); |
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} |
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/* |
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* Should this new latency be reported/recorded? |
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*/ |
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static bool report_latency(struct trace_array *tr, u64 delta) |
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{ |
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if (tracing_thresh) { |
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if (delta < tracing_thresh) |
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return false; |
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} else { |
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if (delta <= tr->max_latency) |
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return false; |
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} |
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return true; |
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} |
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static void |
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probe_wakeup_migrate_task(void *ignore, struct task_struct *task, int cpu) |
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{ |
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if (task != wakeup_task) |
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return; |
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wakeup_current_cpu = cpu; |
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} |
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static void |
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tracing_sched_switch_trace(struct trace_array *tr, |
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struct task_struct *prev, |
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struct task_struct *next, |
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unsigned int trace_ctx) |
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{ |
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struct trace_event_call *call = &event_context_switch; |
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struct trace_buffer *buffer = tr->array_buffer.buffer; |
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struct ring_buffer_event *event; |
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struct ctx_switch_entry *entry; |
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event = trace_buffer_lock_reserve(buffer, TRACE_CTX, |
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sizeof(*entry), trace_ctx); |
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if (!event) |
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return; |
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entry = ring_buffer_event_data(event); |
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entry->prev_pid = prev->pid; |
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entry->prev_prio = prev->prio; |
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entry->prev_state = task_state_index(prev); |
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entry->next_pid = next->pid; |
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entry->next_prio = next->prio; |
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entry->next_state = task_state_index(next); |
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entry->next_cpu = task_cpu(next); |
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if (!call_filter_check_discard(call, entry, buffer, event)) |
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trace_buffer_unlock_commit(tr, buffer, event, trace_ctx); |
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} |
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static void |
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tracing_sched_wakeup_trace(struct trace_array *tr, |
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struct task_struct *wakee, |
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struct task_struct *curr, |
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unsigned int trace_ctx) |
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{ |
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struct trace_event_call *call = &event_wakeup; |
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struct ring_buffer_event *event; |
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struct ctx_switch_entry *entry; |
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struct trace_buffer *buffer = tr->array_buffer.buffer; |
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event = trace_buffer_lock_reserve(buffer, TRACE_WAKE, |
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sizeof(*entry), trace_ctx); |
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if (!event) |
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return; |
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entry = ring_buffer_event_data(event); |
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entry->prev_pid = curr->pid; |
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entry->prev_prio = curr->prio; |
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entry->prev_state = task_state_index(curr); |
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entry->next_pid = wakee->pid; |
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entry->next_prio = wakee->prio; |
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entry->next_state = task_state_index(wakee); |
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entry->next_cpu = task_cpu(wakee); |
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if (!call_filter_check_discard(call, entry, buffer, event)) |
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trace_buffer_unlock_commit(tr, buffer, event, trace_ctx); |
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} |
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static void notrace |
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probe_wakeup_sched_switch(void *ignore, bool preempt, |
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struct task_struct *prev, struct task_struct *next) |
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{ |
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struct trace_array_cpu *data; |
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u64 T0, T1, delta; |
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unsigned long flags; |
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long disabled; |
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int cpu; |
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unsigned int trace_ctx; |
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tracing_record_cmdline(prev); |
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if (unlikely(!tracer_enabled)) |
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return; |
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/* |
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* When we start a new trace, we set wakeup_task to NULL |
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* and then set tracer_enabled = 1. We want to make sure |
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* that another CPU does not see the tracer_enabled = 1 |
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* and the wakeup_task with an older task, that might |
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* actually be the same as next. |
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*/ |
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smp_rmb(); |
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if (next != wakeup_task) |
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return; |
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/* disable local data, not wakeup_cpu data */ |
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cpu = raw_smp_processor_id(); |
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disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled); |
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if (likely(disabled != 1)) |
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goto out; |
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local_irq_save(flags); |
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trace_ctx = tracing_gen_ctx_flags(flags); |
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arch_spin_lock(&wakeup_lock); |
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/* We could race with grabbing wakeup_lock */ |
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if (unlikely(!tracer_enabled || next != wakeup_task)) |
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goto out_unlock; |
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/* The task we are waiting for is waking up */ |
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data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu); |
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__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, trace_ctx); |
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tracing_sched_switch_trace(wakeup_trace, prev, next, trace_ctx); |
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__trace_stack(wakeup_trace, trace_ctx, 0); |
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T0 = data->preempt_timestamp; |
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T1 = ftrace_now(cpu); |
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delta = T1-T0; |
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if (!report_latency(wakeup_trace, delta)) |
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goto out_unlock; |
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if (likely(!is_tracing_stopped())) { |
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wakeup_trace->max_latency = delta; |
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update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu, NULL); |
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} |
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out_unlock: |
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__wakeup_reset(wakeup_trace); |
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arch_spin_unlock(&wakeup_lock); |
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local_irq_restore(flags); |
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out: |
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atomic_dec(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled); |
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} |
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static void __wakeup_reset(struct trace_array *tr) |
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{ |
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wakeup_cpu = -1; |
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wakeup_prio = -1; |
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tracing_dl = false; |
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if (wakeup_task) |
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put_task_struct(wakeup_task); |
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wakeup_task = NULL; |
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} |
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static void wakeup_reset(struct trace_array *tr) |
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{ |
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unsigned long flags; |
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tracing_reset_online_cpus(&tr->array_buffer); |
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local_irq_save(flags); |
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arch_spin_lock(&wakeup_lock); |
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__wakeup_reset(tr); |
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arch_spin_unlock(&wakeup_lock); |
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local_irq_restore(flags); |
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} |
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static void |
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probe_wakeup(void *ignore, struct task_struct *p) |
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{ |
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struct trace_array_cpu *data; |
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int cpu = smp_processor_id(); |
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long disabled; |
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unsigned int trace_ctx; |
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if (likely(!tracer_enabled)) |
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return; |
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tracing_record_cmdline(p); |
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tracing_record_cmdline(current); |
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/* |
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* Semantic is like this: |
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* - wakeup tracer handles all tasks in the system, independently |
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* from their scheduling class; |
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* - wakeup_rt tracer handles tasks belonging to sched_dl and |
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* sched_rt class; |
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* - wakeup_dl handles tasks belonging to sched_dl class only. |
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*/ |
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if (tracing_dl || (wakeup_dl && !dl_task(p)) || |
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(wakeup_rt && !dl_task(p) && !rt_task(p)) || |
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(!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio))) |
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return; |
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disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled); |
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if (unlikely(disabled != 1)) |
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goto out; |
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trace_ctx = tracing_gen_ctx(); |
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/* interrupts should be off from try_to_wake_up */ |
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arch_spin_lock(&wakeup_lock); |
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/* check for races. */ |
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if (!tracer_enabled || tracing_dl || |
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(!dl_task(p) && p->prio >= wakeup_prio)) |
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goto out_locked; |
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/* reset the trace */ |
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__wakeup_reset(wakeup_trace); |
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wakeup_cpu = task_cpu(p); |
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wakeup_current_cpu = wakeup_cpu; |
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wakeup_prio = p->prio; |
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/* |
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* Once you start tracing a -deadline task, don't bother tracing |
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* another task until the first one wakes up. |
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*/ |
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if (dl_task(p)) |
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tracing_dl = true; |
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else |
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tracing_dl = false; |
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wakeup_task = get_task_struct(p); |
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data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu); |
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data->preempt_timestamp = ftrace_now(cpu); |
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tracing_sched_wakeup_trace(wakeup_trace, p, current, trace_ctx); |
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__trace_stack(wakeup_trace, trace_ctx, 0); |
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/* |
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* We must be careful in using CALLER_ADDR2. But since wake_up |
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* is not called by an assembly function (where as schedule is) |
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* it should be safe to use it here. |
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*/ |
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__trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, trace_ctx); |
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out_locked: |
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arch_spin_unlock(&wakeup_lock); |
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out: |
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atomic_dec(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled); |
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} |
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static void start_wakeup_tracer(struct trace_array *tr) |
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{ |
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int ret; |
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|
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ret = register_trace_sched_wakeup(probe_wakeup, NULL); |
|
if (ret) { |
|
pr_info("wakeup trace: Couldn't activate tracepoint" |
|
" probe to kernel_sched_wakeup\n"); |
|
return; |
|
} |
|
|
|
ret = register_trace_sched_wakeup_new(probe_wakeup, NULL); |
|
if (ret) { |
|
pr_info("wakeup trace: Couldn't activate tracepoint" |
|
" probe to kernel_sched_wakeup_new\n"); |
|
goto fail_deprobe; |
|
} |
|
|
|
ret = register_trace_sched_switch(probe_wakeup_sched_switch, NULL); |
|
if (ret) { |
|
pr_info("sched trace: Couldn't activate tracepoint" |
|
" probe to kernel_sched_switch\n"); |
|
goto fail_deprobe_wake_new; |
|
} |
|
|
|
ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL); |
|
if (ret) { |
|
pr_info("wakeup trace: Couldn't activate tracepoint" |
|
" probe to kernel_sched_migrate_task\n"); |
|
goto fail_deprobe_sched_switch; |
|
} |
|
|
|
wakeup_reset(tr); |
|
|
|
/* |
|
* Don't let the tracer_enabled = 1 show up before |
|
* the wakeup_task is reset. This may be overkill since |
|
* wakeup_reset does a spin_unlock after setting the |
|
* wakeup_task to NULL, but I want to be safe. |
|
* This is a slow path anyway. |
|
*/ |
|
smp_wmb(); |
|
|
|
if (start_func_tracer(tr, is_graph(tr))) |
|
printk(KERN_ERR "failed to start wakeup tracer\n"); |
|
|
|
return; |
|
fail_deprobe_sched_switch: |
|
unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); |
|
fail_deprobe_wake_new: |
|
unregister_trace_sched_wakeup_new(probe_wakeup, NULL); |
|
fail_deprobe: |
|
unregister_trace_sched_wakeup(probe_wakeup, NULL); |
|
} |
|
|
|
static void stop_wakeup_tracer(struct trace_array *tr) |
|
{ |
|
tracer_enabled = 0; |
|
stop_func_tracer(tr, is_graph(tr)); |
|
unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); |
|
unregister_trace_sched_wakeup_new(probe_wakeup, NULL); |
|
unregister_trace_sched_wakeup(probe_wakeup, NULL); |
|
unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL); |
|
} |
|
|
|
static bool wakeup_busy; |
|
|
|
static int __wakeup_tracer_init(struct trace_array *tr) |
|
{ |
|
save_flags = tr->trace_flags; |
|
|
|
/* non overwrite screws up the latency tracers */ |
|
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); |
|
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1); |
|
|
|
tr->max_latency = 0; |
|
wakeup_trace = tr; |
|
ftrace_init_array_ops(tr, wakeup_tracer_call); |
|
start_wakeup_tracer(tr); |
|
|
|
wakeup_busy = true; |
|
return 0; |
|
} |
|
|
|
static int wakeup_tracer_init(struct trace_array *tr) |
|
{ |
|
if (wakeup_busy) |
|
return -EBUSY; |
|
|
|
wakeup_dl = false; |
|
wakeup_rt = false; |
|
return __wakeup_tracer_init(tr); |
|
} |
|
|
|
static int wakeup_rt_tracer_init(struct trace_array *tr) |
|
{ |
|
if (wakeup_busy) |
|
return -EBUSY; |
|
|
|
wakeup_dl = false; |
|
wakeup_rt = true; |
|
return __wakeup_tracer_init(tr); |
|
} |
|
|
|
static int wakeup_dl_tracer_init(struct trace_array *tr) |
|
{ |
|
if (wakeup_busy) |
|
return -EBUSY; |
|
|
|
wakeup_dl = true; |
|
wakeup_rt = false; |
|
return __wakeup_tracer_init(tr); |
|
} |
|
|
|
static void wakeup_tracer_reset(struct trace_array *tr) |
|
{ |
|
int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; |
|
int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; |
|
|
|
stop_wakeup_tracer(tr); |
|
/* make sure we put back any tasks we are tracing */ |
|
wakeup_reset(tr); |
|
|
|
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); |
|
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); |
|
ftrace_reset_array_ops(tr); |
|
wakeup_busy = false; |
|
} |
|
|
|
static void wakeup_tracer_start(struct trace_array *tr) |
|
{ |
|
wakeup_reset(tr); |
|
tracer_enabled = 1; |
|
} |
|
|
|
static void wakeup_tracer_stop(struct trace_array *tr) |
|
{ |
|
tracer_enabled = 0; |
|
} |
|
|
|
static struct tracer wakeup_tracer __read_mostly = |
|
{ |
|
.name = "wakeup", |
|
.init = wakeup_tracer_init, |
|
.reset = wakeup_tracer_reset, |
|
.start = wakeup_tracer_start, |
|
.stop = wakeup_tracer_stop, |
|
.print_max = true, |
|
.print_header = wakeup_print_header, |
|
.print_line = wakeup_print_line, |
|
.flag_changed = wakeup_flag_changed, |
|
#ifdef CONFIG_FTRACE_SELFTEST |
|
.selftest = trace_selftest_startup_wakeup, |
|
#endif |
|
.open = wakeup_trace_open, |
|
.close = wakeup_trace_close, |
|
.allow_instances = true, |
|
.use_max_tr = true, |
|
}; |
|
|
|
static struct tracer wakeup_rt_tracer __read_mostly = |
|
{ |
|
.name = "wakeup_rt", |
|
.init = wakeup_rt_tracer_init, |
|
.reset = wakeup_tracer_reset, |
|
.start = wakeup_tracer_start, |
|
.stop = wakeup_tracer_stop, |
|
.print_max = true, |
|
.print_header = wakeup_print_header, |
|
.print_line = wakeup_print_line, |
|
.flag_changed = wakeup_flag_changed, |
|
#ifdef CONFIG_FTRACE_SELFTEST |
|
.selftest = trace_selftest_startup_wakeup, |
|
#endif |
|
.open = wakeup_trace_open, |
|
.close = wakeup_trace_close, |
|
.allow_instances = true, |
|
.use_max_tr = true, |
|
}; |
|
|
|
static struct tracer wakeup_dl_tracer __read_mostly = |
|
{ |
|
.name = "wakeup_dl", |
|
.init = wakeup_dl_tracer_init, |
|
.reset = wakeup_tracer_reset, |
|
.start = wakeup_tracer_start, |
|
.stop = wakeup_tracer_stop, |
|
.print_max = true, |
|
.print_header = wakeup_print_header, |
|
.print_line = wakeup_print_line, |
|
.flag_changed = wakeup_flag_changed, |
|
#ifdef CONFIG_FTRACE_SELFTEST |
|
.selftest = trace_selftest_startup_wakeup, |
|
#endif |
|
.open = wakeup_trace_open, |
|
.close = wakeup_trace_close, |
|
.allow_instances = true, |
|
.use_max_tr = true, |
|
}; |
|
|
|
__init static int init_wakeup_tracer(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_tracer(&wakeup_tracer); |
|
if (ret) |
|
return ret; |
|
|
|
ret = register_tracer(&wakeup_rt_tracer); |
|
if (ret) |
|
return ret; |
|
|
|
ret = register_tracer(&wakeup_dl_tracer); |
|
if (ret) |
|
return ret; |
|
|
|
return 0; |
|
} |
|
core_initcall(init_wakeup_tracer);
|
|
|