| /* | |
| * trace irqs off critical timings | |
| * | |
| * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
| * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
| * | |
| * From code in the latency_tracer, that is: | |
| * | |
| * Copyright (C) 2004-2006 Ingo Molnar | |
| * Copyright (C) 2004 Nadia Yvette Chambers | |
| */ | |
| #include <linux/kallsyms.h> | |
| #include <linux/uaccess.h> | |
| #include <linux/module.h> | |
| #include <linux/ftrace.h> | |
| #include "trace.h" | |
| #define CREATE_TRACE_POINTS | |
| #include <trace/events/preemptirq.h> | |
| #if defined(CONFIG_IRQSOFF_TRACER) || defined(CONFIG_PREEMPT_TRACER) | |
| static struct trace_array *irqsoff_trace __read_mostly; | |
| static int tracer_enabled __read_mostly; | |
| static DEFINE_PER_CPU(int, tracing_cpu); | |
| static DEFINE_RAW_SPINLOCK(max_trace_lock); | |
| enum { | |
| TRACER_IRQS_OFF = (1 << 1), | |
| TRACER_PREEMPT_OFF = (1 << 2), | |
| }; | |
| static int trace_type __read_mostly; | |
| static int save_flags; | |
| static void stop_irqsoff_tracer(struct trace_array *tr, int graph); | |
| static int start_irqsoff_tracer(struct trace_array *tr, int graph); | |
| #ifdef CONFIG_PREEMPT_TRACER | |
| static inline int | |
| preempt_trace(void) | |
| { | |
| return ((trace_type & TRACER_PREEMPT_OFF) && preempt_count()); | |
| } | |
| #else | |
| # define preempt_trace() (0) | |
| #endif | |
| #ifdef CONFIG_IRQSOFF_TRACER | |
| static inline int | |
| irq_trace(void) | |
| { | |
| return ((trace_type & TRACER_IRQS_OFF) && | |
| irqs_disabled()); | |
| } | |
| #else | |
| # define irq_trace() (0) | |
| #endif | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
| static int irqsoff_display_graph(struct trace_array *tr, int set); | |
| # define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH) | |
| #else | |
| static inline int irqsoff_display_graph(struct trace_array *tr, int set) | |
| { | |
| return -EINVAL; | |
| } | |
| # define is_graph(tr) false | |
| #endif | |
| /* | |
| * Sequence count - we record it when starting a measurement and | |
| * skip the latency if the sequence has changed - some other section | |
| * did a maximum and could disturb our measurement with serial console | |
| * printouts, etc. Truly coinciding maximum latencies should be rare | |
| * and what happens together happens separately as well, so this doesn't | |
| * decrease the validity of the maximum found: | |
| */ | |
| static __cacheline_aligned_in_smp unsigned long max_sequence; | |
| #ifdef CONFIG_FUNCTION_TRACER | |
| /* | |
| * Prologue for the preempt and irqs off function tracers. | |
| * | |
| * Returns 1 if it is OK to continue, and data->disabled is | |
| * incremented. | |
| * 0 if the trace is to be ignored, and data->disabled | |
| * is kept the same. | |
| * | |
| * Note, this function is also used outside this ifdef but | |
| * inside the #ifdef of the function graph tracer below. | |
| * This is OK, since the function graph tracer is | |
| * dependent on the function tracer. | |
| */ | |
| static int func_prolog_dec(struct trace_array *tr, | |
| struct trace_array_cpu **data, | |
| unsigned long *flags) | |
| { | |
| long disabled; | |
| int cpu; | |
| /* | |
| * Does not matter if we preempt. We test the flags | |
| * afterward, to see if irqs are disabled or not. | |
| * If we preempt and get a false positive, the flags | |
| * test will fail. | |
| */ | |
| cpu = raw_smp_processor_id(); | |
| if (likely(!per_cpu(tracing_cpu, cpu))) | |
| return 0; | |
| local_save_flags(*flags); | |
| /* | |
| * Slight chance to get a false positive on tracing_cpu, | |
| * although I'm starting to think there isn't a chance. | |
| * Leave this for now just to be paranoid. | |
| */ | |
| if (!irqs_disabled_flags(*flags) && !preempt_count()) | |
| return 0; | |
| *data = per_cpu_ptr(tr->trace_buffer.data, cpu); | |
| disabled = atomic_inc_return(&(*data)->disabled); | |
| if (likely(disabled == 1)) | |
| return 1; | |
| atomic_dec(&(*data)->disabled); | |
| return 0; | |
| } | |
| /* | |
| * irqsoff uses its own tracer function to keep the overhead down: | |
| */ | |
| static void | |
| irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, | |
| struct ftrace_ops *op, struct pt_regs *pt_regs) | |
| { | |
| struct trace_array *tr = irqsoff_trace; | |
| struct trace_array_cpu *data; | |
| unsigned long flags; | |
| if (!func_prolog_dec(tr, &data, &flags)) | |
| return; | |
| trace_function(tr, ip, parent_ip, flags, preempt_count()); | |
| atomic_dec(&data->disabled); | |
| } | |
| #endif /* CONFIG_FUNCTION_TRACER */ | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
| static int irqsoff_display_graph(struct trace_array *tr, int set) | |
| { | |
| int cpu; | |
| if (!(is_graph(tr) ^ set)) | |
| return 0; | |
| stop_irqsoff_tracer(irqsoff_trace, !set); | |
| for_each_possible_cpu(cpu) | |
| per_cpu(tracing_cpu, cpu) = 0; | |
| tr->max_latency = 0; | |
| tracing_reset_online_cpus(&irqsoff_trace->trace_buffer); | |
| return start_irqsoff_tracer(irqsoff_trace, set); | |
| } | |
| static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) | |
| { | |
| struct trace_array *tr = irqsoff_trace; | |
| struct trace_array_cpu *data; | |
| unsigned long flags; | |
| int ret; | |
| int pc; | |
| if (ftrace_graph_ignore_func(trace)) | |
| return 0; | |
| /* | |
| * Do not trace a function if it's filtered by set_graph_notrace. | |
| * Make the index of ret stack negative to indicate that it should | |
| * ignore further functions. But it needs its own ret stack entry | |
| * to recover the original index in order to continue tracing after | |
| * returning from the function. | |
| */ | |
| if (ftrace_graph_notrace_addr(trace->func)) | |
| return 1; | |
| if (!func_prolog_dec(tr, &data, &flags)) | |
| return 0; | |
| pc = preempt_count(); | |
| ret = __trace_graph_entry(tr, trace, flags, pc); | |
| atomic_dec(&data->disabled); | |
| return ret; | |
| } | |
| static void irqsoff_graph_return(struct ftrace_graph_ret *trace) | |
| { | |
| struct trace_array *tr = irqsoff_trace; | |
| struct trace_array_cpu *data; | |
| unsigned long flags; | |
| int pc; | |
| if (!func_prolog_dec(tr, &data, &flags)) | |
| return; | |
| pc = preempt_count(); | |
| __trace_graph_return(tr, trace, flags, pc); | |
| atomic_dec(&data->disabled); | |
| } | |
| static void irqsoff_trace_open(struct trace_iterator *iter) | |
| { | |
| if (is_graph(iter->tr)) | |
| graph_trace_open(iter); | |
| } | |
| static void irqsoff_trace_close(struct trace_iterator *iter) | |
| { | |
| if (iter->private) | |
| graph_trace_close(iter); | |
| } | |
| #define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \ | |
| TRACE_GRAPH_PRINT_PROC | \ | |
| TRACE_GRAPH_PRINT_ABS_TIME | \ | |
| TRACE_GRAPH_PRINT_DURATION) | |
| static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) | |
| { | |
| /* | |
| * In graph mode call the graph tracer output function, | |
| * otherwise go with the TRACE_FN event handler | |
| */ | |
| if (is_graph(iter->tr)) | |
| return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); | |
| return TRACE_TYPE_UNHANDLED; | |
| } | |
| static void irqsoff_print_header(struct seq_file *s) | |
| { | |
| struct trace_array *tr = irqsoff_trace; | |
| if (is_graph(tr)) | |
| print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); | |
| else | |
| trace_default_header(s); | |
| } | |
| static void | |
| __trace_function(struct trace_array *tr, | |
| unsigned long ip, unsigned long parent_ip, | |
| unsigned long flags, int pc) | |
| { | |
| if (is_graph(tr)) | |
| trace_graph_function(tr, ip, parent_ip, flags, pc); | |
| else | |
| trace_function(tr, ip, parent_ip, flags, pc); | |
| } | |
| #else | |
| #define __trace_function trace_function | |
| #ifdef CONFIG_FUNCTION_TRACER | |
| static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) | |
| { | |
| return -1; | |
| } | |
| #endif | |
| static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) | |
| { | |
| return TRACE_TYPE_UNHANDLED; | |
| } | |
| static void irqsoff_trace_open(struct trace_iterator *iter) { } | |
| static void irqsoff_trace_close(struct trace_iterator *iter) { } | |
| #ifdef CONFIG_FUNCTION_TRACER | |
| static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { } | |
| static void irqsoff_print_header(struct seq_file *s) | |
| { | |
| trace_default_header(s); | |
| } | |
| #else | |
| static void irqsoff_print_header(struct seq_file *s) | |
| { | |
| trace_latency_header(s); | |
| } | |
| #endif /* CONFIG_FUNCTION_TRACER */ | |
| #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
| /* | |
| * Should this new latency be reported/recorded? | |
| */ | |
| static bool report_latency(struct trace_array *tr, u64 delta) | |
| { | |
| if (tracing_thresh) { | |
| if (delta < tracing_thresh) | |
| return false; | |
| } else { | |
| if (delta <= tr->max_latency) | |
| return false; | |
| } | |
| return true; | |
| } | |
| static void | |
| check_critical_timing(struct trace_array *tr, | |
| struct trace_array_cpu *data, | |
| unsigned long parent_ip, | |
| int cpu) | |
| { | |
| u64 T0, T1, delta; | |
| unsigned long flags; | |
| int pc; | |
| T0 = data->preempt_timestamp; | |
| T1 = ftrace_now(cpu); | |
| delta = T1-T0; | |
| local_save_flags(flags); | |
| pc = preempt_count(); | |
| if (!report_latency(tr, delta)) | |
| goto out; | |
| raw_spin_lock_irqsave(&max_trace_lock, flags); | |
| /* check if we are still the max latency */ | |
| if (!report_latency(tr, delta)) | |
| goto out_unlock; | |
| __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); | |
| /* Skip 5 functions to get to the irq/preempt enable function */ | |
| __trace_stack(tr, flags, 5, pc); | |
| if (data->critical_sequence != max_sequence) | |
| goto out_unlock; | |
| data->critical_end = parent_ip; | |
| if (likely(!is_tracing_stopped())) { | |
| tr->max_latency = delta; | |
| update_max_tr_single(tr, current, cpu); | |
| } | |
| max_sequence++; | |
| out_unlock: | |
| raw_spin_unlock_irqrestore(&max_trace_lock, flags); | |
| out: | |
| data->critical_sequence = max_sequence; | |
| data->preempt_timestamp = ftrace_now(cpu); | |
| __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); | |
| } | |
| static inline void | |
| start_critical_timing(unsigned long ip, unsigned long parent_ip) | |
| { | |
| int cpu; | |
| struct trace_array *tr = irqsoff_trace; | |
| struct trace_array_cpu *data; | |
| unsigned long flags; | |
| if (!tracer_enabled || !tracing_is_enabled()) | |
| return; | |
| cpu = raw_smp_processor_id(); | |
| if (per_cpu(tracing_cpu, cpu)) | |
| return; | |
| data = per_cpu_ptr(tr->trace_buffer.data, cpu); | |
| if (unlikely(!data) || atomic_read(&data->disabled)) | |
| return; | |
| atomic_inc(&data->disabled); | |
| data->critical_sequence = max_sequence; | |
| data->preempt_timestamp = ftrace_now(cpu); | |
| data->critical_start = parent_ip ? : ip; | |
| local_save_flags(flags); | |
| __trace_function(tr, ip, parent_ip, flags, preempt_count()); | |
| per_cpu(tracing_cpu, cpu) = 1; | |
| atomic_dec(&data->disabled); | |
| } | |
| static inline void | |
| stop_critical_timing(unsigned long ip, unsigned long parent_ip) | |
| { | |
| int cpu; | |
| struct trace_array *tr = irqsoff_trace; | |
| struct trace_array_cpu *data; | |
| unsigned long flags; | |
| cpu = raw_smp_processor_id(); | |
| /* Always clear the tracing cpu on stopping the trace */ | |
| if (unlikely(per_cpu(tracing_cpu, cpu))) | |
| per_cpu(tracing_cpu, cpu) = 0; | |
| else | |
| return; | |
| if (!tracer_enabled || !tracing_is_enabled()) | |
| return; | |
| data = per_cpu_ptr(tr->trace_buffer.data, cpu); | |
| if (unlikely(!data) || | |
| !data->critical_start || atomic_read(&data->disabled)) | |
| return; | |
| atomic_inc(&data->disabled); | |
| local_save_flags(flags); | |
| __trace_function(tr, ip, parent_ip, flags, preempt_count()); | |
| check_critical_timing(tr, data, parent_ip ? : ip, cpu); | |
| data->critical_start = 0; | |
| atomic_dec(&data->disabled); | |
| } | |
| /* start and stop critical timings used to for stoppage (in idle) */ | |
| void start_critical_timings(void) | |
| { | |
| if (preempt_trace() || irq_trace()) | |
| start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); | |
| } | |
| EXPORT_SYMBOL_GPL(start_critical_timings); | |
| void stop_critical_timings(void) | |
| { | |
| if (preempt_trace() || irq_trace()) | |
| stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); | |
| } | |
| EXPORT_SYMBOL_GPL(stop_critical_timings); | |
| #ifdef CONFIG_IRQSOFF_TRACER | |
| #ifdef CONFIG_PROVE_LOCKING | |
| void time_hardirqs_on(unsigned long a0, unsigned long a1) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| stop_critical_timing(a0, a1); | |
| } | |
| void time_hardirqs_off(unsigned long a0, unsigned long a1) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| start_critical_timing(a0, a1); | |
| } | |
| #else /* !CONFIG_PROVE_LOCKING */ | |
| /* | |
| * We are only interested in hardirq on/off events: | |
| */ | |
| static inline void tracer_hardirqs_on(void) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); | |
| } | |
| static inline void tracer_hardirqs_off(void) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); | |
| } | |
| static inline void tracer_hardirqs_on_caller(unsigned long caller_addr) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| stop_critical_timing(CALLER_ADDR0, caller_addr); | |
| } | |
| static inline void tracer_hardirqs_off_caller(unsigned long caller_addr) | |
| { | |
| if (!preempt_trace() && irq_trace()) | |
| start_critical_timing(CALLER_ADDR0, caller_addr); | |
| } | |
| #endif /* CONFIG_PROVE_LOCKING */ | |
| #endif /* CONFIG_IRQSOFF_TRACER */ | |
| #ifdef CONFIG_PREEMPT_TRACER | |
| static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) | |
| { | |
| if (preempt_trace() && !irq_trace()) | |
| stop_critical_timing(a0, a1); | |
| } | |
| static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) | |
| { | |
| if (preempt_trace() && !irq_trace()) | |
| start_critical_timing(a0, a1); | |
| } | |
| #endif /* CONFIG_PREEMPT_TRACER */ | |
| #ifdef CONFIG_FUNCTION_TRACER | |
| static bool function_enabled; | |
| static int register_irqsoff_function(struct trace_array *tr, int graph, int set) | |
| { | |
| int ret; | |
| /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ | |
| if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION))) | |
| return 0; | |
| if (graph) | |
| ret = register_ftrace_graph(&irqsoff_graph_return, | |
| &irqsoff_graph_entry); | |
| else | |
| ret = register_ftrace_function(tr->ops); | |
| if (!ret) | |
| function_enabled = true; | |
| return ret; | |
| } | |
| static void unregister_irqsoff_function(struct trace_array *tr, int graph) | |
| { | |
| if (!function_enabled) | |
| return; | |
| if (graph) | |
| unregister_ftrace_graph(); | |
| else | |
| unregister_ftrace_function(tr->ops); | |
| function_enabled = false; | |
| } | |
| static int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) | |
| { | |
| if (!(mask & TRACE_ITER_FUNCTION)) | |
| return 0; | |
| if (set) | |
| register_irqsoff_function(tr, is_graph(tr), 1); | |
| else | |
| unregister_irqsoff_function(tr, is_graph(tr)); | |
| return 1; | |
| } | |
| #else | |
| static int register_irqsoff_function(struct trace_array *tr, int graph, int set) | |
| { | |
| return 0; | |
| } | |
| static void unregister_irqsoff_function(struct trace_array *tr, int graph) { } | |
| static inline int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) | |
| { | |
| return 0; | |
| } | |
| #endif /* CONFIG_FUNCTION_TRACER */ | |
| static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set) | |
| { | |
| struct tracer *tracer = tr->current_trace; | |
| if (irqsoff_function_set(tr, mask, set)) | |
| return 0; | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
| if (mask & TRACE_ITER_DISPLAY_GRAPH) | |
| return irqsoff_display_graph(tr, set); | |
| #endif | |
| return trace_keep_overwrite(tracer, mask, set); | |
| } | |
| static int start_irqsoff_tracer(struct trace_array *tr, int graph) | |
| { | |
| int ret; | |
| ret = register_irqsoff_function(tr, graph, 0); | |
| if (!ret && tracing_is_enabled()) | |
| tracer_enabled = 1; | |
| else | |
| tracer_enabled = 0; | |
| return ret; | |
| } | |
| static void stop_irqsoff_tracer(struct trace_array *tr, int graph) | |
| { | |
| tracer_enabled = 0; | |
| unregister_irqsoff_function(tr, graph); | |
| } | |
| static bool irqsoff_busy; | |
| static int __irqsoff_tracer_init(struct trace_array *tr) | |
| { | |
| if (irqsoff_busy) | |
| return -EBUSY; | |
| 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; | |
| irqsoff_trace = tr; | |
| /* make sure that the tracer is visible */ | |
| smp_wmb(); | |
| ftrace_init_array_ops(tr, irqsoff_tracer_call); | |
| /* Only toplevel instance supports graph tracing */ | |
| if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL && | |
| is_graph(tr)))) | |
| printk(KERN_ERR "failed to start irqsoff tracer\n"); | |
| irqsoff_busy = true; | |
| return 0; | |
| } | |
| static void irqsoff_tracer_reset(struct trace_array *tr) | |
| { | |
| int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; | |
| int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; | |
| stop_irqsoff_tracer(tr, is_graph(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); | |
| irqsoff_busy = false; | |
| } | |
| static void irqsoff_tracer_start(struct trace_array *tr) | |
| { | |
| tracer_enabled = 1; | |
| } | |
| static void irqsoff_tracer_stop(struct trace_array *tr) | |
| { | |
| tracer_enabled = 0; | |
| } | |
| #ifdef CONFIG_IRQSOFF_TRACER | |
| static int irqsoff_tracer_init(struct trace_array *tr) | |
| { | |
| trace_type = TRACER_IRQS_OFF; | |
| return __irqsoff_tracer_init(tr); | |
| } | |
| static struct tracer irqsoff_tracer __read_mostly = | |
| { | |
| .name = "irqsoff", | |
| .init = irqsoff_tracer_init, | |
| .reset = irqsoff_tracer_reset, | |
| .start = irqsoff_tracer_start, | |
| .stop = irqsoff_tracer_stop, | |
| .print_max = true, | |
| .print_header = irqsoff_print_header, | |
| .print_line = irqsoff_print_line, | |
| .flag_changed = irqsoff_flag_changed, | |
| #ifdef CONFIG_FTRACE_SELFTEST | |
| .selftest = trace_selftest_startup_irqsoff, | |
| #endif | |
| .open = irqsoff_trace_open, | |
| .close = irqsoff_trace_close, | |
| .allow_instances = true, | |
| .use_max_tr = true, | |
| }; | |
| # define register_irqsoff(trace) register_tracer(&trace) | |
| #else | |
| # define register_irqsoff(trace) do { } while (0) | |
| #endif | |
| #ifdef CONFIG_PREEMPT_TRACER | |
| static int preemptoff_tracer_init(struct trace_array *tr) | |
| { | |
| trace_type = TRACER_PREEMPT_OFF; | |
| return __irqsoff_tracer_init(tr); | |
| } | |
| static struct tracer preemptoff_tracer __read_mostly = | |
| { | |
| .name = "preemptoff", | |
| .init = preemptoff_tracer_init, | |
| .reset = irqsoff_tracer_reset, | |
| .start = irqsoff_tracer_start, | |
| .stop = irqsoff_tracer_stop, | |
| .print_max = true, | |
| .print_header = irqsoff_print_header, | |
| .print_line = irqsoff_print_line, | |
| .flag_changed = irqsoff_flag_changed, | |
| #ifdef CONFIG_FTRACE_SELFTEST | |
| .selftest = trace_selftest_startup_preemptoff, | |
| #endif | |
| .open = irqsoff_trace_open, | |
| .close = irqsoff_trace_close, | |
| .allow_instances = true, | |
| .use_max_tr = true, | |
| }; | |
| # define register_preemptoff(trace) register_tracer(&trace) | |
| #else | |
| # define register_preemptoff(trace) do { } while (0) | |
| #endif | |
| #if defined(CONFIG_IRQSOFF_TRACER) && \ | |
| defined(CONFIG_PREEMPT_TRACER) | |
| static int preemptirqsoff_tracer_init(struct trace_array *tr) | |
| { | |
| trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF; | |
| return __irqsoff_tracer_init(tr); | |
| } | |
| static struct tracer preemptirqsoff_tracer __read_mostly = | |
| { | |
| .name = "preemptirqsoff", | |
| .init = preemptirqsoff_tracer_init, | |
| .reset = irqsoff_tracer_reset, | |
| .start = irqsoff_tracer_start, | |
| .stop = irqsoff_tracer_stop, | |
| .print_max = true, | |
| .print_header = irqsoff_print_header, | |
| .print_line = irqsoff_print_line, | |
| .flag_changed = irqsoff_flag_changed, | |
| #ifdef CONFIG_FTRACE_SELFTEST | |
| .selftest = trace_selftest_startup_preemptirqsoff, | |
| #endif | |
| .open = irqsoff_trace_open, | |
| .close = irqsoff_trace_close, | |
| .allow_instances = true, | |
| .use_max_tr = true, | |
| }; | |
| # define register_preemptirqsoff(trace) register_tracer(&trace) | |
| #else | |
| # define register_preemptirqsoff(trace) do { } while (0) | |
| #endif | |
| __init static int init_irqsoff_tracer(void) | |
| { | |
| register_irqsoff(irqsoff_tracer); | |
| register_preemptoff(preemptoff_tracer); | |
| register_preemptirqsoff(preemptirqsoff_tracer); | |
| return 0; | |
| } | |
| core_initcall(init_irqsoff_tracer); | |
| #endif /* IRQSOFF_TRACER || PREEMPTOFF_TRACER */ | |
| #ifndef CONFIG_IRQSOFF_TRACER | |
| static inline void tracer_hardirqs_on(void) { } | |
| static inline void tracer_hardirqs_off(void) { } | |
| static inline void tracer_hardirqs_on_caller(unsigned long caller_addr) { } | |
| static inline void tracer_hardirqs_off_caller(unsigned long caller_addr) { } | |
| #endif | |
| #ifndef CONFIG_PREEMPT_TRACER | |
| static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { } | |
| static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { } | |
| #endif | |
| #if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PROVE_LOCKING) | |
| /* Per-cpu variable to prevent redundant calls when IRQs already off */ | |
| static DEFINE_PER_CPU(int, tracing_irq_cpu); | |
| void trace_hardirqs_on(void) | |
| { | |
| if (!this_cpu_read(tracing_irq_cpu)) | |
| return; | |
| trace_irq_enable_rcuidle(CALLER_ADDR0, CALLER_ADDR1); | |
| tracer_hardirqs_on(); | |
| this_cpu_write(tracing_irq_cpu, 0); | |
| } | |
| EXPORT_SYMBOL(trace_hardirqs_on); | |
| void trace_hardirqs_off(void) | |
| { | |
| if (this_cpu_read(tracing_irq_cpu)) | |
| return; | |
| this_cpu_write(tracing_irq_cpu, 1); | |
| trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1); | |
| tracer_hardirqs_off(); | |
| } | |
| EXPORT_SYMBOL(trace_hardirqs_off); | |
| __visible void trace_hardirqs_on_caller(unsigned long caller_addr) | |
| { | |
| if (!this_cpu_read(tracing_irq_cpu)) | |
| return; | |
| trace_irq_enable_rcuidle(CALLER_ADDR0, caller_addr); | |
| tracer_hardirqs_on_caller(caller_addr); | |
| this_cpu_write(tracing_irq_cpu, 0); | |
| } | |
| EXPORT_SYMBOL(trace_hardirqs_on_caller); | |
| __visible void trace_hardirqs_off_caller(unsigned long caller_addr) | |
| { | |
| if (this_cpu_read(tracing_irq_cpu)) | |
| return; | |
| this_cpu_write(tracing_irq_cpu, 1); | |
| trace_irq_disable_rcuidle(CALLER_ADDR0, caller_addr); | |
| tracer_hardirqs_off_caller(caller_addr); | |
| } | |
| EXPORT_SYMBOL(trace_hardirqs_off_caller); | |
| /* | |
| * Stubs: | |
| */ | |
| void trace_softirqs_on(unsigned long ip) | |
| { | |
| } | |
| void trace_softirqs_off(unsigned long ip) | |
| { | |
| } | |
| inline void print_irqtrace_events(struct task_struct *curr) | |
| { | |
| } | |
| #endif | |
| #if defined(CONFIG_PREEMPT_TRACER) || \ | |
| (defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_PREEMPTIRQ_EVENTS)) | |
| void trace_preempt_on(unsigned long a0, unsigned long a1) | |
| { | |
| trace_preempt_enable_rcuidle(a0, a1); | |
| tracer_preempt_on(a0, a1); | |
| } | |
| void trace_preempt_off(unsigned long a0, unsigned long a1) | |
| { | |
| trace_preempt_disable_rcuidle(a0, a1); | |
| tracer_preempt_off(a0, a1); | |
| } | |
| #endif |