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Commit | Line | Data |
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d13744cd FW |
1 | /* |
2 | * ring buffer based initcalls tracer | |
3 | * | |
4 | * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> | |
5 | * | |
6 | */ | |
7 | ||
8 | #include <linux/init.h> | |
9 | #include <linux/debugfs.h> | |
10 | #include <linux/ftrace.h> | |
5601020f | 11 | #include <linux/kallsyms.h> |
d13744cd FW |
12 | |
13 | #include "trace.h" | |
14 | ||
15 | static struct trace_array *boot_trace; | |
71566a0d | 16 | static bool pre_initcalls_finished; |
d13744cd | 17 | |
71566a0d FW |
18 | /* Tells the boot tracer that the pre_smp_initcalls are finished. |
19 | * So we are ready . | |
20 | * It doesn't enable sched events tracing however. | |
21 | * You have to call enable_boot_trace to do so. | |
22 | */ | |
d13744cd FW |
23 | void start_boot_trace(void) |
24 | { | |
71566a0d FW |
25 | pre_initcalls_finished = true; |
26 | } | |
27 | ||
28 | void enable_boot_trace(void) | |
29 | { | |
d7ad44b6 | 30 | if (pre_initcalls_finished) |
e168e051 | 31 | tracing_start_sched_switch_record(); |
d13744cd FW |
32 | } |
33 | ||
71566a0d | 34 | void disable_boot_trace(void) |
d13744cd | 35 | { |
d7ad44b6 | 36 | if (pre_initcalls_finished) |
e168e051 | 37 | tracing_stop_sched_switch_record(); |
d13744cd FW |
38 | } |
39 | ||
79a9d461 | 40 | static void reset_boot_trace(struct trace_array *tr) |
097d036a | 41 | { |
75f5c47d SR |
42 | int cpu; |
43 | ||
44 | tr->time_start = ftrace_now(tr->cpu); | |
45 | ||
46 | for_each_online_cpu(cpu) | |
47 | tracing_reset(tr, cpu); | |
097d036a FW |
48 | } |
49 | ||
d13744cd FW |
50 | static void boot_trace_init(struct trace_array *tr) |
51 | { | |
52 | int cpu; | |
53 | boot_trace = tr; | |
54 | ||
d13744cd | 55 | for_each_cpu_mask(cpu, cpu_possible_map) |
3928a8a2 | 56 | tracing_reset(tr, cpu); |
d7ad44b6 | 57 | |
e168e051 | 58 | tracing_sched_switch_assign_trace(tr); |
d13744cd FW |
59 | } |
60 | ||
9e9efffb | 61 | static enum print_line_t initcall_print_line(struct trace_iterator *iter) |
d13744cd | 62 | { |
9e9efffb | 63 | int ret; |
d13744cd | 64 | struct trace_entry *entry = iter->ent; |
777e208d SR |
65 | struct trace_boot *field = (struct trace_boot *)entry; |
66 | struct boot_trace *it = &field->initcall; | |
d13744cd | 67 | struct trace_seq *s = &iter->seq; |
cb5ab742 FW |
68 | struct timespec calltime = ktime_to_timespec(it->calltime); |
69 | struct timespec rettime = ktime_to_timespec(it->rettime); | |
d13744cd | 70 | |
9e9efffb | 71 | if (entry->type == TRACE_BOOT) { |
8a5d900c | 72 | ret = trace_seq_printf(s, "[%5ld.%09ld] calling %s @ %i\n", |
cb5ab742 FW |
73 | calltime.tv_sec, |
74 | calltime.tv_nsec, | |
75 | it->func, it->caller); | |
76 | if (!ret) | |
9e9efffb | 77 | return TRACE_TYPE_PARTIAL_LINE; |
5601020f | 78 | |
8a5d900c | 79 | ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s " |
cb5ab742 FW |
80 | "returned %d after %lld msecs\n", |
81 | rettime.tv_sec, | |
82 | rettime.tv_nsec, | |
83 | it->func, it->result, it->duration); | |
5601020f | 84 | |
cb5ab742 FW |
85 | if (!ret) |
86 | return TRACE_TYPE_PARTIAL_LINE; | |
87 | return TRACE_TYPE_HANDLED; | |
9e9efffb FW |
88 | } |
89 | return TRACE_TYPE_UNHANDLED; | |
d13744cd FW |
90 | } |
91 | ||
92 | struct tracer boot_tracer __read_mostly = | |
93 | { | |
94 | .name = "initcall", | |
95 | .init = boot_trace_init, | |
097d036a | 96 | .reset = reset_boot_trace, |
d13744cd FW |
97 | .print_line = initcall_print_line, |
98 | }; | |
99 | ||
5601020f | 100 | void trace_boot(struct boot_trace *it, initcall_t fn) |
d13744cd | 101 | { |
3928a8a2 | 102 | struct ring_buffer_event *event; |
777e208d | 103 | struct trace_boot *entry; |
d13744cd FW |
104 | struct trace_array_cpu *data; |
105 | unsigned long irq_flags; | |
106 | struct trace_array *tr = boot_trace; | |
107 | ||
71566a0d | 108 | if (!pre_initcalls_finished) |
d13744cd FW |
109 | return; |
110 | ||
5601020f FW |
111 | /* Get its name now since this function could |
112 | * disappear because it is in the .init section. | |
113 | */ | |
114 | sprint_symbol(it->func, (unsigned long)fn); | |
d13744cd FW |
115 | preempt_disable(); |
116 | data = tr->data[smp_processor_id()]; | |
117 | ||
3928a8a2 SR |
118 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
119 | &irq_flags); | |
120 | if (!event) | |
121 | goto out; | |
122 | entry = ring_buffer_event_data(event); | |
38697053 | 123 | tracing_generic_entry_update(&entry->ent, 0, 0); |
777e208d SR |
124 | entry->ent.type = TRACE_BOOT; |
125 | entry->initcall = *it; | |
3928a8a2 | 126 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
d13744cd | 127 | |
d13744cd FW |
128 | trace_wake_up(); |
129 | ||
3928a8a2 | 130 | out: |
d13744cd FW |
131 | preempt_enable(); |
132 | } |