Commit | Line | Data |
---|---|---|
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> | |
11 | ||
12 | #include "trace.h" | |
13 | ||
14 | static struct trace_array *boot_trace; | |
15 | static int trace_boot_enabled; | |
16 | ||
17 | ||
18 | /* Should be started after do_pre_smp_initcalls() in init/main.c */ | |
19 | void start_boot_trace(void) | |
20 | { | |
21 | trace_boot_enabled = 1; | |
22 | } | |
23 | ||
24 | void stop_boot_trace(struct trace_array *tr) | |
25 | { | |
26 | trace_boot_enabled = 0; | |
27 | } | |
28 | ||
29 | static void boot_trace_init(struct trace_array *tr) | |
30 | { | |
31 | int cpu; | |
32 | boot_trace = tr; | |
33 | ||
34 | trace_boot_enabled = 0; | |
35 | ||
36 | for_each_cpu_mask(cpu, cpu_possible_map) | |
3928a8a2 | 37 | tracing_reset(tr, cpu); |
d13744cd FW |
38 | } |
39 | ||
40 | static void boot_trace_ctrl_update(struct trace_array *tr) | |
41 | { | |
42 | if (tr->ctrl) | |
43 | start_boot_trace(); | |
44 | else | |
45 | stop_boot_trace(tr); | |
46 | } | |
47 | ||
9e9efffb | 48 | static enum print_line_t initcall_print_line(struct trace_iterator *iter) |
d13744cd | 49 | { |
9e9efffb | 50 | int ret; |
d13744cd | 51 | struct trace_entry *entry = iter->ent; |
777e208d SR |
52 | struct trace_boot *field = (struct trace_boot *)entry; |
53 | struct boot_trace *it = &field->initcall; | |
d13744cd FW |
54 | struct trace_seq *s = &iter->seq; |
55 | ||
9e9efffb | 56 | if (entry->type == TRACE_BOOT) { |
d13744cd FW |
57 | ret = trace_seq_printf(s, "%pF called from %i " |
58 | "returned %d after %lld msecs\n", | |
59 | it->func, it->caller, it->result, | |
60 | it->duration); | |
9e9efffb FW |
61 | if (ret) |
62 | return TRACE_TYPE_HANDLED; | |
63 | else | |
64 | return TRACE_TYPE_PARTIAL_LINE; | |
65 | } | |
66 | return TRACE_TYPE_UNHANDLED; | |
d13744cd FW |
67 | } |
68 | ||
69 | struct tracer boot_tracer __read_mostly = | |
70 | { | |
71 | .name = "initcall", | |
72 | .init = boot_trace_init, | |
73 | .reset = stop_boot_trace, | |
74 | .ctrl_update = boot_trace_ctrl_update, | |
75 | .print_line = initcall_print_line, | |
76 | }; | |
77 | ||
78 | ||
79 | void trace_boot(struct boot_trace *it) | |
80 | { | |
3928a8a2 | 81 | struct ring_buffer_event *event; |
777e208d | 82 | struct trace_boot *entry; |
d13744cd FW |
83 | struct trace_array_cpu *data; |
84 | unsigned long irq_flags; | |
85 | struct trace_array *tr = boot_trace; | |
86 | ||
87 | if (!trace_boot_enabled) | |
88 | return; | |
89 | ||
90 | preempt_disable(); | |
91 | data = tr->data[smp_processor_id()]; | |
92 | ||
3928a8a2 SR |
93 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
94 | &irq_flags); | |
95 | if (!event) | |
96 | goto out; | |
97 | entry = ring_buffer_event_data(event); | |
38697053 | 98 | tracing_generic_entry_update(&entry->ent, 0, 0); |
777e208d SR |
99 | entry->ent.type = TRACE_BOOT; |
100 | entry->initcall = *it; | |
3928a8a2 | 101 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
d13744cd | 102 | |
d13744cd FW |
103 | trace_wake_up(); |
104 | ||
3928a8a2 | 105 | out: |
d13744cd FW |
106 | preempt_enable(); |
107 | } |