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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 16:35:07 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-20 16:35:07 -0400
commit92b29b86fe2e183d44eb467e5e74a5f718ef2e43 (patch)
tree1bac8a1aa11d47322b66d10ec3a370016d843d06 /kernel/trace/trace_boot.c
parentb9d7ccf56be1ac77b71a284a1c0e6337f9a7aff0 (diff)
parent98d9c66ab07471006fd7910cb16453581c41a3e7 (diff)
Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (131 commits) tracing/fastboot: improve help text tracing/stacktrace: improve help text tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix bootgraph.pl initcall name regexp tracing/fastboot: fix issues and improve output of bootgraph.pl tracepoints: synchronize unregister static inline tracepoints: tracepoint_synchronize_unregister() ftrace: make ftrace_test_p6nop disassembler-friendly markers: fix synchronize marker unregister static inline tracing/fastboot: add better resolution to initcall debug/tracing trace: add build-time check to avoid overrunning hex buffer ftrace: fix hex output mode of ftrace tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix printk format typo in boot tracer ftrace: return an error when setting a nonexistent tracer ftrace: make some tracers reentrant ring-buffer: make reentrant ring-buffer: move page indexes into page headers tracing/fastboot: only trace non-module initcalls ftrace: move pc counter in irqtrace ... Manually fix conflicts: - init/main.c: initcall tracing - kernel/module.c: verbose level vs tracepoints - scripts/bootgraph.pl: fallout from cherry-picking commits.
Diffstat (limited to 'kernel/trace/trace_boot.c')
-rw-r--r--kernel/trace/trace_boot.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
new file mode 100644
index 000000000000..d0a5e50eeff2
--- /dev/null
+++ b/kernel/trace/trace_boot.c
@@ -0,0 +1,126 @@
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#include <linux/kallsyms.h>
12
13#include "trace.h"
14
15static struct trace_array *boot_trace;
16static int trace_boot_enabled;
17
18
19/* Should be started after do_pre_smp_initcalls() in init/main.c */
20void start_boot_trace(void)
21{
22 trace_boot_enabled = 1;
23}
24
25void stop_boot_trace(void)
26{
27 trace_boot_enabled = 0;
28}
29
30void reset_boot_trace(struct trace_array *tr)
31{
32 stop_boot_trace();
33}
34
35static void boot_trace_init(struct trace_array *tr)
36{
37 int cpu;
38 boot_trace = tr;
39
40 trace_boot_enabled = 0;
41
42 for_each_cpu_mask(cpu, cpu_possible_map)
43 tracing_reset(tr, cpu);
44}
45
46static void boot_trace_ctrl_update(struct trace_array *tr)
47{
48 if (tr->ctrl)
49 start_boot_trace();
50 else
51 stop_boot_trace();
52}
53
54static enum print_line_t initcall_print_line(struct trace_iterator *iter)
55{
56 int ret;
57 struct trace_entry *entry = iter->ent;
58 struct trace_boot *field = (struct trace_boot *)entry;
59 struct boot_trace *it = &field->initcall;
60 struct trace_seq *s = &iter->seq;
61 struct timespec calltime = ktime_to_timespec(it->calltime);
62 struct timespec rettime = ktime_to_timespec(it->rettime);
63
64 if (entry->type == TRACE_BOOT) {
65 ret = trace_seq_printf(s, "[%5ld.%09ld] calling %s @ %i\n",
66 calltime.tv_sec,
67 calltime.tv_nsec,
68 it->func, it->caller);
69 if (!ret)
70 return TRACE_TYPE_PARTIAL_LINE;
71
72 ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s "
73 "returned %d after %lld msecs\n",
74 rettime.tv_sec,
75 rettime.tv_nsec,
76 it->func, it->result, it->duration);
77
78 if (!ret)
79 return TRACE_TYPE_PARTIAL_LINE;
80 return TRACE_TYPE_HANDLED;
81 }
82 return TRACE_TYPE_UNHANDLED;
83}
84
85struct tracer boot_tracer __read_mostly =
86{
87 .name = "initcall",
88 .init = boot_trace_init,
89 .reset = reset_boot_trace,
90 .ctrl_update = boot_trace_ctrl_update,
91 .print_line = initcall_print_line,
92};
93
94void trace_boot(struct boot_trace *it, initcall_t fn)
95{
96 struct ring_buffer_event *event;
97 struct trace_boot *entry;
98 struct trace_array_cpu *data;
99 unsigned long irq_flags;
100 struct trace_array *tr = boot_trace;
101
102 if (!trace_boot_enabled)
103 return;
104
105 /* Get its name now since this function could
106 * disappear because it is in the .init section.
107 */
108 sprint_symbol(it->func, (unsigned long)fn);
109 preempt_disable();
110 data = tr->data[smp_processor_id()];
111
112 event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
113 &irq_flags);
114 if (!event)
115 goto out;
116 entry = ring_buffer_event_data(event);
117 tracing_generic_entry_update(&entry->ent, 0, 0);
118 entry->ent.type = TRACE_BOOT;
119 entry->initcall = *it;
120 ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
121
122 trace_wake_up();
123
124 out:
125 preempt_enable();
126}