ipv6: support for fib route lwtunnel encap attributes
[linux/fpc-iii.git] / kernel / trace / trace_kdb.c
blob3ccf5c2c1320131e5b1bc0bfe6a26b02edc402a8
1 /*
2 * kdb helper for dumping the ftrace buffer
4 * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com>
6 * ftrace_dump_buf based on ftrace_dump:
7 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
8 * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
11 #include <linux/init.h>
12 #include <linux/kgdb.h>
13 #include <linux/kdb.h>
14 #include <linux/ftrace.h>
16 #include "trace.h"
17 #include "trace_output.h"
19 static void ftrace_dump_buf(int skip_lines, long cpu_file)
21 /* use static because iter can be a bit big for the stack */
22 static struct trace_iterator iter;
23 static struct ring_buffer_iter *buffer_iter[CONFIG_NR_CPUS];
24 unsigned int old_userobj;
25 int cnt = 0, cpu;
27 trace_init_global_iter(&iter);
28 iter.buffer_iter = buffer_iter;
30 for_each_tracing_cpu(cpu) {
31 atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
34 old_userobj = trace_flags;
36 /* don't look at user memory in panic mode */
37 trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
39 kdb_printf("Dumping ftrace buffer:\n");
41 /* reset all but tr, trace, and overruns */
42 memset(&iter.seq, 0,
43 sizeof(struct trace_iterator) -
44 offsetof(struct trace_iterator, seq));
45 iter.iter_flags |= TRACE_FILE_LAT_FMT;
46 iter.pos = -1;
48 if (cpu_file == RING_BUFFER_ALL_CPUS) {
49 for_each_tracing_cpu(cpu) {
50 iter.buffer_iter[cpu] =
51 ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu);
52 ring_buffer_read_start(iter.buffer_iter[cpu]);
53 tracing_iter_reset(&iter, cpu);
55 } else {
56 iter.cpu_file = cpu_file;
57 iter.buffer_iter[cpu_file] =
58 ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu_file);
59 ring_buffer_read_start(iter.buffer_iter[cpu_file]);
60 tracing_iter_reset(&iter, cpu_file);
63 while (trace_find_next_entry_inc(&iter)) {
64 if (!cnt)
65 kdb_printf("---------------------------------\n");
66 cnt++;
68 if (!skip_lines) {
69 print_trace_line(&iter);
70 trace_printk_seq(&iter.seq);
71 } else {
72 skip_lines--;
75 if (KDB_FLAG(CMD_INTERRUPT))
76 goto out;
79 if (!cnt)
80 kdb_printf(" (ftrace buffer empty)\n");
81 else
82 kdb_printf("---------------------------------\n");
84 out:
85 trace_flags = old_userobj;
87 for_each_tracing_cpu(cpu) {
88 atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
91 for_each_tracing_cpu(cpu) {
92 if (iter.buffer_iter[cpu]) {
93 ring_buffer_read_finish(iter.buffer_iter[cpu]);
94 iter.buffer_iter[cpu] = NULL;
100 * kdb_ftdump - Dump the ftrace log buffer
102 static int kdb_ftdump(int argc, const char **argv)
104 int skip_lines = 0;
105 long cpu_file;
106 char *cp;
108 if (argc > 2)
109 return KDB_ARGCOUNT;
111 if (argc) {
112 skip_lines = simple_strtol(argv[1], &cp, 0);
113 if (*cp)
114 skip_lines = 0;
117 if (argc == 2) {
118 cpu_file = simple_strtol(argv[2], &cp, 0);
119 if (*cp || cpu_file >= NR_CPUS || cpu_file < 0 ||
120 !cpu_online(cpu_file))
121 return KDB_BADINT;
122 } else {
123 cpu_file = RING_BUFFER_ALL_CPUS;
126 kdb_trap_printk++;
127 ftrace_dump_buf(skip_lines, cpu_file);
128 kdb_trap_printk--;
130 return 0;
133 static __init int kdb_ftrace_register(void)
135 kdb_register_flags("ftdump", kdb_ftdump, "[skip_#lines] [cpu]",
136 "Dump ftrace log", 0, KDB_ENABLE_ALWAYS_SAFE);
137 return 0;
140 late_initcall(kdb_ftrace_register);