137 lines
3.1 KiB
C
137 lines
3.1 KiB
C
/*
|
|
* kdb helper for dumping the ftrace buffer
|
|
*
|
|
* Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com>
|
|
*
|
|
* ftrace_dump_buf based on ftrace_dump:
|
|
* Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
|
|
* Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
|
|
*
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/kgdb.h>
|
|
#include <linux/kdb.h>
|
|
#include <linux/ftrace.h>
|
|
|
|
#include "../debug/kdb/kdb_private.h"
|
|
#include "trace.h"
|
|
#include "trace_output.h"
|
|
|
|
static void ftrace_dump_buf(int skip_lines, long cpu_file)
|
|
{
|
|
/* use static because iter can be a bit big for the stack */
|
|
static struct trace_iterator iter;
|
|
unsigned int old_userobj;
|
|
int cnt = 0, cpu;
|
|
|
|
trace_init_global_iter(&iter);
|
|
|
|
for_each_tracing_cpu(cpu) {
|
|
atomic_inc(&iter.tr->data[cpu]->disabled);
|
|
}
|
|
|
|
old_userobj = trace_flags;
|
|
|
|
/* don't look at user memory in panic mode */
|
|
trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
|
|
|
|
kdb_printf("Dumping ftrace buffer:\n");
|
|
|
|
/* reset all but tr, trace, and overruns */
|
|
memset(&iter.seq, 0,
|
|
sizeof(struct trace_iterator) -
|
|
offsetof(struct trace_iterator, seq));
|
|
iter.iter_flags |= TRACE_FILE_LAT_FMT;
|
|
iter.pos = -1;
|
|
|
|
if (cpu_file == TRACE_PIPE_ALL_CPU) {
|
|
for_each_tracing_cpu(cpu) {
|
|
iter.buffer_iter[cpu] =
|
|
ring_buffer_read_prepare(iter.tr->buffer, cpu);
|
|
ring_buffer_read_start(iter.buffer_iter[cpu]);
|
|
tracing_iter_reset(&iter, cpu);
|
|
}
|
|
} else {
|
|
iter.cpu_file = cpu_file;
|
|
iter.buffer_iter[cpu_file] =
|
|
ring_buffer_read_prepare(iter.tr->buffer, cpu_file);
|
|
ring_buffer_read_start(iter.buffer_iter[cpu_file]);
|
|
tracing_iter_reset(&iter, cpu_file);
|
|
}
|
|
if (!trace_empty(&iter))
|
|
trace_find_next_entry_inc(&iter);
|
|
while (!trace_empty(&iter)) {
|
|
if (!cnt)
|
|
kdb_printf("---------------------------------\n");
|
|
cnt++;
|
|
|
|
if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines)
|
|
print_trace_line(&iter);
|
|
if (!skip_lines)
|
|
trace_printk_seq(&iter.seq);
|
|
else
|
|
skip_lines--;
|
|
if (KDB_FLAG(CMD_INTERRUPT))
|
|
goto out;
|
|
}
|
|
|
|
if (!cnt)
|
|
kdb_printf(" (ftrace buffer empty)\n");
|
|
else
|
|
kdb_printf("---------------------------------\n");
|
|
|
|
out:
|
|
trace_flags = old_userobj;
|
|
|
|
for_each_tracing_cpu(cpu) {
|
|
atomic_dec(&iter.tr->data[cpu]->disabled);
|
|
}
|
|
|
|
for_each_tracing_cpu(cpu)
|
|
if (iter.buffer_iter[cpu])
|
|
ring_buffer_read_finish(iter.buffer_iter[cpu]);
|
|
}
|
|
|
|
/*
|
|
* kdb_ftdump - Dump the ftrace log buffer
|
|
*/
|
|
static int kdb_ftdump(int argc, const char **argv)
|
|
{
|
|
int skip_lines = 0;
|
|
long cpu_file;
|
|
char *cp;
|
|
|
|
if (argc > 2)
|
|
return KDB_ARGCOUNT;
|
|
|
|
if (argc) {
|
|
skip_lines = simple_strtol(argv[1], &cp, 0);
|
|
if (*cp)
|
|
skip_lines = 0;
|
|
}
|
|
|
|
if (argc == 2) {
|
|
cpu_file = simple_strtol(argv[2], &cp, 0);
|
|
if (*cp || cpu_file >= NR_CPUS || cpu_file < 0 ||
|
|
!cpu_online(cpu_file))
|
|
return KDB_BADINT;
|
|
} else {
|
|
cpu_file = TRACE_PIPE_ALL_CPU;
|
|
}
|
|
|
|
kdb_trap_printk++;
|
|
ftrace_dump_buf(skip_lines, cpu_file);
|
|
kdb_trap_printk--;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static __init int kdb_ftrace_register(void)
|
|
{
|
|
kdb_register_repeat("ftdump", kdb_ftdump, "[skip_#lines] [cpu]",
|
|
"Dump ftrace log", 0, KDB_REPEAT_NONE);
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(kdb_ftrace_register);
|