ftrace,kdb: Allow dumping a specific cpu's buffer with ftdump

In systems with more than one processor it is desirable to look at the
per cpu trace buffers.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Jason Wessel 2010-08-05 09:22:23 -05:00
parent 955b61e597
commit 19063c776f

View File

@ -17,7 +17,7 @@
#include "trace.h"
#include "trace_output.h"
static void ftrace_dump_buf(int skip_lines)
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;
@ -44,13 +44,20 @@ static void ftrace_dump_buf(int skip_lines)
iter.iter_flags |= TRACE_FILE_LAT_FMT;
iter.pos = -1;
for_each_tracing_cpu(cpu) {
iter.buffer_iter[cpu] =
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);
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)) {
@ -91,9 +98,10 @@ out:
static int kdb_ftdump(int argc, const char **argv)
{
int skip_lines = 0;
long cpu_file;
char *cp;
if (argc > 1)
if (argc > 2)
return KDB_ARGCOUNT;
if (argc) {
@ -102,8 +110,17 @@ static int kdb_ftdump(int argc, const char **argv)
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);
ftrace_dump_buf(skip_lines, cpu_file);
kdb_trap_printk--;
return 0;
@ -111,8 +128,8 @@ static int kdb_ftdump(int argc, const char **argv)
static __init int kdb_ftrace_register(void)
{
kdb_register_repeat("ftdump", kdb_ftdump, "", "Dump ftrace log",
0, KDB_REPEAT_NONE);
kdb_register_repeat("ftdump", kdb_ftdump, "[skip_#lines] [cpu]",
"Dump ftrace log", 0, KDB_REPEAT_NONE);
return 0;
}