[RFC PATCH 09/22 -v2] mcount tracer show task comm and pid

Steven Rostedt
2008-01-09T23:31:04Z

[-- Attachment #1: mcount-tracer-add-pid-comm.patch --]
[-- Type: text/plain, Size: 2680 bytes --]

This adds the task comm and pid to the trace output. This gives the
output like:

CPU 0: sshd:2605 [<ffffffff80251858>] remove_wait_queue+0xc/0x4a <-- [<ffffffff802ad7be>] free_poll_entry+0x1e/0x2a
CPU 2: bash:2610 [<ffffffff8038c3aa>] tty_check_change+0x9/0xb6 <-- [<ffffffff8038d295>] tty_ioctl+0x59f/0xcdd
CPU 0: sshd:2605 [<ffffffff80491ec6>] _spin_lock_irqsave+0xe/0x81 <-- [<ffffffff80251863>] remove_wait_queue+0x17/0x4a
CPU 2: bash:2610 [<ffffffff8024e2f7>] find_vpid+0x9/0x24 <-- [<ffffffff8038d325>] tty_ioctl+0x62f/0xcdd
CPU 0: sshd:2605 [<ffffffff804923ec>] _spin_unlock_irqrestore+0x9/0x3a <-- [<ffffffff80251891>] remove_wait_queue+0x45/0x4a
CPU 0: sshd:2605 [<ffffffff802a18b3>] fput+0x9/0x1b <-- [<ffffffff802ad7c6>] free_poll_entry+0x26/0x2a

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
lib/tracing/tracer.c | 6 +++++-
lib/tracing/tracer.h | 3 +++
2 files changed, 8 insertions(+), 1 deletion(-)

Index: linux-compile-i386.git/lib/tracing/tracer.c
===================================================================
--- linux-compile-i386.git.orig/lib/tracing/tracer.c 2008-01-09 14:12:52.000000000 -0500
+++ linux-compile-i386.git/lib/tracing/tracer.c 2008-01-09 15:17:39.000000000 -0500
@@ -34,6 +34,7 @@ mctracer_add_trace_entry(struct mctracer
{
unsigned long idx, idx_next;
struct mctracer_entry *entry;
+ struct task_struct *tsk = current;

idx = tr->trace_idx[cpu];
idx_next = idx + 1;
@@ -52,6 +53,8 @@ mctracer_add_trace_entry(struct mctracer
entry->idx = atomic_inc_return(&tr->cnt);
entry->ip = ip;
entry->parent_ip = parent_ip;
+ entry->pid = tsk->pid;
+ memcpy(entry->comm, tsk->comm, TASK_COMM_LEN);
}

static notrace void trace_function(const unsigned long ip,
@@ -217,7 +220,8 @@ static int s_show(struct seq_file *m, vo
if (iter->ent == NULL) {
seq_printf(m, "mctracer:\n");
} else {
- seq_printf(m, " CPU %d: ", iter->cpu);
+ seq_printf(m, "CPU %d: ", iter->cpu);
+ seq_printf(m, "%s:%d ", iter->ent->comm, iter->ent->pid);
seq_print_ip_sym(m, iter->ent->ip);
if (iter->ent->parent_ip) {
seq_printf(m, " <-- ");
Index: linux-compile-i386.git/lib/tracing/tracer.h
===================================================================
--- linux-compile-i386.git.orig/lib/tracing/tracer.h 2008-01-09 14:11:35.000000000 -0500
+++ linux-compile-i386.git/lib/tracing/tracer.h 2008-01-09 15:17:39.000000000 -0500
@@ -2,11 +2,14 @@
#define _LINUX_MCOUNT_TRACER_H

#include <asm/atomic.h>
+#include <linux/sched.h>

struct mctracer_entry {
unsigned long idx;
unsigned long ip;
unsigned long parent_ip;
+ char comm[TASK_COMM_LEN];
+ pid_t pid;
};

struct mctracer_trace {

--