Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

tracing: tracepoints for softirq entry/exit - tracepoints

Browse source 
Introduce softirq entry/exit tracepoints. These are useful for
augmenting existing tracers, and to figure out softirq frequencies and
timings.

[
  s/irq_softirq_/softirq_/ for trace point names and
  Fixed printf format in TRACE_FORMAT macro
   - Steven Rostedt
]

LKML-Reference: <20090312183603.GC3352@redhat.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This commit is contained in:
Jason Baron 2009-03-12 14:36:03 -04:00 committed by Steven Rostedt
parent 5d592b44b2
commit 39842323ce
2 changed files with 18 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
include/trace/irq_event_types.h
View file

@ -40,4 +40,16 @@ TRACE_EVENT(irq_handler_exit,
__entry->irq, __entry->ret ? "handled" : "unhandled")
);
TRACE_FORMAT(softirq_entry,
TP_PROTO(struct softirq_action *h, struct softirq_action *vec),
TP_ARGS(h, vec),
TP_FMT("softirq=%d action=%s", (int)(h - vec), softirq_to_name[h-vec])
);
TRACE_FORMAT(softirq_exit,
TP_PROTO(struct softirq_action *h, struct softirq_action *vec),
TP_ARGS(h, vec),
TP_FMT("softirq=%d action=%s", (int)(h - vec), softirq_to_name[h-vec])
);
#undef TRACE_SYSTEM

7
kernel/softirq.c
View file

@ -24,6 +24,7 @@
#include <linux/ftrace.h>
#include <linux/smp.h>
#include <linux/tick.h>
#include <trace/irq.h>
#include <asm/irq.h>
/*
@ -186,6 +187,9 @@ EXPORT_SYMBOL(local_bh_enable_ip);
*/
#define MAX_SOFTIRQ_RESTART 10
DEFINE_TRACE(softirq_entry);
DEFINE_TRACE(softirq_exit);
asmlinkage void __do_softirq(void)
{
struct softirq_action *h;
@ -212,8 +216,9 @@ asmlinkage void __do_softirq(void)
if (pending & 1) {
int prev_count = preempt_count();
trace_softirq_entry(h, softirq_vec);
h->action(h);
trace_softirq_exit(h, softirq_vec);
if (unlikely(prev_count != preempt_count())) {
printk(KERN_ERR "huh, entered softirq %td %s %p"
"with preempt_count %08x,"