perf/trace: Add ability to set a target task for events
A few events are interesting not only for a current task.
For example, sched_stat_* events are interesting for a task
which wakes up. For this reason, it will be good if such
events will be delivered to a target task too.
Now a target task can be set by using __perf_task().
The original idea and a draft patch belongs to Peter Zijlstra.
I need these events for profiling sleep times. sched_switch is used for
getting callchains and sched_stat_* is used for getting time periods.
These events are combined in user space, then it can be analyzed by
perf tools.
Inspired-by: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arun Sharma <asharma@fb.com>
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342016098-213063-1-git-send-email-avagin@openvz.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index af961d6..642928c 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -306,9 +306,10 @@
static inline void
perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
- u64 count, struct pt_regs *regs, void *head)
+ u64 count, struct pt_regs *regs, void *head,
+ struct task_struct *task)
{
- perf_tp_event(addr, count, raw_data, size, regs, head, rctx);
+ perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
}
#endif
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 76c5c8b..7602ccb 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1272,7 +1272,8 @@
extern void perf_event_init(void);
extern void perf_tp_event(u64 addr, u64 count, void *record,
int entry_size, struct pt_regs *regs,
- struct hlist_head *head, int rctx);
+ struct hlist_head *head, int rctx,
+ struct task_struct *task);
extern void perf_bp_event(struct perf_event *event, void *data);
#ifndef perf_misc_flags
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index ea7a203..5a8671e 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -73,6 +73,9 @@
__entry->prio = p->prio;
__entry->success = success;
__entry->target_cpu = task_cpu(p);
+ )
+ TP_perf_assign(
+ __perf_task(p);
),
TP_printk("comm=%s pid=%d prio=%d success=%d target_cpu=%03d",
@@ -325,6 +328,7 @@
)
TP_perf_assign(
__perf_count(delay);
+ __perf_task(tsk);
),
TP_printk("comm=%s pid=%d delay=%Lu [ns]",
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index c6bc2fa..a763888 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -712,6 +712,9 @@
#undef __perf_count
#define __perf_count(c) __count = (c)
+#undef __perf_task
+#define __perf_task(t) __task = (t)
+
#undef TP_perf_assign
#define TP_perf_assign(args...) args
@@ -725,6 +728,7 @@
struct ftrace_raw_##call *entry; \
struct pt_regs __regs; \
u64 __addr = 0, __count = 1; \
+ struct task_struct *__task = NULL; \
struct hlist_head *head; \
int __entry_size; \
int __data_size; \
@@ -752,7 +756,7 @@
\
head = this_cpu_ptr(event_call->perf_events); \
perf_trace_buf_submit(entry, __entry_size, rctx, __addr, \
- __count, &__regs, head); \
+ __count, &__regs, head, __task); \
}
/*