+++ /dev/null
-From: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
-Subject: LTTng instrumentation - scheduler
-
-Original patch header:
- LTTng instrumentation - scheduler
-
- Instrument the scheduler activity (sched_switch, migration, wakeups, wait for a
- task, signal delivery) and process/thread creation/destruction (fork, exit,
- kthread stop). Actually, kthread creation is not instrumented in this patch
- because it is architecture dependent. It allows to connect tracers such as
- ftrace which detects scheduling latencies, good/bad scheduler decisions. Tools
- like LTTng can export this scheduler information along with instrumentation of
- the rest of the kernel activity to perform post-mortem analysis on the scheduler
- activity.
-
- About the performance impact of tracepoints (which is comparable to markers),
- even without immediate values optimizations, tests done by Hideo Aoki on ia64
- show no regression. His test case was using hackbench on a kernel where
- scheduler instrumentation (about 5 events in code scheduler code) was added.
- See the "Tracepoints" patch header for performance result detail.
-
- Changelog :
- - Change instrumentation location and parameter to match ftrace instrumentation,
- previously done with kernel markers.
-
- Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
- CC: 'Peter Zijlstra' <peterz@infradead.org>
- CC: 'Steven Rostedt' <rostedt@goodmis.org>
- CC: Thomas Gleixner <tglx@linutronix.de>
- CC: Masami Hiramatsu <mhiramat@redhat.com>
- CC: "Frank Ch. Eigler" <fche@redhat.com>
- CC: 'Ingo Molnar' <mingo@elte.hu>
- CC: 'Hideo AOKI' <haoki@redhat.com>
- CC: Takashi Nishiie <t-nishiie@np.css.fujitsu.com>
- CC: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
-
-Acked-by: Jan Blunck <jblunck@suse.de>
----
----
- include/trace/sched.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
- kernel/exit.c | 10 +++++++++-
- kernel/fork.c | 3 +++
- kernel/kthread.c | 5 +++++
- kernel/sched.c | 17 ++++++-----------
- kernel/signal.c | 3 +++
- 6 files changed, 71 insertions(+), 12 deletions(-)
-
---- /dev/null
-+++ b/include/trace/sched.h
-@@ -0,0 +1,45 @@
-+#ifndef _TRACE_SCHED_H
-+#define _TRACE_SCHED_H
-+
-+#include <linux/sched.h>
-+#include <linux/tracepoint.h>
-+
-+DEFINE_TRACE(sched_kthread_stop,
-+ TPPROTO(struct task_struct *t),
-+ TPARGS(t));
-+DEFINE_TRACE(sched_kthread_stop_ret,
-+ TPPROTO(int ret),
-+ TPARGS(ret));
-+DEFINE_TRACE(sched_wait_task,
-+ TPPROTO(struct rq *rq, struct task_struct *p),
-+ TPARGS(rq, p));
-+DEFINE_TRACE(sched_wakeup,
-+ TPPROTO(struct rq *rq, struct task_struct *p),
-+ TPARGS(rq, p));
-+DEFINE_TRACE(sched_wakeup_new,
-+ TPPROTO(struct rq *rq, struct task_struct *p),
-+ TPARGS(rq, p));
-+DEFINE_TRACE(sched_switch,
-+ TPPROTO(struct rq *rq, struct task_struct *prev,
-+ struct task_struct *next),
-+ TPARGS(rq, prev, next));
-+DEFINE_TRACE(sched_migrate_task,
-+ TPPROTO(struct rq *rq, struct task_struct *p, int dest_cpu),
-+ TPARGS(rq, p, dest_cpu));
-+DEFINE_TRACE(sched_process_free,
-+ TPPROTO(struct task_struct *p),
-+ TPARGS(p));
-+DEFINE_TRACE(sched_process_exit,
-+ TPPROTO(struct task_struct *p),
-+ TPARGS(p));
-+DEFINE_TRACE(sched_process_wait,
-+ TPPROTO(struct pid *pid),
-+ TPARGS(pid));
-+DEFINE_TRACE(sched_process_fork,
-+ TPPROTO(struct task_struct *parent, struct task_struct *child),
-+ TPARGS(parent, child));
-+DEFINE_TRACE(sched_signal_send,
-+ TPPROTO(int sig, struct task_struct *p),
-+ TPARGS(sig, p));
-+
-+#endif
---- a/kernel/exit.c
-+++ b/kernel/exit.c
-@@ -50,6 +50,7 @@
- #include <linux/blkdev.h>
- #include <linux/task_io_accounting_ops.h>
- #include <linux/tracehook.h>
-+#include <trace/sched.h>
-
- #include <asm/uaccess.h>
- #include <asm/unistd.h>
-@@ -152,7 +153,10 @@ static void __exit_signal(struct task_st
-
- static void delayed_put_task_struct(struct rcu_head *rhp)
- {
-- put_task_struct(container_of(rhp, struct task_struct, rcu));
-+ struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
-+
-+ trace_sched_process_free(tsk);
-+ put_task_struct(tsk);
- }
-
-
-@@ -1076,6 +1080,8 @@ NORET_TYPE void do_exit(long code)
-
- if (group_dead)
- acct_process();
-+ trace_sched_process_exit(tsk);
-+
- exit_sem(tsk);
- exit_files(tsk);
- exit_fs(tsk);
-@@ -1679,6 +1685,8 @@ static long do_wait(enum pid_type type,
- struct task_struct *tsk;
- int retval;
-
-+ trace_sched_process_wait(pid);
-+
- add_wait_queue(¤t->signal->wait_chldexit,&wait);
- repeat:
- /*
---- a/kernel/fork.c
-+++ b/kernel/fork.c
-@@ -58,6 +58,7 @@
- #include <linux/tty.h>
- #include <linux/proc_fs.h>
- #include <linux/blkdev.h>
-+#include <trace/sched.h>
-
- #include <asm/pgtable.h>
- #include <asm/pgalloc.h>
-@@ -1363,6 +1364,8 @@ long do_fork(unsigned long clone_flags,
- if (!IS_ERR(p)) {
- struct completion vfork;
-
-+ trace_sched_process_fork(current, p);
-+
- nr = task_pid_vnr(p);
-
- if (clone_flags & CLONE_PARENT_SETTID)
---- a/kernel/kthread.c
-+++ b/kernel/kthread.c
-@@ -13,6 +13,7 @@
- #include <linux/file.h>
- #include <linux/module.h>
- #include <linux/mutex.h>
-+#include <trace/sched.h>
-
- #define KTHREAD_NICE_LEVEL (-5)
-
-@@ -206,6 +207,8 @@ int kthread_stop(struct task_struct *k)
- /* It could exit after stop_info.k set, but before wake_up_process. */
- get_task_struct(k);
-
-+ trace_sched_kthread_stop(k);
-+
- /* Must init completion *before* thread sees kthread_stop_info.k */
- init_completion(&kthread_stop_info.done);
- smp_wmb();
-@@ -221,6 +224,8 @@ int kthread_stop(struct task_struct *k)
- ret = kthread_stop_info.err;
- mutex_unlock(&kthread_stop_lock);
-
-+ trace_sched_kthread_stop_ret(ret);
-+
- return ret;
- }
- EXPORT_SYMBOL(kthread_stop);
---- a/kernel/sched.c
-+++ b/kernel/sched.c
-@@ -71,6 +71,7 @@
- #include <linux/debugfs.h>
- #include <linux/ctype.h>
- #include <linux/ftrace.h>
-+#include <trace/sched.h>
- #include <linux/perfmon_kern.h>
-
- #include <asm/tlb.h>
-@@ -1914,6 +1915,7 @@ unsigned long wait_task_inactive(struct
- * just go back and repeat.
- */
- rq = task_rq_lock(p, &flags);
-+ trace_sched_wait_task(rq, p);
- running = task_running(rq, p);
- on_rq = p->se.on_rq;
- ncsw = 0;
-@@ -2306,9 +2308,7 @@ out_activate:
- success = 1;
-
- out_running:
-- trace_mark(kernel_sched_wakeup,
-- "pid %d state %ld ## rq %p task %p rq->curr %p",
-- p->pid, p->state, rq, p, rq->curr);
-+ trace_sched_wakeup(rq, p);
- check_preempt_curr(rq, p);
-
- p->state = TASK_RUNNING;
-@@ -2441,9 +2441,7 @@ void wake_up_new_task(struct task_struct
- p->sched_class->task_new(rq, p);
- inc_nr_running(rq);
- }
-- trace_mark(kernel_sched_wakeup_new,
-- "pid %d state %ld ## rq %p task %p rq->curr %p",
-- p->pid, p->state, rq, p, rq->curr);
-+ trace_sched_wakeup_new(rq, p);
- check_preempt_curr(rq, p);
- #ifdef CONFIG_SMP
- if (p->sched_class->task_wake_up)
-@@ -2616,11 +2614,7 @@ context_switch(struct rq *rq, struct tas
- struct mm_struct *mm, *oldmm;
-
- prepare_task_switch(rq, prev, next);
-- trace_mark(kernel_sched_schedule,
-- "prev_pid %d next_pid %d prev_state %ld "
-- "## rq %p prev %p next %p",
-- prev->pid, next->pid, prev->state,
-- rq, prev, next);
-+ trace_sched_switch(rq, prev, next);
- mm = next->mm;
- oldmm = prev->active_mm;
- /*
-@@ -2860,6 +2854,7 @@ static void sched_migrate_task(struct ta
- || unlikely(!cpu_active(dest_cpu)))
- goto out;
-
-+ trace_sched_migrate_task(rq, p, dest_cpu);
- /* force the process onto the specified CPU */
- if (migrate_task(p, dest_cpu, &req)) {
- /* Need to wait for migration thread (might exit: take ref). */
---- a/kernel/signal.c
-+++ b/kernel/signal.c
-@@ -27,6 +27,7 @@
- #include <linux/freezer.h>
- #include <linux/pid_namespace.h>
- #include <linux/nsproxy.h>
-+#include <trace/sched.h>
-
- #include <asm/param.h>
- #include <asm/uaccess.h>
-@@ -803,6 +804,8 @@ static int send_signal(int sig, struct s
- struct sigpending *pending;
- struct sigqueue *q;
-
-+ trace_sched_signal_send(sig, t);
-+
- assert_spin_locked(&t->sighand->siglock);
- if (!prepare_signal(sig, t))
- return 0;
projects / people / pmueller / ipfire-2.x.git / blobdiff