From 43d2b113241d6797b890318767e0af78e313414b Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Tue, 10 Jan 2012 15:08:09 -0800 Subject: tracepoint: add tracepoints for debugging oom_score_adj oom_score_adj is used for guarding processes from OOM-Killer. One of problem is that it's inherited at fork(). When a daemon set oom_score_adj and make children, it's hard to know where the value is set. This patch adds some tracepoints useful for debugging. This patch adds 3 trace points. - creating new task - renaming a task (exec) - set oom_score_adj To debug, users need to enable some trace pointer. Maybe filtering is useful as # EVENT=/sys/kernel/debug/tracing/events/task/ # echo "oom_score_adj != 0" > $EVENT/task_newtask/filter # echo "oom_score_adj != 0" > $EVENT/task_rename/filter # echo 1 > $EVENT/enable # EVENT=/sys/kernel/debug/tracing/events/oom/ # echo 1 > $EVENT/enable output will be like this. # grep oom /sys/kernel/debug/tracing/trace bash-7699 [007] d..3 5140.744510: oom_score_adj_update: pid=7699 comm=bash oom_score_adj=-1000 bash-7699 [007] ...1 5151.818022: task_newtask: pid=7729 comm=bash clone_flags=1200011 oom_score_adj=-1000 ls-7729 [003] ...2 5151.818504: task_rename: pid=7729 oldcomm=bash newcomm=ls oom_score_adj=-1000 bash-7699 [002] ...1 5175.701468: task_newtask: pid=7730 comm=bash clone_flags=1200011 oom_score_adj=-1000 grep-7730 [007] ...2 5175.701993: task_rename: pid=7730 oldcomm=bash newcomm=grep oom_score_adj=-1000 Signed-off-by: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/oom_kill.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'mm/oom_kill.c') diff --git a/mm/oom_kill.c b/mm/oom_kill.c index eeb27e27dce3..7c122faa05c5 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -33,6 +33,10 @@ #include #include #include +#include + +#define CREATE_TRACE_POINTS +#include int sysctl_panic_on_oom; int sysctl_oom_kill_allocating_task; @@ -55,6 +59,7 @@ void compare_swap_oom_score_adj(int old_val, int new_val) spin_lock_irq(&sighand->siglock); if (current->signal->oom_score_adj == old_val) current->signal->oom_score_adj = new_val; + trace_oom_score_adj_update(current); spin_unlock_irq(&sighand->siglock); } @@ -74,6 +79,7 @@ int test_set_oom_score_adj(int new_val) spin_lock_irq(&sighand->siglock); old_val = current->signal->oom_score_adj; current->signal->oom_score_adj = new_val; + trace_oom_score_adj_update(current); spin_unlock_irq(&sighand->siglock); return old_val; -- cgit v1.2.3