From 43d2b113241d6797b890318767e0af78e313414b Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Tue, 10 Jan 2012 15:08:09 -0800 Subject: [PATCH] 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 --- fs/exec.c | 4 +++ fs/proc/base.c | 3 ++ include/trace/events/oom.h | 33 ++++++++++++++++++++ include/trace/events/task.h | 61 +++++++++++++++++++++++++++++++++++++ kernel/fork.c | 6 ++++ mm/oom_kill.c | 6 ++++ 6 files changed, 113 insertions(+) create mode 100644 include/trace/events/oom.h create mode 100644 include/trace/events/task.h diff --git a/fs/exec.c b/fs/exec.c index 3f64b9f26e7d..aeb135c7ff5c 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -59,6 +59,8 @@ #include #include #include + +#include #include "internal.h" int core_uses_pid; @@ -1054,6 +1056,8 @@ void set_task_comm(struct task_struct *tsk, char *buf) { task_lock(tsk); + trace_task_rename(tsk, buf); + /* * Threads may access current->comm without holding * the task lock, so write the string carefully. diff --git a/fs/proc/base.c b/fs/proc/base.c index a1dddda999f2..1aab5fe05a1b 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -86,6 +86,7 @@ #ifdef CONFIG_HARDWALL #include #endif +#include #include "internal.h" /* NOTE: @@ -1010,6 +1011,7 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf, else task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; + trace_oom_score_adj_update(task); err_sighand: unlock_task_sighand(task, &flags); err_task_lock: @@ -1097,6 +1099,7 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, task->signal->oom_score_adj = oom_score_adj; if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) task->signal->oom_score_adj_min = oom_score_adj; + trace_oom_score_adj_update(task); /* * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is * always attainable. diff --git a/include/trace/events/oom.h b/include/trace/events/oom.h new file mode 100644 index 000000000000..dd4ba3b92002 --- /dev/null +++ b/include/trace/events/oom.h @@ -0,0 +1,33 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM oom + +#if !defined(_TRACE_OOM_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_OOM_H +#include + +TRACE_EVENT(oom_score_adj_update, + + TP_PROTO(struct task_struct *task), + + TP_ARGS(task), + + TP_STRUCT__entry( + __field( pid_t, pid) + __array( char, comm, TASK_COMM_LEN ) + __field( int, oom_score_adj) + ), + + TP_fast_assign( + __entry->pid = task->pid; + memcpy(__entry->comm, task->comm, TASK_COMM_LEN); + __entry->oom_score_adj = task->signal->oom_score_adj; + ), + + TP_printk("pid=%d comm=%s oom_score_adj=%d", + __entry->pid, __entry->comm, __entry->oom_score_adj) +); + +#endif + +/* This part must be outside protection */ +#include diff --git a/include/trace/events/task.h b/include/trace/events/task.h new file mode 100644 index 000000000000..b53add02e929 --- /dev/null +++ b/include/trace/events/task.h @@ -0,0 +1,61 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM task + +#if !defined(_TRACE_TASK_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_TASK_H +#include + +TRACE_EVENT(task_newtask, + + TP_PROTO(struct task_struct *task, unsigned long clone_flags), + + TP_ARGS(task, clone_flags), + + TP_STRUCT__entry( + __field( pid_t, pid) + __array( char, comm, TASK_COMM_LEN) + __field( unsigned long, clone_flags) + __field( int, oom_score_adj) + ), + + TP_fast_assign( + __entry->pid = task->pid; + memcpy(__entry->comm, task->comm, TASK_COMM_LEN); + __entry->clone_flags = clone_flags; + __entry->oom_score_adj = task->signal->oom_score_adj; + ), + + TP_printk("pid=%d comm=%s clone_flags=%lx oom_score_adj=%d", + __entry->pid, __entry->comm, + __entry->clone_flags, __entry->oom_score_adj) +); + +TRACE_EVENT(task_rename, + + TP_PROTO(struct task_struct *task, char *comm), + + TP_ARGS(task, comm), + + TP_STRUCT__entry( + __field( pid_t, pid) + __array( char, oldcomm, TASK_COMM_LEN) + __array( char, newcomm, TASK_COMM_LEN) + __field( int, oom_score_adj) + ), + + TP_fast_assign( + __entry->pid = task->pid; + memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN); + memcpy(entry->newcomm, comm, TASK_COMM_LEN); + __entry->oom_score_adj = task->signal->oom_score_adj; + ), + + TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%d", + __entry->pid, __entry->oldcomm, + __entry->newcomm, __entry->oom_score_adj) +); + +#endif + +/* This part must be outside protection */ +#include diff --git a/kernel/fork.c b/kernel/fork.c index b00711ce7c13..5e1391b5ade0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -76,6 +76,9 @@ #include +#define CREATE_TRACE_POINTS +#include + /* * Protected counters by write_lock_irq(&tasklist_lock) */ @@ -1370,6 +1373,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (clone_flags & CLONE_THREAD) threadgroup_change_end(current); perf_event_fork(p); + + trace_task_newtask(p, clone_flags); + return p; bad_fork_free_pid: 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;