[patch] mm, oom: do not schedule if current has been killed

[patch] mm, oom: do not schedule if current has been killed

[David Rientjes]

The oom killer currently schedules away from current in an
uninterruptible sleep if it does not have access to memory reserves.
It's possible that current was killed because it shares memory with the
oom killed thread or because it was killed by the user in the interim,
however.

This patch only schedules away from current if it does not have a pending
kill, i.e. if it does not share memory with the oom killed thread.  It's
possible that it will immediately retry its memory allocation and fail,
but it will immediately be given access to memory reserves if it calls
the oom killer again.

This prevents the delay of memory freeing when threads that share memory
with the oom killed thread get unnecessarily scheduled.

Signed-off-by: David Rientjes <rientjes@google.com>
---
 mm/oom_kill.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -749,7 +749,7 @@ out:
 	 * Give "p" a good chance of killing itself before we
 	 * retry to allocate memory unless "p" is current
 	 */
-	if (killed && !test_thread_flag(TIF_MEMDIE))
+	if (killed && !fatal_signal_pending(current))
 		schedule_timeout_uninterruptible(1);
 }
 
@@ -765,6 +765,6 @@ void pagefault_out_of_memory(void)
 		out_of_memory(NULL, 0, 0, NULL, false);
 		clear_system_oom();
 	}
-	if (!test_thread_flag(TIF_MEMDIE))
+	if (!fatal_signal_pending(current))
 		schedule_timeout_uninterruptible(1);
 }

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Re: [patch] mm, oom: do not schedule if current has been killed

[Kamezawa Hiroyuki]

(2012/06/19 10:08), David Rientjes wrote:
> The oom killer currently schedules away from current in an
> uninterruptible sleep if it does not have access to memory reserves.
> It's possible that current was killed because it shares memory with the
> oom killed thread or because it was killed by the user in the interim,
> however.
>
> This patch only schedules away from current if it does not have a pending
> kill, i.e. if it does not share memory with the oom killed thread.  It's
> possible that it will immediately retry its memory allocation and fail,
> but it will immediately be given access to memory reserves if it calls
> the oom killer again.
>
> This prevents the delay of memory freeing when threads that share memory
> with the oom killed thread get unnecessarily scheduled.
>
> Signed-off-by: David Rientjes<rientjes@google.com>

fatal_signal_pending() == false if test_thread_flag(TIF_MEMDIE)==false ?

I'll check memcg code..

Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>



> ---
>   mm/oom_kill.c |    4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -749,7 +749,7 @@ out:
>   	 * Give "p" a good chance of killing itself before we
>   	 * retry to allocate memory unless "p" is current
>   	 */
> -	if (killed&&  !test_thread_flag(TIF_MEMDIE))
> +	if (killed&&  !fatal_signal_pending(current))
>   		schedule_timeout_uninterruptible(1);
>   }
>
> @@ -765,6 +765,6 @@ void pagefault_out_of_memory(void)
>   		out_of_memory(NULL, 0, 0, NULL, false);
>   		clear_system_oom();
>   	}
> -	if (!test_thread_flag(TIF_MEMDIE))
> +	if (!fatal_signal_pending(current))
>   		schedule_timeout_uninterruptible(1);
>   }


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Re: [patch] mm, oom: do not schedule if current has been killed

[David Rientjes]

On Tue, 19 Jun 2012, Kamezawa Hiroyuki wrote:

> fatal_signal_pending() == false if test_thread_flag(TIF_MEMDIE)==false ?
> 

Yeah, the only thing that sets TIF_MEMDIE is the oom killer and it 
immediately SIGKILLs it afterwards.

Aside: I've been thinking of adding a check to the page allocator for 
!(gfp & __GFP_FS) && !(gfp & __GFP_NORETRY) to set TIF_MEMDIE for current 
if it has a fatal signal since such an allocation isn't eligible for 
calling into the oom killer.

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[patch v2] mm, oom: do not schedule if current has been killed

[David Rientjes]

The oom killer currently schedules away from current in an
uninterruptible sleep if it does not have access to memory reserves.
It's possible that current was killed because it shares memory with the
oom killed thread or because it was killed by the user in the interim,
however.

This patch only schedules away from current if it does not have a pending
kill, i.e. if it does not share memory with the oom killed thread, or is
already exiting.  It's possible that it will immediately retry its memory
allocation and fail, but it will immediately be given access to memory
reserves if it calls the oom killer again.

This prevents the delay of memory freeing when threads that share memory
with the oom killed thread get unnecessarily scheduled.

Signed-off-by: David Rientjes <rientjes@google.com>
---
 mm/oom_kill.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -746,10 +746,11 @@ out:
 	read_unlock(&tasklist_lock);
 
 	/*
-	 * Give "p" a good chance of killing itself before we
+	 * Give "p" a good chance of exiting before we
 	 * retry to allocate memory unless "p" is current
 	 */
-	if (killed && !test_thread_flag(TIF_MEMDIE))
+	if (killed && !fatal_signal_pending(current) &&
+		      !(current->flags & PF_EXITING))
 		schedule_timeout_uninterruptible(1);
 }
 
@@ -765,6 +766,6 @@ void pagefault_out_of_memory(void)
 		out_of_memory(NULL, 0, 0, NULL, false);
 		clear_system_oom();
 	}
-	if (!test_thread_flag(TIF_MEMDIE))
+	if (!fatal_signal_pending(current) && !(current->flags & PF_EXITING))
 		schedule_timeout_uninterruptible(1);
 }

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Re: [patch v2] mm, oom: do not schedule if current has been killed

[Kamezawa Hiroyuki]

(2012/06/19 11:31), David Rientjes wrote:
> The oom killer currently schedules away from current in an
> uninterruptible sleep if it does not have access to memory reserves.
> It's possible that current was killed because it shares memory with the
> oom killed thread or because it was killed by the user in the interim,
> however.
>
> This patch only schedules away from current if it does not have a pending
> kill, i.e. if it does not share memory with the oom killed thread, or is
> already exiting.  It's possible that it will immediately retry its memory
> allocation and fail, but it will immediately be given access to memory
> reserves if it calls the oom killer again.
>
> This prevents the delay of memory freeing when threads that share memory
> with the oom killed thread get unnecessarily scheduled.
>
> Signed-off-by: David Rientjes<rientjes@google.com>

seems good to me.
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>


> ---
>   mm/oom_kill.c |    7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -746,10 +746,11 @@ out:
>   	read_unlock(&tasklist_lock);
>
>   	/*
> -	 * Give "p" a good chance of killing itself before we
> +	 * Give "p" a good chance of exiting before we
>   	 * retry to allocate memory unless "p" is current
>   	 */
> -	if (killed&&  !test_thread_flag(TIF_MEMDIE))
> +	if (killed&&  !fatal_signal_pending(current)&&
> +		      !(current->flags&  PF_EXITING))
>   		schedule_timeout_uninterruptible(1);
>   }
>
> @@ -765,6 +766,6 @@ void pagefault_out_of_memory(void)
>   		out_of_memory(NULL, 0, 0, NULL, false);
>   		clear_system_oom();
>   	}
> -	if (!test_thread_flag(TIF_MEMDIE))
> +	if (!fatal_signal_pending(current)&&  !(current->flags&  PF_EXITING))
>   		schedule_timeout_uninterruptible(1);
>   }


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Re: [patch v2] mm, oom: do not schedule if current has been killed

[KOSAKI Motohiro]

On Mon, Jun 18, 2012 at 10:31 PM, David Rientjes <rientjes@google.com> wrote:
> The oom killer currently schedules away from current in an
> uninterruptible sleep if it does not have access to memory reserves.
> It's possible that current was killed because it shares memory with the
> oom killed thread or because it was killed by the user in the interim,
> however.
>
> This patch only schedules away from current if it does not have a pending
> kill, i.e. if it does not share memory with the oom killed thread, or is
> already exiting.  It's possible that it will immediately retry its memory
> allocation and fail, but it will immediately be given access to memory
> reserves if it calls the oom killer again.
>
> This prevents the delay of memory freeing when threads that share memory
> with the oom killed thread get unnecessarily scheduled.
>
> Signed-off-by: David Rientjes <rientjes@google.com>
> ---
>  mm/oom_kill.c |    7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -746,10 +746,11 @@ out:
>        read_unlock(&tasklist_lock);
>
>        /*
> -        * Give "p" a good chance of killing itself before we
> +        * Give "p" a good chance of exiting before we
>         * retry to allocate memory unless "p" is current
>         */
> -       if (killed && !test_thread_flag(TIF_MEMDIE))
> +       if (killed && !fatal_signal_pending(current) &&
> +                     !(current->flags & PF_EXITING))
>                schedule_timeout_uninterruptible(1);
>  }

Why don't check gfp_flags? I think the rule is,

1) a thread of newly marked as TIF_MEMDIE
    -> now it has a capability to access reseve memory. let's immediately retry.
2) allocation for GFP_HIGHUSER_MOVABLE
    -> we can fail to allocate it safely. let's immediately fail.
        (I suspect we need to change page allocator too)
3) GFP_KERNEL and PF_EXITING
    -> don't retry immediately. It shall fail again. let's wait until
killed process
        is exited.



> @@ -765,6 +766,6 @@ void pagefault_out_of_memory(void)
>                out_of_memory(NULL, 0, 0, NULL, false);
>                clear_system_oom();
>        }
> -       if (!test_thread_flag(TIF_MEMDIE))
> +       if (!fatal_signal_pending(current) && !(current->flags & PF_EXITING))
>                schedule_timeout_uninterruptible(1);

This makes sense to me.

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Re: [patch v2] mm, oom: do not schedule if current has been killed

[David Rientjes]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 1847 bytes --]

On Tue, 19 Jun 2012, KOSAKI Motohiro wrote:

> > diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> > --- a/mm/oom_kill.c
> > +++ b/mm/oom_kill.c
> > @@ -746,10 +746,11 @@ out:
> >        read_unlock(&tasklist_lock);
> >
> >        /*
> > -        * Give "p" a good chance of killing itself before we
> > +        * Give "p" a good chance of exiting before we
> >         * retry to allocate memory unless "p" is current
> >         */
> > -       if (killed && !test_thread_flag(TIF_MEMDIE))
> > +       if (killed && !fatal_signal_pending(current) &&
> > +                     !(current->flags & PF_EXITING))
> >                schedule_timeout_uninterruptible(1);
> >  }
> 
> Why don't check gfp_flags? I think the rule is,
> 
> 1) a thread of newly marked as TIF_MEMDIE
>     -> now it has a capability to access reseve memory. let's immediately retry.
> 2) allocation for GFP_HIGHUSER_MOVABLE
>     -> we can fail to allocate it safely. let's immediately fail.
>         (I suspect we need to change page allocator too)
> 3) GFP_KERNEL and PF_EXITING
>     -> don't retry immediately. It shall fail again. let's wait until
> killed process
>         is exited.
> 

The killed process may exit but it does not guarantee that its memory will 
be freed if it's shared with current.  This is the case that the patch is 
addressing, where right now we unnecessarily schedule if current has been 
killed or is already along the exit path.  We want to retry as soon as 
possible so that either the allocation now succeeds or we can recall the 
oom killer as soon as possible and get TIF_MEMDIE set because we have a 
fatal signal so current may exit in a timely way as well.  The point is 
that if current has either a SIGKILL or is already exiting as it returns 
from the oom killer, it does no good to continue to stall and prevent that 
memory freeing.

Re: [patch v2] mm, oom: do not schedule if current has been killed

[Oleg Nesterov]

On 06/18, David Rientjes wrote:
>
> This patch only schedules away from current if it does not have a pending
> kill,

Can't really comment this patch, just one note...

> -	if (killed && !test_thread_flag(TIF_MEMDIE))
> +	if (killed && !fatal_signal_pending(current) &&
> +		      !(current->flags & PF_EXITING))
>  		schedule_timeout_uninterruptible(1);

Perhaps

	if (killed && !(current->flags & PF_EXITING))
		schedule_timeout_killable(1);

makes more sense?

If fatal_signal_pending() == T then schedule_timeout_killable()
is nop, but unline uninterruptible_ it can be SIGKILL'ed.

But if you prefer to check fatal_signal_pending() I won't argue.

Oleg.

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Re: [patch v2] mm, oom: do not schedule if current has been killed

[KOSAKI Motohiro]

On 6/19/2012 2:26 AM, David Rientjes wrote:
> On Tue, 19 Jun 2012, KOSAKI Motohiro wrote:
> 
>>> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
>>> --- a/mm/oom_kill.c
>>> +++ b/mm/oom_kill.c
>>> @@ -746,10 +746,11 @@ out:
>>>        read_unlock(&tasklist_lock);
>>>
>>>        /*
>>> -        * Give "p" a good chance of killing itself before we
>>> +        * Give "p" a good chance of exiting before we
>>>         * retry to allocate memory unless "p" is current
>>>         */
>>> -       if (killed && !test_thread_flag(TIF_MEMDIE))
>>> +       if (killed && !fatal_signal_pending(current) &&
>>> +                     !(current->flags & PF_EXITING))
>>>                schedule_timeout_uninterruptible(1);
>>>  }
>>
>> Why don't check gfp_flags? I think the rule is,
>>
>> 1) a thread of newly marked as TIF_MEMDIE
>>     -> now it has a capability to access reseve memory. let's immediately retry.
>> 2) allocation for GFP_HIGHUSER_MOVABLE
>>     -> we can fail to allocate it safely. let's immediately fail.
>>         (I suspect we need to change page allocator too)
>> 3) GFP_KERNEL and PF_EXITING
>>     -> don't retry immediately. It shall fail again. let's wait until
>> killed process
>>         is exited.
>>
> 
> The killed process may exit but it does not guarantee that its memory will 
> be freed if it's shared with current.  This is the case that the patch is 
> addressing, where right now we unnecessarily schedule if current has been 
> killed or is already along the exit path.  We want to retry as soon as 
> possible so that either the allocation now succeeds or we can recall the 
> oom killer as soon as possible and get TIF_MEMDIE set because we have a 
> fatal signal so current may exit in a timely way as well.  The point is 
> that if current has either a SIGKILL or is already exiting as it returns 
> from the oom killer, it does no good to continue to stall and prevent that 
> memory freeing.

You missed live lock risk. immediate retry makes immediate fail if no one
freed any memory. Even if the task call out_of_memory() again, select_bad_process()
may return -1 and don't makes any forward progress.



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Re: [patch v2] mm, oom: do not schedule if current has been killed

[David Rientjes]

On Tue, 19 Jun 2012, KOSAKI Motohiro wrote:

> > The killed process may exit but it does not guarantee that its memory will 
> > be freed if it's shared with current.  This is the case that the patch is 
> > addressing, where right now we unnecessarily schedule if current has been 
> > killed or is already along the exit path.  We want to retry as soon as 
> > possible so that either the allocation now succeeds or we can recall the 
> > oom killer as soon as possible and get TIF_MEMDIE set because we have a 
> > fatal signal so current may exit in a timely way as well.  The point is 
> > that if current has either a SIGKILL or is already exiting as it returns 
> > from the oom killer, it does no good to continue to stall and prevent that 
> > memory freeing.
> 
> You missed live lock risk. immediate retry makes immediate fail if no one
> freed any memory. Even if the task call out_of_memory() again, select_bad_process()
> may return -1 and don't makes any forward progress.
> 

I missed a livelock?  You missed the fact that the oom killer is 
short-circuited by this before anything else gets done:

	if (fatal_signal_pending(current)) {
		set_thread_flag(TIF_MEMDIE);
		return;
	}

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Re: [patch v2] mm, oom: do not schedule if current has been killed

[KOSAKI Motohiro]

On 6/19/2012 2:59 PM, David Rientjes wrote:
> On Tue, 19 Jun 2012, KOSAKI Motohiro wrote:
> 
>>> The killed process may exit but it does not guarantee that its memory will 
>>> be freed if it's shared with current.  This is the case that the patch is 
>>> addressing, where right now we unnecessarily schedule if current has been 
>>> killed or is already along the exit path.  We want to retry as soon as 
>>> possible so that either the allocation now succeeds or we can recall the 
>>> oom killer as soon as possible and get TIF_MEMDIE set because we have a 
>>> fatal signal so current may exit in a timely way as well.  The point is 
>>> that if current has either a SIGKILL or is already exiting as it returns 
>>> from the oom killer, it does no good to continue to stall and prevent that 
>>> memory freeing.
>>
>> You missed live lock risk. immediate retry makes immediate fail if no one
>> freed any memory. Even if the task call out_of_memory() again, select_bad_process()
>> may return -1 and don't makes any forward progress.
>>
> 
> I missed a livelock?  You missed the fact that the oom killer is 
> short-circuited by this before anything else gets done:
> 
> 	if (fatal_signal_pending(current)) {
> 		set_thread_flag(TIF_MEMDIE);
> 		return;
> 	}
> 

I talked about PF_EXITING. fatal signal is no problem.


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Re: [patch v2] mm, oom: do not schedule if current has been killed

[David Rientjes]

On Tue, 19 Jun 2012, Oleg Nesterov wrote:

> 	if (killed && !(current->flags & PF_EXITING))
> 		schedule_timeout_killable(1);
> 
> makes more sense?
> 
> If fatal_signal_pending() == T then schedule_timeout_killable()
> is nop, but unline uninterruptible_ it can be SIGKILL'ed.
> 

Ok, that's certainly cleaner.  I'll post a v3, thanks for the suggestion.

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[patch v3] mm, oom: do not schedule if current has been killed

[David Rientjes]

The oom killer currently schedules away from current in an
uninterruptible sleep if it does not have access to memory reserves.
It's possible that current was killed because it shares memory with the
oom killed thread or because it was killed by the user in the interim,
however.

This patch only schedules away from current if it does not have a pending
kill, i.e. if it does not share memory with the oom killed thread.  It's
possible that it will immediately retry its memory allocation and fail,
but it will immediately be given access to memory reserves if it calls
the oom killer again.

This prevents the delay of memory freeing when threads that share memory
with the oom killed thread get unnecessarily scheduled.

Signed-off-by: David Rientjes <rientjes@google.com>
---
 mm/oom_kill.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -746,11 +746,11 @@ out:
 	read_unlock(&tasklist_lock);
 
 	/*
-	 * Give "p" a good chance of killing itself before we
-	 * retry to allocate memory unless "p" is current
+	 * Give the killed threads a good chance of exiting before trying to
+	 * allocate memory again.
 	 */
-	if (killed && !test_thread_flag(TIF_MEMDIE))
-		schedule_timeout_uninterruptible(1);
+	if (killed)
+		schedule_timeout_killable(1);
 }
 
 /*
@@ -765,6 +765,5 @@ void pagefault_out_of_memory(void)
 		out_of_memory(NULL, 0, 0, NULL, false);
 		clear_system_oom();
 	}
-	if (!test_thread_flag(TIF_MEMDIE))
-		schedule_timeout_uninterruptible(1);
+	schedule_timeout_killable(1);
 }

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Re: [patch v3] mm, oom: do not schedule if current has been killed

[KOSAKI Motohiro]

(6/19/12 4:58 PM), David Rientjes wrote:
> The oom killer currently schedules away from current in an
> uninterruptible sleep if it does not have access to memory reserves.
> It's possible that current was killed because it shares memory with the
> oom killed thread or because it was killed by the user in the interim,
> however.
> 
> This patch only schedules away from current if it does not have a pending
> kill, i.e. if it does not share memory with the oom killed thread.  It's
> possible that it will immediately retry its memory allocation and fail,
> but it will immediately be given access to memory reserves if it calls
> the oom killer again.
> 
> This prevents the delay of memory freeing when threads that share memory
> with the oom killed thread get unnecessarily scheduled.
> 
> Signed-off-by: David Rientjes <rientjes@google.com>
> ---
>  mm/oom_kill.c |   11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -746,11 +746,11 @@ out:
>  	read_unlock(&tasklist_lock);
>  
>  	/*
> -	 * Give "p" a good chance of killing itself before we
> -	 * retry to allocate memory unless "p" is current
> +	 * Give the killed threads a good chance of exiting before trying to
> +	 * allocate memory again.
>  	 */
> -	if (killed && !test_thread_flag(TIF_MEMDIE))
> -		schedule_timeout_uninterruptible(1);
> +	if (killed)
> +		schedule_timeout_killable(1);
>  }

This is not match I expected. but I have no seen a big problem.

Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>


>  
>  /*
> @@ -765,6 +765,5 @@ void pagefault_out_of_memory(void)
>  		out_of_memory(NULL, 0, 0, NULL, false);
>  		clear_system_oom();
>  	}
> -	if (!test_thread_flag(TIF_MEMDIE))
> -		schedule_timeout_uninterruptible(1);
> +	schedule_timeout_killable(1);
>  }
> 
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Re: [patch v3] mm, oom: do not schedule if current has been killed

[Kamezawa Hiroyuki]

(2012/06/20 6:39), KOSAKI Motohiro wrote:
> (6/19/12 4:58 PM), David Rientjes wrote:
>> The oom killer currently schedules away from current in an
>> uninterruptible sleep if it does not have access to memory reserves.
>> It's possible that current was killed because it shares memory with the
>> oom killed thread or because it was killed by the user in the interim,
>> however.
>>
>> This patch only schedules away from current if it does not have a pending
>> kill, i.e. if it does not share memory with the oom killed thread.  It's
>> possible that it will immediately retry its memory allocation and fail,
>> but it will immediately be given access to memory reserves if it calls
>> the oom killer again.
>>
>> This prevents the delay of memory freeing when threads that share memory
>> with the oom killed thread get unnecessarily scheduled.
>>
>> Signed-off-by: David Rientjes<rientjes@google.com>
>> ---
>>   mm/oom_kill.c |   11 +++++------
>>   1 file changed, 5 insertions(+), 6 deletions(-)
>>
>> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
>> --- a/mm/oom_kill.c
>> +++ b/mm/oom_kill.c
>> @@ -746,11 +746,11 @@ out:
>>   	read_unlock(&tasklist_lock);
>>
>>   	/*
>> -	 * Give "p" a good chance of killing itself before we
>> -	 * retry to allocate memory unless "p" is current
>> +	 * Give the killed threads a good chance of exiting before trying to
>> +	 * allocate memory again.
>>   	 */
>> -	if (killed&&  !test_thread_flag(TIF_MEMDIE))
>> -		schedule_timeout_uninterruptible(1);
>> +	if (killed)
>> +		schedule_timeout_killable(1);
>>   }
>
> This is not match I expected. but I have no seen a big problem.
>
> Acked-by: KOSAKI Motohiro<kosaki.motohiro@jp.fujitsu.com>
>

Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

I'll check memcg part to make it consistent to this when this goes to -mm.




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Re: [patch v3] mm, oom: do not schedule if current has been killed

[David Rientjes]

On Wed, 20 Jun 2012, Kamezawa Hiroyuki wrote:

> I'll check memcg part to make it consistent to this when this goes to -mm.
> 

It's merged.

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