Re: [PATCH respin, was PATCH for review] During VM oom condition, kill all threads in process group

[Pavel Machek <pavel@ucw.cz>]

Hi!

> 
> During VM oom condition, kill all threads in process group.
> 
> We have had complaints where a threaded application is left in a bad
> state after one of it's threads is killed when we hit a VM: out_of_memory
> condition.
> Killing just one of the process threads can leave the application in a
> bad state, whereas killing the entire process group would allow for
> the application to restart, or be otherwise handled, and makes it very
> obvious that something has gone wrong.
> 
> This change allows the entire process group to be taken down, rather
> than just the one thread.
> 
> Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>

> diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c
> index 17123e9..13fdfa3 100644
> --- a/arch/sparc64/mm/fault.c
> +++ b/arch/sparc64/mm/fault.c
> @@ -466,7 +466,7 @@ out_of_memory:
>  	up_read(&mm->mmap_sem);
>  	printk("VM: killing process %s\n", current->comm);
>  	if (!(regs->tstate & TSTATE_PRIV))
> -		do_exit(SIGKILL);
> +		do_group_exit(SIGKILL);
>  	goto handle_kernel_fault;
>  
>  intr_or_no_mm:

is the printk still accurate (does it kill more than one process now)?
Why does it print when it will not really kill the process?

I see similar code across all the archs... would it make sense to
create common helper... or is the helper too trivial?
									Pavel
-- 
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