Re: [PATCH 2/2] cpuset,mm: fix no node to alloc memory when changing cpuset's mems

[Miao Xie <miaox@cn.fujitsu.com>]

on 2010-5-12 9:49, Andrew Morton wrote:
...
>> --- a/kernel/exit.c
>> +++ b/kernel/exit.c
>> @@ -16,6 +16,7 @@
>>  #include <linux/key.h>
>>  #include <linux/security.h>
>>  #include <linux/cpu.h>
>> +#include <linux/cpuset.h>
>>  #include <linux/acct.h>
>>  #include <linux/tsacct_kern.h>
>>  #include <linux/file.h>
>> @@ -1003,8 +1004,10 @@ NORET_TYPE void do_exit(long code)
>>  
>>  	exit_notify(tsk, group_dead);
>>  #ifdef CONFIG_NUMA
>> +	task_lock(tsk);
>>  	mpol_put(tsk->mempolicy);
>>  	tsk->mempolicy = NULL;
>> +	task_unlock(tsk);
>>  #endif
>>  #ifdef CONFIG_FUTEX
>>  	if (unlikely(current->pi_state_cache))
> 
> Given that this function is already holding task_lock(tsk), this
> didn't work very well.

Sorry for replying late.

Thanks for your patch that removes task_lock(tsk).

I made this patch against the mainline tree, and do_exit() in the mainline tree
doesn't hold task_lock(tsk), so I took task_lock(tsk). But I didn't take notice
that do_exit() in the mmotm tree had been changed, and I made this mistake.

> Also, why was the inclusion of cpuset.h added?  Nothing which this
> patch adds appears to need it?
> 

This is my mistake, I will make patch to cleanup it.

Thanks!
Miao