[Devel] Re: [ckrm-tech] [PATCH 5/13] BC: user interface (syscalls)

[Pavel Emelianov]

Balbir Singh wrote:
>> +
>> +asmlinkage long sys_set_bcid(bcid_t id)
>> +{
>> +    int error;
>> +    struct beancounter *bc;
>> +    struct task_beancounter *task_bc;
>> +
>> +    task_bc = &current->task_bc;
>
> I was playing around with the bc patches and found that to make
> use of bc's, I had to actually call set_bcid() and then exec() a
> task/shell so that the id would stick around. Would you consider
That sounds very strange as sys_set_bcid() actually changes current's
exec_bc.
One note is about mm's bc - mm obtains new bc only after fork or exec -
that's
true. But kmemsize starts charging right after the sys_set_bcid.
> changing sys_set_bcid to sys_set_task_bcid() or adding a new
> system call sys_set_task_bcid()? We could pass the pid that we
> intend to associate with the new id. This also means we'll need
> locking around to protect task->task_bc.