[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <483547B1.6030604@linux.vnet.ibm.com>
Date: Thu, 22 May 2008 15:45:13 +0530
From: Balbir Singh <balbir@...ux.vnet.ibm.com>
To: Andrew Morton <akpm@...ux-foundation.org>
CC: linux-mm@...ck.org, Sudhir Kumar <skumar@...ux.vnet.ibm.com>,
YAMAMOTO Takashi <yamamoto@...inux.co.jp>,
Paul Menage <menage@...gle.com>, lizf@...fujitsu.com,
linux-kernel@...r.kernel.org, Pavel Emelianov <xemul@...nvz.org>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Subject: Re: [-mm][PATCH 4/4] Add memrlimit controller accounting and control
(v5)
Andrew Morton wrote:
> On Wed, 21 May 2008 21:00:12 +0530 Balbir Singh <balbir@...ux.vnet.ibm.com> wrote:
>
>> This patch adds support for accounting and control of virtual address space
>> limits. The accounting is done via the rlimit_cgroup_(un)charge_as functions.
>> The core of the accounting takes place during fork time in copy_process(),
>> may_expand_vm(), remove_vma_list() and exit_mmap().
>>
>> Changelog v5->v4
>>
>> Move specific hooks in code to insert_vm_struct
>> Use mmap_sem to protect mm->owner from changing and mm->owner from
>> changing cgroups.
>>
>> ...
>>
>> + * brk(), sbrk()), stack expansion, mremap(), etc - called with
>> + * mmap_sem held.
>> + * decreasing - called with mmap_sem held.
>> + * This callback is called with mmap_sem held
>
> It's good to document the locking prerequisites but for rwsems, one
> should specify whether it must be held for reading or for writing.
>
> Of course, down_write() is a superset of down_read(), so if it's "held
> for reading" then either mode-of-holding is OK. But it's best to spell
> all that out.
>
Sure, will do
--
Warm Regards,
Balbir Singh
Linux Technology Center
IBM, ISTL
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists