linux-kernel - Re: [External] Re: vmscan: Reclaim unevictable pages

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <0b86dbca-cbc9-3b43-e3b9-8876bcc24f22@suse.cz>
Date:   Mon, 18 Mar 2019 09:42:50 +0100
From:   Vlastimil Babka <vbabka@...e.cz>
To:     Pankaj Suryawanshi <pankaj.suryawanshi@...fochips.com>,
        Kirill Tkhai <ktkhai@...tuozzo.com>,
        Michal Hocko <mhocko@...nel.org>,
        "aneesh.kumar@...ux.ibm.com" <aneesh.kumar@...ux.ibm.com>
Cc:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "minchan@...nel.org" <minchan@...nel.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "khandual@...ux.vnet.ibm.com" <khandual@...ux.vnet.ibm.com>,
        "hillf.zj@...baba-inc.com" <hillf.zj@...baba-inc.com>
Subject: Re: [External] Re: vmscan: Reclaim unevictable pages

On 3/15/19 11:11 AM, Pankaj Suryawanshi wrote:
> 
> [ cc Aneesh kumar, Anshuman, Hillf, Vlastimil]

Can you send a proper patch with changelog explaining the change? I
don't know the context of this thread.

> From: Pankaj Suryawanshi
> Sent: 15 March 2019 11:35:05
> To: Kirill Tkhai; Michal Hocko
> Cc: linux-kernel@...r.kernel.org; minchan@...nel.org; linux-mm@...ck.org
> Subject: Re: Re: [External] Re: vmscan: Reclaim unevictable pages
> 
> 
> 
> [ cc linux-mm ]
> 
> 
> From: Pankaj Suryawanshi
> Sent: 14 March 2019 19:14:40
> To: Kirill Tkhai; Michal Hocko
> Cc: linux-kernel@...r.kernel.org; minchan@...nel.org
> Subject: Re: Re: [External] Re: vmscan: Reclaim unevictable pages
> 
> 
> 
> Hello ,
> 
> Please ignore the curly braces, they are just for debugging.
> 
> Below is the updated patch.
> 
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index be56e2e..12ac353 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -998,7 +998,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
>                 sc->nr_scanned++;
> 
>                 if (unlikely(!page_evictable(page)))
> -                       goto activate_locked;
> +                      goto cull_mlocked;
> 
>                 if (!sc->may_unmap && page_mapped(page))
>                         goto keep_locked;
> @@ -1331,7 +1331,12 @@ static unsigned long shrink_page_list(struct list_head *page_list,
>                 } else
>                         list_add(&page->lru, &free_pages);
>                 continue;
> -
> +cull_mlocked:
> +                if (PageSwapCache(page))
> +                        try_to_free_swap(page);
> +                unlock_page(page);
> +                list_add(&page->lru, &ret_pages);
> +                continue;
>  activate_locked:
>                 /* Not a candidate for swapping, so reclaim swap space. */
>                 if (PageSwapCache(page) && (mem_cgroup_swap_full(page) ||
> 
> 
> 
> Regards,
> Pankaj
> 
> 
> From: Kirill Tkhai <ktkhai@...tuozzo.com>
> Sent: 14 March 2019 14:55:34
> To: Pankaj Suryawanshi; Michal Hocko
> Cc: linux-kernel@...r.kernel.org; minchan@...nel.org
> Subject: Re: Re: [External] Re: vmscan: Reclaim unevictable pages
> 
> 
> On 14.03.2019 11:52, Pankaj Suryawanshi wrote:
>>
>> I am using kernel version 4.14.65 (on Android pie [ARM]).
>>
>> No additional patches applied on top of vanilla.(Core MM).
>>
>> If  I change in the vmscan.c as below patch, it will work.
> 
> Sorry, but 4.14.65 does not have braces around trylock_page(),
> like in your patch below.
> 
> See     https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/mm/vmscan.c?h=v4.14.65
> 
> [...]
> 
>>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>>> index be56e2e..2e51edc 100644
>>> --- a/mm/vmscan.c
>>> +++ b/mm/vmscan.c
>>> @@ -990,15 +990,17 @@ static unsigned long shrink_page_list(struct list_head *page_list,
>>>                  page = lru_to_page(page_list);
>>>                  list_del(&page->lru);
>>>
>>>                 if (!trylock_page(page)) {
>>>                          goto keep;
>>>                 }
> 
> ************************************************************************************************************************************************************* eInfochips Business Disclaimer: This e-mail message and all attachments transmitted with it are intended solely for the use of the addressee and may contain legally privileged and confidential information. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution, copying, or other use of this message or its attachments is strictly prohibited. If you have received this message in error, please notify the sender immediately by replying to this message and please delete it from your computer. Any views expressed in this message are those of the individual sender unless otherwise stated. Company has taken enough precautions to prevent the spread of viruses. However the company accepts no liability for any damage caused by any virus transmitted by this email. *************************************************************************************************************************************************************
>