From: Weijie Yang <weijie.yang.kh@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Weijie Yang <weijie.yang@samsung.com>,
akpm@linux-foundation.org, sjennings@variantweb.net,
bob.liu@oracle.com, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH RESEND 2/2] mm/zswap: refoctor the get/put routines
Date: Sat, 26 Oct 2013 17:46:00 +0800 [thread overview]
Message-ID: <CAL1ERfOhhJ12zXwsGJoHWRzkd2destQnJ32nfU25SOACCnzy7Q@mail.gmail.com> (raw)
In-Reply-To: <20131025102032.GE6612@gmail.com>
On Fri, Oct 25, 2013 at 6:20 PM, Minchan Kim <minchan@kernel.org> wrote:
> On Thu, Oct 24, 2013 at 05:53:32PM +0800, Weijie Yang wrote:
>> The refcount routine was not fit the kernel get/put semantic exactly,
>> There were too many judgement statements on refcount and it could be minus.
>>
>> This patch does the following:
>>
>> - move refcount judgement to zswap_entry_put() to hide resource free function.
>>
>> - add a new function zswap_entry_find_get(), so that callers can use easily
>> in the following pattern:
>>
>> zswap_entry_find_get
>> .../* do something */
>> zswap_entry_put
>>
>> - to eliminate compile error, move some functions declaration
>>
>> This patch is based on Minchan Kim <minchan@kernel.org> 's idea and suggestion.
>>
>> Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
>> Cc: Seth Jennings <sjennings@variantweb.net>
>> Cc: Minchan Kim <minchan@kernel.org>
>> Cc: Bob Liu <bob.liu@oracle.com>
>
>
> I remember Bob had a idea to remove a look up and I think it's doable.
> Anyway, I don't mind you send it with fix or not.
Thanks for review.
Bob's idea is:
"Then how about use if (!RB_EMPTY_NODE(&entry->rbnode)) to
replace rbtree searching?"
I'm afraid not. Because entry could be freed in previous zswap_entry_put,
we cann't reference entry or we would touch a free-and-use issue.
> Thanks for handling this, Weijie!
>
> Acked-by: Minchan Kim <minchan@kernel.org>
>
> --
> Kind regards,
> Minchan Kim
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
prev parent reply other threads:[~2013-10-26 9:46 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-24 9:53 [PATCH RESEND 2/2] mm/zswap: refoctor the get/put routines Weijie Yang
2013-10-25 10:20 ` Minchan Kim
2013-10-26 9:46 ` Weijie Yang [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAL1ERfOhhJ12zXwsGJoHWRzkd2destQnJ32nfU25SOACCnzy7Q@mail.gmail.com \
--to=weijie.yang.kh@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=bob.liu@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=minchan@kernel.org \
--cc=sjennings@variantweb.net \
--cc=stable@vger.kernel.org \
--cc=weijie.yang@samsung.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).