From: Dan Carpenter <dan.carpenter@oracle.com>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: linux-mm@kvack.org
Subject: Re: mm: keep page cache radix tree nodes in check
Date: Thu, 10 Mar 2016 22:35:22 +0300 [thread overview]
Message-ID: <20160310193522.GC5273@mwanda> (raw)
In-Reply-To: <20160310161200.GA11651@cmpxchg.org>
On Thu, Mar 10, 2016 at 11:12:00AM -0500, Johannes Weiner wrote:
> We know that page->tree[page->index] is present and the tree is
> locked, so __radix_tree_lookup() will always return with an entry, as
> well as &node and &slot set. I'm not sure how you would annotate this.
>
That's tricky...
> Is it also warning about slot?
It does, yes.
> Or can it know that they are always set
> together?
It knows they are set together but it warns about both.
> Could it maybe be linked to the function's return value? I
> would prefer not setting node and slot to NULL to suppress the false
> positive. However, what we could do is add a BUG_ON() if the function
> call returns NULL. Would that be enough of a hint to the checker that
> we expect the function to be always successful and set node and slot?
I'm sort of just trying to get a feel for what the issues are. Calling
BUG_ON() would silence the warning, yes.
regards,
dan carpenter
--
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:[~2016-03-10 19:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-10 12:59 mm: keep page cache radix tree nodes in check Dan Carpenter
2016-03-10 16:12 ` Johannes Weiner
2016-03-10 19:35 ` Dan Carpenter [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=20160310193522.GC5273@mwanda \
--to=dan.carpenter@oracle.com \
--cc=hannes@cmpxchg.org \
--cc=linux-mm@kvack.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.