linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: David Rientjes <rientjes@google.com>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: linux-mm@kvack.org, kamezawa.hiroyu@jp.fujitsu.com,
	dhillf@gmail.com, mhocko@suse.cz, akpm@linux-foundation.org,
	hannes@cmpxchg.org, linux-kernel@vger.kernel.org,
	cgroups@vger.kernel.org, Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [PATCH -V7 02/14] hugetlbfs: don't use ERR_PTR with VM_FAULT* values
Date: Wed, 30 May 2012 23:50:18 -0700 (PDT)	[thread overview]
Message-ID: <alpine.DEB.2.00.1205302331380.25774@chino.kir.corp.google.com> (raw)
In-Reply-To: <20120531054533.GE24855@skywalker.linux.vnet.ibm.com>

On Thu, 31 May 2012, Aneesh Kumar K.V wrote:

> > Yeah, but is there a reason for using VM_FAULT_HWPOISON_LARGE_MASK since 
> > that's the only VM_FAULT_* value that is greater than MAX_ERRNO?  The rest 
> > of your patch set doesn't require this, so I think this change should just 
> > be dropped.  (And PTR_ERR() still returns long, this wasn't fixed from my 
> > original review.)
> > 
> 
> The changes was done as per Andrew's request so that we don't have such hidden
> dependencies on the values of VM_FAULT_*. Yes it can be a seperate patch from
> the patchset. I have changed int to long as per your review.
> 

I think it confuscates the code, can't we just add something like 
BUILD_BUG_ON() to ensure that PTR_ERR() never uses values that are outside 
the bounds of MAX_ERRNO so we'll catch these at compile time if 
mm/hugetlb.c or anything else is ever extended to use such values?

--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2012-05-31  6:50 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-30 14:38 [PATCH -V7 00/14] hugetlb: Add HugeTLB controller to control HugeTLB allocation Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 01/14] hugetlb: rename max_hstate to hugetlb_max_hstate Aneesh Kumar K.V
2012-05-31  0:48   ` Konrad Rzeszutek Wilk
2012-05-31  5:47     ` Aneesh Kumar K.V
2012-05-31  0:55   ` David Rientjes
2012-05-30 14:38 ` [PATCH -V7 02/14] hugetlbfs: don't use ERR_PTR with VM_FAULT* values Aneesh Kumar K.V
2012-05-31  0:54   ` Konrad Rzeszutek Wilk
2012-05-31  1:02   ` David Rientjes
2012-05-31  5:45     ` Aneesh Kumar K.V
2012-05-31  6:50       ` David Rientjes [this message]
2012-05-30 14:38 ` [PATCH -V7 03/14] hugetlbfs: add an inline helper for finding hstate index Aneesh Kumar K.V
2012-05-31  1:05   ` David Rientjes
2012-05-30 14:38 ` [PATCH -V7 04/14] hugetlb: use mmu_gather instead of a temporary linked list for accumulating pages Aneesh Kumar K.V
2012-05-31  1:56   ` David Rientjes
2012-05-31  5:35     ` Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 05/14] hugetlb: avoid taking i_mmap_mutex in unmap_single_vma() for hugetlb Aneesh Kumar K.V
2012-05-31  1:57   ` David Rientjes
2012-05-31  5:25     ` Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 06/14] hugetlb: simplify migrate_huge_page() Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 07/14] mm/page_cgroup: Make page_cgroup point to the cgroup rather than the mem_cgroup Aneesh Kumar K.V
2012-06-05  1:44   ` Kamezawa Hiroyuki
2012-06-05  2:53     ` Aneesh Kumar K.V
2012-06-05  3:40       ` Kamezawa Hiroyuki
2012-06-07 19:05         ` Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 08/14] hugetlbfs: add a list for tracking in-use HugeTLB pages Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 09/14] hugetlbfs: Make some static variables global Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 10/14] hugetlbfs: Add new HugeTLB cgroup Aneesh Kumar K.V
2012-05-31  1:19   ` Konrad Rzeszutek Wilk
2012-05-31  5:43     ` Aneesh Kumar K.V
2012-05-31  9:43       ` Michal Hocko
2012-05-31 14:01   ` Michal Hocko
2012-05-30 14:38 ` [PATCH -V7 11/14] hugetlbfs: add hugetlb cgroup control files Aneesh Kumar K.V
2012-05-31  1:32   ` Konrad Rzeszutek Wilk
2012-05-31  5:39     ` Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 12/14] hugetlb: add charge/uncharge calls for HugeTLB alloc/free Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 13/14] hugetlb: migrate hugetlb cgroup info from oldpage to new page during migration Aneesh Kumar K.V
2012-05-30 14:38 ` [PATCH -V7 14/14] hugetlb: add HugeTLB controller documentation Aneesh Kumar K.V

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=alpine.DEB.2.00.1205302331380.25774@chino.kir.corp.google.com \
    --to=rientjes@google.com \
    --cc=aarcange@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=aneesh.kumar@linux.vnet.ibm.com \
    --cc=cgroups@vger.kernel.org \
    --cc=dhillf@gmail.com \
    --cc=hannes@cmpxchg.org \
    --cc=kamezawa.hiroyu@jp.fujitsu.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.cz \
    /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